Sample records for materials semiconductor metal

  1. Superatoms and Metal-Semiconductor Motifs for Cluster Materials

    SciTech Connect (OSTI)

    Castleman, A. W.

    2013-10-11T23:59:59.000Z

    A molecular understanding of catalysis and catalytically active materials is of fundamental importance in designing new substances for applications in energy and fuels. We have performed reactivity studies and ultrafast ionization and coulomb explosion studies on a variety of catalytically-relevant materials, including transition metal oxides of Fe, Co, Ni, Cu, Ti, V, Nb, and Ta. We demonstrate that differences in charge state, geometry, and elemental composition of clusters of such materials determine chemical reactivity and ionization behavior, crucial steps in improving performance of catalysts.

  2. Magnetization dynamics and spin diffusion in semiconductors and metals

    E-Print Network [OSTI]

    Cywi?ski, ?ukasz

    2007-01-01T23:59:59.000Z

    to (III,Mn)V ferromagnetic semiconductors . . . . . . . . .semiconductors . . . . . . . . . . . . . . . . . .Spin di?usion in semiconductors and metals: a general

  3. Hydrogenated Graphene Nanoflakes: Semiconductor to Half-Metal...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hydrogenated Graphene Nanoflakes: Semiconductor to Half-Metal Transition and Remarkable Large Magnetism. Hydrogenated Graphene Nanoflakes: Semiconductor to Half-Metal Transition...

  4. ECE 344--Semiconductor Devices & Materials ECE Department, UMass Amherst

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    1 Syllabus ECE 344--Semiconductor Devices & Materials ECE Department, UMass Amherst Fall 2013 transport in semiconductors Explain the operating principles in semiconductor devices (diodes, capacitors Topics: Fundamentals of Semiconductors; Theory of Electrical Conduction; Device Operations (See "Class

  5. Semiconductor device PN junction fabrication using optical processing of amorphous semiconductor material

    DOE Patents [OSTI]

    Sopori, Bhushan; Rangappan, Anikara

    2014-11-25T23:59:59.000Z

    Systems and methods for semiconductor device PN junction fabrication are provided. In one embodiment, a method for fabricating an electrical device having a P-N junction comprises: depositing a layer of amorphous semiconductor material onto a crystalline semiconductor base, wherein the crystalline semiconductor base comprises a crystalline phase of a same semiconductor as the amorphous layer; and growing the layer of amorphous semiconductor material into a layer of crystalline semiconductor material that is epitaxially matched to the lattice structure of the crystalline semiconductor base by applying an optical energy that penetrates at least the amorphous semiconductor material.

  6. Fabrication and characterization of metal-semiconductor-metal nanorod using template synthesis

    SciTech Connect (OSTI)

    Kim, Kyohyeok; Kwon, Namyong; Hong, Junki; Chung, Ilsub [Sungkyunkwan University Advanced Institute of Nanotechnology, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Sungkyunkwan University Advanced Institute of Nanotechnology and Information and Communication Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2009-07-15T23:59:59.000Z

    The authors attempted to fabricate and characterize one dimensional metal-semiconductor-metal (MSM) nanorod using a template. Cadmium selenide (CdSe) and polypyrrole (Ppy) were chosen as n-type and p-type semiconductor materials, respectively, whereas Au was chosen as a metal electrode. The fabrication of the nanorod was achieved by ''template synthesis'' method using polycarbonate membrane. The structure of the fabricated nanorod was analyzed using scanning electron microscopy and energy dispersive spectroscopy. In addition, the electrical properties of MSM nanorods were characterized using scanning probe microscopy (Seiko Instruments, SPA 300 HV) by probing with a conductive cantilever. I-V characteristics as a function of the temperature give the activation energy, as well as the barrier height of a metal-semiconductor contact, which is useful to understand the conduction mechanism of MSM nanorods.

  7. Method of physical vapor deposition of metal oxides on semiconductors

    DOE Patents [OSTI]

    Norton, David P. (Knoxville, TN)

    2001-01-01T23:59:59.000Z

    A process for growing a metal oxide thin film upon a semiconductor surface with a physical vapor deposition technique in a high-vacuum environment and a structure formed with the process involves the steps of heating the semiconductor surface and introducing hydrogen gas into the high-vacuum environment to develop conditions at the semiconductor surface which are favorable for growing the desired metal oxide upon the semiconductor surface yet is unfavorable for the formation of any native oxides upon the semiconductor. More specifically, the temperature of the semiconductor surface and the ratio of hydrogen partial pressure to water pressure within the vacuum environment are high enough to render the formation of native oxides on the semiconductor surface thermodynamically unstable yet are not so high that the formation of the desired metal oxide on the semiconductor surface is thermodynamically unstable. Having established these conditions, constituent atoms of the metal oxide to be deposited upon the semiconductor surface are directed toward the surface of the semiconductor by a physical vapor deposition technique so that the atoms come to rest upon the semiconductor surface as a thin film of metal oxide with no native oxide at the semiconductor surface/thin film interface. An example of a structure formed by this method includes an epitaxial thin film of (001)-oriented CeO.sub.2 overlying a substrate of (001) Ge.

  8. Metal Oxide Semiconductor Nanoparticles Open the Door to New...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Innovations Technology available for licensing: novel nanometer-sized metal oxide semiconductors that allow targeting, initiating and control of in vitro and in vivo chemical...

  9. Conduction properties of metal/organic monolayer/semiconductor heterostructures

    SciTech Connect (OSTI)

    Li, D.; Bishop, A.; Gim, Y.; Shi, X.B.; Fitzsimmons, M.R.; Jia, Q.X. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    1998-11-01T23:59:59.000Z

    We have fabricated and characterized rectifying devices made of metal/organic monolayer/semiconductor heterostructures. The devices consist of an organic barrier layer sandwiched between an aluminum (Al) metal contact and a {ital p}-type Si semiconductor. The barrier materials were chosen from three types of self-assembled monolayers (SAMs) with different electronic properties: (1) wide-band gap poly(diallydimethyl ammonium) chloride (PDDA), (2) narrow-band gap PDDA/NiPc (nickel phthalocyanine tetrasulfonate), and (3) donor type PDDA/PPP (poly {ital p}-quaterphenylene-disulfonic-dicarboxylic acid). From current{endash}voltage (I{endash}V) measurements at room temperature, we have found the turn-on voltage of the devices can be tuned by varying the structure, hence electronic properties, of the organic monolayers, and that there exists a power-law dependence of {ital I} on V, I{proportional_to}V{sup {alpha}}, with the exponent {alpha}=2.2 for PDDA, 2.7 for PDDA/NiPc, and 1.44 for PDDA/PPP as the barrier layer, respectively. Our results imply that the transport properties are controlled by both the electronic properties of the SAMs and those of the metal and semiconductor, as indicated by the power-law dependence of the I{endash}V characteristics. {copyright} {ital 1998 American Institute of Physics.}

  10. Lattice matched semiconductor growth on crystalline metallic substrates

    DOE Patents [OSTI]

    Norman, Andrew G; Ptak, Aaron J; McMahon, William E

    2013-11-05T23:59:59.000Z

    Methods of fabricating a semiconductor layer or device and said devices are disclosed. The methods include but are not limited to providing a metal or metal alloy substrate having a crystalline surface with a known lattice parameter (a). The methods further include growing a crystalline semiconductor alloy layer on the crystalline substrate surface by coincident site lattice matched epitaxy. The semiconductor layer may be grown without any buffer layer between the alloy and the crystalline surface of the substrate. The semiconductor alloy may be prepared to have a lattice parameter (a') that is related to the lattice parameter (a). The semiconductor alloy may further be prepared to have a selected band gap.

  11. Semiconductor bridge, SCB, ignition of energetic materials

    SciTech Connect (OSTI)

    Bickes, R.W.; Grubelich, M.D.; Harris, S.M.; Merson, J.A.; Tarbell, W.W.

    1997-04-01T23:59:59.000Z

    Sandia National Laboratories` semiconductor bridge, SCB, is now being used for the ignition or initiation of a wide variety of exeoergic materials. Applications of this new technology arose because of a need at the system level to provide light weight, small volume and low energy explosive assemblies. Conventional bridgewire devices could not meet the stringent size, weight and energy requirements of our customers. We present an overview of SCB technology and the ignition characteristics for a number of energetic materials including primary and secondary explosives, pyrotechnics, thermites and intermetallics. We provide examples of systems designed to meet the modern requirements that sophisticated systems must satisfy in today`s market environments.

  12. Ultrathin metal-semiconductor-metal resonator for angle invariant visible band transmission filters

    SciTech Connect (OSTI)

    Lee, Kyu-Tae; Seo, Sungyong; Yong Lee, Jae; Jay Guo, L., E-mail: guo@umich.edu [Department of Electrical Engineering and Computer Science, The University of Michigan, Ann Arbor, Michigan 48109 (United States)

    2014-06-09T23:59:59.000Z

    We present transmission visible wavelength filters based on strong interference behaviors in an ultrathin semiconductor material between two metal layers. The proposed devices were fabricated on 2?cm?×?2?cm glass substrate, and the transmission characteristics show good agreement with the design. Due to a significantly reduced light propagation phase change associated with the ultrathin semiconductor layer and the compensation in phase shift of light reflecting from the metal surface, the filters show an angle insensitive performance up to ±70°, thus, addressing one of the key challenges facing the previously reported photonic and plasmonic color filters. This principle, described in this paper, can have potential for diverse applications ranging from color display devices to the image sensors.

  13. Method for depositing high-quality microcrystalline semiconductor materials

    DOE Patents [OSTI]

    Guha, Subhendu (Bloomfield Hills, MI); Yang, Chi C. (Troy, MI); Yan, Baojie (Rochester Hills, MI)

    2011-03-08T23:59:59.000Z

    A process for the plasma deposition of a layer of a microcrystalline semiconductor material is carried out by energizing a process gas which includes a precursor of the semiconductor material and a diluent with electromagnetic energy so as to create a plasma therefrom. The plasma deposits a layer of the microcrystalline semiconductor material onto the substrate. The concentration of the diluent in the process gas is varied as a function of the thickness of the layer of microcrystalline semiconductor material which has been deposited. Also disclosed is the use of the process for the preparation of an N-I-P type photovoltaic device.

  14. Method of preparing nitrogen containing semiconductor material

    DOE Patents [OSTI]

    Barber, Greg D.; Kurtz, Sarah R.

    2004-09-07T23:59:59.000Z

    A method of combining group III elements with group V elements that incorporates at least nitrogen from a nitrogen halide for use in semiconductors and in particular semiconductors in photovoltaic cells.

  15. Metal-doped semiconductor nanoparticles and methods of synthesis thereof

    DOE Patents [OSTI]

    Ren, Zhifeng (Newton, MA); Chen, Gang (Carlisle, MA); Poudel, Bed (West Newton, MA); Kumar, Shankar (Newton, MA); Wang, Wenzhong (Beijing, CN); Dresselhaus, Mildred (Arlington, MA)

    2009-09-08T23:59:59.000Z

    The present invention generally relates to binary or higher order semiconductor nanoparticles doped with a metallic element, and thermoelectric compositions incorporating such nanoparticles. In one aspect, the present invention provides a thermoelectric composition comprising a plurality of nanoparticles each of which includes an alloy matrix formed of a Group IV element and Group VI element and a metallic dopant distributed within the matrix.

  16. Composition/bandgap selective dry photochemical etching of semiconductor materials

    DOE Patents [OSTI]

    Ashby, C.I.H.; Dishman, J.L.

    1985-10-11T23:59:59.000Z

    Disclosed is a method of selectively photochemically dry etching a first semiconductor material of a given composition and direct bandgap Eg/sub 1/ in the presence of a second semiconductor material of a different composition and direct bandgap Eg/sub 2/, wherein Eg/sub 2/ > Eg/sub 1/, said second semiconductor material substantially not being etched during said method. The method comprises subjecting both materials to the same photon flux and to the same gaseous etchant under conditions where said etchant would be ineffective for chemical etching of either material were the photons not present, said photons being of an energy greater than Eg/sub 1/ but less than Eg/sub 2/, whereby said first semiconductor material is photochemically etched and said second material is substantially not etched.

  17. Low resistance barrier layer for isolating, adhering, and passivating copper metal in semiconductor fabrication

    DOE Patents [OSTI]

    Weihs, Timothy P. (Baltimore, MD); Barbee, Jr., Troy W. (Palto Alto, CA)

    2002-01-01T23:59:59.000Z

    Cubic or metastable cubic refractory metal carbides act as barrier layers to isolate, adhere, and passivate copper in semiconductor fabrication. One or more barrier layers of the metal carbide are deposited in conjunction with copper metallizations to form a multilayer characterized by a cubic crystal structure with a strong (100) texture. Suitable barrier layer materials include refractory transition metal carbides such as vanadium carbide (VC), niobium carbide (NbC), tantalum carbide (TaC), chromium carbide (Cr.sub.3 C.sub.2), tungsten carbide (WC), and molybdenum carbide (MoC).

  18. ECE 609 Semiconductor Devices Department of Electrical and Computer Engineering

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    ECE 609 ­ Semiconductor Devices Department of Electrical and Computer Engineering University. ________________________________________________________________________ Preliminary Course Outline 1. Overview of Semiconductor Physics 1.1 Semiconductor Materials-V Characteristics, Nonideal Behavior) 2.2 Metal Semiconductor Junctions (Schottky Barriers, Ohmic Contacts) 2

  19. Metal-sensing layer-semiconductor and metal-sensing layer-metal heterostructure gas sensors

    SciTech Connect (OSTI)

    O'Leary, M.; Li, Zheng; Fonash, S.J.

    1987-01-01T23:59:59.000Z

    Extremely sensitive gas sensors can be fabricated using heterostructures of the form metal-sensing layer-semiconductor or metal-sensing layer-metal. These structures are heterostructure diodes which have the barrier controlling transport at least partially located in the sensing layer. In the presence of the gas species to be detected, the electrical properties of the sensing layer evolve, resulting in a modification of the barrier to electric current transport and, hence, resulting in detection due to changes in the current-voltage characteristics of the device. This type of sensor structure is demonstrated using the Pd/Ti-O/sub x/Ti heterostructure hydrogen detector.

  20. Al-doped HfO2/In0.53Ga0.47As metal-oxide-semiconductor capaci

    E-Print Network [OSTI]

    Stemmer, Susanne

    2011-01-01T23:59:59.000Z

    MOS (Metal Oxide Semiconductor) Phys- ics and Technologywas funded by the Semiconductor Re- search Corporation0.47 As metal-oxide-semiconductor capacitors Yoontae Hwang,

  1. Antiferromagnetic half-metals, gapless half-metals, and spin gapless semiconductors: The D0{sub 3}-type Heusler alloys

    SciTech Connect (OSTI)

    Gao, G. Y., E-mail: guoying-gao@mail.hust.edu.cn; Yao, Kai-Lun, E-mail: klyao@mail.hust.edu.cn [School of Physics and Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074 (China)] [School of Physics and Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2013-12-02T23:59:59.000Z

    High-spin-polarization materials are desired for the realization of high-performance spintronic devices. We combine recent experimental and theoretical findings to theoretically design several high-spin-polarization materials in binary D0{sub 3}-type Heusler alloys: gapless (zero-gap) half-metallic ferrimagnets of V{sub 3}Si and V{sub 3}Ge, half-metallic antiferromagnets of Mn{sub 3}Al and Mn{sub 3}Ga, half-metallic ferrimagnets of Mn{sub 3}Si and Mn{sub 3}Ge, and a spin gapless semiconductor of Cr{sub 3}Al. The high spin polarization, zero net magnetic moment, zero energy gap, and slight disorder compared to the ternary and quaternary Heusler alloys make these binary materials promising candidates for spintronic applications. All results are obtained by the electronic structure calculations from first-principles.

  2. Corrosion protective coating for metallic materials

    DOE Patents [OSTI]

    Buchheit, Rudolph G. (Albuquerque, NM); Martinez, Michael A. (Albuquerque, NM)

    1998-01-01T23:59:59.000Z

    Corrosion protective coatings for metallic materials, particularly aluminum and aluminum alloys, produced with simple, low-cost equipment and materials other than toxic metals or metal salts, or metal cyanides. The metallic material is cleaned, degreased, and deoxidized, the surface is converted to a substantially alkaline condition, and the surface is chemically sealed with inorganic metal compounds.

  3. Corrosion protective coating for metallic materials

    DOE Patents [OSTI]

    Buchheit, R.G.; Martinez, M.A.

    1998-05-26T23:59:59.000Z

    Corrosion protective coatings for metallic materials, particularly aluminum and aluminum alloys, produced with simple, low-cost equipment and materials other than toxic metals or metal salts, or metal cyanides is disclosed. The metallic material is cleaned, degreased, and deoxidized, the surface is converted to a substantially alkaline condition, and the surface is chemically sealed with inorganic metal compounds. 1 fig.

  4. Metal recovery from porous materials

    DOE Patents [OSTI]

    Sturcken, E.F.

    1991-01-01T23:59:59.000Z

    The present invention relates to recovery of metals. More specifically, the present invention relates to the recovery of plutonium and other metals from porous materials using microwaves. The United States Government has rights in this invention pursuant to Contract No. DE-AC09-89SR18035 between the US Department of Energy and Westinghouse Savannah River Company.

  5. Polarization dependence of the temporal response of metal-semiconductor-metal photodetectors

    E-Print Network [OSTI]

    Van Driel, Henry M.

    of MSM-PD effi- ciency when the electrode period ( ) is comparable to the wavelength of the incident-semiconductor-metal photodetector temporal response is shown to be significant, and largest for devices with electrode periods less insensitive devices require special electrode patterning7 or . When used as a polarization analyzer/ detector

  6. Structure and magnetism of transition-metal implanted dilute magnetic semiconductors

    E-Print Network [OSTI]

    Pereira, Lino; Temst, K; Araújo, JP; Wahl, U

    The discovery of a dilute magnetic semiconductor (DMS) in which ferromagnetism is carrier-mediated and persists above room temperature is a critical step towards the development of semiconductor-based spintronics. Among the many types of DMS materials which have been investigated, the current research interest can be narrowed down to two main classes of materials: (1) narrow-gap III-V semiconductors, mostly GaAs and InAs, doped with Mn; (2) wide-gap oxides and nitrides doped with 3d transition metals, mostly Mn- and Co-doped ZnO and Mn-doped GaN. With a number of interesting functionalities deriving from the carrier-mediated ferromagnetism and demonstrated in various proof-of-concept devices, Mn-doped GaAs has become, among DMS materials, one of the best candidates for technological application. However, despite major developments over the last 15 years, the maximum Curie temperature (185 K) remains well below room temperature. On the other hand, wide-gap DMS materials appear to exhibit ferromagnetic behavior...

  7. Wafer Fusion for Integration of Semiconductor Materials and Devices

    SciTech Connect (OSTI)

    Choquette, K.D.; Geib, K.M.; Hou, H.Q.; Allerman, A.A.; Kravitz, S.; Follstaedt, D.M.; Hindi, J.J.

    1999-05-01T23:59:59.000Z

    We have developed a wafer fusion technology to achieve integration of semiconductor materials and heterostructures with widely disparate lattice parameters, electronic properties, and/or optical properties for novel devices not now possible on any one substrate. Using our simple fusion process which uses low temperature (400-600 C) anneals in inert N{sub 2} gas, we have extended the scope of this technology to examine hybrid integration of dissimilar device technologies. As a specific example, we demonstrate wafer bonding vertical cavity surface emitting lasers (VCSELs) to transparent AlGaAs and GaP substrates to fabricate bottom-emitting short wavelength VCSELs. As a baseline fabrication technology applicable to many semiconductor systems, wafer fusion will revolutionize the way we think about possible semiconductor devices, and enable novel device configurations not possible by epitaxial growth.

  8. Metal recovery from porous materials

    DOE Patents [OSTI]

    Sturcken, Edward F. (P.O. Box 900, Isle of Palms, SC 29451)

    1992-01-01T23:59:59.000Z

    A method for recovering plutonium and other metals from materials by leaching comprising the steps of incinerating the materials to form a porous matrix as the residue of incineration, immersing the matrix into acid in a microwave-transparent pressure vessel, sealing the pressure vessel, and applying microwaves so that the temperature and the pressure in the pressure vessel increase. The acid for recovering plutonium can be a mixture of HBF.sub.4 and HNO.sub.3 and preferably the pressure is increased to at least 100 PSI and the temperature to at least 200.degree. C. The porous material can be pulverized before immersion to further increase the leach rate.

  9. First principles study of Fe in diamond: A diamond-based half metallic dilute magnetic semiconductor

    SciTech Connect (OSTI)

    Benecha, E. M. [Department of Physics, University of South Africa, P.O. Box 392, UNISA 0003 Pretoria (South Africa); Lombardi, E. B., E-mail: lombaeb@unisa.ac.za [College of Graduate Studies, University of South Africa, P.O. Box 392, UNISA 0003 Pretoria (South Africa)

    2013-12-14T23:59:59.000Z

    Half-metallic ferromagnetic ordering in semiconductors, essential in the emerging field of spintronics for injection and transport of highly spin polarised currents, has up to now been considered mainly in III–V and II–VI materials. However, low Curie temperatures have limited implementation in room temperature device applications. We report ab initio Density Functional Theory calculations on the properties of Fe in diamond, considering the effects of lattice site, charge state, and Fermi level position. We show that the lattice sites and induced magnetic moments of Fe in diamond depend strongly on the Fermi level position and type of diamond co-doping, with Fe being energetically most favorable at the substitutional site in p-type and intrinsic diamond, while it is most stable at a divacancy site in n-type diamond. Fe induces spin polarized bands in the band gap, with strong hybridization between Fe-3d and C-2s,2p bands. We further consider Fe-Fe spin interactions in diamond and show that substitutional Fe{sup +1} in p-type diamond exhibits a half-metallic character, with a magnetic moment of 1.0??{sub B} per Fe atom and a large ferromagnetic stabilization energy of 33?meV, an order of magnitude larger than in other semiconductors, with correspondingly high Curie temperatures. These results, combined with diamond's unique properties, demonstrate that Fe doped p-type diamond is likely to be a highly suitable candidate material for spintronics applications.

  10. Mesoscopic pointlike defects in semiconductors: Deep-level energies D. D. Nolte

    E-Print Network [OSTI]

    Nolte, David D.

    -semiconductor heterostructures to include metal-semiconductor,1 insulator-semiconductor, and superconductor-semiconductor

  11. Multiple percolation tunneling staircase in metal-semiconductor nanoparticle composites

    SciTech Connect (OSTI)

    Mukherjee, Rupam; Huang, Zhi-Feng; Nadgorny, Boris [Department of Physics and Astronomy, Wayne State University, Detroit, Michigan 48201 (United States)

    2014-10-27T23:59:59.000Z

    Multiple percolation transitions are observed in a binary system of RuO{sub 2}-CaCu{sub 3}Ti{sub 4}O{sub 12} metal-semiconductor nanoparticle composites near percolation thresholds. Apart from a classical percolation transition, associated with the appearance of a continuous conductance path through RuO{sub 2} metal oxide nanoparticles, at least two additional tunneling percolation transitions are detected in this composite system. Such behavior is consistent with the recently emerged picture of a quantum conductivity staircase, which predicts several percolation tunneling thresholds in a system with a hierarchy of local tunneling conductance, due to various degrees of proximity of adjacent conducting particles distributed in an insulating matrix. Here, we investigate a different type of percolation tunneling staircase, associated with a more complex conductive and insulating particle microstructure of two types of non-spherical constituents. As tunneling is strongly temperature dependent, we use variable temperature measurements to emphasize the hierarchical nature of consecutive tunneling transitions. The critical exponents corresponding to specific tunneling percolation thresholds are found to be nonuniversal and temperature dependent.

  12. Metal recovery from porous materials

    DOE Patents [OSTI]

    Sturcken, E.F.

    1992-10-13T23:59:59.000Z

    A method is described for recovering plutonium and other metals from materials by leaching comprising the steps of incinerating the materials to form a porous matrix as the residue of incineration, immersing the matrix into acid in a microwave-transparent pressure vessel, sealing the pressure vessel, and applying microwaves so that the temperature and the pressure in the pressure vessel increase. The acid for recovering plutonium can be a mixture of HBF[sub 4] and HNO[sub 3] and preferably the pressure is increased to at least 100 PSI and the temperature to at least 200 C. The porous material can be pulverized before immersion to further increase the leach rate.

  13. Self-Assembled Metal/Molecule/Semiconductor Nanostructures for Electronic Device

    E-Print Network [OSTI]

    Woodall, Jerry M.

    565 Self-Assembled Metal/Molecule/Semiconductor Nanostructures for Electronic Device and Contact attracted interest for electronic device and ma- terials applications. The first class involves the for-assembled semiconductor structures, the electronic device functionality has been limited by the difficulty in achieving

  14. System for characterizing semiconductor materials and photovoltaic devices through calibration

    DOE Patents [OSTI]

    Sopori, B.L.; Allen, L.C.; Marshall, C.; Murphy, R.C.; Marshall, T.

    1998-05-26T23:59:59.000Z

    A method and apparatus are disclosed for measuring characteristics of a piece of material, typically semiconductor materials including photovoltaic devices. The characteristics may include dislocation defect density, grain boundaries, reflectance, external LBIC, internal LBIC, and minority carrier diffusion length. The apparatus includes a light source, an integrating sphere, and a detector communicating with a computer. The measurement or calculation of the characteristics is calibrated to provide accurate, absolute values. The calibration is performed by substituting a standard sample for the piece of material, the sample having a known quantity of one or more of the relevant characteristics. The quantity measured by the system of the relevant characteristic is compared to the known quantity and a calibration constant is created thereby. 44 figs.

  15. System for characterizing semiconductor materials and photovoltaic devices through calibration

    DOE Patents [OSTI]

    Sopori, Bhushan L. (Denver, CO); Allen, Larry C. (Arvada, CO); Marshall, Craig (Littleton, CO); Murphy, Robert C. (Golden, CO); Marshall, Todd (Littleton, CO)

    1998-01-01T23:59:59.000Z

    A method and apparatus for measuring characteristics of a piece of material, typically semiconductor materials including photovoltaic devices. The characteristics may include dislocation defect density, grain boundaries, reflectance, external LBIC, internal LBIC, and minority carrier diffusion length. The apparatus includes a light source, an integrating sphere, and a detector communicating with a computer. The measurement or calculation of the characteristics is calibrated to provide accurate, absolute values. The calibration is performed by substituting a standard sample for the piece of material, the sample having a known quantity of one or more of the relevant characteristics. The quantity measured by the system of the relevant characteristic is compared to the known quantity and a calibration constant is created thereby.

  16. active complementary metal-oxide-semiconductor: Topics by E-print...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Metal Oxide Semiconductor (CMOS) tech- Corresponding author. Email address: antonio 465 Tycho Brahe CCD CMOS Physics Websites Summary: 12;12;12;117 Tycho Brahe 20 19 70 CCD...

  17. Nanocomposite of graphene and metal oxide materials

    DOE Patents [OSTI]

    Liu, Jun; Aksay, Ilhan A.; Choi, Daiwon; Wang, Donghai; Yang, Zhenguo

    2013-10-15T23:59:59.000Z

    Nanocomposite materials comprising a metal oxide bonded to at least one graphene material. The nanocomposite materials exhibit a specific capacity of at least twice that of the metal oxide material without the graphene at a charge/discharge rate greater than about 10 C.

  18. Nanocomposite of graphene and metal oxide materials

    DOE Patents [OSTI]

    Liu, Jun; Aksay, Ilhan A.; Choi, Daiwon; Wang, Donghai; Yang, Zhenguo

    2012-09-04T23:59:59.000Z

    Nanocomposite materials comprising a metal oxide bonded to at least one graphene material. The nanocomposite materials exhibit a specific capacity of at least twice that of the metal oxide material without the graphene at a charge/discharge rate greater than about 10C.

  19. Development of epitaxial AlxSc1-xN for artificially structured metal/semiconductor superlattice metamaterials

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sands, Timothy D.; Stach, Eric A.; Saha, Bivas; Saber, Sammy; Naik, Gururaj V.; Boltasseva, Alexandra; Kvam, Eric P.

    2015-02-01T23:59:59.000Z

    Epitaxial nitride rocksalt metal/semiconductor superlattices are emerging as a novel class of artificially structured materials that have generated significant interest in recent years for their potential application in plasmonic and thermoelectric devices. Though most nitride metals are rocksalt, nitride semiconductors in general have hexagonal crystal structure. We report rocksalt aluminum scandium nitride (Al,Sc)N alloys as the semiconducting component in epitaxial rocksalt metal/semiconductor superlattices. The AlxSc1?xN alloys when deposited directly on MgO substrates are stabilized in a homogeneous rocksalt (single) phase when x?more »has been extended to x?xSc1?xN alloys show moderate direct bandgap bowing with a bowing parameter, B?=?1.41?±?0.19?eV. The direct bandgap of metastable rocksalt AlN is extrapolated to be 4.70?±?0.20?eV. The tunable lattice parameter, bandgap, dielectric permittivity, and electronic properties of rocksalt AlxSc1?xN alloys enable high quality epitaxial rocksalt metal/AlxSc1?xN superlattices with a wide range of accessible metamaterials properties.« less

  20. Methods of use of semiconductor nanocrystal probes for treating a material

    DOE Patents [OSTI]

    Weiss, Shimon (Los Angeles, CA); Bruchez, Marcel (Belmont, CA); Alivisatos, Paul (Oakland, CA)

    2007-04-27T23:59:59.000Z

    A semiconductor nanocrystal compound and probe are described. The compound is capable of linking to one or more affinity molecules. The compound comprises (1) one or more semiconductor nanocrystals capable of, in response to exposure to a first energy, providing a second energy, and (2) one or more linking agents, having a first portion linked to one or more semiconductor nanocrystals and a second portion capable of linking to one or more affinity molecules. One or more semiconductor nanocrystal compounds are linked to one or more affinity molecules to form a semiconductor nanocrystal probe capable of bonding with one or more detectable substances in a material being analyzed, and capable of, in response to exposure to a first energy, providing a second energy. Also described are processes for respectively: making the semiconductor nanocrystal compound; making the semiconductor nanocrystal probe; and treating materials with the probe.

  1. Surface passivation process of compound semiconductor material using UV photosulfidation

    DOE Patents [OSTI]

    Ashby, Carol I. H. (Edgewood, NM)

    1995-01-01T23:59:59.000Z

    A method for passivating compound semiconductor surfaces by photolytically disrupting molecular sulfur vapor with ultraviolet radiation to form reactive sulfur which then reacts with and passivates the surface of compound semiconductors.

  2. Metal-insulator-semiconductor structures on p-type GaAs with low interface state density

    E-Print Network [OSTI]

    Chen, Zhi

    Metal-insulator-semiconductor structures on p-type GaAs with low interface state density Zhi Chen properties of in situ deposited Si3N4 /Si/p-GaAs metal-insulator-semiconductor structures have been offered by a low gate leakage technology in GaAs, such as metal insulator structures, func- tional Ga

  3. Apparatus for measuring minority carrier lifetimes in semiconductor materials

    DOE Patents [OSTI]

    Ahrenkiel, Richard K. (Lakewood, CO)

    1999-01-01T23:59:59.000Z

    An apparatus for determining the minority carrier lifetime of a semiconductor sample includes a positioner for moving the sample relative to a coil. The coil is connected to a bridge circuit such that the impedance of one arm of the bridge circuit is varied as sample is positioned relative to the coil. The sample is positioned relative to the coil such that any change in the photoconductance of the sample created by illumination of the sample creates a linearly related change in the input impedance of the bridge circuit. In addition, the apparatus is calibrated to work at a fixed frequency so that the apparatus maintains a consistently high sensitivity and high linearly for samples of different sizes, shapes, and material properties. When a light source illuminates the sample, the impedance of the bridge circuit is altered as excess carriers are generated in the sample, thereby producing a measurable signal indicative of the minority carrier lifetimes or recombination rates of the sample.

  4. Improved Thermoelectric Devices: Advanced Semiconductor Materials for Thermoelectric Devices

    SciTech Connect (OSTI)

    None

    2009-12-11T23:59:59.000Z

    Broad Funding Opportunity Announcement Project: Phononic Devices is working to recapture waste heat and convert it into usable electric power. To do this, the company is using thermoelectric devices, which are made from advanced semiconductor materials that convert heat into electricity or actively remove heat for refrigeration and cooling purposes. Thermoelectric devices resemble computer chips, and they manage heat by manipulating the direction of electrons at the nanoscale. These devices aren’t new, but they are currently too inefficient and expensive for widespread use. Phononic Devices is using a high-performance, cost-effective thermoelectric design that will improve the device’s efficiency and enable electronics manufacturers to more easily integrate them into their products.

  5. 1/f noise in semiconductor and metal nanocrystal solids

    SciTech Connect (OSTI)

    Liu, Heng, E-mail: leophy@gmail.com; Lhuillier, Emmanuel, E-mail: emmanuel.lhuillier@espci.fr; Guyot-Sionnest, Philippe [James Franck Institute, The University of Chicago, 929 E 57th Street, Chicago, Illinois 60637 (United States)

    2014-04-21T23:59:59.000Z

    Electrical 1/f noise is measured in thin films of CdSe, CdSe/CdS, ZnO, HgTe quantum dots and Au nanocrystals. The 1/f noise, normalized per nanoparticle, shows no systematic dependence on the nanoparticle material and the coupling material. However, over 10 orders of magnitude, it correlates well with the nearest neighbor conductance suggesting some universal magnitude of the 1/f noise in these granular conductors. In the hopping regime, the main mechanism of 1/f noise is determined to be mobility fluctuated. In the metallic regime obtained with gold nanoparticle films, the noise drops to a similar level as bulk gold films and with a similar temperature dependence.

  6. Coherent ExcitonSurface-Plasmon-Polariton Interaction in Hybrid Metal-Semiconductor Nanostructures

    E-Print Network [OSTI]

    Oldenburg, Carl von Ossietzky Universität

    Coherent Exciton­Surface-Plasmon-Polariton Interaction in Hybrid Metal-Semiconductor Nanostructures 2008; published 8 September 2008) We report measurements of a coherent coupling between surface plasmon when placed close to a metallic nanostructure due to its coupling to surface plasmon polaritons (SPPs

  7. (Data in thousand metric tons of silicon content unless otherwise noted) Domestic Production and Use: Estimated value of silicon alloys and metal (excluding semiconductor-and solar-

    E-Print Network [OSTI]

    Production and Use: Estimated value of silicon alloys and metal (excluding semiconductor- and solar- grade silicon) produced in the United States in 2009 was $470 million. Four companies produced silicon materials in six plants. Of those companies, three produced ferrosilicon in four plants. Metallurgical

  8. Nanocomposite of graphene and metal oxide materials | OSTI, US...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Nanocomposite of graphene and metal oxide materials Re-direct Destination: Nanocomposite materials comprising a metal oxide bonded to at least one graphene material. The...

  9. Isotopically controlled semiconductors

    E-Print Network [OSTI]

    Haller, Eugene E.

    2001-01-01T23:59:59.000Z

    Transmutation Doping of Semiconductor Materials, NationalTransmutation Doping of Semiconductor Materials, NationalProperties of Doped Semiconductors , Solid State Series,

  10. Mechanistic Studies of Charge Injection from Metallic Electrodes into Organic Semiconductors Mediated by Ionic Functionalities: Final Report

    SciTech Connect (OSTI)

    Nguyen, Thuc-Quyen [UCSB; Bazan, Guillermo [UCSB; Mikhailovsky, Alexander [UCSB

    2014-04-15T23:59:59.000Z

    Metal-organic semiconductor interfaces are important because of their ubiquitous role in determining the performance of modern electronics such as organic light emitting diodes (OLEDs), fuel cells, batteries, field effect transistors (FETs), and organic solar cells. Interfaces between metal electrodes required for external wiring to the device and underlying organic structures directly affect the charge carrier injection/collection efficiency in organic-based electronic devices primarily due to the mismatch between energy levels in the metal and organic semiconductor. Environmentally stable and cost-effective electrode materials, such as aluminum and gold typically exhibit high potential barriers for charge carriers injection into organic devices leading to increased operational voltages in OLEDs and FETs and reduced charge extraction in photovoltaic devices. This leads to increased power consumption by the device, reduced overall efficiency, and decreased operational lifetime. These factors represent a significant obstacle for development of next generation of cheap and energy-efficient components based on organic semiconductors. It has been noticed that introduction of organic materials with conjugated backbone and ionic pendant groups known as conjugated poly- and oligoelectrolytes (CPEs and COEs), enables one to reduce the potential barriers at the metal-organic interface and achieve more efficient operation of a device, however exact mechanisms of the phenomenon have not been understood. The goal of this project was to delineate the function of organic semiconductors with ionic groups as electron injection layers. The research incorporated a multidisciplinary approach that encompassed the creation of new materials, novel processing techniques, examination of fundamental electronic properties and the incorporation of the resulting knowledgebase into development of novel organic electronic devices with increased efficiency, environmental stability, and reduced cost. During the execution of the project, main efforts were focused on the synthesis of new charge-bearing organic materials, such as CPEs and COEs, and block copolymers with neutral and ionic segments, studies of mechanisms responsible for the charge injection modulation in devices with ionic interlayers, and use of naturally occurring charged molecules for creation of enhanced devices. The studies allowed PIs to demonstrate the usefulness of the proposed approach for the improvement of operational parameters in model OLED and FET systems resulting in increased efficiency, decreased contact resistance, and possibility to use stable metals for fabrication of device electrodes. The successful proof-of-the-principle results potentially promise development of light-weight, low fabrication cost devices which can be used in consumer applications such as displays, solar cells, and printed electronic devices. Fundamental mechanisms responsible for the phenomena observed have been identified thus advancing the fundamental knowledgebase.

  11. Process for producing chalcogenide semiconductors

    DOE Patents [OSTI]

    Noufi, R.; Chen, Y.W.

    1985-04-30T23:59:59.000Z

    A process for producing chalcogenide semiconductor material is disclosed. The process includes forming a base metal layer and then contacting this layer with a solution having a low pH and containing ions from at least one chalcogen to chalcogenize the layer and form the chalcogenide semiconductor material.

  12. Process for producing chalcogenide semiconductors

    DOE Patents [OSTI]

    Noufi, Rommel (Westminster, CO); Chen, Yih-Wen (Omaha, NE)

    1987-01-01T23:59:59.000Z

    A process for producing chalcogenide semiconductor material is disclosed. The process includes forming a base metal layer and then contacting this layer with a solution having a low pH and containing ions from at least one chalcogen to chalcogenize the layer and form the chalcogenide semiconductor material.

  13. Electrical characterization of native-oxide InAlPGaAs metal-oxide-semiconductor heterostructures using

    E-Print Network [OSTI]

    Electrical characterization of native-oxide InAlPÕGaAs metal-oxide-semiconductor heterostructures 8 December 2003; accepted 20 January 2004 InAIP native oxide/GaAs metal-oxide-semiconductor MOS of Schottky gates can lead to excessive gate leakage current and also restrict the forward gate bias to only

  14. AlGaN/GaN metal-oxide-semiconductor heterostructure field-effect transistors using barium strontium titanate

    E-Print Network [OSTI]

    York, Robert A.

    AlGaN/GaN metal-oxide-semiconductor heterostructure field-effect transistors using barium strontium; published 13 October 2004) Use of high-k gate dielectrics in AlGaN/GaN heterostructure field transconductance and pinchoff voltage. To achieve this, AlGaN/GaN metal-oxide-semiconductor heterostructure field

  15. Evaluation of Novel Semiconductor Materials Potentially Useful in Solar Cells: Cooperative Research and Development Final Report, CRADA number CRD-06-00172

    SciTech Connect (OSTI)

    Geisz, J.

    2010-07-01T23:59:59.000Z

    Evaluation of novel semiconductor materials potentially useful in solar cells. NREL will fabricate, test and analyze solar cells from EpiWorks' wafers produced in 2-3 separate growth campaigns. NREL will also characterize material from 2-3 separate EpiWorks material development campaigns. Finally, NREL will visit EpiWorks and help establish any necessary process, such as spectral CV measurements and III-V on Si metalization processes and help validate solar cell designs and performance.

  16. Apparatus for measuring minority carrier lifetimes in semiconductor materials

    DOE Patents [OSTI]

    Ahrenkiel, R.K.

    1999-07-27T23:59:59.000Z

    An apparatus for determining the minority carrier lifetime of a semiconductor sample includes a positioner for moving the sample relative to a coil. The coil is connected to a bridge circuit such that the impedance of one arm of the bridge circuit is varied as sample is positioned relative to the coil. The sample is positioned relative to the coil such that any change in the photoconductance of the sample created by illumination of the sample creates a linearly related change in the input impedance of the bridge circuit. In addition, the apparatus is calibrated to work at a fixed frequency so that the apparatus maintains a consistently high sensitivity and high linearly for samples of different sizes, shapes, and material properties. When a light source illuminates the sample, the impedance of the bridge circuit is altered as excess carriers are generated in the sample, thereby producing a measurable signal indicative of the minority carrier lifetimes or recombination rates of the sample. 17 figs.

  17. Porous Materials -Metal-Organic Frameworks

    E-Print Network [OSTI]

    Tsymbal, Evgeny Y.

    ShellsSnow Coral SoilBoneLungs Lemons #12;Artificial Porous Materials Insulation Cake Concrete BreadPorous Materials -Metal-Organic Frameworks 2012 Nanocamp NCMN, UNL Dr. Jian Zhang & Jacob Johnson-organic Frameworks Porous polymer networks #12;Porous Materials in Nature Sandstones Sea Sponge Butterfly Wings Egg

  18. HIGH-K-INAS METAL-OXIDE-SEMICONDUCTOR CAPACITORS FORMED BY ATOMIC-LAYER DEPOSITION

    E-Print Network [OSTI]

    -k-InAs metal-oxide-semiconductor capacitors. Devices are formed using various substrate pretreatments, film by the Terman method to be in the 1013 cm-2 -eV-1 range at midgap. TEM and XPS data suggest the high trap

  19. Compositions of doped, co-doped and tri-doped semiconductor materials

    DOE Patents [OSTI]

    Lynn, Kelvin (Pullman, WA; , Jones, Kelly (Colfax, WA); Ciampi, Guido (Watertown, MA)

    2011-12-06T23:59:59.000Z

    Semiconductor materials suitable for being used in radiation detectors are disclosed. A particular example of the semiconductor materials includes tellurium, cadmium, and zinc. Tellurium is in molar excess of cadmium and zinc. The example also includes aluminum having a concentration of about 10 to about 20,000 atomic parts per billion and erbium having a concentration of at least 10,000 atomic parts per billion.

  20. Mismatched semiconductor nanowires: growth and characterization

    E-Print Network [OSTI]

    Yim, Joanne Wing Lan

    2011-01-01T23:59:59.000Z

    SemiconductorFundamentals of Semiconductors: Physics and MaterialsDilute III-V Nitride Semiconductors and Material Systems (

  1. Using a Semiconductor-to-Metal Transition to Control Optical Transmission through Subwavelength Hole Arrays

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Donev, E. U.; Suh, J. Y.; Lopez, R.; Feldman, L. C.; Haglund, R. F.

    2008-01-01T23:59:59.000Z

    We describe a simple configuration in which the extraordinary optical transmission effect through subwavelength hole arrays in noble-metal films can be switched by the semiconductor-to-metal transition in an underlying thin film of vanadium dioxide. In these experiments, the transition is brought about by thermal heating of the bilayer film. The surprising reverse hysteretic behavior of the transmission through the subwavelength holes in the vanadium oxide suggest that this modulation is accomplished by a dielectric-matching condition rather than plasmon coupling through the bilayer film. The results of this switching, including the wavelength dependence, are qualitatively reproduced by a transfer matrix model.more »The prospects for effecting a similar modulation on a much faster time scale by using ultrafast laser pulses to trigger the semiconductor-to-metal transition are also discussed.« less

  2. Intrazeolite metal carbonyl phototopotaxy: From Tungsten(VI) oxide quantum dots to a zero-dimensional semiconductor quantum supralattice

    SciTech Connect (OSTI)

    Ozin, G.A.; Oezkar, S. (Univ. of Toronto, Ontario (Canada))

    1990-09-20T23:59:59.000Z

    Attention is focused on the use of simple binary metal carbonyls for the nucleation, growth, and stabilization of intrazeolite semiconductor quantum nanostructures. The rationale for selecting this particular group of precursor molecules relates to their volatility, molecular dimensions, ease of purification, availability, and facile and quantitative conversion to the respective metal oxide materials with minimal contamination by carbon. In this study the intrazeolite photooxidation chemistry of {alpha}-cage encapsulated hexacarbonyltungsten(0) in Na{sub 56}Y and H{sub 56}Y, n(W(CO){sub 6})-Na{sub 56}Y(H{sub 56}Y), with O{sub 2} provides a novel synthetic pathway to {alpha}-cage-located tungsten(VI) oxide n(WO{sub 3})-Na{sub 56}Y(H{sub 56}Y) intrazeolite quantum dots and a zero-dimensional semiconductor quantum supralattice (where n = 0-32), which might find applications as new solid-state materials for use in quantum electronic and nonlinear optic devices.

  3. Nanocomposites of Semimetallic ErAs Nanoparticles Epitaxially Embedded within InGaAlAs-based Semiconductors for Thermoelectric Materials

    E-Print Network [OSTI]

    GaAlAs-based Semiconductors for Thermoelectric Materials J.M.O. Zide', G. Zeng2, J.H. Bahk2, W. Kim3, S. L. Singer3, DAs nanoparticles which are epitaxially embedded within InGaAlAs-based semiconductors. The properties. In one geometry, barriers of InGaAlAs, a wider bandgap semiconductor, are introduced into an Er

  4. Toward Photochemical Water Splitting Using Band-Gap-Narrowed Semiconductors and Transition-Metal Based Molecular Catalysts

    SciTech Connect (OSTI)

    Muckerman,J.T.; Rodriguez, J.A.; Fujita, E.

    2009-06-07T23:59:59.000Z

    We are carrying out coordinated theoretical and experimental studies of toward photochemical water splitting using band-gap-narrowed semiconductors (BGNSCs) with attached multi-electron molecular water oxidation and hydrogen production catalysts. We focus on the coupling between the materials properties and the H{sub 2}O redox chemistry, with an emphasis on attaining a fundamental understanding of the individual elementary steps in the following four processes: (1) Light-harvesting and charge-separation of stable oxide or oxide-derived semiconductors for solar-driven water splitting, including the discovery and characterization of the behavior of such materials at the aqueous interface; (2) The catalysis of the four-electron water oxidation by dinuclear hydroxo transition-metal complexes with quinonoid ligands, and the rational search for improved catalysts; (3) Transfer of the design principles learned from the elucidation of the DuBois-type hydrogenase model catalysts in acetonitrile to the rational design of two-electron hydrogen production catalysts for aqueous solution; (4) Combining these three elements to examine the function of oxidation catalysts on BGNSC photoanode surfaces and hydrogen production catalysts on cathode surfaces at the aqueous interface to understand the challenges to the efficient coupling of the materials functions.

  5. Effect of Temperature on GaGdO/GaN Metal Oxide Semiconductor Field Effect Transistors

    SciTech Connect (OSTI)

    Abernathy, C.R.; Baca, A.; Chu, S.N.G.; Hong, M.; Lothian, J.R.; Marcus, M.A.; Pearton, S.J.; Ren, F.; Schurman, M.J.

    1998-10-14T23:59:59.000Z

    GaGdO was deposited on GaN for use as a gate dielectric in order to fabricate a depletion metal oxide semiconductor field effect transistor (MOSFET). This is the fmt demonstration of such a device in the III-Nitride system. Analysis of the effect of temperature on the device shows that gate leakage is significantly reduced at elevated temperature relative to a conventional metal semiconductor field effeet transistor (MESFET) fabricated on the same GaN layer. MOSFET device operation in fact improved upon heating to 400 C. Modeling of the effeet of temperature on contact resistance suggests that the improvement is due to a reduction in the parasitic resistances present in the device.

  6. Sandia National Laboratories: metal-organic framework materials

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    metal-organic framework materials Combining 'Tinkertoy' Materials with Solar Cells for Increased Photovoltaic Efficiency On December 4, 2014, in Energy, Materials Science, News,...

  7. Optical limiting of layered transition metal dichalcogenide semiconductors

    E-Print Network [OSTI]

    Dong, Ningning; Feng, Yanyan; Zhang, Saifeng; Zhang, Xiaoyan; Chang, Chunxia; Fan, Jintai; Zhang, Long; Wang, Jun

    2015-01-01T23:59:59.000Z

    Nonlinear optical property of transition metal dichalcogenide (TMDC) nanosheet dispersions, including MoS2, MoSe2, WS2, and WSe2, was performed by using Z-scan technique with ns pulsed laser at 1064 nm and 532 nm. The results demonstrate that the TMDC dispersions exhibit significant optical limiting response at 1064 nm due to nonlinear scattering, in contrast to the combined effect of both saturable absorption and nonlinear scattering at 532 nm. Selenium compounds show better optical limiting performance than that of the sulfides in the near infrared. A liquid dispersion system based theoretical modelling is proposed to estimate the number density of the nanosheet dispersions, the relationship between incident laser fluence and the size of the laser generated micro-bubbles, and hence the Mie scattering-induced broadband optical limiting behavior in the TMDC dispersions.

  8. Metal Oxide Semiconductor Nanoparticles Pave the Way for Medical Innovation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHighand Retrievals from aRod EggertMercuryAdvanced MaterialsPortal-

  9. Antiferromagnetic exchange bias of a ferromagnetic semiconductor by a ferromagnetic metal

    E-Print Network [OSTI]

    Olejnik, K.

    2010-01-01T23:59:59.000Z

    exchange bias of a magnetic semiconductor by a magneticexchange bias in the magnetic semiconductor. The shape and

  10. All-Metallic Vertical Transistors Based on Stacked Dirac Materials

    E-Print Network [OSTI]

    Wang, Yangyang

    It is an ongoing pursuit to use metal as a channel material in a field effect transistor. All metallic transistor can be fabricated from pristine semimetallic Dirac materials (such as graphene, silicene, and germanene), ...

  11. Hydrogenated Bilayer Wurtzite SiC Nanofilms: A Two-Dimensional Bipolar Magnetic Semiconductor Material

    E-Print Network [OSTI]

    Yuan, Long; Yang, Jinlong

    2012-01-01T23:59:59.000Z

    Recently, a new kind of spintronics materials, bipolar magnetic semiconductor (BMS), has been proposed. The spin polarization of BMS can be conveniently controlled by a gate voltage, which makes it very attractive in device engineering. Now, the main challenge is finding more BMS materials. In this article, we propose that hydrogenated wurtzite SiC nanofilm is a two-dimensional BMS material. Its BMS character is very robust under the effect of strain, substrate, or even a strong electric field. The proposed two-dimensional BMS material paves the way to use this promising new material in an integrated circuit.

  12. Disordered electronic and magnetic systems - transition metal (Mn) and rare earth (Gd) doped amorphous group IV semiconductors (C, Si, Ge)

    E-Print Network [OSTI]

    Zeng, Li

    2007-01-01T23:59:59.000Z

    1.1 Magnetic Semiconductors . . . . . . . . . . . . . . .Semiconductors . . . . . . . . . . . . . . . . . . . 1.3in Semiconductors . . . . . . . . . . . . . . . . . . 1.3.5

  13. Amorphous silicon enhanced metal-insulator-semiconductor contacts for silicon solar cells

    SciTech Connect (OSTI)

    Bullock, J., E-mail: james.bullock@anu.edu.au; Cuevas, A.; Yan, D. [Research School of Engineering, The Australian National University, Canberra, ACT 0200 (Australia); Demaurex, B.; Hessler-Wyser, A.; De Wolf, S. [Ecole Polytechnique Fédérale de Lausanne (EPFL), Institute of Micro Engineering (IMT), Photovoltaics and Thin Film Electronic Laboratory PVLab, Maladière 71b, CH-200 Neuchâtel (Switzerland)

    2014-10-28T23:59:59.000Z

    Carrier recombination at the metal-semiconductor contacts has become a significant obstacle to the further advancement of high-efficiency diffused-junction silicon solar cells. This paper provides the proof-of-concept of a procedure to reduce contact recombination by means of enhanced metal-insulator-semiconductor (MIS) structures. Lightly diffused n{sup +} and p{sup +} surfaces are passivated with SiO{sub 2}/a-Si:H and Al{sub 2}O{sub 3}/a-Si:H stacks, respectively, before the MIS contacts are formed by a thermally activated alloying process between the a-Si:H layer and an overlying aluminum film. Transmission/scanning transmission electron microscopy (TEM/STEM) and energy dispersive x-ray spectroscopy are used to ascertain the nature of the alloy. Idealized solar cell simulations reveal that MIS(n{sup +}) contacts, with SiO{sub 2} thicknesses of ?1.55?nm, achieve the best carrier-selectivity producing a contact resistivity ?{sub c} of ?3 m? cm{sup 2} and a recombination current density J{sub 0c} of ?40 fA/cm{sup 2}. These characteristics are shown to be stable at temperatures up to 350?°C. The MIS(p{sup +}) contacts fail to achieve equivalent results both in terms of thermal stability and contact characteristics but may still offer advantages over directly metallized contacts in terms of manufacturing simplicity.

  14. Production of pulsed, mass-selected beams of metal and semiconductor clusters

    SciTech Connect (OSTI)

    Kamalou, Omar; Rangama, Jimmy; Ramillon, Jean-Marc; Guinement, Patrick; Huber, Bernd A. [CIMAP, CEA-CNRS-ENSICaen-UCBN, Bv. Henry Becquerel (B.P. 5133), F-14070 Caen Cedex 05 (France)

    2008-06-15T23:59:59.000Z

    We report on the development of a beam line for mass-selected metal and semiconductor clusters. The cluster source combines the principles of plasma sputtering and gas condensation. Both techniques together allow to produce clusters in a wide size range. With the aid of a time-of-flight system, small clusters (i.e., Cu{sub n}{sup +}, n<100) are selected and pure beams containing only one cluster size are provided. For large clusters (containing several thousands of atoms), a beam with a narrow size distribution is obtained. A 90 deg. quadrupole deviator is used to separate charged clusters from neutral ones.

  15. Chemical dynamics and bonding at gas/semiconductor and oxide/semiconductor interfaces

    E-Print Network [OSTI]

    Bishop, Sarah R.

    2010-01-01T23:59:59.000Z

    applied to alternative semiconductor materials to determinephase oxides and semiconductor surfaces. Both experimentalunderstanding of the oxide/semiconductor interface. The

  16. System for characterizing semiconductor materials and photovoltaic device

    DOE Patents [OSTI]

    Sopori, B.L.

    1996-12-03T23:59:59.000Z

    Apparatus for detecting and mapping defects in the surfaces of polycrystalline material in a manner that distinguishes dislocation pits from grain boundaries includes a first laser of a first wavelength for illuminating a wide spot on the surface of the material, a second laser of a second relatively shorter wavelength for illuminating a relatively narrower spot on the surface of the material, a light integrating sphere with apertures for capturing light scattered by etched dislocation pits in an intermediate range away from specular reflection while allowing light scattered by etched grain boundaries in a near range from specular reflection to pass through, and optical detection devices for detecting and measuring intensities of the respective intermediate scattered light and near specular scattered light. A center blocking aperture or filter can be used to screen out specular reflected light, which would be reflected by nondefect portions of the polycrystalline material surface. An X-Y translation stage for mounting the polycrystalline material and signal processing and computer equipment accommodate raster mapping, recording, and displaying of respective dislocation and grain boundary defect densities. A special etch procedure is included, which prepares the polycrystalline material surface to produce distinguishable intermediate and near specular light scattering in patterns that have statistical relevance to the dislocation and grain boundary defect densities. A reflectance measurement of the piece of material is obtained by adding together the signals from the optical detection devices. In the case where the piece of material includes a photovoltaic device, the current induced in the device by the illuminating light can be measured with a current sensing amplifier after the light integrating sphere is moved away from the device. 22 figs.

  17. Hydrogen in semiconductors and insulators

    E-Print Network [OSTI]

    Van de Walle, Chris G.

    2007-01-01T23:59:59.000Z

    level in two different semiconductors, illustrating the06-01999R1 Hydrogen in semiconductors and insulators SpecialA. oxide materials; A. semiconductors; C. electronic

  18. DISSOLUTION OF FISSILE MATERIALS CONTAINING TANTALUM METAL

    SciTech Connect (OSTI)

    Rudisill, T; Mark Crowder, M; Michael Bronikowski, M

    2007-05-29T23:59:59.000Z

    The dissolution of composite materials containing plutonium (Pu) and tantalum (Ta) metals is currently performed in Phase I of the HB-Line facility. The conditions for the present flowsheet are the dissolution of 500 g of Pu metal in the 15 L dissolver using a 4 M nitric acid (HNO{sub 3}) solution containing 0.2 M potassium fluoride (KF) at 95 C for 4-6 h.[1] The Ta metal, which is essentially insoluble in HNO{sub 3}/fluoride solutions, is rinsed with process water to remove residual acid, and then burned to destroy classified information. During the initial dissolution campaign, the total mass of Pu and Ta in the dissolver charge was limited to nominally 300 g. The reduced amount of Pu in the dissolver charge coupled with significant evaporation of solution during processing of several dissolver charges resulted in the precipitation of a fluoride salt contain Pu. Dissolution of the salt required the addition of aluminum nitrate (Al(NO{sub 3}){sub 3}) and a subsequent undesired 4 h heating cycle. As a result of this issue, HB-Line Engineering requested the Savannah River National Laboratory (SRNL) to optimize the dissolution flowsheet to reduce the cycle time, reduce the risk of precipitating solids, and obtain hydrogen (H{sub 2}) generation data at lower fluoride concentrations.[2] Using samples of the Pu/Ta composite material, we performed three experiments to demonstrate the dissolution of the Pu metal using HNO{sub 3} solutions containing 0.15 and 0.175 M KF. When 0.15 M KF was used in the dissolving solution, 95.5% of the Pu in the sample dissolved in approximately 6 h. The undissolved material included a small amount of Pu metal and plutonium oxide (PuO{sub 2}) solids. Complete dissolution of the metal would have likely occurred if the dissolution time had been extended. This assumption is based on the steady increase in the Pu concentration observed during the last several hours of the experiment. We attribute the formation of PuO{sub 2} to the complexation of fluoride by the Pu. The fluoride became unavailable to catalyze the dissolution of PuO{sub 2} as it formed on the surface of the metal. The mass of Pu dissolved is equivalent to the dissolution of 343 g of Pu in the HB-Line dissolvers. In the initial experiment with 0.175 M KF in the solution, we achieved complete dissolution of the Pu in 6 h. The mass of Pu dissolved scales to the dissolution of 358 g of Pu in the HB-Line dissolvers. The second experiment using 0.175 M KF was terminated after approximately 6 h following the dissolution of 92.7% of the Pu in the sample; however, dissolution of additional Pu was severely limited due to the slow dissolution rate observed beyond approximately 4 h. A small amount of PuO{sub 2} was also produced in the solution. The slow rate of dissolution was attributed to the diminishing surface area of the Pu and a reduction in the fluoride activity due to complexation with Pu. Given time (>4 h), the Pu metal may have dissolved using the original solution or a significant portion may have oxidized to PuO{sub 2}. If the metal oxidized to PuO{sub 2}, we expect little of the material would have dissolved due to the fluoride complexation and the low HNO{sub 3} concentration. The mass of Pu dissolved in the second experiment scales to the dissolution of 309 g of Pu in the HB-Line dissolvers. Based on the data from the Pu/Ta dissolution experiments we recommend the use of 4 M HNO{sub 3} containing 0.175 M KF for the dissolution of 300 g of Pu metal in the 15 L HB-Line dissolver. A dissolution temperature of nominally 95 C should allow for essentially complete dissolution of the metal in 6 h. Although the H{sub 2} concentration in the offgas from the experiments was at or below the detection limit of the gas chromatograph (GC) used in these experiments, small concentrations (<3 vol %) of H{sub 2} are typically produced in the offgas during Pu metal dissolutions. Therefore, appropriate controls must be established to address the small H{sub 3} generation rates in accordance with this work and the earlier flowsheet demonstrated

  19. Material accountancy for metallic fuel pin casting

    SciTech Connect (OSTI)

    Bucher, R.G.; Orechwa, Y.; Beitel, J.C.

    1995-08-01T23:59:59.000Z

    The operation of the Fuel Conditioning Facility (FCF) is based on the electrometallurgical processing of spent metallic reactor fuel. The pin casting operation, although only one of several operations in FCF, was the first to be on-line. As such, it has served to demonstrate the material accountancy system in many of its facets. This paper details, for the operation of the pin casting process with depleted uranium, the interaction between the mass tracking system (MTG) and some of the ancillary computer codes which generate pertinent information for operations and material accountancy. It is necessary to distinguish between two types of material balance calculations -- closeout for operations and material accountancy for safeguards. The two have much in common, for example, the mass tracking system database and the calculation of an inventory difference, but, in general, are not congruent with regard to balance period and balance spatial domain. Moreover, the objective, assessment, and reporting requirements of the calculated inventory difference are very different in the two cases.

  20. Hydrocarbon reaction with HF-cleaned Si(lOQ) and effects on metal-oxide-semiconductor device quality

    E-Print Network [OSTI]

    Rubloff, Gary W.

    Hydrocarbon reaction with HF-cleaned Si(lOQ) and effects on metal-oxide-semiconductor device-cleaned Si( 100) towards hydrocarbon adsorption is examined by surface analysis; most hydrocarbons adsorb oxidation after HF treatment.4'5 In this letter, passivation against hydrocarbon contamination is studied

  1. Controlling Graphene Ultrafast Hot Carrier Response from Metal-like to Semiconductor-like by Electrostatic Gating

    E-Print Network [OSTI]

    Zettl, Alex

    with dry nitrogen during the measurement. Sample preparation We grow single layer graphene on copper foil1 Controlling Graphene Ultrafast Hot Carrier Response from Metal-like to Semiconductor electro-optic sampling.2 The focused THz beam at our graphene sample has a diameter of 1 mm. For optical

  2. AlGaN/GaN Metal Oxide Semiconductor Field Effect Transistors using Titanium Dioxide P. J. HANSEN

    E-Print Network [OSTI]

    York, Robert A.

    AlGaN/GaN Metal Oxide Semiconductor Field Effect Transistors using Titanium Dioxide P. J. HANSEN 1 epitaxially on AlGaN/GaN HFET structures by molecular beam epitaxy (MBE). Growth was first performed on GaN templates to establish epitaxial growth conditions. X-ray diffraction showed [001] TiO2 || [1010]GaN

  3. Super-Resolution Mapping of Photogenerated Electron and Hole Separation in Single Metal-Semiconductor Nanocatalysts

    SciTech Connect (OSTI)

    Ha, Ji Won [Ames Laboratory; Ruberu, T. Purnima A. [Ames Laboratory; Han, Rui [Ames Laboratory; Dong, Bin [Ames Laboratory; Vela, Javier [Ames Laboratory; Fang, Ning [Ames Laboratory

    2014-01-12T23:59:59.000Z

    Metal–semiconductor heterostructures are promising visible light photocatalysts for many chemical reactions. Here, we use high-resolution superlocalization imaging to reveal the nature and photocatalytic properties of the surface reactive sites on single Au–CdS hybrid nanocatalysts. We experimentally reveal two distinct, incident energy-dependent charge separation mechanisms that result in completely opposite photogenerated reactive sites (e– and h+) and divergent energy flows on the hybrid nanocatalysts. We find that plasmon-induced hot electrons in Au are injected into the conduction band of the CdS semiconductor nanorod. The specifically designed Au-tipped CdS heterostructures with a unique geometry (two Au nanoparticles at both ends of each CdS nanorod) provide more convincing high-resolution single-turnover mapping results and clearly prove the two charge separation mechanisms. Engineering the direction of energy flow at the nanoscale can provide an efficient way to overcome important challenges in photocatalysis, such as controlling catalytic activity and selectivity. These results bear enormous potential impact on the development of better visible light photocatalysts for solar-to-chemical energy conversion.

  4. Stabilized Lithium Metal Powder, Enabling Material and Revolutionary...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Peer Evaluation es011yakovleva2011p.pdf More Documents & Publications Stabilized Lithium Metal Powder, Enabling Material and Revolutionary Technology for High Energy Li-ion...

  5. Sharp semiconductor-to-metal transition of VO{sub 2} thin films on glass substrates

    SciTech Connect (OSTI)

    Jian, Jie; Chen, Aiping [Department of Electrical and Computer Engineering, Texas A and M University, College Station, Texas 77843-3128 (United States); Zhang, Wenrui [Material Science and Engineering Program, Texas A and M University, College Station, Texas 77843-3128 (United States); Wang, Haiyan, E-mail: wangh@ece.tamu.edu [Department of Electrical and Computer Engineering, Texas A and M University, College Station, Texas 77843-3128 (United States); Material Science and Engineering Program, Texas A and M University, College Station, Texas 77843-3128 (United States)

    2013-12-28T23:59:59.000Z

    Outstanding phase transition properties of vanadium dioxide (VO{sub 2}) thin films on amorphous glass were achieved and compared with the ones grown on c-cut sapphire and Si (111) substrates, all by pulsed laser deposition. The films on glass substrate exhibit a sharp semiconductor-to-metal transition (?4.3?°C) at a near bulk transition temperature of ?68.4?°C with an electrical resistance change as high as 3.2?×?10{sup 3} times. The excellent phase transition properties of the films on glass substrate are correlated with the large grain size and low defects density achieved. The phase transition properties of VO{sub 2} films on c-cut sapphire and Si (111) substrates were found to be limited by the high defect density.

  6. Strongly modified four-wave mixing in a coupled semiconductor quantum dot-metal nanoparticle system

    SciTech Connect (OSTI)

    Paspalakis, Emmanuel, E-mail: paspalak@upatras.gr [Materials Science Department, School of Natural Sciences, University of Patras, 265 04 Patras (Greece); Evangelou, Sofia [Materials Science Department, School of Natural Sciences, University of Patras, 265 04 Patras (Greece); Department of Materials Science and Engineering, University of Ioannina, Ioannina 45110 (Greece); Kosionis, Spyridon G.; Terzis, Andreas F. [Department of Physics, School of Natural Sciences, University of Patras, 265 04 Patras (Greece)

    2014-02-28T23:59:59.000Z

    We study the four-wave mixing effect in a coupled semiconductor quantum dot-spherical metal nanoparticle structure. Depending on the values of the pump field intensity and frequency, we find that there is a critical distance that changes the form of the spectrum. Above this distance, the four-wave mixing spectrum shows an ordinary three-peaked form and the effect of controlling its magnitude by changing the interparticle distance can be obtained. Below this critical distance, the four-wave mixing spectrum becomes single-peaked; and as the interparticle distance decreases, the spectrum is strongly suppressed. The behavior of the system is explained using the effective Rabi frequency that creates plasmonic metaresonances in the hybrid structure. In addition, the behavior of the effective Rabi frequency is explained via an analytical solution of the density matrix equations.

  7. Proton-induced transient effects in a metal-semiconductor-metal (MSM) photodetector for optical-based data transfer

    SciTech Connect (OSTI)

    Marshall, C.J. [NASA/GSFC, Greenbelt, MD (United States)] [NASA/GSFC, Greenbelt, MD (United States); [NRL, Washington, DC (United States); Marshall, P.W.; Carts, M.A. [NRL, Washington, DC (United States)] [NRL, Washington, DC (United States); [SFA, Largo, MD (United States); Reed, R.A.; LaBel, K.A. [NASA/GSFC, Greenbelt, MD (United States)] [NASA/GSFC, Greenbelt, MD (United States)

    1998-12-01T23:59:59.000Z

    The authors present a study of proton transient effects in metal-semiconductor-metal (MSM) photodetectors, which demonstrates their inherent advantage for minimizing Single Event Effects (SEEs) in proton environments. Upset mechanisms are characterized for 830 nm GaAs and 1300 nm InGaAs detectors. Only protons incident at grazing angles are likely to cause a bit errors by direct ionization. The MSM technology appears to be a more robust to single bit errors than thicker 1300 nm p-i-n diode structures which the authors have previously shown to be susceptible to errors from direct ionization events at all angles, and also are relatively high optical powders. For a given receiver, the relative contributions of direct ionization and nuclear reaction upset mechanisms at a specific data rate and optical power are determined by the geometry of the charge collection volume of the detector. The authors show that state-of-the-art p-i-n detectors can also display a reduced sensitivity to direct ionization by incident protons except at grazing angles.

  8. Wafer-fused semiconductor radiation detector

    DOE Patents [OSTI]

    Lee, Edwin Y. (Livermore, CA); James, Ralph B. (Livermore, CA)

    2002-01-01T23:59:59.000Z

    Wafer-fused semiconductor radiation detector useful for gamma-ray and x-ray spectrometers and imaging systems. The detector is fabricated using wafer fusion to insert an electrically conductive grid, typically comprising a metal, between two solid semiconductor pieces, one having a cathode (negative electrode) and the other having an anode (positive electrode). The wafer fused semiconductor radiation detector functions like the commonly used Frisch grid radiation detector, in which an electrically conductive grid is inserted in high vacuum between the cathode and the anode. The wafer-fused semiconductor radiation detector can be fabricated using the same or two different semiconductor materials of different sizes and of the same or different thicknesses; and it may utilize a wide range of metals, or other electrically conducting materials, to form the grid, to optimize the detector performance, without being constrained by structural dissimilarity of the individual parts. The wafer-fused detector is basically formed, for example, by etching spaced grooves across one end of one of two pieces of semiconductor materials, partially filling the grooves with a selected electrical conductor which forms a grid electrode, and then fusing the grooved end of the one semiconductor piece to an end of the other semiconductor piece with a cathode and an anode being formed on opposite ends of the semiconductor pieces.

  9. Metal-semiconductor-transition observed in Bi{sub 2}Ca(Sr, Ba){sub 2}Co{sub 2}O{sub 8+?} single crystals

    SciTech Connect (OSTI)

    Dong, Song-Tao [National Laboratory of Solid State Microstructures and Department of Material Science and Engineering, Nanjing University, Nanjing 210093 (China); Institute of Material Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003 (China); Zhang, Bin-Bin; Zhang, Lun-Yong; Yao, Shu-Hua, E-mail: ybchen@nju.edu.cn, E-mail: shyao@nju.edu.cn; Zhou, Jian; Zhang, Shan-Tao; Gu, Zheng-Bin; Chen, Yan-Feng [National Laboratory of Solid State Microstructures and Department of Material Science and Engineering, Nanjing University, Nanjing 210093 (China); Chen, Y. B., E-mail: ybchen@nju.edu.cn, E-mail: shyao@nju.edu.cn [National Laboratory of Solid State Microstructures and Department of Physics and National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093 (China)

    2014-07-28T23:59:59.000Z

    Electrical property evolution of Bi{sub 2}AE{sub 2}Co{sub 2}O{sub 8+?} single crystals (AE?=?Ca, Sr and Ba) is systematically explored. When AE changes from Ca to Ba, the electrical property of Bi{sub 2}Ca{sub 2}Co{sub 2}O{sub 8+?} and Bi{sub 2}Sr{sub 2}Co{sub 2}O{sub 8+?} demonstrates semiconductor-like properties. But Bi{sub 2}Ba{sub 2}Co{sub 2}O{sub 8+?} shows the metallic behavior. Analysis of temperature-dependent resistance substantiates that from metallic Bi{sub 2}Ba{sub 2}Co{sub 2}O{sub 8+?} to semiconductor-like Bi{sub 2}Sr{sub 2}Co{sub 2}O{sub 8+?} can be attributed to Anderson localization. However the semiconductor behaviour of Bi{sub 2}Sr{sub 2}Co{sub 2}O{sub 8+?} and Bi{sub 2}Ca{sub 2}Co{sub 2}O{sub 8+?} is related to electronic correlations effect that is inferred by large negative magnetoresistance (?70%). The theoretical electronic structures and valence X-ray photoemission spectroscopy substantiate that there is a relative large density of state around Fermi level in Bi{sub 2}Ba{sub 2}Co{sub 2}O{sub 8+?} compared with other two compounds. It suggests that Bi{sub 2}Ba{sub 2}Co{sub 2}O{sub 8+?} is more apt to be metal in this material system.

  10. Wide-bandgap semiconductors for high power, high frequency and high temperature. Materials Research Society symposium proceedings Volume 512

    SciTech Connect (OSTI)

    DenBaars, S.; Palmour, J.; Shur, M.; Spencer, M. [eds.

    1997-07-01T23:59:59.000Z

    Wide-bandgap semiconductors have a long and illustrious history, starting with the first paper on SiC light-emitting diodes published in 1907. In the last few years, however, interest in wide-bandgap semiconductors has skyrocketed. Improved material quality, important breakthroughs both in SiC and GaN technologies, and the emergence of blue GaN-based lasers, have stimulated this progress. To provide a fairly complete and up-to-date picture of this important field, most of the work presented at the conference is included in the volume. In addition, invited papers present an excellent overview of the current state of the art and offer projections for future developments. Topics include: GaN materials and devices; crystal growth; SiC materials and devices; characterization of wide-bandgap semiconductors; and processing characterization and properties of wide-bandgap materials.

  11. Method to determine the position-dependant metal correction factor for dose-rate equivalent laser testing of semiconductor devices

    DOE Patents [OSTI]

    Horn, Kevin M.

    2013-07-09T23:59:59.000Z

    A method reconstructs the charge collection from regions beneath opaque metallization of a semiconductor device, as determined from focused laser charge collection response images, and thereby derives a dose-rate dependent correction factor for subsequent broad-area, dose-rate equivalent, laser measurements. The position- and dose-rate dependencies of the charge-collection magnitude of the device are determined empirically and can be combined with a digital reconstruction methodology to derive an accurate metal-correction factor that permits subsequent absolute dose-rate response measurements to be derived from laser measurements alone. Broad-area laser dose-rate testing can thereby be used to accurately determine the peak transient current, dose-rate response of semiconductor devices to penetrating electron, gamma- and x-ray irradiation.

  12. Solid materials for removing metals and fabrication method

    DOE Patents [OSTI]

    Coronado, Paul R.; Reynolds, John G.; Coleman, Sabre J.

    2004-10-19T23:59:59.000Z

    Solid materials have been developed to remove contaminating metals and organic compounds from aqueous media. The contaminants are removed by passing the aqueous phase through the solid materials which can be in molded, granular, or powder form. The solid materials adsorb the metals and the organics leaving a purified aqueous stream. The materials are sol-gel and or sol-gel and granulated activated carbon (GAC) mixtures. The species-specific adsorption occurs through specific chemical modifications of the solids tailored towards the contaminant(s). The contaminated solid materials can then be disposed of or the contaminant can be removed and the solids recycled.

  13. alignment material properties: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    the thermoelectric proper- ties of VSSL structures using Walker, D. Greg 9 Composite THz materials using aligned metallic and semiconductor microwires, experiments and...

  14. Method for manufacturing electrical contacts for a thin-film semiconductor device

    DOE Patents [OSTI]

    Carlson, David E. (Yardley, PA); Dickson, Charles R. (Pennington, NJ); D'Aiello, Robert V. (East Brunswick, NJ)

    1988-11-08T23:59:59.000Z

    A method of fabricating spaced-apart back contacts on a thin film of semiconductor material by forming strips of buffer material on top of the semiconductor material in locations corresponding to the desired dividing lines between back contacts, forming a film of metal substantially covering the semiconductor material and buffer strips, and scribing portions of the metal film overlying the buffer strips with a laser without contacting the underlying semiconductor material to separate the metal layer into a plurality of back contacts. The buffer material serves to protect the underlying semiconductor material from being damaged during the laser scribing. Back contacts and multi-cell photovoltaic modules incorporating such back contacts also are disclosed.

  15. Diamond logic inverter with enhancement-mode metal-insulator-semiconductor field effect transistor

    SciTech Connect (OSTI)

    Liu, J. W., E-mail: liu.jiangwei@nims.go.jp [International Center for Young Scientists (ICYS), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Liao, M. Y.; Imura, M. [Optical and Electronic Materials Unit, NIMS, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Watanabe, E.; Oosato, H. [Nanofabrication Platform, NIMS, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Koide, Y., E-mail: koide.yasuo@nims.go.jp [Optical and Electronic Materials Unit, NIMS, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Nanofabrication Platform, NIMS, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Center of Materials Research for Low Carbon Emission, NIMS, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

    2014-08-25T23:59:59.000Z

    A diamond logic inverter is demonstrated using an enhancement-mode hydrogenated-diamond metal-insulator-semiconductor field effect transistor (MISFET) coupled with a load resistor. The gate insulator has a bilayer structure of a sputtering-deposited LaAlO{sub 3} layer and a thin atomic-layer-deposited Al{sub 2}O{sub 3} buffer layer. The source-drain current maximum, extrinsic transconductance, and threshold voltage of the MISFET are measured to be ?40.7?mA·mm{sup ?1}, 13.2?±?0.1?mS·mm{sup ?1}, and ?3.1?±?0.1?V, respectively. The logic inverters show distinct inversion (NOT-gate) characteristics for input voltages ranging from 4.0 to ?10.0?V. With increasing the load resistance, the gain of the logic inverter increases from 5.6 to as large as 19.4. The pulse response against the high and low input voltages shows the inversion response with the low and high output voltages.

  16. Cermet materials prepared by combustion synthesis and metal infiltration

    DOE Patents [OSTI]

    Holt, Joseph B. (San Jose, CA); Dunmead, Stephen D. (Davis, CA); Halverson, Danny C. (Modesto, CA); Landingham, Richard L. (Livermore, CA)

    1991-01-01T23:59:59.000Z

    Ceramic-metal composites (cermets) are made by a combination of self-propagating high temperature combustion synthesis and molten metal infiltration. Solid-gas, solid-solid and solid-liquid reactions of a powder compact produce a porous ceramic body which is infiltrated by molten metal to produce a composite body of higher density. AlN-Al and many other materials can be produced.

  17. Cermet materials prepared by combustion synthesis and metal infiltration

    DOE Patents [OSTI]

    Holt, J.B.; Dunmead, S.D.; Halverson, D.C.; Landingham, R.L.

    1991-01-29T23:59:59.000Z

    Ceramic-metal composites (cermets) are made by a combination of self-propagating high temperature combustion synthesis and molten metal infiltration. Solid-gas, solid-solid and solid-liquid reactions of a powder compact produce a porous ceramic body which is infiltrated by molten metal to produce a composite body of higher density. AlN-Al and many other materials can be produced. 6 figures.

  18. Nanoporous Metal-Inorganic Materials for Storage and Capture...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Vehicles and Fuels Vehicles and Fuels Hydrogen and Fuel Cell Hydrogen and Fuel Cell Find More Like This Return to Search Nanoporous Metal-Inorganic Materials for Storage and...

  19. The Materials Preparation Center - Making Rare Earth Metals - Part 3

    ScienceCinema (OSTI)

    Riedemann, Trevor

    2013-03-01T23:59:59.000Z

    Trevor Riedeman, manager of the MPC Rare Earth Materials Section, gives a presentation on the importance of rare earth metals and how they are made at Ames Laboratory. Part 3 of 4.

  20. The Materials Preparation Center - Making Rare Earth Metals - Part 1

    ScienceCinema (OSTI)

    Riedemann, Trevor

    2013-03-01T23:59:59.000Z

    Trevor Riedeman, manager of the MPC Rare Earth Materials Section, gives a presentation on the importance of rare earth metals and how they are made at Ames Laboratory. Part 1 of 4.

  1. The Materials Preparation Center - Making Rare Earth Metals - Part 4

    ScienceCinema (OSTI)

    Riedemann, Trevor

    2013-03-01T23:59:59.000Z

    Trevor Riedeman, manager of the MPC Rare Earth Materials Section, gives a presentation on the importance of rare earth metals and how they are made at Ames Laboratory. Part 4 of 4.

  2. Stabilized Lithium Metal Powder, Enabling Material and Revolutionary...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    -- Washington D.C. es011yakovleva2010o.pdf More Documents & Publications Stabilized Lithium Metal Powder, Enabling Material and Revolutionary Technology for High Energy Li-ion...

  3. The Materials Preparation Center - Making Rare Earth Metals - Part 3

    SciTech Connect (OSTI)

    Riedemann, Trevor

    2011-01-01T23:59:59.000Z

    Trevor Riedeman, manager of the MPC Rare Earth Materials Section, gives a presentation on the importance of rare earth metals and how they are made at Ames Laboratory. Part 3 of 4.

  4. The Materials Preparation Center - Making Rare Earth Metals - Part 1

    SciTech Connect (OSTI)

    Riedemann, Trevor

    2011-01-01T23:59:59.000Z

    Trevor Riedeman, manager of the MPC Rare Earth Materials Section, gives a presentation on the importance of rare earth metals and how they are made at Ames Laboratory. Part 1 of 4.

  5. The Materials Preparation Center - Making Rare Earth Metals - Part 4

    SciTech Connect (OSTI)

    Riedemann, Trevor

    2011-01-01T23:59:59.000Z

    Trevor Riedeman, manager of the MPC Rare Earth Materials Section, gives a presentation on the importance of rare earth metals and how they are made at Ames Laboratory. Part 4 of 4.

  6. The Materials Preparation Center - Making Rare Earth Metals - Part 2

    SciTech Connect (OSTI)

    Riedemann, Trevor

    2011-01-01T23:59:59.000Z

    Trevor Riedeman, manager of the MPC Rare Earth Materials Section, gives a presentation on the importance of rare earth metals and how they are made at Ames Laboratory. Part 2 of 4.

  7. The Materials Preparation Center - Making Rare Earth Metals - Part 2

    ScienceCinema (OSTI)

    Riedemann, Trevor

    2013-03-01T23:59:59.000Z

    Trevor Riedeman, manager of the MPC Rare Earth Materials Section, gives a presentation on the importance of rare earth metals and how they are made at Ames Laboratory. Part 2 of 4.

  8. Graded core/shell semiconductor nanorods and nanorod barcodes

    DOE Patents [OSTI]

    Alivisatos, A. Paul; Scher, Erik C.; Manna, Liberato

    2013-03-26T23:59:59.000Z

    Graded core/shell semiconductor nanorods and shapped nanorods are disclosed comprising Group II-VI, Group III-V and Group IV semiconductors and methods of making the same. Also disclosed are nanorod barcodes using core/shell nanorods where the core is a semiconductor or metal material, and with or without a shell. Methods of labeling analytes using the nanorod barcodes are also disclosed.

  9. Graded core/shell semiconductor nanorods and nanorod barcodes

    DOE Patents [OSTI]

    Alivisatos, A. Paul (Oakland, CA); Scher, Erik C. (San Francisco, CA); Manna, Liberato (Lecce, IT)

    2010-12-14T23:59:59.000Z

    Graded core/shell semiconductor nanorods and shaped nanorods are disclosed comprising Group II-VI, Group III-V and Group IV semiconductors and methods of making the same. Also disclosed are nanorod barcodes using core/shell nanorods where the core is a semiconductor or metal material, and with or without a shell. Methods of labeling analytes using the nanorod barcodes are also disclosed.

  10. Apparatus and method for measuring minority carrier lifetimes in semiconductor materials

    DOE Patents [OSTI]

    Ahrenkiel, Richard K. (Lakewood, CO); Johnston, Steven W. (Golden, CO)

    2001-01-01T23:59:59.000Z

    An apparatus for determining the minority carrier lifetime of a semiconductor sample includes a positioner for moving the sample relative to a coil. The coil is connected to a bridge circuit such that the impedance of one arm of the bridge circuit is varied as sample is positioned relative to the coil. The sample is positioned relative to the coil such that any change in the photoconductance of the sample created by illumination of the sample creates a linearly related change in the input impedance of the bridge circuit. In addition, the apparatus is calibrated to work at a fixed frequency so that the apparatus maintains a consistently high sensitivity and high linearity for samples of different sizes, shapes, and material properties. When a light source illuminates the sample, the impedance of the bridge circuit is altered as excess carriers are generated in the sample, thereby producing a measurable signal indicative of the minority carrier lifetimes or recombination rates of the sample.

  11. Features of an intermetallic n-ZrNiSn semiconductor heavily doped with atoms of rare-earth metals

    SciTech Connect (OSTI)

    Romaka, V. A., E-mail: vromaka@polynet.lviv.ua [National Academy of Sciences of Ukraine, Ya. Pidstryhach Institute for Applied Problems of Mechanics and Mathematics (Ukraine); Fruchart, D.; Hlil, E. K. [CNRS, Institute Neel (France); Gladyshevskii, R. E. [Ivan Franko Lviv National University (Ukraine); Gignoux, D. [CNRS, Institute Neel (France); Romaka, V. V.; Kuzhel, B. S. [Ivan Franko Lviv National University (Ukraine); Krayjvskii, R. V. [Lvivska Politechnika National University (Ukraine)

    2010-03-15T23:59:59.000Z

    The crystal structure, density of electron states, electron transport, and magnetic characteristics of an intermetallic n-ZrNiSn semiconductor heavily doped with atoms of rare-earth metals (R) have been studied in the ranges of temperatures 1.5-400 K, concentrations of rare-earth metal 9.5 x 10{sup 19}-9.5 x 10{sup 21} cm{sup -3}, and magnetic fields H {<=} 15 T. The regions of existence of Zr{sub 1-x}R{sub x}NiSn solid solutions are determined, criteria for solubility of atoms of rare-earth metals in ZrNiSn and for the insulator-metal transition are formulated, and the nature of 'a priori doping' of ZrNiSn is determined as a result of redistribution of Zr and Ni atoms at the crystallographic sites of Zr. Correlation between the concentration of the R impurity, the amplitude of modulation of the bands of continuous energies, and the degree of occupation of potential wells of small-scale fluctuations with charge carriers is established. The results are discussed in the context of the Shklovskii-Efros model of a heavily doped and compensated semiconductor.

  12. Enhanced Semiconductor Nanocrystal Conductance via Solution Grown Contacts

    E-Print Network [OSTI]

    Sheldon, Matthew T.

    2010-01-01T23:59:59.000Z

    G. ; Avouris, P. , Metal-semiconductor nanocontacts: SiliconIndividual Colloidal Semiconductor Nanorods. Nano Lett 2008,Physical Chemistry of Semiconductor Nanocrystals. J. Phys.

  13. Dilute magnetic semiconductor and half-metal behaviour mediated by 3d transition-metal doped in black/blue phosphorene

    E-Print Network [OSTI]

    Yu, Weiyang; Niu, Chun-Yao; Li, Chong; Cho, Jun-Hyung; Jia, Yu

    2015-01-01T23:59:59.000Z

    Using first-principles calculations, we present a theoretical study of the structural, electronic and magnetic properties of 3d transition metal (TM) atoms interacting with phosphorus monovacancies in two-dimensional black/blue phosphorene. We pay special attention to the magnetic properties of these substitutional impurities and find that they can be fully understood by a simple model based on the Hund's rule. For TM-doped black phosphorene, the calculated band structures of substitutional Ti, Cr, Mn, Fe and Ni impurities show dilute magnetic semiconductor (DMS) properties while those of substitutional Sc, V and Co impurities show nonmagnetic property. For TM-doped blue phosphorene, the calculated band structures of substitutional V, Cr, Mn and Fe impurities show DMS properties, and those of substitutional Ti and Ni impurities show half-metal properties, while Sc and V impurities show nonmagnetic property. We identify three different regimes associated with the occupation of different phosphorus-metal hybrid...

  14. Composite Materials for Hazard Mitigation of Reactive Metal Hydrides.

    SciTech Connect (OSTI)

    Pratt, Joseph William; Cordaro, Joseph Gabriel; Sartor, George B.; Dedrick, Daniel E.; Reeder, Craig L.

    2012-02-01T23:59:59.000Z

    In an attempt to mitigate the hazards associated with storing large quantities of reactive metal hydrides, polymer composite materials were synthesized and tested under simulated usage and accident conditions. The composites were made by polymerizing vinyl monomers using free-radical polymerization chemistry, in the presence of the metal hydride. Composites with vinyl-containing siloxane oligomers were also polymerized with and without added styrene and divinyl benzene. Hydrogen capacity measurements revealed that addition of the polymer to the metal hydride reduced the inherent hydrogen storage capacity of the material. The composites were found to be initially effective at reducing the amount of heat released during oxidation. However, upon cycling the composites, the mitigating behavior was lost. While the polymer composites we investigated have mitigating potential and are physically robust, they undergo a chemical change upon cycling that makes them subsequently ineffective at mitigating heat release upon oxidation of the metal hydride. Acknowledgements The authors would like to thank the following people who participated in this project: Ned Stetson (U.S. Department of Energy) for sponsorship and support of the project. Ken Stewart (Sandia) for building the flow-through calorimeter and cycling test stations. Isidro Ruvalcaba, Jr. (Sandia) for qualitative experiments on the interaction of sodium alanate with water. Terry Johnson (Sandia) for sharing his expertise and knowledge of metal hydrides, and sodium alanate in particular. Marcina Moreno (Sandia) for programmatic assistance. John Khalil (United Technologies Research Corp) for insight into the hazards of reactive metal hydrides and real-world accident scenario experiments. Summary In an attempt to mitigate and/or manage hazards associated with storing bulk quantities of reactive metal hydrides, polymer composite materials (a mixture of a mitigating polymer and a metal hydride) were synthesized and tested under simulated usage and accident conditions. Mitigating the hazards associated with reactive metal hydrides during an accident while finding a way to keep the original capability of the active material intact during normal use has been the focus of this work. These composites were made by polymerizing vinyl monomers using free-radical polymerization chemistry, in the presence of the metal hydride, in this case a prepared sodium alanate (chosen as a representative reactive metal hydride). It was found that the polymerization of styrene and divinyl benzene could be initiated using AIBN in toluene at 70 degC. The resulting composite materials can be either hard or brittle solids depending on the cross-linking density. Thermal decomposition of these styrene-based composite materials is lower than neat polystyrene indicating that the chemical nature of the polymer is affected by the formation of the composite. The char-forming nature of cross-linked polystyrene is low and therefore, not an ideal polymer for hazard mitigation. To obtain composite materials containing a polymer with higher char-forming potential, siloxane-based monomers were investigated. Four vinyl-containing siloxane oligomers were polymerized with and without added styrene and divinyl benzene. Like the styrene materials, these composite materials exhibited thermal decomposition behavior significantly different than the neat polymers. Specifically, the thermal decomposition temperature was shifted approximately 100 degC lower than the neat polymer signifying a major chemical change to the polymer network. Thermal analysis of the cycled samples was performed on the siloxane-based composite materials. It was found that after 30 cycles the siloxane-containing polymer composite material has similar TGA/DSC-MS traces as the virgin composite material indicating that the polymer is physically intact upon cycling. Hydrogen capacity measurements revealed that addition of the polymer to the metal hydride in the form of a composite material reduced the inherent hydrogen storage capacity of the material. This

  15. Time-resolved THz studies of carrier dynamics in semiconductors, superconductors, and strongly-correlated electron materials

    E-Print Network [OSTI]

    Kaindl, Robert A

    2011-01-01T23:59:59.000Z

    correlation effects in semiconductors, Nature 411, 549-557,in optically excited semiconductors, Phys. Rev. B 54,and Terahertz Gain in Semiconductors Excited to Resonance,

  16. Disorder induced semiconductor to metal transition and modifications of grain boundaries in nanocrystalline zinc oxide thin film

    SciTech Connect (OSTI)

    Singh, Fouran; Kumar, Vinod [Materials Science Group, Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India); Chaudhary, Babloo [Centre of Excellence in Material Sciences and Nanomaterials, Z. H. College of Engineering and Technology, Aligarh Muslim University, Aligarh, U.P. 202001 (India); Singh, R. G. [Department of Electronic Science, Maharaja Agrasen College, University of Delhi, New Delhi 110096 (India); Kumar, Sanjeev [Materials Science Group, Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India); Department of Electronic Science, University of Delhi South Campus, New Delhi 110023 (India); Kapoor, A. [Department of Electronic Science, University of Delhi South Campus, New Delhi 110023 (India)

    2012-10-01T23:59:59.000Z

    This paper report on the disorder induced semiconductor to metal transition (SMT) and modifications of grain boundaries in nanocrystalline zinc oxide thin film. Disorder is induced using energetic ion irradiation. It eliminates the possibility of impurities induced transition. However, it is revealed that some critical concentration of defects is needed for inducing such kind of SMT at certain critical temperature. Above room temperature, the current-voltage characteristics in reverse bias attributes some interesting phenomenon, such as electric field induced charge transfer, charge trapping, and diffusion of defects. The transition is explained by the defects induced disorder and strain in ZnO crystallites created by high density of electronic excitations.

  17. Metal-ion spin-on glasses: Novel materials for active waveguides

    SciTech Connect (OSTI)

    Ashby, C.I.H.; Sullivan, C.T.; Vawter, G.A.; Hohimer, J.P.; Hadley, G.R.; Neal, D.R.

    1993-12-31T23:59:59.000Z

    Monolithic integration of a rare-earth-ion-based active waveguide on the same wafer as its diode pump laser would permit compact packaging of the technology demonstrated in fiber lasers and amplifiers. This new monolithic technology would offer the potential for developing compact infrared and visible (up-conversion) lasers, amplifiers, and other photonic integrated circuit components. One approach that we are investigating for such monolithic integration uses a high concentration of one or more rare-earth ions incorporated into polysiloxane spin-on glasses that are solvent-cast onto III-V semiconductor wafers. This ``fiber on a chip`` technology substitute a relatively high-ion-concentration, short-length metal-ion spin-on glass (MISOG) waveguide for the low-ion-concentration, long-length fiber. Progress to data on developing MISOG waveguide materials and technology is discussed.

  18. Ballistic performance comparison of monolayer transition metal dichalcogenide MX{sub 2} (M = Mo, W; X = S, Se, Te) metal-oxide-semiconductor field effect transistors

    SciTech Connect (OSTI)

    Chang, Jiwon; Register, Leonard F.; Banerjee, Sanjay K. [Microelectronics Research Center, The University of Texas at Austin, Austin, Texas 78758 (United States)

    2014-02-28T23:59:59.000Z

    We study the transport properties of monolayer MX{sub 2} (M?=?Mo, W; X?=?S, Se, Te) n- and p-channel metal-oxide-semiconductor field effect transistors (MOSFETs) using full-band ballistic non-equilibrium Green's function simulations with an atomistic tight-binding Hamiltonian with hopping potentials obtained from density functional theory. We discuss the subthreshold slope, drain-induced barrier lowering (DIBL), as well as gate-induced drain leakage (GIDL) for different monolayer MX{sub 2} MOSFETs. We also report the possibility of negative differential resistance behavior in the output characteristics of nanoscale monolayer MX{sub 2} MOSFETs.

  19. Metal-oxide-based energetic materials and synthesis thereof

    DOE Patents [OSTI]

    Tillotson, Thomas M. (Tracy, CA), Simpson; Randall L. (Livermore, CA); Hrubesh, Lawrence W. (Pleasanton, CA)

    2006-01-17T23:59:59.000Z

    A method of preparing energetic metal-oxide-based energetic materials using sol-gel chemistry has been invented. The wet chemical sol-gel processing provides an improvement in both safety and performance. Essentially, a metal-oxide oxidizer skeletal structure is prepared from hydrolyzable metals (metal salts or metal alkoxides) with fuel added to the sol prior to gelation or synthesized within the porosity metal-oxide gel matrix. With metal salt precursors a proton scavenger is used to destabilize the sol and induce gelation. With metal alkoxide precursors standard well-known sol-gel hydrolysis and condensation reactions are used. Drying is done by standard sol-gel practices, either by a slow evaporation of the liquid residing within the pores to produce a high density solid nanocomposite, or by supercritical extraction to produce a lower density, high porous nanocomposite. Other ingredients may be added to this basic nanostructure to change physical and chemical properties, which include organic constituents for binders or gas generators during reactions, burn rate modifiers, or spectral emitters.

  20. Inorganic Chemistry Solutions to Semiconductor Nanocrystal Problems

    SciTech Connect (OSTI)

    Alvarado, Samuel R. [Ames Laboratory; Guo, Yijun [Ames Laboratory; Ruberu, T. Purnima A. [Ames Laboratory; Tavasoli, Elham [Ames Laboratory; Vela, Javier [Ames Laboratory

    2014-03-15T23:59:59.000Z

    The optoelectronic and chemical properties of semiconductor nanocrystals heavily depend on their composition, size, shape and internal structure, surface functionality, etc. Available strategies to alter these properties through traditional colloidal syntheses and ligand exchange methods place a premium on specific reaction conditions and surfactant combinations. In this invited review, we apply a molecular-level understanding of chemical precursor reactivity to reliably control the morphology, composition and intimate architecture (core/shell vs. alloyed) of semiconductor nanocrystals. We also describe our work aimed at achieving highly selective, low-temperature photochemical methods for the synthesis of semiconductor–metal and semiconductor–metal oxide photocatalytic nanocomposites. In addition, we describe our work on surface modification of semiconductor nanocrystal quantum dots using new approaches and methods that bypass ligand exchange, retaining the nanocrystal's native ligands and original optical properties, as well as on spectroscopic methods of characterization useful in determining surface ligand organization and chemistry. Using recent examples from our group and collaborators, we demonstrate how these efforts have lead to faster, wider and more systematic application of semiconductor nanocrystal-based materials to biological imaging and tracking, and to photocatalysis of unconventional substrates. We believe techniques and methods borrowed from inorganic chemistry (including coordination, organometallic and solid state chemistry) have much to offer in reaching a better understanding of the synthesis, functionalization and real-life application of such exciting materials as semiconductor nanocrystals (quantum dots, rods, tetrapods, etc.).

  1. High capacity nickel battery material doped with alkali metal cations

    DOE Patents [OSTI]

    Jackovitz, John F. (Monroeville, PA); Pantier, Earl A. (Penn Hills, PA)

    1982-05-18T23:59:59.000Z

    A high capacity battery material is made, consisting essentially of hydrated Ni(II) hydroxide, and about 5 wt. % to about 40 wt. % of Ni(IV) hydrated oxide interlayer doped with alkali metal cations selected from potassium, sodium and lithium cations.

  2. Disordered electronic and magnetic systems - transition metal (Mn) and rare earth (Gd) doped amorphous group IV semiconductors (C, Si, Ge)

    E-Print Network [OSTI]

    Zeng, Li

    2007-01-01T23:59:59.000Z

    magnetic semiconductors: the europium chalcogenides. Phys.Classic examples are europium chalcogenides [3], Gd 3?x ? xmagnetic semiconductor europium chalcogenides, where the

  3. Semiconductors and sustainability : energy and materials use in integrated circuit manufacturing

    E-Print Network [OSTI]

    Branham, Matthew S

    2008-01-01T23:59:59.000Z

    Semiconductors have propelled an incredible revolution in the way we generate, access, store, and communicate information; the effects of this revolution have transformed culture, society, and the economy. At the same time, ...

  4. Development of materials resistant to metal dusting degradation.

    SciTech Connect (OSTI)

    Natesan, K.; Zeng, Z.

    2006-04-24T23:59:59.000Z

    Metal dusting corrosion has been a serious problem in the petroleum and petrochemical industries, such as reforming and syngas production systems. This form of deterioration has led to worldwide material loss for 50 years. For the past three years, we have studied the mechanism of metal dusting for Fe- and Ni-base alloys. In this report, we present a correlation between the weight loss and depth of pits that form in Ni-base alloys. Nickel-base alloys were also tested at 1 and 14.8 atm (210 psi), in a high carbon activity environment. Higher system pressure was found to accelerate corrosion in most Ni-base alloys. To reduce testing time, a pre-pitting method was developed. Mechanical scratches on the alloy surface led to fast metal dusting corrosion. We have also developed preliminary data on the performance of weldments of several Ni-base alloys in a metal dusting environment. Finally, Alloy 800 tubes and plates used in a reformer plant were examined by scanning electron microscopy, energy dispersive X-ray, and Raman spectroscopy. The oxide scale on the surface of the Alloy 800 primarily consists of Fe{sub 1+x}Cr{sub 2-X}O{sub 4} spinel phase with high Fe content. Carbon can diffuse through this oxide scale. It was discovered that the growth of metal dusting pits could be stopped by means of a slightly oxidized alloy surface. This leads to a new way to solve metal dusting problem.

  5. Self-heating simulation of GaN-based metal-oxide-semiconductor high-electron-mobility transistors including hot electron

    E-Print Network [OSTI]

    Ye, Peide "Peter"

    Self-heating simulation of GaN-based metal-oxide-semiconductor high-electron-mobility transistors the results of self-heating simulations of the GaN-based MOS-HEMTs, including hot electron and quantum effects of the gate and source/drain extension lengths on both the output performance and self-heating is discussed

  6. Strained Ge channel p-type metal-oxide-semiconductor field-effect transistors grown on Siâ?â??xGex/Si virtual substrates

    E-Print Network [OSTI]

    Lee, Minjoo L.

    We have fabricated strained Ge channel p-type metal-oxide-semiconductor field-effect transistors (p-MOSFETs) on Siâ??.â??Geâ??.â?? virtual substrates. The poor interface between silicon dioxide (SiOâ??) and the Ge channel ...

  7. Electron Transport Behavior on Gate Length Scaling in Sub-50 nm GaAs Metal Semiconductor Field Effect Transistors

    SciTech Connect (OSTI)

    Han, Jaeheon [Department of Electronic Engineering, Kangnam University, 111 Gugal-dong, Giheung-gu, Yongin-city, Gyeonggi-do, Korea 446-702 (Korea, Republic of)

    2011-12-23T23:59:59.000Z

    Short channel GaAs Metal Semiconductor Field Effect Transistors (MESFETs) have been fabricated with gate length to 20 nm, in order to examine the characteristics of sub-50 nm MESFET scaling. Here the rise in the measured transconductance is mainly attributed to electron velocity overshoot. For gate lengths below 40 nm, however, the transconductance drops suddenly. The behavior of velocity overshoot and its degradation is investigated and simulated by using a transport model based on the retarded Langevin equation (RLE). This indicates the existence of a minimum acceleration length needed for the carriers to reach the overshoot velocity. The argument shows that the source resistance must be included as an internal element, or appropriate boundary condition, of relative importance in any model where the gate length is comparable to the inelastic mean free path of the carriers.

  8. Experimental study on vertical scaling of InAs-on-insulator metal-oxide-semiconductor field-effect transistors

    SciTech Connect (OSTI)

    Kim, SangHyeon, E-mail: dadembyora@mosfet.t.u-tokyo.ac.jp, E-mail: sh-kim@kist.re.kr; Yokoyama, Masafumi; Nakane, Ryosho; Takenaka, Mitsuru; Takagi, Shinichi [Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Ichikawa, Osamu; Osada, Takenori; Hata, Masahiko [Sumitomo Chemical Co., Ltd., 6 Kitahara, Tsukuba, Ibaraki 300-3294 (Japan)

    2014-06-30T23:59:59.000Z

    We have investigated effects of the vertical scaling on electrical properties in extremely thin-body InAs-on-insulator (-OI) metal-oxide-semiconductor field-effect transistors (MOSFETs). It is found that the body thickness (T{sub body}) scaling provides better short channel effect (SCE) control, whereas the T{sub body} scaling also causes the reduction of the mobility limited by channel thickness fluctuation (?T{sub body}) scattering (?{sub fluctuation}). Also, in order to achieve better SCEs control, the thickness of InAs channel layer (T{sub channel}) scaling is more favorable than the thickness of MOS interface buffer layer (T{sub buffer}) scaling from a viewpoint of a balance between SCEs control and ?{sub fluctuation} reduction. These results indicate necessity of quantum well channel structure in InAs-OI MOSFETs and these should be considered in future transistor design.

  9. Semiconductor-metal phase transition of vanadium dioxide nanostructures on silicon substrate: Applications for thermal control of spacecraft

    SciTech Connect (OSTI)

    Leahu, G. L., E-mail: roberto.livoti@uniroma1.it; Li Voti, R., E-mail: roberto.livoti@uniroma1.it; Larciprete, M. C., E-mail: roberto.livoti@uniroma1.it; Belardini, A., E-mail: roberto.livoti@uniroma1.it; Mura, F., E-mail: roberto.livoti@uniroma1.it; Sibilia, C.; Bertolotti, M. [Dipartimento di Scienze di Base ed Applicate per l'Ingegneria, Sapienza Università di Roma, Via A. Scarpa 16 00161 Roma (Italy); Fratoddi, I. [Dipartimento di Chimica, Sapienza Università di Roma, Piazzale A. Moro, Roma (Italy)

    2014-06-19T23:59:59.000Z

    We present a detailed infrared study of the semiconductor-to-metal transition (SMT) in a vanadium dioxide (VO2) film deposited on silicon wafer. The VO2 phase transition is studied in the mid-infrared (MIR) region by analyzing the transmittance and the reflectance measurements, and the calculated emissivity. The temperature behaviour of the emissivity during the SMT put into evidence the phenomenon of the anomalous absorption in VO2 which has been explained by applying the Maxwell Garnett effective medium approximation theory, together with a strong hysteresis phenomenon, both useful to design tunable thermal devices to be applied for the thermal control of spacecraft. We have also applied the photothermal radiometry in order to study the changes in the modulated emissivity induced by laser. Experimental results show how the use of these techniques represent a good tool for a quantitative measurement of the optothermal properties of vanadium dioxide based structures.

  10. Photo-response of a P3HT:PCBM blend in metal-insulator-semiconductor capacitors

    SciTech Connect (OSTI)

    Devynck, M.; Rostirolla, B.; Watson, C. P.; Taylor, D. M., E-mail: d.m.taylor@bangor.ac.uk [School of Electronic Engineering, Bangor University, Dean Street, Bangor, Gwynedd LL57 1UT (United Kingdom)

    2014-11-03T23:59:59.000Z

    Metal-insulator-semiconductor capacitors are investigated, in which the insulator is cross-linked polyvinylphenol and the active layer a blend of poly(3-hexylthiophene), P3HT, and the electron acceptor [6,6]-phenyl-C{sub 61}-butyric acid methyl ester (PCBM). Admittance spectra and capacitance-voltage measurements obtained in the dark both display similar behaviour to those previously observed in P3HT-only devices. However, the photo-capacitance response is significantly enhanced in the P3HT:PCBM case, where exciton dissociation leads to electron transfer into the PCBM component. The results are consistent with a network of PCBM aggregates that is continuous through the film but with no lateral interconnection between the aggregates at or near the blend/insulator interface.

  11. Nitride semiconductor Surface and interface characterization and device design

    E-Print Network [OSTI]

    Zhang, Hongtao

    2006-01-01T23:59:59.000Z

    Lett. 80 , D. Schroder, Semiconductor Material and Devicein III-V Nitride Semiconductors: Applications and Devices ,SAN DIEGO Nitride Semiconductor Surface and Interface

  12. ECE 609 Semiconductor Devices Department of Electrical and Computer Engineering

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    ECE 609 ­ Semiconductor Devices Department of Electrical and Computer Engineering University of semiconductor electronic devices in terms of material properties, interface and junction characteristics). ________________________________________________________________________ Preliminary Course Outline 1. Overview of Semiconductor Physics 1.1 Semiconductor Materials

  13. Electrochemical lithiation and delithiation for control of magnetic properties of nanoscale transition metal oxides

    E-Print Network [OSTI]

    Sivakumar, Vikram

    2008-01-01T23:59:59.000Z

    Transition metal oxides comprise a fascinating class of materials displaying a variety of magnetic and electronic properties, ranging from half-metallic ferromagnets like CrO2, ferrimagnetic semiconductors like Fey's, and ...

  14. Influence of metals & humic materials on degradation of CCI4 by Pseudomonas

    SciTech Connect (OSTI)

    Ronald L. Crawford, Ph.D.

    2000-10-14T23:59:59.000Z

    (oak- 259) To test factor-KC with metals, radionuclides, and humic materials for CCI4 bioremediation

  15. Survey of Materials for Nanoskiving and Influence of the Cutting Process on the

    E-Print Network [OSTI]

    Church, George M.

    Survey of Materials for Nanoskiving and Influence of the Cutting Process on the Nanostructures materials (metals, ceramics, semiconductors, and conjugated polymers), deposition techniques (evaporation. The materials tested were: aluminum, titanium, nickel, copper, palladium, silver, platinum, gold, lead, bismuth

  16. 2012 DEFECTS IN SEMICONDUCTORS GORDON RESEARCH CONFERENCE, AUGUST 12-17, 2012

    SciTech Connect (OSTI)

    GLASER, EVAN

    2012-08-17T23:59:59.000Z

    The meeting shall strive to develop and further the fundamental understanding of defects and their roles in the structural, electronic, optical, and magnetic properties of bulk, thin film, and nanoscale semiconductors and device structures. Point and extended defects will be addressed in a broad range of electronic materials of particular current interest, including wide bandgap semiconductors, metal-oxides, carbon-based semiconductors (e.g., diamond, graphene, etc.), organic semiconductors, photovoltaic/solar cell materials, and others of similar interest. This interest includes novel defect detection/imaging techniques and advanced defect computational methods.

  17. Mass and charge overlaps in beamline implantation into compound semiconductor materials

    SciTech Connect (OSTI)

    Current, M. I.; Eddy, R.; Hudak, C.; Serfass, J.; Mount, G. [Current Scientific, 1729 Comstock Way, San Jose, CA 95124 (United States); Core Systems, 1050 Kifer Rd., Sunnyvale, CA 94086 (United States); Evans Analytical Group, 810 Kifer Rd., Sunnyvale, CA 95051 (United States)

    2012-11-06T23:59:59.000Z

    Mass overlaps occurring as a result of extraction of ions from an arc discharge and gas collisions, producing molecular break up and charge exchange in the accelerator beamline, are examined for ion implantation into compound semiconductors. The effects of the choice of plasma gas elements for Be{sup +} implants are examined as an example.

  18. Semiconductor nanowire thermoelectric materials and devices, and processes for producing same

    DOE Patents [OSTI]

    Lagally, Max G; Evans, Paul G; Ritz, Clark S

    2013-09-17T23:59:59.000Z

    The present invention provides nanowires and nanoribbons that are well suited for use in thermoelectric applications. The nanowires and nanoribbons are characterized by a periodic compositional longitudinal modulation. The nanowires are constructed using lithographic techniques from thin semiconductor membranes, or "nanomembranes."

  19. Semiconductor nanowire thermoelectric materials and devices, and processes for producing same

    DOE Patents [OSTI]

    Lagally, Max G. (Madison, WI); Evans, Paul G. (Madison, WI); Ritz, Clark S. (Middleton, WI)

    2011-02-15T23:59:59.000Z

    The present invention provides nanowires and nanoribbons that are well suited for use in thermoelectric applications. The nanowires and nanoribbons are characterized by a periodic longitudinal modulation, which may be a compositional modulation or a strain-induced modulation. The nanowires are constructed using lithographic techniques from thin semiconductor membranes, or "nanomembranes."

  20. Method and apparatus for electron-only radiation detectors from semiconductor materials

    DOE Patents [OSTI]

    Lund, James C. (429 Warwick Ave., San Leandro, CA 94577)

    2000-01-01T23:59:59.000Z

    A system for obtaining improved resolution in room temperature semiconductor radiation detectors such as CdZnTe and Hgl.sub.2, which exhibit significant hole-trapping. A electrical reference plane is established about the perimeter of a semiconductor crystal and disposed intermediately between two oppositely biased end electrodes. The intermediate reference plane comprises a narrow strip of wire in electrical contact with the surface of the crystal, biased at a potential between the end electrode potentials and serving as an auxiliary electrical reference for a chosen electrode--typically the collector electrode for the more mobile charge carrier. This arrangement eliminates the interfering effects of the less mobile carriers as these are gathered by their electrode collector.

  1. Semiconductor bridge (SCB) detonator

    DOE Patents [OSTI]

    Bickes, R.W. Jr.; Grubelich, M.C.

    1999-01-19T23:59:59.000Z

    The present invention is a low-energy detonator for high-density secondary-explosive materials initiated by a semiconductor bridge (SCB) igniter that comprises a pair of electrically conductive lands connected by a semiconductor bridge. The semiconductor bridge is in operational or direct contact with the explosive material, whereby current flowing through the semiconductor bridge causes initiation of the explosive material. Header wires connected to the electrically-conductive lands and electrical feed-throughs of the header posts of explosive devices, are substantially coaxial to the direction of current flow through the SCB, i.e., substantially coaxial to the SCB length. 3 figs.

  2. Semiconductor bridge (SCB) detonator

    DOE Patents [OSTI]

    Bickes, Jr., Robert W. (Albuquerque, NM); Grubelich, Mark C. (Albuquerque, NM)

    1999-01-01T23:59:59.000Z

    The present invention is a low-energy detonator for high-density secondary-explosive materials initiated by a semiconductor bridge igniter that comprises a pair of electrically conductive lands connected by a semiconductor bridge. The semiconductor bridge is in operational or direct contact with the explosive material, whereby current flowing through the semiconductor bridge causes initiation of the explosive material. Header wires connected to the electrically-conductive lands and electrical feed-throughs of the header posts of explosive devices, are substantially coaxial to the direction of current flow through the SCB, i.e., substantially coaxial to the SCB length.

  3. Cyclic catalytic upgrading of chemical species using metal oxide materials

    DOE Patents [OSTI]

    White, James H; Schutte, Erick J; Rolfe, Sara L

    2013-05-07T23:59:59.000Z

    Processes are disclosure which comprise alternately contacting an oxygen-carrying catalyst with a reducing substance, or a lower partial pressure of an oxidizing gas, and then with the oxidizing gas or a higher partial pressure of the oxidizing gas, whereby the catalyst is alternately reduced and then regenerated to an oxygenated state. In certain embodiments, the oxygen-carrying catalyst comprises at least one metal oxide-containing material containing a composition having the following formulas: (a) Ce.sub.xB.sub.yB'.sub.zB''O.sub..delta., wherein B=Ba, Sr, Ca, or Zr; B'=Mn, Co, and/or Fe; B''=Cu; 0.01material itself or as a support for said unary or binary metal oxides.

  4. Ceramic superconductor/metal composite materials employing the superconducting proximity effect

    DOE Patents [OSTI]

    Holcomb, Matthew J. (Manhattan Beach, CA)

    2002-01-01T23:59:59.000Z

    Superconducting composite materials having particles of superconducting material disposed in a metal matrix material with a high electron-boson coupling coefficient (.lambda.). The superconducting particles can comprise any type of superconductor including Laves phase materials, Chevrel phase materials, A15 compounds, and perovskite cuprate ceramics. The particles preferably have dimensions of about 10-500 nanometers. The particles preferably have dimensions larger than the superconducting coherence length of the superconducting material. The metal matrix material has a .lambda. greater than 0.2, preferably the .lambda. is much higher than 0.2. The metal matrix material is a good proximity superconductor due to its high .lambda.. When cooled, the superconductor particles cause the metal matrix material to become superconducting due to the proximity effect. In cases where the particles and the metal matrix material are chemically incompatible (i.e., reactive in a way that destroys superconductivity), the particles are provided with a thin protective metal coating. The coating is chemically compatible with the particles and metal matrix material. High Temperature Superconducting (HTS) cuprate ceramic particles are reactive and therefore require a coating of a noble metal resistant to oxidation (e.g., silver, gold). The proximity effect extends through the metal coating. With certain superconductors, non-noble metals can be used for the coating.

  5. Direct observation of both contact and remote oxygen scavenging of GeO{sub 2} in a metal-oxide-semiconductor stack

    SciTech Connect (OSTI)

    Fadida, S., E-mail: sivanfa@tx.technion.ac.il; Shekhter, P.; Eizenberg, M. [Department of Materials Science and Engineering, Technion-Israel Institute of Technology, Haifa (Israel); Cvetko, D. [Laboratorio TASC/IOM-CNR, Area di ricerca, Trieste (Italy); Department of Physics, Faculty of Mathematics and Physics, University of Ljubljana, Ljubljana (Slovenia); Floreano, L.; Verdini, A. [Laboratorio TASC/IOM-CNR, Area di ricerca, Trieste (Italy); Nyns, L.; Van Elshocht, S. [Imec, Kapeldreef 75, B-3001 Leuven (Belgium); Kymissis, I. [Department of Electrical Engineering, Columbia University, New York, New York 10027 (United States)

    2014-10-28T23:59:59.000Z

    In the path to incorporating Ge based metal-oxide-semiconductor into modern nano-electronics, one of the main issues is the oxide-semiconductor interface quality. Here, the reactivity of Ti on Ge stacks and the scavenging effect of Ti were studied using synchrotron X-ray photoelectron spectroscopy measurements, with an in-situ metal deposition and high resolution transmission electron microscopy imaging. Oxygen removal from the Ge surface was observed both in direct contact as well as remotely through an Al{sub 2}O{sub 3} layer. The scavenging effect was studied in situ at room temperature and after annealing. We find that the reactivity of Ti can be utilized for improved scaling of Ge based devices.

  6. Industrial recovered-materials-utilization targets for the metals and metal-products industry

    SciTech Connect (OSTI)

    None

    1980-03-01T23:59:59.000Z

    The National Energy Conservation Policy Act of 1978 directs DOE to set targets for increased utilization of energy-saving recovered materials for certain industries. These targets are to be established at levels representing the maximum feasible increase in utilization of recovered materials that can be achieved progressively by January 1, 1987 and is consistent with technical and economic factors. A benefit to be derived from the increased use of recoverable materials is in energy savings, as state in the Act. Therefore, emhasis on different industries in the metals sector has been related to their energy consumption. The ferrous industry (iron and steel, ferrour foundries and ferralloys), as defined here, accounts for approximately 3%, and all others for the remaining 3%. Energy consumed in the lead and zinc segments is less than 1% each. Emphasis is placed on the ferrous scrap users, followed by the aluminum and copper industries. A bibliography with 209 citations is included.

  7. Radio frequency coupling apparatus and method for measuring minority carrier lifetimes in semiconductor materials

    DOE Patents [OSTI]

    Johnston, Steven W. (Golden, CO); Ahrenkiel, Richard K. (Lakewood, CO)

    2002-01-01T23:59:59.000Z

    An apparatus for measuring the minority carrier lifetime of a semiconductor sample using radio-frequency coupling. The measuring apparatus includes an antenna that is positioned a coupling distance from a semiconductor sample which is exposed to light pulses from a laser during sampling operations. A signal generator is included to generate high frequency, such as 900 MHz or higher, sinusoidal waveform signals that are split into a reference signal and a sample signal. The sample signal is transmitted into a sample branch circuit where it passes through a tuning capacitor and a coaxial cable prior to reaching the antenna. The antenna is radio-frequency coupled with the adjacent sample and transmits the sample signal, or electromagnetic radiation corresponding to the sample signal, to the sample and receives reflected power or a sample-coupled-photoconductivity signal back. To lower impedance and speed system response, the impedance is controlled by limiting impedance in the coaxial cable and the antenna reactance. In one embodiment, the antenna is a waveguide/aperture hybrid antenna having a central transmission line and an adjacent ground flange. The sample-coupled-photoconductivity signal is then transmitted to a mixer which also receives the reference signal. To enhance the sensitivity of the measuring apparatus, the mixer is operated to phase match the reference signal and the sample-coupled-photoconductivity signal.

  8. Optical properties of two-dimensional transition metal dichalcogenides

    E-Print Network [OSTI]

    Lin, Yuxuan, S.M. Massachusetts Institute of Technology

    2014-01-01T23:59:59.000Z

    The re-discovery of the atomically thin transition metal dichalcogenides (TMDs), which are mostly semiconductors with a wide range of band gaps, has diversified the family of two-dimensional materials and boosted the ...

  9. Method of doping a semiconductor

    DOE Patents [OSTI]

    Yang, Chiang Y. (Miller Place, NY); Rapp, Robert A. (Columbus, OH)

    1983-01-01T23:59:59.000Z

    A method for doping semiconductor material. An interface is established between a solid electrolyte and a semiconductor to be doped. The electrolyte is chosen to be an ionic conductor of the selected impurity and the semiconductor material and electrolyte are jointly chosen so that any compound formed from the impurity and the semiconductor will have a free energy no lower than the electrolyte. A potential is then established across the interface so as to allow the impurity ions to diffuse into the semiconductor. In one embodiment the semiconductor and electrolyte may be heated so as to increase the diffusion coefficient.

  10. Method of bonding metals to ceramics and other materials

    DOE Patents [OSTI]

    Gruen, D.M.; Krauss, A.R.; DeWald, A.P.; Chienping Ju; Rigsbee, J.M.

    1993-01-05T23:59:59.000Z

    A composite and method of forming same wherein the composite has a non-metallic portion and an alloy portion wherein the alloy comprises an alkali metal and a metal which is an electrical conductor such as Cu, Ag, Al, Sn or Au and forms an alloy with the alkali metal. A cable of superconductors and composite is also disclosed.

  11. Native point defects in yttria and relevance to its use as a high-dielectric-constant gate oxide material: First-principles study

    E-Print Network [OSTI]

    Ceder, Gerbrand

    a promising gate oxide material to replace silicon dioxide in metal-oxide- semiconductor devices. Using-earth-doped lasers. Recently, Y2O3 has re- ceived attention as a promising candidate for replacing sili- con dioxide SiO2 as a gate dielectric material in metal- oxide-semiconductor MOS transistors.1­10 The continual

  12. Pressure Resistance Welding of High Temperature Metallic Materials

    SciTech Connect (OSTI)

    N. Jerred; L. Zirker; I. Charit; J. Cole; M. Frary; D. Butt; M. Meyer; K. L. Murty

    2010-10-01T23:59:59.000Z

    Pressure Resistance Welding (PRW) is a solid state joining process used for various high temperature metallic materials (Oxide dispersion strengthened alloys of MA957, MA754; martensitic alloy HT-9, tungsten etc.) for advanced nuclear reactor applications. A new PRW machine has been installed at the Center for Advanced Energy Studies (CAES) in Idaho Falls for conducting joining research for nuclear applications. The key emphasis has been on understanding processing-microstructure-property relationships. Initial studies have shown that sound joints can be made between dissimilar materials such as MA957 alloy cladding tubes and HT-9 end plugs, and MA754 and HT-9 coupons. Limited burst testing of MA957/HT-9 joints carried out at various pressures up to 400oC has shown encouraging results in that the joint regions do not develop any cracking. Similar joint strength observations have also been made by performing simple bend tests. Detailed microstructural studies using SEM/EBSD tools and fatigue crack growth studies of MA754/HT-9 joints are ongoing.

  13. Optical properties of metallic (III, Mn)V ferromagnetic semiconductors in the infrared to visible range

    E-Print Network [OSTI]

    Hankiewicz, EM; Jungwirth, T.; Dietl, T.; Timm, C.; Sinova, Jairo.

    2004-01-01T23:59:59.000Z

    , Phys. Rev. B 65, 201303(R) (2002). 11 K. W. Edmonds, P. Bogus?awski, K. Y. Wang, R. P. Campion, S. N. Novikov, N. R. S. Farley, B. L. Gallagher, C. T. Foxon, M. Sawicki, T. Dietl, M. B. Nardelli, and J. Bernholc, Phys. Rev. Lett. 92, 037201 (2004... of Complex Materials (Springer Verlag, Berlin, 2002). 21 T. Jungwirth, J. K?nig, J. Sinova, J. Ku?era, and A. H. Mac- Donald, Phys. Rev. B 66, 012402 (2002). 22 T. Jungwirth, J. Sinova, K. Wang, K. W. Edmonds, R. Campion, B. Gallagher, C. Foxon, Q. Niu...

  14. Practical Issues for Atom Probe Tomography Analysis of III-Nitride Semiconductor Materials

    E-Print Network [OSTI]

    Tanga, Fengzai; Moodya, Michael P.; Martina, Tomas L.; Bagota, Paul A. J.; Kappersa, Menno J.; Oliver, Rachel A.

    2015-04-30T23:59:59.000Z

    study of Cu grains 385 (Kempshall, et al., 2001). In terms of binary III-nitrides, the metal–N bond length in the 386 wurtzite structure increases from AlN, to GaN and to InN (Ambacher, 1998), being 387 associated with corresponding bond energy of 2...

  15. Recipient luminophoric mediums having narrow spectrum luminescent materials and related semiconductor light emitting devices and methods

    DOE Patents [OSTI]

    LeToquin, Ronan P; Tong, Tao; Glass, Robert C

    2014-12-30T23:59:59.000Z

    Light emitting devices include a light emitting diode ("LED") and a recipient luminophoric medium that is configured to down-convert at least some of the light emitted by the LED. In some embodiments, the recipient luminophoric medium includes a first broad-spectrum luminescent material and a narrow-spectrum luminescent material. The broad-spectrum luminescent material may down-convert radiation emitted by the LED to radiation having a peak wavelength in the red color range. The narrow-spectrum luminescent material may also down-convert radiation emitted by the LED into the cyan, green or red color range.

  16. OPTI 240: Semiconductor Physics and Lasers Instructor: Mahmoud Fallahi

    E-Print Network [OSTI]

    Arizona, University of

    OPTI 240: Semiconductor Physics and Lasers Instructor: Mahmoud Fallahi fallahi@optics.arizona.edu Spring Semester Introduction to Semiconductor Optoelectronic Introduction to quantum mechanics: Energy exclusion principle Metal, Insulator, Semiconductor Conduction band, valance band, energy gap Electrons

  17. Multifunctional Metallic and Refractory Materials for Energy Efficient Handling of Molten Metals

    SciTech Connect (OSTI)

    Xingbo Liu; Ever Barbero; Bruce Kang; Bhaskaran Gopalakrishnan; James Headrick; Carl Irwin

    2009-02-06T23:59:59.000Z

    The goal of the project was to extend the lifetime of hardware submerged in molten metal by an order of magnitude and to improve energy efficiency of molten metal handling process. Assuming broad implementation of project results, energy savings in 2020 were projected to be 10 trillion BTU/year, with cost savings of approximately $100 million/year. The project team was comprised of materials research groups from West Virginia University and the Missouri University of Science and Technology formerly University of Missouri – Rolla, Oak Ridge National Laboratory, International Lead and Zinc Research Organization, Secat and Energy Industries of Ohio. Industry partners included six suppliers to the hot dip galvanizing industry, four end-user steel companies with hot-dip Galvanize and/or Galvalume lines, eight refractory suppliers, and seven refractory end-user companies. The results of the project included the development of: (1) New families of materials more resistant to degradation in hot-dip galvanizing bath conditions were developed; (2) Alloy 2020 weld overlay material and process were developed and applied to GI rolls; (3) New Alloys and dross-cleaning procedures were developed for Galvalume processes; (4) Two new refractory compositions, including new anti-wetting agents, were identified for use with liquid aluminum alloys; (5) A new thermal conductivity measurement technique was developed and validated at ORNL; (6) The Galvanizing Energy Profiler Decision Support System (GEPDSS)at WVU; Newly Developed CCW Laser Cladding Shows Better Resistance to Dross Buildup than 316L Stainless Steel; and (7) A novel method of measuring the corrosion behavior of bath hardware materials. Project in-line trials were conducted at Southwire Kentucky Rod and Cable Mill, Nucor-Crawfordsville, Nucor-Arkansas, Nucor-South Carolina, Wheeling Nisshin, California Steel, Energy Industries of Ohio, and Pennex Aluminum. Cost, energy, and environmental benefits resulting from the project are due to: i) a reduced number of process shutdowns to change hardware or lining material, ii) reduced need to produce new hardware or lining material, iii) improved product quality leads to reduced need to remake product or manufacturing of new product, iv) reduction in contamination of melt from degradation of refractory and metallic components, v) elimination of worn hardware will increase efficiency of process, vi) reduced refractory lining deterioration or formation of a less insulating phase, would result in decreased heat loss through the walls. Projected 2015 benefits for the U.S. aluminum industry, assuming 21% market penetration of improved refractory materials, are energy savings of approximately 0.2 trillion BTU/year, cost savings of $2.3 billion/year and carbon reductions of approximately 1.4 billion tons/year. The carbon reduction benefit of the project for the hot-dip galvanize and aluminum industries combined is projected to be approximately 2.2 billion tons/year in 2015. Pathways from research to commercialization were based on structure of the project’s industrial partnerships. These partnerships included suppliers, industrial associations, and end users. All parties were involved in conducting the project including planning and critiquing the trials. Supplier companies such as Pyrotech Metaullics, Stoody, and Duraloy have commercialized products and processes developed on the project.

  18. Direct Modeling of Material Deposit and Identification of Energy Transfer in Gas Metal Arc Welding

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Direct Modeling of Material Deposit and Identification of Energy Transfer in Gas Metal Arc Welding sources for finite element simulation of gas metal arc welding (GMAW). Design for the modeling of metal deposition results in a direct calculation of the formation of the weld bead, without any

  19. Study of gate oxide traps in HfO[subscript 2]/AlGaN/GaN metal-oxide-semiconductor high-electron-mobility transistors by use of ac transconductance method

    E-Print Network [OSTI]

    Sun, X.

    We introduce an ac-transconductance method to profile the gate oxide traps in a HfO[subscript 2] gated AlGaN/GaN Metal-Oxide-Semiconductor High-Electron-Mobility Transistors (MOS-HEMTs) that can exchange carriers with metal ...

  20. Self assembled multi-layer nanocomposite of graphene and metal oxide materials

    SciTech Connect (OSTI)

    Liu, Jun; Choi, Daiwon; Kou, Rong; Nie, Zimin; Wang, Donghai; Yang, Zhenguo

    2014-09-16T23:59:59.000Z

    Nanocomposite materials having at least two layers, each layer consisting of one metal oxide bonded to at least one graphene layer were developed. The nanocomposite materials will typically have many alternating layers of metal oxides and graphene layers, bonded in a sandwich type construction and will be incorporated into an electrochemical or energy storage device.

  1. Self assembled multi-layer nanocomposite of graphene and metal oxide materials

    DOE Patents [OSTI]

    Liu, Jun; Aksay, Ilhan A; Choi, Daiwon; Kou, Rong; Nie, Zimin; Wang, Donghai; Yang, Zhenguo

    2013-10-22T23:59:59.000Z

    Nanocomposite materials having at least two layers, each layer consisting of one metal oxide bonded to at least one graphene layer were developed. The nanocomposite materials will typically have many alternating layers of metal oxides and graphene layers, bonded in a sandwich type construction and will be incorporated into an electrochemical or energy storage device.

  2. Synthesis and Hydrogen Sorption Properties of Carborane Based Metal-Organic Framework Materials

    E-Print Network [OSTI]

    Synthesis and Hydrogen Sorption Properties of Carborane Based Metal-Organic Framework Materials@northwestern.edu Tailorable inorganic coordination polymers,1-7 in particular, metal-organic frameworks (MOFs)2-7 comprise an important emerging class of materials. They are noteworthy for their structural and chemical diversity, high

  3. Standard test methods for Rockwell hardness of metallic materials

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2008-01-01T23:59:59.000Z

    1.1 These test methods cover the determination of the Rockwell hardness and the Rockwell superficial hardness of metallic materials by the Rockwell indentation hardness principle. This standard provides the requirements for Rockwell hardness machines and the procedures for performing Rockwell hardness tests. 1.2 This standard includes additional requirements in annexes: Verification of Rockwell Hardness Testing Machines\tAnnex A1 Rockwell Hardness Standardizing Machines\tAnnex A2 Standardization of Rockwell Indenters\tAnnex A3 Standardization of Rockwell Hardness Test Blocks\tAnnex A4 Guidelines for Determining the Minimum Thickness of a Test Piece\tAnnex A5 Hardness Value Corrections When Testing on Convex Cylindrical Surfaces\tAnnex A6 1.3 This standard includes nonmandatory information in appendixes which relates to the Rockwell hardness test. List of ASTM Standards Giving Hardness Values Corresponding to Tensile Strength\tAppendix X1 Examples of Procedures for Determining Rockwell Hardness Uncertainty\tAppendi...

  4. Cyclic catalytic upgrading of chemical species using metal oxide materials

    DOE Patents [OSTI]

    White, James H. (Boulder, CO); Schutte, Erick J. (Thornton, CO); Rolfe, Sara L. (Loveland, CO)

    2010-11-02T23:59:59.000Z

    Processes are disclosure which comprise alternately contacting an oxygen-carrying catalyst with a reducing substance, or a lower partial pressure of an oxidizing gas, and then with the oxidizing gas or a higher partial pressure of the oxidizing gas, whereby the catalyst is alternately reduced and then regenerated to an oxygenated state. In certain embodiments, the oxygen-carrying catalyst comprises at least one metal oxide-containing material containing a composition having one of the following formulas: (a) Ce.sub.xB.sub.yB'.sub.zB''O.sub..delta., wherein B=Ba, Sr, Ca, or Zr; B'=Mn, Co, or Fe; B''=Cu; 0.01

  5. Alkali metal recovery from carbonaceous material conversion process

    DOE Patents [OSTI]

    Sharp, David W. (Seabrook, TX); Clavenna, LeRoy R. (Baytown, TX); Gorbaty, Martin L. (Fanwood, NJ); Tsou, Joe M. (Galveston, TX)

    1980-01-01T23:59:59.000Z

    In a coal gasification operation or similar conversion process carried out in the presence of an alkali metal-containing catalyst wherein solid particles containing alkali metal residues are produced in the gasifier or similar reaction zone, alkali metal constitutents are recovered from the particles by withdrawing and passing the particles from the reaction zone to an alkali metal recovery zone in the substantial absence of molecular oxygen and treating the particles in the recovery zone with water or an aqueous solution in the substantial absence of molecular oxygen. The solution formed by treating the particles in the recovery zone will contain water-soluble alkali metal constituents and is recycled to the conversion process where the alkali metal constituents serve as at least a portion of the alkali metal constituents which comprise the alkali metal-containing catalyst. Preventing contact of the particles with oxygen as they are withdrawn from the reaction zone and during treatment in the recovery zone avoids the formation of undesirable alkali metal constituents in the aqueous solution produced in the recovery zone and insures maximum recovery of water-soluble alkali metal constituents from the alkali metal residues.

  6. Charge transport mechanisms of graphene/semiconductor Schottky barriers: A theoretical and experimental study

    SciTech Connect (OSTI)

    Zhong, Haijian; Liu, Zhenghui; Xu, Gengzhao; Shi, Lin; Fan, Yingmin; Yang, Hui [Suzhou Institute of Nano-Tech and Nano-Bionics, CAS, Suzhou 215123 (China); Xu, Ke, E-mail: kxu2006@sinano.ac.cn; Wang, Jianfeng; Ren, Guoqiang [Suzhou Institute of Nano-Tech and Nano-Bionics, CAS, Suzhou 215123 (China); Suzhou Nanowin Science and Technology Co., Ltd., Suzhou 215123 (China)

    2014-01-07T23:59:59.000Z

    Graphene has been proposed as a material for semiconductor electronic and optoelectronic devices. Understanding the charge transport mechanisms of graphene/semiconductor Schottky barriers will be crucial for future applications. Here, we report a theoretical model to describe the transport mechanisms at the interface of graphene and semiconductors based on conventional semiconductor Schottky theory and a floating Fermi level of graphene. The contact barrier heights can be estimated through this model and be close to the values obtained from the experiments, which are lower than those of the metal/semiconductor contacts. A detailed analysis reveals that the barrier heights are as the function of the interface separations and dielectric constants, and are influenced by the interfacial states of semiconductors. Our calculations show how this behavior of lowering barrier heights arises from the Fermi level shift of graphene induced by the charge transfer owing to the unique linear electronic structure.

  7. Method of passivating semiconductor surfaces

    DOE Patents [OSTI]

    Wanlass, Mark W. (Golden, CO)

    1990-01-01T23:59:59.000Z

    A method of passivating Group III-V or II-VI semiconductor compound surfaces. The method includes selecting a passivating material having a lattice constant substantially mismatched to the lattice constant of the semiconductor compound. The passivating material is then grown as an ultrathin layer of passivating material on the surface of the Group III-V or II-VI semiconductor compound. The passivating material is grown to a thickness sufficient to maintain a coherent interface between the ultrathin passivating material and the semiconductor compound. In addition, a device formed from such method is also disclosed.

  8. Method of passivating semiconductor surfaces

    DOE Patents [OSTI]

    Wanlass, M.W.

    1990-06-19T23:59:59.000Z

    A method is described for passivating Group III-V or II-VI semiconductor compound surfaces. The method includes selecting a passivating material having a lattice constant substantially mismatched to the lattice constant of the semiconductor compound. The passivating material is then grown as an ultrathin layer of passivating material on the surface of the Group III-V or II-VI semiconductor compound. The passivating material is grown to a thickness sufficient to maintain a coherent interface between the ultrathin passivating material and the semiconductor compound. In addition, a device formed from such method is also disclosed.

  9. Anomalous output characteristic shift for the n-type lateral diffused metal-oxide-semiconductor transistor with floating P-top layer

    SciTech Connect (OSTI)

    Liu, Siyang; Zhang, Chunwei; Sun, Weifeng, E-mail: swffrog@seu.edu.cn [National ASIC System Engineering Research Center, Southeast University, Nanjing 210096 (China); Su, Wei; Wang, Shaorong; Ma, Shulang; Huang, Yu [CSMC Technologies Corporation, Wuxi 214061 (China)

    2014-04-14T23:59:59.000Z

    Anomalous output characteristic shift of the n-type lateral diffused metal-oxide-semiconductor transistor with floating P-top layer is investigated. It shows that the linear drain current has obvious decrease when the output characteristic of fresh device is measured for two consecutive times. The charge pumping experiments demonstrate that the decrease is not from hot-carrier degradation. The reduction of cross section area for the current flowing, which results from the squeezing of the depletion region surrounding the P-top layer, is responsible for the shift. Consequently, the current capability of this special device should be evaluated by the second measured output characteristic.

  10. An in-depth noise model for giant magnetoresistance current sensors for circuit design and complementary metal–oxide–semiconductor integration

    SciTech Connect (OSTI)

    Roldán, A., E-mail: amroldan@ugr.es; Roldán, J. B. [Department of Electronics and Computer Technology, University of Granada (Spain); Reig, C. [Department of Electronic Engineering, University of Valencia (Spain); Cardoso, S. [INESC-MN and IN, Rua Alves Redol 9, 1000-029 Lisbon (Portugal); Instituto Superior Técnico (IST), Av. Rovisco Pais, 1000-029 Lisbon (Portugal); Cardoso, F. [INESC-MN and IN, Rua Alves Redol 9, 1000-029 Lisbon (Portugal); Ferreira, R. [International Iberian Nanotechnology Laboratory, Braga (Portugal); Freitas, P. P. [INESC-MN and IN, Rua Alves Redol 9, 1000-029 Lisbon (Portugal); International Iberian Nanotechnology Laboratory, Braga (Portugal)

    2014-05-07T23:59:59.000Z

    Full instrumentation bridges based on spin valve of giant magnetoresistance and magnetic tunnel junction devices have been microfabricated and experimentally characterized from the DC and noise viewpoint. A more realistic model of these devices was obtained in this work, an electrical and thermal model previously developed have been improved in such a way that noise effects are also included. We have implemented the model in a circuit simulator and reproduced the experimental measurements accurately. This provides a more realistic and complete tool for circuit design where magnetoresistive elements are combined with well-known complementary metal–oxide–semiconductor modules.

  11. Grain size effect on the semiconductor-metal phase transition characteristics of magnetron-sputtered VO{sub 2} thin films

    SciTech Connect (OSTI)

    Brassard, D.; Fourmaux, S.; Jean-Jacques, M.; Kieffer, J.C.; El Khakani, M. A. [Institut National de la Recherche Scientifique, INRS-Energie, Materiaux et Telecommunications, 1650, Boulevard Lionel-Boulet, C.P. 1020, Varennes, Quebec, J3X 1S2 (Canada)

    2005-08-01T23:59:59.000Z

    Single-phase vanadium dioxide (VO{sub 2}) thin films have been grown on Si{sub 3}N{sub 4}/Si substrates by means of a well-controlled magnetron sputtering process. The deposited VO{sub 2} films were found to exhibit a semiconductor-to-metal transition (SMT) at {approx}69 deg. C with a resistivity change as high as 3.2 decades. A direct and clear-cut correlation is established between the SMT characteristics (both amplitude and abruptness of the transition) of the VO{sub 2} films and their crystallite size.

  12. Low temperature production of large-grain polycrystalline semiconductors

    DOE Patents [OSTI]

    Naseem, Hameed A. (Fayetteville, AR); Albarghouti, Marwan (Loudonville, NY)

    2007-04-10T23:59:59.000Z

    An oxide or nitride layer is provided on an amorphous semiconductor layer prior to performing metal-induced crystallization of the semiconductor layer. The oxide or nitride layer facilitates conversion of the amorphous material into large grain polycrystalline material. Hence, a native silicon dioxide layer provided on hydrogenated amorphous silicon (a-Si:H), followed by deposited Al permits induced crystallization at temperatures far below the solid phase crystallization temperature of a-Si. Solar cells and thin film transistors can be prepared using this method.

  13. EEE 6397 Semiconductor Device Theory (Fall, 2014, 5th

    E-Print Network [OSTI]

    Fang, Yuguang "Michael"

    1 EEE 6397 Semiconductor Device Theory (Fall, 2014, 5th period MWF, BEN328) Goals: (1) Develop fundamental understanding on the device physics of the most important semiconductor devices, such as PN junctions, metal-semiconductor contacts, metal-oxide-semiconductor capacitors, and field-effect transistors

  14. Disordered electronic and magnetic systems - transition metal (Mn) and rare earth (Gd) doped amorphous group IV semiconductors (C, Si, Ge)

    E-Print Network [OSTI]

    Zeng, Li

    2007-01-01T23:59:59.000Z

    various transition or rare-earth metals provide a rich ?eldTransition Metal (Mn) and Rare Earth (Gd) Doped AmorphousTransition Metal (Mn) and Rare Earth (Gd) Doped Amorphous

  15. Methods for associating or dissociating guest materials with a metal organic framework, systems for associating or dissociating guest materials within a series of metal organic frameworks, thermal energy transfer assemblies, and methods for transferring thermal energy

    DOE Patents [OSTI]

    McGrail, B. Peter; Brown, Daryl R.; Thallapally, Praveen K.

    2014-08-05T23:59:59.000Z

    Methods for releasing associated guest materials from a metal organic framework are provided. Methods for associating guest materials with a metal organic framework are also provided. Methods are provided for selectively associating or dissociating guest materials with a metal organic framework. Systems for associating or dissociating guest materials within a series of metal organic frameworks are provided. Thermal energy transfer assemblies are provided. Methods for transferring thermal energy are also provided.

  16. Pressure-driven semiconductor-metal transition in intermediate-valence TmSe sub 1 minus x Te sub x and the concept of an excitonic insulator

    SciTech Connect (OSTI)

    Neuenschwander, J.; Wachter, P. (Laboratorium fuer Festkoerperphysik, Eidgenoessische Technische Hochschule Zuerich, CH-8093 Zuerich (Switzerland))

    1990-06-15T23:59:59.000Z

    This work studies the pressure-induced semiconductor-to-metal transition (SMT) in the TmSe-TmTe alloy system. This SMT is accompanied by a valence instability of the Tm ions. Single-crystalline semiconducting TmSe{sub 1{minus}{ital x}}Te{sub {ital x}} alloys are investigated under high pressure at low temperatures. Measurements of electrical resistivity, magnetic susceptibility, neutron diffraction, and optical properties are presented and discussed. A very unusual peak structure in the resistivity-pressure relation is observed at low temperatures. A discussion of the novel feature involves the concept of an excitonic insulator and {ital f}-{ital d} hybridization. The magnetic behavior of the compounds is significantly influenced by the SMT. This is thought to be mainly due to the additional coupling between the magnetic moments of Tm via free carriers which are present in the metallic state.

  17. Temperature dependent junction capacitance-voltage characteristics of Ni embedded TiN/SiO{sub 2}/p-Si metal–insulator–semiconductor structure

    SciTech Connect (OSTI)

    Panda, J.; Nath, T. K., E-mail: tnath@phy.iitkgp.ernet.in [Department of Physics and Meteorology, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302 (India); Chattopadhyay, S. [Department of Physics and Meteorology, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302 (India); Amity Institute of Nano Technology, Amity University, Sector-125, Noida, Uttar Pradesh 201313 (India)

    2013-12-14T23:59:59.000Z

    This work presents the junction capacitance–voltage characteristics of highly textured/epitaxial Ni nanoparticle embedded in TiN matrix (TiN(Ni)) metal-insulator-semiconductor TiN(Ni)/SiO{sub 2}/p-Si (100) heterojunction in the temperature range of 10–300?K. This heterojunction behaves as metal-semiconductor junction with unavoidable leakage through native oxide SiO{sub 2} layer. The clockwise hysteresis loop has been observed in the capacitance-voltage characteristics measured at various frequencies mainly due to presence of trap centers at the TiN(Ni)/SiO{sub 2} interface and these are temperature dependent. The spin-dependent trap charge effect at the interface influences the quadratic nature of the capacitance with magnetic field. The junction magnetocapacitance (JMC) is observed to be dependent on both temperature and frequency. The highest JMC of this heterojunction has been observed at 200?K at higher frequencies (100?kHz–1?MHz). It is found that there is not much effect of band structure modification under magnetic field causing the JMC.

  18. Ceramic/metal and A15/metal superconducting composite materials exploiting the superconducting proximity effect and method of making the same

    DOE Patents [OSTI]

    Holcomb, Matthew J. (Manhattan Beach, CA)

    1999-01-01T23:59:59.000Z

    A composite superconducting material made of coated particles of ceramic superconducting material and a metal matrix material. The metal matrix material fills the regions between the coated particles. The coating material is a material that is chemically nonreactive with the ceramic. Preferably, it is silver. The coating serves to chemically insulate the ceramic from the metal matrix material. The metal matrix material is a metal that is susceptible to the superconducting proximity effect. Preferably, it is a NbTi alloy. The metal matrix material is induced to become superconducting by the superconducting proximity effect when the temperature of the material goes below the critical temperature of the ceramic. The material has the improved mechanical properties of the metal matrix material. Preferably, the material consists of approximately 10% NbTi, 90% coated ceramic particles (by volume). Certain aspects of the material and method will depend upon the particular ceramic superconductor employed. An alternative embodiment of the invention utilizes A15 compound superconducting particles in a metal matrix material which is preferably a NbTi alloy.

  19. Design, Synthesis, and Characterization of Porous Metal-Organic Materials

    E-Print Network [OSTI]

    Park, Jinhee

    2013-04-19T23:59:59.000Z

    Isophthalic Acid SBUs Secondary Building Units srMOP Stimuli-Responsive Metal-Organic Polyhedra viii STP Standard Temperature and Pressure TEA Triethylamine TGA Thermal Gravimetric Analysis UMC Unsaturated Metal Center UV Ultraviolet Vis Visible...).. ................. 74 IV-9 Nonlinear curve fitting of CH4 adsorption isotherms at 273 K and 295 K (a) and CH4 heat of adsorption for PCN-124 (b). ................................ 75 V-1 The trans to cis isomerization of the ligand induced by UV...

  20. Ordered porous mesostructured materials from nanoparticle-block copolymer self-assembly

    DOE Patents [OSTI]

    Warren, Scott; Wiesner, Ulrich; DiSalvo, Jr., Francis J

    2013-10-29T23:59:59.000Z

    The invention provides mesostructured materials and methods of preparing mesostructured materials including metal-rich mesostructured nanoparticle-block copolymer hybrids, porous metal-nonmetal nanocomposite mesostructures, and ordered metal mesostructures with uniform pores. The nanoparticles can be metal, metal alloy, metal mixture, intermetallic, metal-carbon, metal-ceramic, semiconductor-carbon, semiconductor-ceramic, insulator-carbon or insulator-ceramic nanoparticles, or combinations thereof. A block copolymer/ligand-stabilized nanoparticle solution is cast, resulting in the formation of a metal-rich (or semiconductor-rich or insulator-rich) mesostructured nanoparticle-block copolymer hybrid. The hybrid is heated to an elevated temperature, resulting in the formation of an ordered porous nanocomposite mesostructure. A nonmetal component (e.g., carbon or ceramic) is then removed to produce an ordered mesostructure with ordered and large uniform pores.

  1. The synthesis of inorganic semiconductor nanocrystalline materials for the purpose of creating hybrid organic/inorganic light-emitting devices

    E-Print Network [OSTI]

    Steckel, Jonathan S. (Jonathan Stephen)

    2006-01-01T23:59:59.000Z

    Colloidal semiconductor nanocrystals (NCs) or quantum dots (QDs) can be synthesized to efficiently emit light from the ultraviolet, across the entire visible spectrum, and into the near infrared. This is now possible due ...

  2. Electrode materials for the electrolysis of metal oxides

    E-Print Network [OSTI]

    Cooper, Benjamin D

    2006-01-01T23:59:59.000Z

    Carbon, tungsten, platinum, and iridium were examined as candidate anode materials for an electrolytic cell. The materials were pre-selected to endure high process temperatures and were characterized for inertness and high ...

  3. Stabilized Lithium Metal Powder, Enabling Material and Revolutionary...

    Broader source: Energy.gov (indexed) [DOE]

    LiCoO 2 cathodes and, when paired with advanced anode materials, such as silicon composite material, the resulting cell will still not meet the energy density requirements,...

  4. Comparison of Nonprecious Metal Cathode Materials for Methane Production by Electromethanogenesis

    E-Print Network [OSTI]

    contributed to electromethanogenic gas production. KEYWORDS: Biocathode, Carbon capturing and sequestration generation, we examined several cathode materials: plain graphite blocks, graphite blocks coated with carbon black or carbon black containing metals (platinum, stainless steel or nickel) or insoluble minerals

  5. Investigation on Aluminum-Based Amorphous Metallic Glass as New Anode Material in Lithium Ion Batteries

    E-Print Network [OSTI]

    Meng, Shirley Y.

    Aluminum based amorphous metallic glass powders were produced and tested as the anode materials for the lithium ion rechargeable batteries. Ground Al??Ni₁?La₁? was found to have a ...

  6. Superhard composite materials including compounds of carbon and nitrogen deposited on metal and metal nitride, carbide and carbonitride

    DOE Patents [OSTI]

    Wong, M.S.; Li, D.; Chung, Y.W.; Sproul, W.D.; Chu, X.; Barnett, S.A.

    1998-07-07T23:59:59.000Z

    A composite material having high hardness comprises a carbon nitrogen compound, such as CN{sub x} where x is greater than 0.1 and up to 1.33, deposited on a metal or metal compound selected to promote deposition of substantially crystalline CN{sub x}. The carbon nitrogen compound is deposited on a crystal plane of the metal or metal compound sufficiently lattice-matched with a crystal plane of the carbon nitrogen compound that the carbon nitrogen compound is substantially crystalline. A plurality of layers of the compounds can be formed in alternating sequence to provide a multi-layered, superlattice coating having a coating hardness in the range of 45--55 GPa, which corresponds to the hardness of a BN coating and approaches that of a diamond coating. 10 figs.

  7. Superhard composite materials including compounds of carbon and nitrogen deposited on metal and metal nitride, carbide and carbonitride

    DOE Patents [OSTI]

    Wong, Ming-Show (Northbrook, IL); Li, Dong (Evanston, IL); Chung, Yip-Wah (Wilmette, IL); Sproul, William D. (Palantine, IL); Chu, Xi (Evanston, IL); Barnett, Scott A. (Evanston, IL)

    1998-01-01T23:59:59.000Z

    A composite material having high hardness comprises a carbon nitrogen compound, such as CN.sub.x where x is greater than 0.1 and up to 1.33, deposited on a metal or metal compound selected to promote deposition of substantially crystalline CN.sub.x. The carbon nitrogen compound is deposited on a crystal plane of the metal or metal compound sufficiently lattice-matched with a crystal plane of the carbon nitrogen compound that the carbon nitrogen compound is substantially crystalline. A plurality of layers of the compounds can be formed in alternating sequence to provide a multi-layered, superlattice coating having a coating hardness in the range of 45-55 GPa, which corresponds to the hardness of a BN coating and approaches that of a diamond coating.

  8. Superhard composite materials including compounds of carbon and nitrogen deposited on metal and metal nitride carbide and carbonitride

    DOE Patents [OSTI]

    Wong, M.S.; Li, D.; Chung, Y.W.; Sproul, W.D.; Xi Chu; Barnett, S.A.

    1998-03-10T23:59:59.000Z

    A composite material having high hardness comprises a carbon nitrogen compound, such as CN{sub x} where x is greater than 0.1 and up to 1.33, deposited on a metal or metal compound selected to promote deposition of substantially crystalline CN{sub x}. The carbon nitrogen compound is deposited on a crystal plane of the metal or metal compound sufficiently lattice-matched with a crystal plane of the carbon nitrogen compound that the carbon nitrogen compound is substantially crystalline. A plurality of layers of the compounds can be formed in alternating sequence to provide a multi-layered, superlattice coating having a coating hardness in the range of 45--55 GPa, which corresponds to the hardness of a BN coating and approaches that of a diamond coating. 10 figs.

  9. Superhard composite materials including compounds of carbon and nitrogen deposited on metal and metal nitride carbide and carbonitride

    DOE Patents [OSTI]

    Wong, Ming-Show (Northbrook, IL); Li, Dong (Evanston, IL); Chung, Yin-Wah (Wilmette, IL); Sproul, William D. (Palantine, IL); Chu, Xi (Evanston, IL); Barnett, Scott A. (Evanston, IL)

    1998-01-01T23:59:59.000Z

    A composite material having high hardness comprises a carbon nitrogen compound, such as CN.sub.x where x is greater than 0.1 and up to 1.33, deposited on a metal or metal compound selected to promote deposition of substantially crystalline CN.sub.x. The carbon nitrogen compound is deposited on a crystal plane of the metal or metal compound sufficiently lattice-matched with a crystal plane of the carbon nitrogen compound that the carbon nitrogen compound is substantially crystalline. A plurality of layers of the compounds can be formed in alternating sequence to provide a multi-layered, superlattice coating having a coating hardness in the range of 45-55 GPa, which corresponds to the hardness of a BN coating and approaches that of a diamond coating.

  10. Effects of Dopant Metal Variation and Material Synthesis Method on the Material Properties of Mixed Metal Ferrites in Yttria Stabilized Zirconia for Solar Thermochemical Fuel Production

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Leonard, Jeffrey; Reyes, Nichole; Allen, Kyle M.; Randhir, Kelvin; Li, Like; AuYeung, Nick; Grunewald, Jeremy; Rhodes, Nathan; Bobek, Michael; Klausner, James F.

    2015-01-01T23:59:59.000Z

    Mixed metal ferrites have shown much promise in two-step solar-thermochemical fuel production. Previous work has typically focused on evaluating a particular metal ferrite produced by a particular synthesis process, which makes comparisons between studies performed by independent researchers difficult. A comparative study was undertaken to explore the effects different synthesis methods have on the performance of a particular material during redox cycling using thermogravimetry. This study revealed that materials made via wet chemistry methods and extended periods of high temperature calcination yield better redox performance. Differences in redox performance between materials made via wet chemistry methods were minimal and thesemore »demonstrated much better performance than those synthesized via the solid state method. Subsequently, various metal ferrite samples (NiFe2O4, MgFe2O4, CoFe2O4, and MnFe2O4) in yttria stabilized zirconia (8YSZ) were synthesized via coprecipitation and tested to determine the most promising metal ferrite combination. It was determined that 10?wt.% CoFe2O4in 8YSZ produced the highest and most consistent yields of O2and CO. By testing the effects of synthesis methods and dopants in a consistent fashion, those aspects of ferrite preparation which are most significant can be revealed. More importantly, these insights can guide future efforts in developing the next generation of thermochemical fuel production materials.« less

  11. Metallization and insulization during impact

    SciTech Connect (OSTI)

    Gilman, J.J.

    1992-10-01T23:59:59.000Z

    It is pointed out that the large strains produced by hypervelocity impacts can be expected to produce dramatic changes in the chemical bonding (electronic structures) of materials. This will change the mechanical behavior towards increased ductility when a semiconductor is compressed until it becomes metallic; and towards increased brittleness when a transition metal is expanded so as to localize its d-band electrons. Both isotropic compression (expansion) and shear strains can cause these transformations. Critical deformation criteria are given based on the observed cubic to tetragonal transformations in compressed semiconductors.

  12. Waveguides in three-dimensional metallic photonic band-gap materials

    SciTech Connect (OSTI)

    Sigalas, M.M.; Biswas, R.; Ho, K.M.; Soukoulis, C.M. [Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011 (United States)] [Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011 (United States); Crouch, D.D. [Advanced Electromagnetic Technologies Center, Raytheon Corporation, Rancho Cucamonga, California 91729 (United States)] [Advanced Electromagnetic Technologies Center, Raytheon Corporation, Rancho Cucamonga, California 91729 (United States)

    1999-08-01T23:59:59.000Z

    We theoretically investigate waveguide structures in three-dimensional metallic photonic band-gap (MPBG) materials. The MPBG materials used in this study consist of a three-dimensional mesh of metallic wires embedded in a dielectric. An {ital L}-shaped waveguide is created by removing part of the metallic wires. Using finite difference time domain simulations, we found that an 85{percent} transmission efficiency can be achieved through the 90{degree} bend with just three unit cell thickness MPBG structures. thinsp {copyright} {ital 1999} {ital The American Physical Society}

  13. Low trap states in in situ SiN{sub x}/AlN/GaN metal-insulator-semiconductor structures grown by metal-organic chemical vapor deposition

    SciTech Connect (OSTI)

    Lu, Xing; Ma, Jun; Jiang, Huaxing; Liu, Chao; Lau, Kei May, E-mail: eekmlau@ust.hk [Department of Electronic and Computer Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon (Hong Kong)

    2014-09-08T23:59:59.000Z

    We report the use of SiN{sub x} grown in situ by metal-organic chemical vapor deposition as the gate dielectric for AlN/GaN metal-insulator-semiconductor (MIS) structures. Two kinds of trap states with different time constants were identified and characterized. In particular, the SiN{sub x}/AlN interface exhibits remarkably low trap state densities in the range of 10{sup 11}–10{sup 12?}cm{sup ?2}eV{sup ?1}. Transmission electron microscopy and X-ray photoelectron spectroscopy analyses revealed that the in situ SiN{sub x} layer can provide excellent passivation without causing chemical degradation to the AlN surface. These results imply the great potential of in situ SiN{sub x} as an effective gate dielectric for AlN/GaN MIS devices.

  14. Variable temperature semiconductor film deposition

    DOE Patents [OSTI]

    Li, Xiaonan (Golden, CO); Sheldon, Peter (Lakewood, CO)

    1998-01-01T23:59:59.000Z

    A method of depositing a semiconductor material on a substrate. The method sequentially comprises (a) providing the semiconductor material in a depositable state such as a vapor for deposition on the substrate; (b) depositing the semiconductor material on the substrate while heating the substrate to a first temperature sufficient to cause the semiconductor material to form a first film layer having a first grain size; (c) continually depositing the semiconductor material on the substrate while cooling the substrate to a second temperature sufficient to cause the semiconductor material to form a second film layer deposited on the first film layer and having a second grain size smaller than the first grain size; and (d) raising the substrate temperature, while either continuing or not continuing to deposit semiconductor material to form a third film layer, to thereby anneal the film layers into a single layer having favorable efficiency characteristics in photovoltaic applications. A preferred semiconductor material is cadmium telluride deposited on a glass/tin oxide substrate already having thereon a film layer of cadmium sulfide.

  15. Variable temperature semiconductor film deposition

    DOE Patents [OSTI]

    Li, X.; Sheldon, P.

    1998-01-27T23:59:59.000Z

    A method of depositing a semiconductor material on a substrate is disclosed. The method sequentially comprises (a) providing the semiconductor material in a depositable state such as a vapor for deposition on the substrate; (b) depositing the semiconductor material on the substrate while heating the substrate to a first temperature sufficient to cause the semiconductor material to form a first film layer having a first grain size; (c) continually depositing the semiconductor material on the substrate while cooling the substrate to a second temperature sufficient to cause the semiconductor material to form a second film layer deposited on the first film layer and having a second grain size smaller than the first grain size; and (d) raising the substrate temperature, while either continuing or not continuing to deposit semiconductor material to form a third film layer, to thereby anneal the film layers into a single layer having favorable efficiency characteristics in photovoltaic applications. A preferred semiconductor material is cadmium telluride deposited on a glass/tin oxide substrate already having thereon a film layer of cadmium sulfide.

  16. Strained Sistrained Ge dual-channel heterostructures on relaxed Si0.5Ge0.5 for symmetric mobility p-type and n-type metal-oxide-semiconductor

    E-Print Network [OSTI]

    Strained SiÕstrained Ge dual-channel heterostructures on relaxed Si0.5Ge0.5 for symmetric mobility By growing heterostructures that combine a surface strained Si layer with a buried strained Ge layer on Si0.5Ge0.5 , we have fabricated metal-oxide-semiconductor field-effect transistors with mobility

  17. RADIOACTIVE MATERIAL SHIPPING PACKAGINGS AND METAL TO METAL SEALS FOUND IN THE CLOSURES OF CONTAINMENT VESSELS INCORPORATING CONE SEAL CLOSURES

    SciTech Connect (OSTI)

    Loftin, B; Glenn Abramczyk, G; Allen Smith, A

    2007-06-06T23:59:59.000Z

    The containment vessels for the Model 9975 radioactive material shipping packaging employ a cone-seal closure. The possibility of a metal-to-metal seal forming between the mating conical surfaces, independent of the elastomer seals, has been raised. It was postulated that such an occurrence would compromise the containment vessel hydrostatic and leakage tests. The possibility of formation of such a seal has been investigated by testing and by structural and statistical analyses. The results of the testing and the statistical analysis demonstrate and procedural changes ensure that hydrostatic proof and annual leakage testing can be accomplished to the appropriate standards.

  18. Anomalous optical switching and thermal hysteresis during semiconductor-metal phase transition of VO{sub 2} films on Si substrate

    SciTech Connect (OSTI)

    Leahu, G.; Li Voti, R., E-mail: roberto.livoti@uniroma1.it; Sibilia, C.; Bertolotti, M. [Dipartimento di Scienze di Base ed Applicate per l'Ingegneria, Sapienza Università di Roma, via A. Scarpa 16, 00161 Roma (Italy)] [Dipartimento di Scienze di Base ed Applicate per l'Ingegneria, Sapienza Università di Roma, via A. Scarpa 16, 00161 Roma (Italy)

    2013-12-02T23:59:59.000Z

    We present a detailed infrared study of the semiconductor-to-metal transition (SMT) in a vanadium dioxide (VO{sub 2}) film deposited on silicon wafer. The VO{sub 2} phase transition is studied in the mid-infrared region by analyzing the transmittance and the reflectance measurements, and the calculated emissivity. The reflectance has been measured in two configurations: from the side of the VO{sub 2} film and from that of Si wafer. The results show a strong asymmetry between the emissivity in the two configurations, and the fact that the emissivity dynamic range from the silicon side is twice as large than that from the VO{sub 2} side. The temperature behaviour of the emissivity during the SMT put into evidence the phenomenon of the anomalous absorption in VO{sub 2}, which has been explained by applying the Maxwell Garnett effective medium approximation theory.

  19. Spectroscopy of semiconductor materials

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del Sol HomeFacebookScholarship Fund3Biology|SolarSpeakersSpectroscopy| MIT-HarvardAg 3

  20. A continuum constitutive model for amorphous metallic materials

    E-Print Network [OSTI]

    Su, Cheng, Ph. D. Massachusetts Institute of Technology

    2007-01-01T23:59:59.000Z

    A finite-deformation, Coulomb-Mohr type constitutive theory for the elastic-viscoplastic response of pressure-sensitive and plastically-dilatant isotropic materials has been developed. The constitutive model has been ...

  1. New binding materials for metal hydride electrodes which permit good recyclability

    SciTech Connect (OSTI)

    Hara, T.; Yasuda, N. (Japan Synthetic Rubber Co., Ltd., Yokkaichi (Japan). Development Center); Takeuchi, Y. (Japan Synthetic Rubber Co., Ltd., Tokyo (Japan). Electronics Project Dept.); Sakai, T.; Uchiyama, A.; Miyamura, H.; Kuriyama, N.; Ishikawa, H. (Government Industrial Research Inst., Osaka (Japan))

    1993-09-01T23:59:59.000Z

    Thermoplastic elastomers such as styrene-butadiene-styrene block copolymer (SBS) and styrene-ethylene/butylene-styrene block copolymer (SEBS) were used successfully as binding materials for metal hydride (MH) electrodes of a nickel-metal hydride battery. These binding materials have a rubber-like nature and are soluble in organic solvents. It was easy to remove the alloy powder from a used electrode for recycling. The battery performance depended on both the kind and amount of binding materials. The best discharge capacity and rate capability were obtained for MH electrodes containing 2--5 weight percent (w/o) SEBS. The particle size distributions for the alloy were examined successfully.

  2. Internal gettering by metal alloy clusters

    DOE Patents [OSTI]

    Buonassisi, Anthony (San Diego, CA); Heuer, Matthias (Berkeley, CA); Istratov, Andrei A. (Albany, CA); Pickett, Matthew D. (Berkeley, CA); Marcus, Mathew A. (Berkeley, CA); Weber, Eicke R. (Piedmont, CA)

    2010-07-27T23:59:59.000Z

    The present invention relates to the internal gettering of impurities in semiconductors by metal alloy clusters. In particular, intermetallic clusters are formed within silicon, such clusters containing two or more transition metal species. Such clusters have melting temperatures below that of the host material and are shown to be particularly effective in gettering impurities within the silicon and collecting them into isolated, less harmful locations. Novel compositions for some of the metal alloy clusters are also described.

  3. Electrolyte materials containing highly dissociated metal ion salts

    DOE Patents [OSTI]

    Lee, Hung-Sui (East Setauket, NY); Geng, Lin (Coram, NY); Skotheim, Terje A. (Shoreham, NY)

    1996-07-23T23:59:59.000Z

    The present invention relates to metal ion salts which can be used in electrolytes for producing electrochemical devices, including both primary and secondary batteries, photoelectrochemical cells and electrochromic displays. The salts have a low energy of dissociation and may be dissolved in a suitable polymer to produce a polymer solid electrolyte or in a polar aprotic liquid solvent to produce a liquid electrolyte. The anion of the salts may be covalently attached to polymer backbones to produce polymer solid electrolytes with exclusive cation conductivity.

  4. Electrolyte materials containing highly dissociated metal ion salts

    DOE Patents [OSTI]

    Lee, H.S.; Geng, L.; Skotheim, T.A.

    1996-07-23T23:59:59.000Z

    The present invention relates to metal ion salts which can be used in electrolytes for producing electrochemical devices, including both primary and secondary batteries, photoelectrochemical cells and electrochromic displays. The salts have a low energy of dissociation and may be dissolved in a suitable polymer to produce a polymer solid electrolyte or in a polar aprotic liquid solvent to produce a liquid electrolyte. The anion of the salts may be covalently attached to polymer backbones to produce polymer solid electrolytes with exclusive cation conductivity. 2 figs.

  5. High Metal Removal Rate Process for Machining Difficult Materials

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(Fact Sheet), GeothermalGridHYDROGEN TOTechnologyHigh EfficiencyMetal Removal

  6. High Metal Removal Rate Process for Machining Difficult Materials

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(Fact Sheet), GeothermalGridHYDROGEN TOTechnologyHigh EfficiencyMetal RemovalHybrid

  7. High Metal Removal Rate Process for Machining Difficult Materials

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(Fact Sheet), GeothermalGridHYDROGEN TOTechnologyHigh EfficiencyMetal

  8. Isotopically controlled semiconductors

    E-Print Network [OSTI]

    Haller, Eugene E.

    2006-01-01T23:59:59.000Z

    16 Isotopically Controlled Semiconductors Eugene E. Hallerof isotopically engineered semiconductors; for outstandingisotopically controlled semiconductor crystals. This article

  9. Microporous Materials Strategies for Hydrogen Storage in MetalOrganic

    E-Print Network [OSTI]

    Yaghi, Omar M.

    efficiency fuel-cell power sources. The vehicles should have a similar range (480 km or 300 miles), operate times the gravimetric energy density of petrol, and fuel cells are expected to perform at least twice at improving hydrogen uptake in these materials is presented. These strategies include the optimization of pore

  10. Master of Science project in advanced computational material physics Electrical conductivity of the correlated metal LaNiO3

    E-Print Network [OSTI]

    Hellsing, Bo

    Master of Science project in advanced computational material physics Electrical conductivity of the correlated metal LaNiO3 Lanthanum nickelate, LaNiO3, belongs to the class of materials named strongly correlated metals. Several properties of these materials can not be understood based on standard

  11. Chemistry and Applications of Metal-Organic Materials

    E-Print Network [OSTI]

    Zhao, Dan

    2012-02-14T23:59:59.000Z

    ) and applicable pressure (less than 100 atm). Note that these are the goals for the system including container and any necessary accessories, the hydrogen storage capacity of the material itself should be even higher. A safe and effective hydrogen storage.... In solid-state storage systems, a hydrogen atom/molecule either forms a strong chemical bond to a solid support (chemisorption) or interacts weakly with a sorbent (physisorption). In chemisorption, dihydrogen molecules split into hydrogen atoms upon...

  12. Treatment of precious metal bearing recycled materials at UM`s Hoboken smelter

    SciTech Connect (OSTI)

    Vanbellen, F. [Union Miniere, Hoboken (Belgium). Business Unit Hoboken

    1995-12-31T23:59:59.000Z

    In Union Miniere`s Hoboken smelter and refinery for complex non-ferrous materials, the treatment of recycling products, containing precious metals, occupies a dominant place. For all feed materials, the first step, prior to their treatment, is to classify them in order to select an accurate and economical procedure for sampling as well as to dispatch them to the optimal process scheme. More than 150 different procedures for sampling are commonly used. The most important ones are briefly discussed in the paper. Precious metals bearing recycling materials vary widely with respect to their physical aspect, their chemical composition and the value of their precious metal content. All these parameters are taken into consideration to select the most appropriate process among the multiple possibilities of Union Miniere`s flexible integrated flow-sheet. Different stages of the operations as well as the main flow-sheets are described. Specific hydrometallurgical and pyrometallurgical processes have been developed for the extraction and the refining of: precious metals -- Ag, Au, Pt, Pd, Rh; base metals -- Pb, Cu, Sb, Sn, Bi; and special metals -- Se, In, Te.

  13. High-temperature stable W/GaAs interface and application to metal--semiconductor field-effect transistors and digital circuits

    SciTech Connect (OSTI)

    Josefowicz, J.Y.; Rensch, D.B.

    1987-11-01T23:59:59.000Z

    The thermal stability of the physical, chemical, and electrical properties of W thin films sputter deposited on GaAs were investigated. A variety of characterization methods, including thin film stress analysis, Auger analysis, Rutherford backscattering spectrometry (RBS) analysis, and Schottky barrier measurements showed that the W/GaAs interface remains stable after high-temperature furnace annealing at 900 /sup 0/C for 15 min or rapid-lamp annealing at 1000 /sup 0/C for 11 s. Some refractory metal compounds were also investigated, including, WSi, WN/sub x/, and TaSi/sub x/. Pure W films produced the best Schottky diode characteristics. The average Schottky barrier height was 0.70 +- 0.009 V across a 2-in wafer after furnace annealing at 800 /sup 0/C/15 min. Pure W self-aligned gate (SAG) metal-semiconductor field-effect transistors (MESFET) and digital circuits were also fabricated. Transconductances as high as 300 mS/mm (L/sub g/ = 1.0 ..mu..m) were measured for enhancement mode SAG MESFET's. Circuits were fabricated with SAG MESFET enhancement-resistor mode logic using pure W gates, including ring oscillators, with gate delay as low as 25 ps and divide-by-eight circuits that functioned at a frequency >1 GHz.

  14. High-Temperature Thermoelectric Characterization of IIIV Semiconductor Thin Films by Oxide Bonding

    E-Print Network [OSTI]

    High-Temperature Thermoelectric Characterization of III­V Semiconductor Thin Films by Oxide Bonding and measurement method utilizing a SiO2­SiO2 covalent bonding technique is presented for high-temperature surface passivation, and metallization with a Ti-W-N diffusion barrier. A thermoelectric material, thin

  15. High temperature thermoelectric characterization of III-V semiconductor thin films by oxide bonding

    E-Print Network [OSTI]

    Bowers, John

    bonding Je-Hyeong Bahka) , Gehong Zenga) , Joshua M. O. Zide b) , Hong Luc) , Rajeev Singhd) , Di Lianga bonding technique is developed for high temperature thermoelectric characterization of the thin film III-W-N diffusion barrier. A thermoelectric material, thin film ErAs:InGaAlAs metal/semiconductor nanocomposite

  16. Secondary cell with orthorhombic alkali metal/manganese oxide phase active cathode material

    DOE Patents [OSTI]

    Doeff, M.M.; Peng, M.Y.; Ma, Y.; Visco, S.J.; DeJonghe, L.C.

    1996-09-24T23:59:59.000Z

    An alkali metal manganese oxide secondary cell is disclosed which can provide a high rate of discharge, good cycling capabilities, good stability of the cathode material, high specific energy (energy per unit of weight) and high energy density (energy per unit volume). The active material in the anode is an alkali metal and the active material in the cathode comprises an orthorhombic alkali metal manganese oxide which undergoes intercalation and deintercalation without a change in phase, resulting in a substantially linear change in voltage with change in the state of charge of the cell. The active material in the cathode is an orthorhombic structure having the formula M{sub x}Z{sub y}Mn{sub (1{minus}y)}O{sub 2}, where M is an alkali metal; Z is a metal capable of substituting for manganese in the orthorhombic structure such as iron, cobalt or titanium; x ranges from about 0.2 in the fully charged state to about 0.75 in the fully discharged state, and y ranges from 0 to 60 atomic %. Preferably, the cell is constructed with a solid electrolyte, but a liquid or gelatinous electrolyte may also be used in the cell. 11 figs.

  17. Secondary cell with orthorhombic alkali metal/manganese oxide phase active cathode material

    DOE Patents [OSTI]

    Doeff, Marca M. (Hayward, CA); Peng, Marcus Y. (Cupertino, CA); Ma, Yanping (Albany, CA); Visco, Steven J. (Berkeley, CA); DeJonghe, Lutgard C. (Lafayette, CA)

    1996-01-01T23:59:59.000Z

    An alkali metal manganese oxide secondary cell is disclosed which can provide a high rate of discharge, good cycling capabilities, good stability of the cathode material, high specific energy (energy per unit of weight) and high energy density (energy per unit volume). The active material in the anode is an alkali metal and the active material in the cathode comprises an orthorhombic alkali metal manganese oxide which undergoes intercalation and deintercalation without a change in phase, resulting in a substantially linear change in voltage with change in the state of charge of the cell. The active material in the cathode is an orthorhombic structure having the formula M.sub.x Z.sub.y Mn.sub.(1-y) O.sub.2, where M is an alkali metal; Z is a metal capable of substituting for manganese in the orthorhombic structure such as iron, cobalt or titanium; x ranges from about 0.2 in the fully charged state to about 0.75 in the fully discharged state, and y ranges from 0 to 60 atomic %. Preferably, the cell is constructed with a solid electrolyte, but a liquid or gelatinous electrolyte may also be used in the cell.

  18. Joining of dissimilar materials

    DOE Patents [OSTI]

    Tucker, Michael C; Lau, Grace Y; Jacobson, Craig P

    2012-10-16T23:59:59.000Z

    A method of joining dissimilar materials having different ductility, involves two principal steps: Decoration of the more ductile material's surface with particles of a less ductile material to produce a composite; and, sinter-bonding the composite produced to a joining member of a less ductile material. The joining method is suitable for joining dissimilar materials that are chemically inert towards each other (e.g., metal and ceramic), while resulting in a strong bond with a sharp interface between the two materials. The joining materials may differ greatly in form or particle size. The method is applicable to various types of materials including ceramic, metal, glass, glass-ceramic, polymer, cermet, semiconductor, etc., and the materials can be in various geometrical forms, such as powders, fibers, or bulk bodies (foil, wire, plate, etc.). Composites and devices with a decorated/sintered interface are also provided.

  19. Role of the dielectric for the charging dynamics of the dielectric/barrier interface in AlGaN/GaN based metal-insulator-semiconductor structures under forward gate bias stress

    SciTech Connect (OSTI)

    Lagger, P., E-mail: peter.lagger@infineon.com [Infineon Technologies Austria AG, Siemensstraße 2, 9500 Villach (Austria); Institute of Solid State Electronics, Vienna University of Technology, Floragasse 7, 1040 Wien (Austria); Steinschifter, P.; Reiner, M.; Stadtmüller, M.; Denifl, G.; Ostermaier, C. [Infineon Technologies Austria AG, Siemensstraße 2, 9500 Villach (Austria); Naumann, A.; Müller, J.; Wilde, L.; Sundqvist, J. [Fraunhofer IPMS-CNT, Königsbrücker Straße 178, 01099 Dresden (Germany); Pogany, D. [Institute of Solid State Electronics, Vienna University of Technology, Floragasse 7, 1040 Wien (Austria)

    2014-07-21T23:59:59.000Z

    The high density of defect states at the dielectric/III-N interface in GaN based metal-insulator-semiconductor structures causes tremendous threshold voltage drifts, ?V{sub th}, under forward gate bias conditions. A comprehensive study on different dielectric materials, as well as varying dielectric thickness t{sub D} and barrier thickness t{sub B}, is performed using capacitance-voltage analysis. It is revealed that the density of trapped electrons, ?N{sub it}, scales with the dielectric capacitance under spill-over conditions, i.e., the accumulation of a second electron channel at the dielectric/AlGaN barrier interface. Hence, the density of trapped electrons is defined by the charging of the dielectric capacitance. The scaling behavior of ?N{sub it} is explained universally by the density of accumulated electrons at the dielectric/III-N interface under spill-over conditions. We conclude that the overall density of interface defects is higher than what can be electrically measured, due to limits set by dielectric breakdown. These findings have a significant impact on the correct interpretation of threshold voltage drift data and are of relevance for the development of normally off and normally on III-N/GaN high electron mobility transistors with gate insulation.

  20. Coated semiconductor devices for neutron detection

    DOE Patents [OSTI]

    Klann, Raymond T. (Bolingbrook, IL); McGregor, Douglas S. (Whitmore Lake, MI)

    2002-01-01T23:59:59.000Z

    A device for detecting neutrons includes a semi-insulated bulk semiconductor substrate having opposed polished surfaces. A blocking Schottky contact comprised of a series of metals such as Ti, Pt, Au, Ge, Pd, and Ni is formed on a first polished surface of the semiconductor substrate, while a low resistivity ("ohmic") contact comprised of metals such as Au, Ge, and Ni is formed on a second, opposed polished surface of the substrate. In one embodiment, n-type low resistivity pinout contacts comprised of an Au/Ge based eutectic alloy or multi-layered Pd/Ge/Ti/Au are also formed on the opposed polished surfaces and in contact with the Schottky and ohmic contacts. Disposed on the Schottky contact is a neutron reactive film, or coating, for detecting neutrons. The coating is comprised of a hydrogen rich polymer, such as a polyolefin or paraffin; lithium or lithium fluoride; or a heavy metal fissionable material. By varying the coating thickness and electrical settings, neutrons at specific energies can be detected. The coated neutron detector is capable of performing real-time neutron radiography in high gamma fields, digital fast neutron radiography, fissile material identification, and basic neutron detection particularly in high radiation fields.

  1. Hybrid metal organic scintillator materials system and particle detector

    DOE Patents [OSTI]

    Bauer, Christina A.; Allendorf, Mark D.; Doty, F. Patrick; Simmons, Blake A.

    2011-07-26T23:59:59.000Z

    We describe the preparation and characterization of two zinc hybrid luminescent structures based on the flexible and emissive linker molecule, trans-(4-R,4'-R') stilbene, where R and R' are mono- or poly-coordinating groups, which retain their luminescence within these solid materials. For example, reaction of trans-4,4'-stilbenedicarboxylic acid and zinc nitrate in the solvent dimethylformamide (DMF) yielded a dense 2-D network featuring zinc in both octahedral and tetrahedral coordination environments connected by trans-stilbene links. Similar reaction in diethylformamide (DEF) at higher temperatures resulted in a porous, 3-D framework structure consisting of two interpenetrating cubic lattices, each featuring basic to zinc carboxylate vertices joined by trans-stilbene, analogous to the isoreticular MOF (IRMOF) series. We demonstrate that the optical properties of both embodiments correlate directly with the local ligand environments observed in the crystal structures. We further demonstrate that these materials produce high luminescent response to proton radiation and high radiation tolerance relative to prior scintillators. These features can be used to create sophisticated scintillating detection sensors.

  2. Study of microstructure and semiconductor to metallic conductivity transition in solid state sintered Li{sub 0.5}Mn{sub 0.5}Fe{sub 2}O{sub 4??} spinel ferrite

    SciTech Connect (OSTI)

    Bhowmik, R. N., E-mail: rnbhowmik.phy@pondiuni.edu.in; Vijayasri, G. [Department of Physics, Pondicherry University, R. Venkataraman Nagar, Kalapet, Puducherry-605 014 (India)

    2013-12-14T23:59:59.000Z

    Li{sub 0.5}Mn{sub 0.5}Fe{sub 2}O{sub 4} ferrite has been prepared by solid state sintering route. XRD pattern showed single phased cubic spinel structure. The samples exhibited typical character of plastoferrite with ring shaped surface microstructure. New feature observed in the present ferrite is the frequency activated conductivity transition from semiconductor to metallic state above 800?K. The increase of conductivity with frequency in the semiconducting regime follows Jonscher power law, while decrease of conductivity in metallic regime obeys Drude equation. The conductivity in semiconductor regime has been understood by hopping mechanism of localized charge carriers among the cations in B sites of cubic spinel structure. At higher temperatures, overlapping of electronic orbitals from neighbouring ions and free particle like motion of lighter Li{sup +} ions among interstitial lattices contributed metallic conductivity. The samples provided evidence of localized nature of the charge carriers at lower temperatures and increasing delocalized character with the increase of measurement temperature. From application point of view, such ferrites behave as semiconductor at low temperature and allow electromagnetic wave to pass through, but transform into a metallic reflector with negative dielectric constant at high temperature.

  3. CFD MODELING AND SIMULATION IN MATERIALS PROCESSES Edited by TMS (The Minerals, Metals & Materials Society), 2004

    E-Print Network [OSTI]

    Zabaras, Nicholas J.

    Society), 2004 Solidification and Macrosegregation in Aluminum Alloys on Uneven Surfaces Deep Samanta1 school of Mechanical and Aerospace Engineering, Cornell University; Ithaca, NY 14853-3801, USA Keywords of metal aluminum and aluminum alloys is modeled on uneven surfaces char- acterized by sinusoidal curves

  4. Lattice mismatched compound semiconductors and devices on silicon

    E-Print Network [OSTI]

    Yang, Li, Ph. D. Massachusetts Institute of Technology

    2011-01-01T23:59:59.000Z

    III-V compound semiconductors, due to their superior electron mobility, are promising candidates for n-type metal-oxide-semiconductor field effect transistors (MOSFETs). However, the limited size of III-V substrates and ...

  5. New Conducting and Electrically Switching Molecular Materials based on Main Group and Transition Metal Ions Bridged by TCNQ Derivatives

    E-Print Network [OSTI]

    Zhang, Zhongyue

    2013-05-24T23:59:59.000Z

    ,7,8,8-tetracyanoquinodimethane) has played a central role in the design of many unprecedented conducting materials including the first purely organic conductor (TTF)(TCNQ) (TTF = tetrathiafulvalene) which is nearly metallic and the electrically bistable switching material Cu...

  6. Hydrogen storage material and process using graphite additive with metal-doped complex hydrides

    DOE Patents [OSTI]

    Zidan, Ragaiy (Aiken, SC); Ritter, James A. (Lexington, SC); Ebner, Armin D. (Lexington, SC); Wang, Jun (Columbia, SC); Holland, Charles E. (Cayce, SC)

    2008-06-10T23:59:59.000Z

    A hydrogen storage material having improved hydrogen absorbtion and desorption kinetics is provided by adding graphite to a complex hydride such as a metal-doped alanate, i.e., NaAlH.sub.4. The incorporation of graphite into the complex hydride significantly enhances the rate of hydrogen absorbtion and desorption and lowers the desorption temperature needed to release stored hydrogen.

  7. Solidification of Aluminum Alloys Edited by TMS (The Minerals, Metals & Materials Society), 2004

    E-Print Network [OSTI]

    Zabaras, Nicholas J.

    Solidification of Aluminum Alloys Edited by TMS (The Minerals, Metals & Materials Society), 2004 Modeling the Effects of Mold Topography on Aluminum Cast Surfaces Lijian Tan1 , Nicholas Zabaras1 1 14853, USA Keywords: Aluminum Solidification; Mold topography; Cast Surfaces Abstract The air

  8. SUPPORTING INFORMATION Comparison of non-precious metal cathode materials for methane

    E-Print Network [OSTI]

    S1 SUPPORTING INFORMATION Comparison of non-precious metal cathode materials for methane production H2SO4, and again in de-ionized water. Butyl rubber stoppers were used to prevent loss of gas from thick and 43 mm diameter) were cut from large butyl rubber sheets (McMaster-Carr, Cleveland, OH, USA

  9. Monomer-Capped Tin Metal Nanoparticles for Anode Materials in Lithium Secondary Batteries

    E-Print Network [OSTI]

    Cho, Jaephil

    Monomer-Capped Tin Metal Nanoparticles for Anode Materials in Lithium Secondary Batteries Mijung Graphite can store 372 mAh/g corresponding to LiC6, and tin can store 970 mAh/g corresponding to Li4.4Sn close to graphite. The reason for failure is believed to be the inhomogeneous volume expansion

  10. Removal and recovery of radionuclides and toxic metals from wastes, soils and materials

    SciTech Connect (OSTI)

    Francis, A.J.

    1993-07-01T23:59:59.000Z

    A process has been developed at Brookhaven National Laboratory (BNL) for the removal of metals and radionuclides from contaminated materials, soils, and waste sites (Figure 1). In this process, citric acid, a naturally occurring organic complexing agent, is used to extract metals such as Ba, Cd, Cr, Ni, Zn, and radionuclides Co, Sr, Th, and U from solid wastes by formation of water soluble, metal-citrate complexes. Citric acid forms different types of complexes with the transition metals and actinides, and may involve formation of a bidentate, tridentate, binuclear, or polynuclear complex species. The extract containing radionuclide/metal complex is then subjected to microbiological degradation followed by photochemical degradation under aerobic conditions. Several metal citrate complexes are biodegraded and the metals are recovered in a concentrated form with the bacterial biomass. Uranium forms binuclear complex with citric acid and is not biodegraded. The supernatant containing uranium citrate complex is separated and upon exposure to light, undergoes rapid degradation resulting in the formation of an insoluble, stable polymeric form of uranium. Uranium is recovered as a precipitate (uranium trioxide) in a concentrated form for recycling or for appropriate disposal. This treatment process, unlike others which use caustic reagents, does not create additional hazardous wastes for disposal and causes little damage to soil which can then be returned to normal use.

  11. Liquefaction process for solid carbonaceous materials containing alkaline earth metal humates

    DOE Patents [OSTI]

    Epperly, William R. (Summit, NJ); Deane, Barry C. (East Brunswick, NJ); Brunson, Roy J. (Buffalo Grove, IL)

    1982-01-01T23:59:59.000Z

    An improved liquefaction process wherein wall scale and particulate agglomeration during the liquefaction of solid carbonaceous materials containing alkaline earth metal humates is reduced and/or eliminated by subjecting the solid carbonaceous materials to controlled cyclic cavitation during liquefaction. It is important that the solid carbonaceous material be slurried in a suitable solvent or diluent during liquefaction. The cyclic cavitation may be imparted via pressure cycling, cyclic agitation and the like. When pressure cycling or the like is employed an amplitude equivalent to at least 25 psia is required to effectively remove scale from the liquefaction vessel walls.

  12. Adsorption and Diffusion of Hydrogen in a New Metal-Organic Framework Material: [Zn(bdc)(ted)0.5

    E-Print Network [OSTI]

    Li, Jing

    Adsorption and Diffusion of Hydrogen in a New Metal-Organic Framework Material: [Zn(bdc)(ted)0.5 pressure of 50 bar in a recently developed metal-organic framework material, [Zn(bdc)(ted)0.5] (bdc equilibrium molecular dynamics to compute self- and transport diffusivities of hydrogen in [Zn(bdc)(ted)0.5

  13. Solid-phase materials for chelating metal ions and methods of making and using same

    DOE Patents [OSTI]

    Harrup, Mason K.; Wey, John E.; Peterson, Eric S.

    2003-06-10T23:59:59.000Z

    A solid material for recovering metal ions from aqueous streams, and methods of making and using the solid material, are disclosed. The solid material is made by covalently bonding a chelating agent to a silica-based solid, or in-situ condensing ceramic precursors along with the chelating agent to accomplish the covalent bonding. The chelating agent preferably comprises a oxime type chelating head, preferably a salicylaldoxime-type molecule, with an organic tail covalently bonded to the head. The hydrocarbon tail includes a carbon-carbon double bond, which is instrumental in the step of covalently bonding the tail to the silica-based solid or the in-situ condensation. The invented solid material may be contacted directly with aqueous streams containing metal ions, and is selective to ions such as copper (II) even in the presence of such ions as iron (III) and other materials that are present in earthen materials. The solid material with high selectivity to copper may be used to recover copper from mining and plating industry streams, to replace the costly and toxic solvent extraction steps of conventional copper processing.

  14. Characterization of device parameters in high-temperature metal-oxide-semiconductor field-effect transistors in. beta. -SiC thin films

    SciTech Connect (OSTI)

    Palmour, J.W.; Kong, H.S.; Davis, R.F.

    1988-08-15T23:59:59.000Z

    Both inversion- and depletion-mode n-channel metal-oxide-semiconductor field-effect transistors (MOSFETs) have been fabricated on ..beta..-SiC thin films grown by chemical-vapor deposition. The inversion-mode devices were made on in situ doped (Al) p-type ..beta..-SiC(100) thin films grown on Si(100) substrates. The depletion-mode MOSFETs were made on n-type ..beta..-SiC(111) thin films grown on the Si(0001) face of a 6H ..cap alpha..-SiC substrates. Stable saturation and low subthreshold currents were achieved at drain-source voltages exceeding 5 and 25 V for the inversion-mode and depletion-mode devices, respectively. The transconductance increased with temperature up to 673 K for the short-gate-length devices, of either mode, and then decreased with further increases in temperature. It is proposed that the transconductances and threshold voltages for the inversion-mode devices are greatly affected by minority-carrier injection from the source. Stable transistor action was observed for both types of devices at temperatures up to 823 K, with the depletion-mode devices operating very well up to 923 K.

  15. Physical understanding of electron mobility in asymmetrically strained InGaAs-on-insulator metal-oxide-semiconductor field-effect transistors fabricated by lateral strain relaxation

    SciTech Connect (OSTI)

    Kim, SangHyeon, E-mail: dadembyora@mosfet.t.u-tokyo.ac.jp, E-mail: sh-kim@kist.re.kr; Yokoyama, Masafumi; Ikku, Yuki; Nakane, Ryosho; Takenaka, Mitsuru; Takagi, Shinichi [Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Ichikawa, Osamu; Osada, Takenori; Hata, Masahiko [Sumitomo Chemical Co. Ltd., 6 Kitahara, Tsukuba, Ibaraki 300-3294 (Japan)

    2014-03-17T23:59:59.000Z

    In this paper, we fabricated asymmetrically tensile-strained In{sub 0.53}Ga{sub 0.47}As-on-insulator (-OI) metal-oxide-semiconductor field-effect transistors (MOSFETs) using a lateral strain relaxation technique. A stripe-like line structure, fabricated in biaxially strained In{sub 0.53}Ga{sub 0.47}As-OI can lead to the lateral strain relaxation and asymmetric strain configuration in In{sub 0.53}Ga{sub 0.47}As-OI with the channel width of 100?nm. We have found that the effective mobility (?{sub eff}) enhancement in In{sub 0.53}Ga{sub 0.47}As-OI MOSFETs with uniaxial-like asymmetric strain becomes smaller than that in In{sub 0.53}Ga{sub 0.47}As-OI MOSFETs with biaxial strain. We have clarified from a systematic analysis between the strain values and the ?{sub eff} characteristics that this mobility behavior can be understood by the change of the energy level of the conduction band minimum due to the lateral strain relaxation.

  16. A microstructural approach toward the effect of thickness on semiconductor-to-metal transition characteristics of VO{sub 2} epilayers

    SciTech Connect (OSTI)

    Molaei, R., E-mail: rmolaei@ncsu.edu; Wu, F.; Narayan, J. [Department of Materials Science and Engineering, North Carolina State University, EB-1, Raleigh, North Carolina 27695-7907 (United States); Bayati, R. [Intel Corporation, IMO-SC, SC2, Santa Clara, California 95054 (United States)

    2014-04-28T23:59:59.000Z

    We report the control of semiconductor to metal transition in VO{sub 2}(010) epilayers integrated with Si(100) substrates buffered with an NiO[111]/YSZ[100] intermediate layer. VO{sub 2} epitaxial thin films were grown at different thicknesses varying from 10 to 200?nm using pulsed laser deposition technique. An epitaxial relationship of VO{sub 2}(010)?NiO(111)? YSZ(001)?Si(001) and VO{sub 2}[100]?NiO[110]? YSZ[100]?Si[100] was established at room temperature. The crystallographic alignment across the VO{sub 2}/NiO interface changes to VO{sub 2}(100)?NiO(111) and VO{sub 2}[001]?NiO[110] at the temperature of growth giving rise to a misfit strain of about 33.5% and 3.0% along two orthogonal in-plane orientations. The transition temperature was observed to vary from about 353 to 341?K, the transition amplitude increased by about five orders of magnitude, and the hysteresis decreased to about 3?K, as the thickness of VO{sub 2} layers increased from about 10 to 200?nm. These observations were explained based on strain characteristics, overall defect content and grain boundaries, and phenomenological thermodynamic models.

  17. Positive bias temperature instability in p-type metal-oxide-semiconductor devices with HfSiON/SiO{sub 2} gate dielectrics

    SciTech Connect (OSTI)

    Samanta, Piyas, E-mail: piyas@vcfw.org [Department of Physics, Vidyasagar College for Women, 39 Sankar Ghosh Lane, Kolkata 700 006 (India); Huang, Heng-Sheng; Chen, Shuang-Yuan [Institute of Mechatronic Engineering, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Rd., Taipei 106, Taiwan (China); Liu, Chuan-Hsi [Department of Mechatronic Technology, National Taiwan Normal University, No. 162, Sec. 1, He-Ping E. Rd., Taipei 106, Taiwan (China); Cheng, Li-Wei [Central R and D Division, United Microelectronics Corporation, No. 3, Li-Hsin Rd. II, Hsinchu 300, Taiwan (China)

    2014-02-21T23:59:59.000Z

    We present a detailed investigation on positive-bias temperature stress (PBTS) induced degradation of nitrided hafnium silicate (HfSiON)/SiO{sub 2} gate stack in n{sup +}-poly crystalline silicon (polySi) gate p-type metal-oxide-semiconductor (pMOS) devices. The measurement results indicate that gate dielectric degradation is a composite effect of electron trapping in as-fabricated as well as newly generated neutral traps, resulting a significant amount of stress-induced leakage current and generation of surface states at the Si/SiO{sub 2} interface. Although, a significant amount of interface states are created during PBTS, the threshold voltage (V{sub T}) instability of the HfSiON based pMOS devices is primarily caused by electron trapping and detrapping. It is also shown that PBTS creates both acceptor- and donor-like interface traps via different depassivation mechanisms of the Si{sub 3}???SiH bonds at the Si/SiO{sub 2} interface in pMOS devices. However, the number of donor-like interface traps ?N{sub it}{sup D} is significantly greater than that of acceptor-like interface traps ?N{sup A}{sub it}, resulting the PBTS induced net interface traps as donor-like.

  18. Thin film three-dimensional topological insulator metal-oxide-semiconductor field-effect-transistors: A candidate for sub-10?nm devices

    SciTech Connect (OSTI)

    Akhavan, N. D., E-mail: nima.dehdashti@uwa.edu.au; Jolley, G.; Umana-Membreno, G. A.; Antoszewski, J.; Faraone, L. [Department of Electrical, Electronic and Computer Engineering, University of Western Australia, Crawley, WA 6009 (Australia)

    2014-08-28T23:59:59.000Z

    Three-dimensional (3D) topological insulators (TI) are a new state of quantum matter in which surface states reside in the bulk insulating energy bandgap and are protected by time-reversal symmetry. It is possible to create an energy bandgap as a consequence of the interaction between the conduction band and valence band surface states from the opposite surfaces of a TI thin film, and the width of the bandgap can be controlled by the thin film thickness. The formation of an energy bandgap raises the possibility of thin-film TI-based metal-oxide-semiconductor field-effect-transistors (MOSFETs). In this paper, we explore the performance of MOSFETs based on thin film 3D-TI structures by employing quantum ballistic transport simulations using the effective continuous Hamiltonian with fitting parameters extracted from ab-initio calculations. We demonstrate that thin film transistors based on a 3D-TI structure provide similar electrical characteristics compared to a Si-MOSFET for gate lengths down to 10?nm. Thus, such a device can be a potential candidate to replace Si-based MOSFETs in the sub-10?nm regime.

  19. Analysis of AlN/AlGaN/GaN metal-insulator-semiconductor structure by using capacitance-frequency-temperature mapping

    SciTech Connect (OSTI)

    Shih, Hong-An; Kudo, Masahiro; Suzuki, Toshi-kazu [Center for Nano Materials and Technology, Japan Advanced Institute of Science and Technology (JAIST), 1-1 Asahidai, Nomi, Ishikawa 923-1292 (Japan)

    2012-07-23T23:59:59.000Z

    AlN/AlGaN/GaN metal-insulator-semiconductor (MIS) structure is analyzed by using capacitance-frequency-temperature (C-f-T) mapping. Applying sputtering-deposited AlN, we attained AlN/AlGaN/GaN MIS heterostructure field-effect transistors with much suppressed gate leakage currents, but exhibiting frequency dispersion in C-V characteristics owing to high-density AlN/AlGaN interface states. In order to investigate the interface states deteriorating the device performance, we measured temperature-dependent frequency dispersion in the C-V characteristics. As a result, we obtained C-f-T mapping, whose analysis gives the activation energies of electron trapping, namely the interface state energy levels, for a wide range of the gate biases. This analysis method is auxiliary to the conventional conductance method, serving as a valuable tool for characterization of wide-bandgap devices with deep interface states. From the analysis, we can directly evaluate the gate-control efficiency of the devices.

  20. Low-frequency noise in AlN/AlGaN/GaN metal-insulator-semiconductor devices: A comparison with Schottky devices

    SciTech Connect (OSTI)

    Le, Son Phuong; Nguyen, Tuan Quy; Shih, Hong-An; Kudo, Masahiro; Suzuki, Toshi-kazu, E-mail: tosikazu@jaist.ac.jp [Center for Nano Materials and Technology, Japan Advanced Institute of Science and Technology (JAIST), 1-1 Asahidai, Nomi, Ishikawa 923-1292 (Japan)

    2014-08-07T23:59:59.000Z

    We have systematically investigated low-frequency noise (LFN) in AlN/AlGaN/GaN metal-insulator-semiconductor (MIS) devices, where the AlN gate insulator layer was sputtering-deposited on the AlGaN surface, in comparison with LFN in AlGaN/GaN Schottky devices. By measuring LFN in ungated two-terminal devices and heterojunction field-effect transistors (HFETs), we extracted LFN characteristics in the intrinsic gated region of the HFETs. Although there is a bias regime of the Schottky-HFETs in which LFN is dominated by the gate leakage current, LFN in the MIS-HFETs is always dominated by only the channel current. Analyzing the channel-current-dominated LFN, we obtained Hooge parameters ? for the gated region as a function of the sheet electron concentration n{sub s} under the gate. In a regime of small n{sub s}, both the MIS- and Schottky-HFETs exhibit ??n{sub s}{sup ?1}. On the other hand, in a middle n{sub s} regime of the MIS-HFETs, ? decreases rapidly like n{sub s}{sup ??} with ????2-3, which is not observed for the Schottky-HFETs. In addition, we observe strong increase in ??n{sub s}{sup 3} in a large n{sub s} regime for both the MIS- and Schottky-HFETs.

  1. SEQUESTRATION OF METALS IN ACTIVE CAP MATERIALS: A LABORATORY AND NUMERICAL EVALUATION

    SciTech Connect (OSTI)

    Dixon, K.; Knox, A.

    2012-02-13T23:59:59.000Z

    Active capping involves the use of capping materials that react with sediment contaminants to reduce their toxicity or bioavailability. Although several amendments have been proposed for use in active capping systems, little is known about their long-term ability to sequester metals. Recent research has shown that the active amendment apatite has potential application for metals contaminated sediments. The focus of this study was to evaluate the effectiveness of apatite in the sequestration of metal contaminants through the use of short-term laboratory column studies in conjunction with predictive, numerical modeling. A breakthrough column study was conducted using North Carolina apatite as the active amendment. Under saturated conditions, a spike solution containing elemental As, Cd, Co, Se, Pb, Zn, and a non-reactive tracer was injected into the column. A sand column was tested under similar conditions as a control. Effluent water samples were periodically collected from each column for chemical analysis. Relative to the non-reactive tracer, the breakthrough of each metal was substantially delayed by the apatite. Furthermore, breakthrough of each metal was substantially delayed by the apatite compared to the sand column. Finally, a simple 1-D, numerical model was created to qualitatively predict the long-term performance of apatite based on the findings from the column study. The results of the modeling showed that apatite could delay the breakthrough of some metals for hundreds of years under typical groundwater flow velocities.

  2. Searching Room Temperature Ferromagnetism in Wide Gap Semiconductors Fe-doped Strontium Titanate and Zinc Oxide

    E-Print Network [OSTI]

    Pereira, LMC; Wahl, U

    Scientic findings in the very beginning of the millennium are taking us a step further in the new paradigm of technology: spintronics. Upgrading charge-based electronics with the additional degree of freedom of the carriers spin-state, spintronics opens a path to the birth of a new generation of devices with the potential advantages of non-volatility and higher processing speed, integration densities and power efficiency. A decisive step towards this new age lies on the attribution of magnetic properties to semiconductors, the building block of today's electronics, that is, the realization of ferromagnetic semiconductors (FS) with critical temperatures above room temperature. Unfruitful search for intrinsic RT FS lead to the concept of Dilute(d) Magnetic Semiconductors (DMS): ordinary semiconductor materials where 3 d transition metals randomly substitute a few percent of the matrix cations and, by some long-range mechanism, order ferromagnetically. The times are of intense research activity and the last few ...

  3. Electrospun and oxidized cellulose materials for environmental remediation of heavy metals in groundwater

    SciTech Connect (OSTI)

    Han, Dong [Stony Brook University (SUNY); Halada, Gary P. [Stony Brook University (SUNY); Spalding, Brian Patrick [ORNL; Brooks, Scott C [ORNL

    2009-12-01T23:59:59.000Z

    This chapter focuses on the use of modified cellulosic materials in the field of environmental remediation. Two different chemical methods were involved in fabricating oxidized cellulose (OC), which has shown promise as a metal ion chelator in environmental applications. Electrospinning was utilized to introduce a more porous structure into an oxidized cellulose matrix. FTIR and Raman spectroscopy were used to study both the formation of OC and its surface complexation with metal ions. IR and Raman spectroscopic data demonstrate the formation of characteristic carboxylic groups in the structure of the final products and the successful formation of OC-metal complexes. Subsequent field tests at the Field Research Site at Oak Ridge National Laboratory confirmed the value of OC for sorption of both U and Th ions.

  4. The interfacial chemistry of solidification/stabilization of metals in cement and pozzolanic material systems

    SciTech Connect (OSTI)

    Yousuf, M.; Mollah, A.; Vempati, R.K.; Lin, T.C.; Cocke, D.L. [Lamar Univ., Beaumont, TX (United States)] [Lamar Univ., Beaumont, TX (United States)

    1995-11-01T23:59:59.000Z

    The chemistry of cement, its hydration and mechanisms of solidification/stabilization (s/s) of toxic metals by cement-based systems and pozzolanic materials are significantly controlled by surface, near-surface and interfacial phenomena. The adsorption conditions and the selectivity strong affinity of hazardous metals towards clay minerals, certain hydrated metal oxides and oxyhydroxides, and cementitous substances also play an important role in the s/s process for the immobilization of contaminants. Recent works from the authors` laboratory involving metal ions and superplasticizers have elucidated the mechanisms of reactions leading to the retardation of cement hydration and subsequent setting and their interactions with silicate-based systems. This article delineates the current status of interfacial chemistry at the solid-liquid boundary and places it in perspective with present and future s/s processes based on Portland cement and pozzolanic materials. The importance of surface charge, the role of interfacial phenomena on adsorption, and the importance of calcium and other types of anions and cations in s/s are also discussed. A surface charge control reaction model that accounts for the importance of calcium and other cations and anions is outlined and used to discuss the chemical nature and microstructure of the interfacial transition zone.

  5. SEMICONDUCTOR DETECTORS - AN INTRODUCTION

    E-Print Network [OSTI]

    Goulding, F.S.

    2011-01-01T23:59:59.000Z

    infrinfc primely owned dtfiw. SEMICONDUCTOR DETECTORS - ANi) LBL-7282 I. History Semiconductor detectors appeared onof alpha particles by semiconductor diodes several years

  6. Isotopically controlled semiconductors

    E-Print Network [OSTI]

    Haller, E.E.

    2004-01-01T23:59:59.000Z

    and phonons in semiconductors,” J. Non-Cryst. Solids 141 (LVM) Spectroscopy of Semiconductors,” Mat. Res. Soc. Symp.Isotopically Engineered Semiconductors – New Media for the

  7. Semiconductor Nanowires: What's Next?

    E-Print Network [OSTI]

    Yang, Peidong

    2011-01-01T23:59:59.000Z

    Semiconductor nanowires, what’s next? Peidong Yang, Ruoxuelater research into semiconductor whiskers with nanoscalewere popularized as semiconductor nanowires in the following

  8. Energetics of Electron Transfer at the Nanocrystalline Titanium Dioxide Semiconductor/ Aqueous Solution Interface: pH Invariance of the Metal-Based Formal Potential of a

    E-Print Network [OSTI]

    Energetics of Electron Transfer at the Nanocrystalline Titanium Dioxide Semiconductor/ Aqueous,4-(CH2PO3)-2,2-bipyridine)3 10-, bound to a nanocrystalline titanium dioxide film shows energy (ECB) of the underlying semiconductor electrode in response to the same environmental

  9. Hydridable material for the negative electrode in a nickel-metal hydride storage battery

    DOE Patents [OSTI]

    Knosp, Bernard (Neuilly-sur-Seine, FR); Bouet, Jacques (Paris, FR); Jordy, Christian (Dourdan, FR); Mimoun, Michel (Neuilly-sur-Marne, FR); Gicquel, Daniel (Lanorville, FR)

    1997-01-01T23:59:59.000Z

    A monophase hydridable material for the negative electrode of a nickel-metal hydride storage battery with a "Lave's phase" structure of hexagonal C14 type (MgZn.sub.2) has the general formula: Zr.sub.1-x Ti.sub.x Ni.sub.a Mn.sub.b Al.sub.c Co.sub.d V.sub.e where ##EQU1##

  10. Yucca Mountain project canister material corrosion studies as applied to the electrometallurgical treatment metallic waste form

    SciTech Connect (OSTI)

    Keiser, D.D.

    1996-11-01T23:59:59.000Z

    Yucca Mountain, Nevada is currently being evaluated as a potential site for a geologic repository. As part of the repository assessment activities, candidate materials are being tested for possible use as construction materials for waste package containers. A large portion of this testing effort is focused on determining the long range corrosion properties, in a Yucca Mountain environment, for those materials being considered. Along similar lines, Argonne National Laboratory is testing a metallic alloy waste form that also is scheduled for disposal in a geologic repository, like Yucca Mountain. Due to the fact that Argonne`s waste form will require performance testing for an environment similar to what Yucca Mountain canister materials will require, this report was constructed to focus on the types of tests that have been conducted on candidate Yucca Mountain canister materials along with some of the results from these tests. Additionally, this report will discuss testing of Argonne`s metal waste form in light of the Yucca Mountain activities.

  11. LENS repair and modification of metal NW components:materials and applications guide.

    SciTech Connect (OSTI)

    Smugeresky, John E. (Sandia National Laboratories, Livermore, CA); Gill, David Dennis; Oberhaus, Jason (BWXT Y-12); Adams, Thad (Savannah River National Laboratory); VanCamp, Chad (Kansas City Plant)

    2006-11-01T23:59:59.000Z

    Laser Engineered Net Shaping{trademark} (LENS{reg_sign}) is a unique, layer additive, metal manufacturing technique that offers the ability to create fully dense metal features and components directly from a computer solid model. LENS offers opportunities to repair and modify components by adding features to existing geometry, refilling holes, repairing weld lips, and many other potential applications. The material deposited has good mechanical properties with strengths typically slightly higher that wrought material due to grain refinement from a quickly cooling weld pool. The result is a material with properties similar to cold worked material, but without the loss in ductility traditionally seen with such treatments. Furthermore, 304L LENS material exhibits good corrosion resistance and hydrogen compatibility. This report gives a background of the LENS process including materials analysis addressing the requirements of a number of different applications. Suggestions are given to aid both the product engineer and the process engineer in the successful utilization of LENS for their applications. The results of testing on interface strength, machinability, weldability, corrosion resistance, geometric effects, heat treatment, and repair strategy testing are all included. Finally, the qualification of the LENS process is briefly discussed to give the user confidence in selecting LENS as the process of choice for high rigor applications. The testing showed LENS components to have capability in repair/modification applications requiring complex castings (W80-3 D-Bottle bracket), thin wall parts requiring metal to be rebuilt onto the part (W87 Firing Set Housing and Y-12 Test Rings), the filling of counterbores for use in reservoir reclamation welding (SRNL hydrogen compatibility study) and the repair of surface defects on pressure vessels (SRNL gas bottle repair). The material is machinable, as testing has shown that LENS deposited material machines similar to that of welded metal. Tool wear is slightly higher in LENS material than in wrought material, but not so much that one would be concerned with increased tooling cost. The LENS process achieved process qualification for the AY1E0125 D-Bottle Bracket from the W80-3 LEP program, and in the effort, also underwent testing in weapons environments. These tests included structural dynamic response testing and drop testing. The LENS deposited parts were compared in these tests with conventionally machined parts and showed equivalency to such an extent that the parts were accepted for use in parallel path subsystem-level weapon environment testing. The evaluation of LENS has shown that the process can be a viable option when either complete metal parts are needed or existing metal parts require modification or repair. The LENS Qualification Technology Investment team successfully investigated new applications for the LENS process and showed that it has great applicability across the Nuclear Weapons Complex as well as in other high rigor applications.

  12. A methodology to identify and quantify mobility-reducing defects in 4H-silicon carbide power metal-oxide-semiconductor field-effect transistors

    SciTech Connect (OSTI)

    Ettisserry, D. P., E-mail: deva@umd.edu; Goldsman, N. [Department of Electrical and Computer Engineering, University of Maryland, College Park, Maryland 20742 (United States); Lelis, A. [U.S. Army Research Laboratory, 2800 Powder Mill Road, Adelphi, Maryland 20783 (United States)

    2014-03-14T23:59:59.000Z

    In this paper, we present a methodology for the identification and quantification of defects responsible for low channel mobility in 4H-Silicon Carbide (SiC) power metal-oxide-semiconductor field-effect transistors (MOSFETs). To achieve this, we use an algorithm based on 2D-device simulations of a power MOSFET, density functional simulations, and measurement data. Using physical modeling of carrier mobility and interface traps, we reproduce the experimental I-V characteristics of a 4H-SiC doubly implanted MOSFET through drift-diffusion simulation. We extract the position of Fermi level and the occupied trap density as a function of applied bias and temperature. Using these inputs, our algorithm estimates the number of possible trap types, their energy levels, and concentrations at 4H-SiC/SiO{sub 2} interface. Subsequently, we use density functional theory (DFT)-based ab initio simulations to identify the atomic make-up of defects causing these trap levels. We study silicon vacancy and carbon di-interstitial defects in the SiC side of the interface. Our algorithm indicates that the D{sub it} spectrum near the conduction band edge (3.25?eV) is composed of three trap types located at 2.8–2.85?eV, 3.05?eV, and 3.1–3.2?eV, and also calculates their densities. Based on DFT simulations, this work attributes the trap levels very close to the conduction band edge to the C di-interstitial defect.

  13. Sample size requirements for estimating effective dose from computed tomography using solid-state metal-oxide-semiconductor field-effect transistor dosimetry

    SciTech Connect (OSTI)

    Trattner, Sigal [Department of Medicine, Division of Cardiology, Columbia University Medical Center and New York-Presbyterian Hospital, New York, New York 10032 (United States)] [Department of Medicine, Division of Cardiology, Columbia University Medical Center and New York-Presbyterian Hospital, New York, New York 10032 (United States); Cheng, Bin [Department of Biostatistics, Columbia University Mailman School of Public Health, New York, New York 10032 (United States)] [Department of Biostatistics, Columbia University Mailman School of Public Health, New York, New York 10032 (United States); Pieniazek, Radoslaw L. [Center for Radiological Research, Columbia University Medical Center and New York-Presbyterian Hospital, New York, New York 10032 (United States)] [Center for Radiological Research, Columbia University Medical Center and New York-Presbyterian Hospital, New York, New York 10032 (United States); Hoffmann, Udo [Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114 (United States)] [Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114 (United States); Douglas, Pamela S. [Department of Medicine, Division of Cardiology, Duke University, Durham, North Carolina 27715 (United States)] [Department of Medicine, Division of Cardiology, Duke University, Durham, North Carolina 27715 (United States); Einstein, Andrew J., E-mail: andrew.einstein@columbia.edu [Department of Medicine, Division of Cardiology, Columbia University Medical Center and New York-Presbyterian Hospital, New York, New York and Department of Radiology, Columbia University Medical Center and New York-Presbyterian Hospital, New York, New York (United States)

    2014-04-15T23:59:59.000Z

    Purpose: Effective dose (ED) is a widely used metric for comparing ionizing radiation burden between different imaging modalities, scanners, and scan protocols. In computed tomography (CT), ED can be estimated by performing scans on an anthropomorphic phantom in which metal-oxide-semiconductor field-effect transistor (MOSFET) solid-state dosimeters have been placed to enable organ dose measurements. Here a statistical framework is established to determine the sample size (number of scans) needed for estimating ED to a desired precision and confidence, for a particular scanner and scan protocol, subject to practical limitations. Methods: The statistical scheme involves solving equations which minimize the sample size required for estimating ED to desired precision and confidence. It is subject to a constrained variation of the estimated ED and solved using the Lagrange multiplier method. The scheme incorporates measurement variation introduced both by MOSFET calibration, and by variation in MOSFET readings between repeated CT scans. Sample size requirements are illustrated on cardiac, chest, and abdomen–pelvis CT scans performed on a 320-row scanner and chest CT performed on a 16-row scanner. Results: Sample sizes for estimating ED vary considerably between scanners and protocols. Sample size increases as the required precision or confidence is higher and also as the anticipated ED is lower. For example, for a helical chest protocol, for 95% confidence and 5% precision for the ED, 30 measurements are required on the 320-row scanner and 11 on the 16-row scanner when the anticipated ED is 4 mSv; these sample sizes are 5 and 2, respectively, when the anticipated ED is 10 mSv. Conclusions: Applying the suggested scheme, it was found that even at modest sample sizes, it is feasible to estimate ED with high precision and a high degree of confidence. As CT technology develops enabling ED to be lowered, more MOSFET measurements are needed to estimate ED with the same precision and confidence.

  14. Materials Down-selection Decisions Made within the DOE Metal Hydride Center of Excellence (MHCoE) - September-October 2007

    Fuel Cell Technologies Publication and Product Library (EERE)

    Reports on which hydrogen storage materials offer potential for further research as decided by DOE's Metal Hydride Center of Excellence.

  15. A biopolymer-like metal enabled hybrid material with exceptional mechanical prowess

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhang, Junsong; Cui, Lishan; Jiang, Daqiang; Liu, Yinong; Hao, Shijie; Ren, Yang; Han, Xiaodong; Liu, Zhenyang; Wang, Yunzhi; Yu, Cun; et al

    2015-02-10T23:59:59.000Z

    The design principles for naturally occurring biological materials have inspired us to develop next-generation engineering materials with remarkable performance. Nacre, commonly referred to as nature’s armor, is renowned for its unusual combination of strength and toughness. Nature’s wisdom in nacre resides in its elaborate structural design and the judicious placement of a unique organic biopolymer with intelligent deformation features. However, up to now, it is still a challenge to transcribe the biopolymer’s deformation attributes into a stronger substitute in the design of new materials. In this study, we propose a new design strategy that employs shape memory alloy to transcribemore »the ‘‘J-curve’’ mechanical response and uniform molecular/atomic level deformation of the organic biopolymer in the design of high-performance hybrid materials. This design strategy is verified in a TiNi-Ti3Sn model material system. The model material demonstrates an exceptional combination of mechanical properties that are superior to other high-performance metal-based lamellar composites known to date. Our design strategy creates new opportunities for the development of high-performance bio-inspired materials.« less

  16. Construction of a Deep Level Transient Spectroscopy (DLTS) Setup Semiconductors and DLTS

    E-Print Network [OSTI]

    Zhao, Yuxiao

    Construction of a Deep Level Transient Spectroscopy (DLTS) Setup Semiconductors and DLTS Semiconductor devices are central to information technology. Their importance stems from the fact Ian Booker Semiconductor Materials Group Dept. Of Physics, Chemistry and Biology, IFM Linköping

  17. Problems in the theory of thermal Casimir force between dielectrics and semiconductors

    E-Print Network [OSTI]

    G. L. Klimchitskaya; B. Geyer

    2008-02-26T23:59:59.000Z

    The application of the Lifshitz theory to describe the thermal Casimir force between dielectrics and semiconductors is considered. It is shown that for all true dielectrics (i.e., for all materials having zero conductivity at zero temperature) the inclusion of a nonzero conductivity arising at nonzero temperature into the model of dielectric response leads to the violation of the Nernst heat theorem. This result refers equally to simple insulators, intrinsic semiconductors, Mott-Hubbard dielectrics and doped semiconductors with doping concentration below a critical value. We demonstrate that in the insulator-metal transition the Casimir free energy changes abruptly irrespective of whether the conductivity changes continuously or discontinuously. The application of the Lifshitz formula to polar dielectrics results in large thermal correction that is linear in temperature. A rule is formulated on how to apply the Lifshitz theory to real materials in agreement with thermodynamics and experiment.

  18. Braze material for joining ceramic to metal and ceramic to ceramic surfaces and joined ceramic to metal and ceramic to ceramic article

    DOE Patents [OSTI]

    Hunt, Thomas K. (Ann Arbor, MI); Novak, Robert F. (Farmington Hills, MI)

    1991-01-01T23:59:59.000Z

    An improved active metal braze filler material is provided in which the coefficient of thermal expansion of the braze filler is more closely matched with that of the ceramic and metal, or two ceramics, to provide ceramic to metal, or ceramic to ceramic, sealed joints and articles which can withstand both high temperatures and repeated thermal cycling without failing. The braze filler material comprises a mixture of a material, preferably in the form of a powder, selected from the group consisting of molybdenum, tungsten, silicon carbide and mixtures thereof, and an active metal filler material selected from the group consisting of alloys or mixtures of nickel and titanium, alloys or mixtures of nickel and zirconium, alloys or mixtures of nickel, titanium, and copper, alloys or mixtures of nickel, titanium, and zirconium, alloys or mixtures of niobium and nickel, alloys or mixtures of niobium and zirconium, alloys or mixtures of niobium and titanium, alloys or mixtures of niobium, titanium, and nickel, alloys or mixtures of niobium, zirconium, and nickel, and alloys or mixtures of niobium, titanium, zirconium, and nickel. The powder component is selected such that its coefficient of thermal expansion will effect the overall coefficient of thermal expansion of the braze material so that it more closely matches the coefficients of thermal expansion of the ceramic and metal parts to be joined.

  19. Creating a Discovery Platform for Confined-Space Chemistry and Materials: Metal-Organic Frameworks.

    SciTech Connect (OSTI)

    Allendorf, Mark D.; Greathouse, Jeffery A. [Sandia National Laboratories, Albuquerque, NM; Simmons, Blake

    2008-09-01T23:59:59.000Z

    Metal organic frameworks (MOF) are a recently discovered class of nanoporous, defect-free crystalline materials that enable rational design and exploration of porous materials at the molecular level. MOFs have tunable monolithic pore sizes and cavity environments due to their crystalline nature, yielding properties exceeding those of most other porous materials. These include: the lowest known density (91% free space); highest surface area; tunable photoluminescence; selective molecular adsorption; and methane sorption rivaling gas cylinders. These properties are achieved by coupling inorganic metal complexes such as ZnO4 with tunable organic ligands that serve as struts, allowing facile manipulation of pore size and surface area through reactant selection. MOFs thus provide a discovery platform for generating both new understanding of chemistry in confined spaces and novel sensors and devices based on their unique properties. At the outset of this project in FY06, virtually nothing was known about how to couple MOFs to substrates and the science of MOF properties and how to tune them was in its infancy. An integrated approach was needed to establish the required knowledge base for nanoscale design and develop methodologies integrate MOFs with other materials. This report summarizes the key accomplishments of this project, which include creation of a new class of radiation detection materials based on MOFs, luminescent MOFs for chemical detection, use of MOFs as templates to create nanoparticles of hydrogen storage materials, MOF coatings for stress-based chemical detection using microcantilevers, and %22flexible%22 force fields that account for structural changes in MOFs that occur upon molecular adsorption/desorption. Eight journal articles, twenty presentations at scientific conferences, and two patent applications resulted from the work. The project created a basis for continuing development of MOFs for many Sandia applications and succeeded in securing %242.75 M in funding from outside agencies to continue the research. 3

  20. 1.0. Semiconductor Diodes 1 of 27 1.2 Ideal Diode

    E-Print Network [OSTI]

    Allen, Gale

    1.0. Semiconductor Diodes 1 of 27 1.2 Ideal Diode ID VD ID Open Circuit Short Circuit VD + - #12;1.0. Semiconductor Diodes 2 of 27 1.3 Semiconductor Materials Conductor Insulator Semiconductor R = (Resistivity Resistivity of a semiconductor decreases as temperature increases. ure coefficient.Negative temperat #12

  1. Composite materials with metal oxide attached to lead chalcogenide nanocrystal quantum dots with linkers

    DOE Patents [OSTI]

    Fuke, Nobuhiro; Koposov, Alexey Y; Sykora, Milan; Hoch, Laura

    2014-12-16T23:59:59.000Z

    Composite materials useful for devices such as photoelectrochemical solar cells include a substrate, a metal oxide film on the substrate, nanocrystalline quantum dots (NQDs) of lead sulfide, lead selenide, and lead telluride, and linkers that attach the NQDs to the metal oxide film. Suitable linkers preserve the 1s absorption peak of the NQDs. A suitable linker has a general structure A-B-C where A is a chemical group adapted for binding to a MO.sub.x and C is a chemical group adapted for binding to a NQD and B is a divalent, rigid, or semi-rigid organic spacer moiety. Other linkers that preserve the 1s absorption peak may also be used.

  2. Photodeposition of Pt on Colloidal CdS and CdSe/CdS Semiconductor Nanostructures

    SciTech Connect (OSTI)

    Dukovic, Gordana; Merkle, Maxwell G.; Nelson, James H.; Hughes, Steven M.; Alivisatos, A. Paul

    2008-08-06T23:59:59.000Z

    Semiconductor photocatalysis has been identified as a promising avenue for the conversion of solar energy into environmentally friendly fuels, most notably by the production of hydrogen from water.[1-5] Nanometer-scale materials in particular have attracted considerable scientific attention as the building blocks for light-harvesting applications.[6,7] Their desirable attributes include tunability of the optical properties with size, amenability to relatively inexpensive low-temperature processing, and a high degree of synthetic sophistication leading to increasingly complex and multi-functional architectures. For photocatalysis in particular, the high surface-to-volume ratios in nanoscale materials should lead to an increased availability of carriers for redox reactions on the nanoparticle surface. Recombination of photoexcited carriers directly competes with photocatalytic activity.[3] Charge separation is often achieved with multi-component heterostructures. An early example is the case of TiO2 powders functionalized with Pt and RuO2 particles, where photoexcited electrons are transferred to Pt (the reduction site) and holes to RuO2 (the oxidation site).[8] More recently, many colloidally synthesized nanometer-scale metal-semiconductor heterostructures have been reported.[7,9,10] A majority of these structures are made by thermal methods.[7,10] We have chosen to study photochemical formation of metal-semiconductor heterostructures. The detailed understanding of the mechanisms involved in photodeposition of metals on nanometer-scale semiconductors is necessary to enable a high degree of synthetic control. At the same time, because the results of metal deposition can be directly observed by electron microscopy, it can be used to understand how factors such as nanocrystal composition, shape, carrier dynamics, and surface chemistry influence the photochemical properties of semiconductor nanocrystals. In this communication, we report on the photodeposition of Pt on colloidal CdS and CdSe/CdS core/shell nanocrystals. Among the II-VI semiconductors, CdS is of particular interest because it has the correct band alignment for water photolysis[2] and has been demonstrated to be photocatalytically active.[11-16] We have found that the photoexcitation of CdS and CdSe/CdS in the presence of an organometallic Pt precursor leads to deposition of Pt nanoparticles on the semiconductor surface. Stark differences are observed in the Pt nanoparticle location on the two substrates, and the photodeposition can be completely inhibited by the modification of the semiconductor surface. Our results suggest that tuning of the semiconductor band structure, spatial organization and surface chemistry should be crucial in the design of photocatalytic nanostructures.

  3. Transmissive metallic contact for amorphous silicon solar cells

    DOE Patents [OSTI]

    Madan, A.

    1984-11-29T23:59:59.000Z

    A transmissive metallic contact for amorphous silicon semiconductors includes a thin layer of metal, such as aluminum or other low work function metal, coated on the amorphous silicon with an antireflective layer coated on the metal. A transparent substrate, such as glass, is positioned on the light reflective layer. The metallic layer is preferably thin enough to transmit at least 50% of light incident thereon, yet thick enough to conduct electricity. The antireflection layer is preferably a transparent material that has a refractive index in the range of 1.8 to 2.2 and is approximately 550A to 600A thick.

  4. Stable surface passivation process for compound semiconductors

    DOE Patents [OSTI]

    Ashby, Carol I. H. (Edgewood, NM)

    2001-01-01T23:59:59.000Z

    A passivation process for a previously sulfided, selenided or tellurated III-V compound semiconductor surface. The concentration of undesired mid-gap surface states on a compound semiconductor surface is reduced by the formation of a near-monolayer of metal-(sulfur and/or selenium and/or tellurium)-semiconductor that is effective for long term passivation of the underlying semiconductor surface. Starting with the III-V compound semiconductor surface, any oxidation present thereon is substantially removed and the surface is then treated with sulfur, selenium or tellurium to form a near-monolayer of chalcogen-semiconductor of the surface in an oxygen-free atmosphere. This chalcogenated surface is then contacted with a solution of a metal that will form a low solubility chalcogenide to form a near-monolayer of metal-chalcogen-semiconductor. The resulting passivating layer provides long term protection for the underlying surface at or above the level achieved by a freshly chalcogenated compound semiconductor surface in an oxygen free atmosphere.

  5. Back-side readout semiconductor photomultiplier

    DOE Patents [OSTI]

    Choong, Woon-Seng; Holland, Stephen E

    2014-05-20T23:59:59.000Z

    This disclosure provides systems, methods, and apparatus related to semiconductor photomultipliers. In one aspect, a device includes a p-type semiconductor substrate, the p-type semiconductor substrate having a first side and a second side, the first side of the p-type semiconductor substrate defining a recess, and the second side of the p-type semiconductor substrate being doped with n-type ions. A conductive material is disposed in the recess. A p-type epitaxial layer is disposed on the second side of the p-type semiconductor substrate. The p-type epitaxial layer includes a first region proximate the p-type semiconductor substrate, the first region being implanted with p-type ions at a higher doping level than the p-type epitaxial layer, and a second region disposed on the first region, the second region being doped with p-type ions at a higher doping level than the first region.

  6. Semiconductor switch geometry with electric field shaping

    DOE Patents [OSTI]

    Booth, Rex (Livermore, CA); Pocha, Michael D. (Livermore, CA)

    1994-01-01T23:59:59.000Z

    An optoelectric switch is disclosed that utilizes a cylindrically shaped and contoured GaAs medium or other optically active semiconductor medium to couple two cylindrically shaped metal conductors with flat and flared termination points each having an ovoid prominence centrally extending there from. Coupling the truncated ovoid prominence of each conductor with the cylindrically shaped optically active semiconductor causes the semiconductor to cylindrically taper to a triple junction circular line at the base of each prominence where the metal conductor conjoins with the semiconductor and a third medium such as epoxy or air. Tapering the semiconductor at the triple junction inhibits carrier formation and injection at the triple junction and thereby enables greater current carrying capacity through and greater sensitivity of the bulk area of the optically active medium.

  7. Semiconductor switch geometry with electric field shaping

    DOE Patents [OSTI]

    Booth, R.; Pocha, M.D.

    1994-08-23T23:59:59.000Z

    An optoelectric switch is disclosed that utilizes a cylindrically shaped and contoured GaAs medium or other optically active semiconductor medium to couple two cylindrically shaped metal conductors with flat and flared termination points each having an ovoid prominence centrally extending there from. Coupling the truncated ovoid prominence of each conductor with the cylindrically shaped optically active semiconductor causes the semiconductor to cylindrically taper to a triple junction circular line at the base of each prominence where the metal conductor conjoins with the semiconductor and a third medium such as epoxy or air. Tapering the semiconductor at the triple junction inhibits carrier formation and injection at the triple junction and thereby enables greater current carrying capacity through and greater sensitivity of the bulk area of the optically active medium. 10 figs.

  8. High-Throughput Transfer Imprinting for Organic Semiconductors

    E-Print Network [OSTI]

    Choo, Gihoon

    2013-08-06T23:59:59.000Z

    semiconductors because heat and pressure used in thermal nanoimprint do not damage functional materials. However, issues such as residual layer removal and mold contamination still limit the application of nanoimprint for organic semiconductor patterning...

  9. Stretchable semiconductor elements and stretchable electrical circuits

    DOE Patents [OSTI]

    Rogers, John A. (Champaign, IL); Khang, Dahl-Young (Seoul, KR); Menard, Etienne (Durham, NC)

    2009-07-07T23:59:59.000Z

    The invention provides methods and devices for fabricating printable semiconductor elements and assembling printable semiconductor elements onto substrate surfaces. Methods, devices and device components of the present invention are capable of generating a wide range of flexible electronic and optoelectronic devices and arrays of devices on substrates comprising polymeric materials. The present invention also provides stretchable semiconductor structures and stretchable electronic devices capable of good performance in stretched configurations.

  10. Layered semiconductor neutron detectors

    DOE Patents [OSTI]

    Mao, Samuel S; Perry, Dale L

    2013-12-10T23:59:59.000Z

    Room temperature operating solid state hand held neutron detectors integrate one or more relatively thin layers of a high neutron interaction cross-section element or materials with semiconductor detectors. The high neutron interaction cross-section element (e.g., Gd, B or Li) or materials comprising at least one high neutron interaction cross-section element can be in the form of unstructured layers or micro- or nano-structured arrays. Such architecture provides high efficiency neutron detector devices by capturing substantially more carriers produced from high energy .alpha.-particles or .gamma.-photons generated by neutron interaction.

  11. Controlled Nanoparticle Metal Phosphates (Metal = Al, Fe, Ce, and Sr) Coatings on LiCoO2 Cathode Materials

    E-Print Network [OSTI]

    Cho, Jaephil

    Controlled Nanoparticle Metal Phosphates (Metal = Al, Fe, Ce, and Sr) Coatings on LiCoO2 Cathode and annealing temperature are used for MPO4 nanoparticle coatings M = Al, Fe, Ce, and SrH on a LiCoO2 cathode, the extent of the coating coverage is influenced by the nanoparticle size or morphology. Nanoparticles AlPO4

  12. Enhanced von Weizsäcker Wang-Govind-Carter kinetic energy density functional for semiconductors

    SciTech Connect (OSTI)

    Shin, Ilgyou [Department of Chemistry, Princeton University, Princeton, New Jersey 08544-1009 (United States)] [Department of Chemistry, Princeton University, Princeton, New Jersey 08544-1009 (United States); Carter, Emily A., E-mail: eac@princeton.edu [Department of Mechanical and Aerospace Engineering, Program in Applied and Computational Mathematics, and Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey 08544-5263 (United States)

    2014-05-14T23:59:59.000Z

    We propose a new form of orbital-free (OF) kinetic energy density functional (KEDF) for semiconductors that is based on the Wang-Govind-Carter (WGC99) nonlocal KEDF. We enhance within the latter the semi-local von Weizsäcker KEDF term, which is exact for a single orbital. The enhancement factor we introduce is related to the extent to which the electron density is localized. The accuracy of the new KEDF is benchmarked against Kohn-Sham density functional theory (KSDFT) by comparing predicted energy differences between phases, equilibrium volumes, and bulk moduli for various semiconductors, along with metal-insulator phase transition pressures. We also compare point defect and (100) surface energies in silicon for a broad test of its applicability. This new KEDF accurately reproduces the exact non-interacting kinetic energy of KSDFT with only one additional adjustable parameter beyond the three parameters in the WGC99 KEDF; it exhibits good transferability between semiconducting to metallic silicon phases and between various III-V semiconductors without parameter adjustment. Overall, this KEDF is more accurate than previously proposed OF KEDFs (e.g., the Huang-Carter (HC) KEDF) for semiconductors, while the computational efficiency remains at the level of the WGC99 KEDF (several hundred times faster than the HC KEDF). This accurate, fast, and transferable new KEDF holds considerable promise for large-scale OFDFT simulations of metallic through semiconducting materials.

  13. Iron-Based Amorphous-Metals: High-Performance Corrosion-Resistant Material (HPCRM) Development

    SciTech Connect (OSTI)

    Farmer, J C; Choi, J S; Saw, C; Haslam, J; Day, D; Hailey, P; Lian, T; Rebak, R; Perepezko, J; Payer, J; Branagan, D; Beardsley, B; D'Amato, A; Aprigliano, L

    2008-01-09T23:59:59.000Z

    An overview of the High-Performance Corrosion-Resistant Materials (HPCRM) Program, which was co-sponsored by the Defense Advanced Research Projects Agency (DARPA) Defense Sciences Office (DSO) and the United States Department of Energy (DOE) Office of Civilian and Radioactive Waste Management (OCRWM), is discussed. Programmatic investigations have included a broad range of topics: alloy design and composition; materials synthesis; thermal stability; corrosion resistance; environmental cracking; mechanical properties; damage tolerance; radiation effects; and important potential applications. Amorphous alloys identified as SAM2X5 (Fe{sub 49.7}Cr{sub 17.7}Mn{sub 1.9}Mo{sub 7.4}W{sub 1.6}B{sub 15.2}C{sub 3.8}Si{sub 2.4}) and SAM1651 (Fe{sub 48}Mo{sub 14}Cr{sub 15}Y{sub 2}C{sub 15}B{sub 6}) have been produced as melt-spun ribbons, drop-cast ingots and thermal-spray coatings. Chromium (Cr), molybdenum (Mo) and tungsten (W) additions provided corrosion resistance, while boron (B) enabled glass formation. Earlier electrochemical studies of melt-spun ribbons and ingots of these amorphous alloys demonstrated outstanding passive film stability. More recently thermal-spray coatings of these amorphous alloys have been made and subjected to long-term salt-fog and immersion tests. Good corrosion resistance has been observed during salt-fog testing. Corrosion rates were measured in situ with linear polarization, while simultaneously monitoring the open-circuit corrosion potentials. Reasonably good performance was observed. The sensitivity of these measurements to electrolyte composition and temperature was determined. The high boron content of this particular amorphous metal makes this amorphous alloy an effective neutron absorber, and suitable for criticality control applications. In general, the corrosion resistance of such iron-based amorphous metals is maintained at operating temperatures up to the glass transition temperature. These materials are much harder than conventional stainless steel and nickel-based materials, and are proving to have excellent wear properties, sufficient to warrant their use in earth excavation, drilling and tunnel boring applications. Large areas have been successfully coated with these materials, with thicknesses of approximately one centimeter. The observed corrosion resistance may enable applications of importance in industries such as: oil and gas production, refining, nuclear power generation, shipping, and others.

  14. Iron-Based Amorphous Metals:The High Performance Corrosion Resistant Materials(HPCRM) Program

    SciTech Connect (OSTI)

    Farmer, J

    2007-07-09T23:59:59.000Z

    An overview of the High-Performance Corrosion-Resistant Materials (HPCRM) Program, which was co-sponsored by the Defense Advanced Research Projects Agency (DARPA) Defense Sciences Office (DSO) and the United States Department of Energy (DOE) Office of Civilian and Radioactive Waste Management (OCRWM), is discussed. Programmatic investigations have included a broad range of topics: alloy design and composition; materials synthesis; thermal stability; corrosion resistance; environmental cracking; mechanical properties; damage tolerance; radiation effects; and important potential applications. Amorphous alloys identified as SAM2X5 (Fe{sub 49.7}Cr{sub 17.7}Mn{sub 1.9}Mo{sub 7.4}W{sub 1.6}B{sub 15.2}C{sub 3.8}Si{sub 2.4}) and SAM1651 (Fe{sub 48}Mo{sub 14}Cr{sub 15}Y{sub 2}C{sub 15}B{sub 6}) have been produced as melt-spun ribbons, drop-cast ingots and thermal-spray coatings. Chromium (Cr), molybdenum (Mo) and tungsten (W) additions provided corrosion resistance, while boron (B) enabled glass formation. Earlier electrochemical studies of melt-spun ribbons and ingots of these amorphous alloys demonstrated outstanding passive film stability. More recently thermal-spray coatings of these amorphous alloys have been made and subjected to long-term salt-fog and immersion tests. Good corrosion resistance has been observed during salt-fog testing. Corrosion rates were measured in situ with linear polarization, while simultaneously monitoring the open-circuit corrosion potentials. Reasonably good performance was observed. The sensitivity of these measurements to electrolyte composition and temperature was determined. The high boron content of this particular amorphous metal makes this amorphous alloy an effective neutron absorber, and suitable for criticality control applications. In general, the corrosion resistance of such iron-based amorphous metals is maintained at operating temperatures up to the glass transition temperature. These materials are much harder than conventional stainless steel and nickel-based materials, and are proving to have excellent wear properties, sufficient to warrant their use in earth excavation, drilling and tunnel boring applications. Large areas have been successfully coated with these materials, with thicknesses of approximately one centimeter. The observed corrosion resistance may enable applications of importance in industries such as: oil and gas production, refining, nuclear power generation, shipping, and others.

  15. Preparation of a semiconductor thin film

    DOE Patents [OSTI]

    Pehnt, M.; Schulz, D.L.; Curtis, C.J.; Ginley, D.S.

    1998-01-27T23:59:59.000Z

    A process is disclosed for the preparation of a semiconductor film. The process comprises depositing nanoparticles of a semiconductor material onto a substrate whose surface temperature during nanoparticle deposition thereon is sufficient to cause substantially simultaneous fusion of the nanoparticles to thereby coalesce with each other and effectuate film growth.

  16. Preparation of a semiconductor thin film

    DOE Patents [OSTI]

    Pehnt, Martin (TuBingen, DE); Schulz, Douglas L. (Denver, CO); Curtis, Calvin J. (Lakewood, CO); Ginley, David S. (Evergreen, CO)

    1998-01-01T23:59:59.000Z

    A process for the preparation of a semiconductor film. The process comprises depositing nanoparticles of a semiconductor material onto a substrate whose surface temperature during nanoparticle deposition thereon is sufficient to cause substantially simultaneous fusion of the nanoparticles to thereby coalesce with each other and effectuate film growth.

  17. Method for removing semiconductor layers from salt substrates

    DOE Patents [OSTI]

    Shuskus, Alexander J. (West Hartford, CT); Cowher, Melvyn E. (East Brookfield, MA)

    1985-08-27T23:59:59.000Z

    A method is described for removing a CVD semiconductor layer from an alkali halide salt substrate following the deposition of the semiconductor layer. The semiconductor-substrate combination is supported on a material such as tungsten which is readily wet by the molten alkali halide. The temperature of the semiconductor-substrate combination is raised to a temperature greater than the melting temperature of the substrate but less than the temperature of the semiconductor and the substrate is melted and removed from the semiconductor by capillary action of the wettable support.

  18. Material development of polymer/metal paste for flip-chip attach interconnection technology

    SciTech Connect (OSTI)

    Roldann, J.M.; Saraf, R.F.; Sambucetti, C.J.; Cotte, J.

    1996-11-01T23:59:59.000Z

    Upon completion of the second year of this contract, we have delivered the next generation of polymer/metal composite, optimum paste H, to Endicott. We have done preliminary flip-chip type bonding at Universal Instruments, working closely with their personnel to enhance their equipment set and process. We have also shown that a PMC bond can withstand over 40% strain without effecting its electrical and mechanical properties. This resilience of the conductive polymer paste both under electrical and mechanical behavior, is a strong indication of the applicability of the material for Flip Chip Attach to organic laminates. We have also confirmed during this phase of the Contract that the Optimum Paste H can be processed and applied under normal ambient conditions, without special precautions of low temperature or inert atmospheres, a property which sets our system apart from many other commercial pastes. We would also like to remark the achievement of optimized paste properties and how these properties address the mayor issues and requirements for flip attach applications, in Table I and II of this report. Use of the PMC to build interposer for chip-testing. Due to the high electrical conductivity of the PMC, a process was developed to use a thin film layer of the paste applied to a metal cathode of an electrochemical cell, to build fully metallized thru hole arrays containing a given C-4 chip foot print. This array interposers can be used for chip test (known-good-chip) applications. This process will be described in detail at the Year-End Review Meeting in Binghanton.

  19. Spectroscopy of Charge Carriers and Traps in Field-Doped Single Crystal Organic Semiconductors

    SciTech Connect (OSTI)

    Zhu, Xiaoyang

    2014-12-10T23:59:59.000Z

    The proposed research aims to achieve quantitative, molecular level understanding of charge carriers and traps in field-doped crystalline organic semiconductors via in situ linear and nonlinear optical spectroscopy, in conjunction with transport measurements and molecular/crystal engineering. Organic semiconductors are emerging as viable materials for low-cost electronics and optoelectronics, such as organic photovoltaics (OPV), organic field effect transistors (OFETs), and organic light emitting diodes (OLEDs). Despite extensive studies spanning many decades, a clear understanding of the nature of charge carriers in organic semiconductors is still lacking. It is generally appreciated that polaron formation and charge carrier trapping are two hallmarks associated with electrical transport in organic semiconductors; the former results from the low dielectric constants and weak intermolecular electronic overlap while the latter can be attributed to the prevalence of structural disorder. These properties have lead to the common observation of low charge carrier mobilities, e.g., in the range of 10-5 - 10-3 cm2/Vs, particularly at low carrier concentrations. However, there is also growing evidence that charge carrier mobility approaching those of inorganic semiconductors and metals can exist in some crystalline organic semiconductors, such as pentacene, tetracene and rubrene. A particularly striking example is single crystal rubrene (Figure 1), in which hole mobilities well above 10 cm2/Vs have been observed in OFETs operating at room temperature. Temperature dependent transport and spectroscopic measurements both revealed evidence of free carriers in rubrene. Outstanding questions are: what are the structural features and physical properties that make rubrene so unique? How do we establish fundamental design principles for the development of other organic semiconductors of high mobility? These questions are critically important but not comprehensive, as the nature of charge carriers is known to evolve as the carrier concentration increases, due to the presence of intrinsic disorder in organic semiconductors. Thus, a complementary question is: how does the nature of charge transport change as a function of carrier concentration?

  20. Separation of C2 Hydrocarbons by Porous Materials: Metal Organic Frameworks as Platform

    SciTech Connect (OSTI)

    Banerjee, Debasis; Liu, Jun; Thallapally, Praveen K.

    2014-12-22T23:59:59.000Z

    The effective separation of small hydrocarbon molecules (C1 – C4) is an important process for petroleum industry, determining the end price of many essential commodities in our daily lives. Current technologies for separation of these molecules rely on energy intensive fractional distillation processes at cryogenic temperature, which is particularly difficult because of their similar volatility. In retrospect, adsorptive separation using solid state adsorbents might be a cost effective alternative. Several types of solid state adsorbents (e.g. zeolite molecular sieves) were tested for separation of small hydrocarbon molecules as a function of pressure, temperature or vacuum. Among different types of plausible adsorbents, metal organic frameworks (MOFs), a class of porous, crystalline, inorganic-organic hybrid materials, is particularly promising. In this brief comment article, we discuss the separation properties of different types of solid state adsorbents, with a particular emphasis on MOF based adsorbents for separation of C2 hydrocarbon molecules.

  1. Analytical model for the optical functions of amorphous semiconductors from the near-infrared to ultraviolet: Applications in thin film

    E-Print Network [OSTI]

    Deng, Xunming

    Analytical model for the optical functions of amorphous semiconductors from the near functions of thin film semiconductors are useful for two important purposes, namely, materials, reflectance, and ellipso- metric spectra obtained on the thin film semiconductors. The conventional analysis

  2. Ultraviolet GaN photodetectors on Si via oxide buffer heterostructures with integrated short period oxide-based distributed Bragg reflectors and leakage suppressing metal-oxide-semiconductor contacts

    SciTech Connect (OSTI)

    Szyszka, A., E-mail: szyszka@ihp-microelectronics.com, E-mail: adam.szyszka@pwr.wroc.pl [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); Faculty of Microsystem Electronics and Photonics, Wroclaw University of Technology, Janiszewskiego 11/17, 50-372 Wroclaw (Poland); Lupina, L.; Lupina, G.; Schubert, M. A.; Zaumseil, P. [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); Haeberlen, M.; Storck, P.; Thapa, S. B. [Siltronic, Hanns-Seidel-Platz 4, 81737 München (Germany); Schroeder, T. [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); BTU Cottbus-Senftenberg, Konrad-Zuse-Strasse 1, 03046 Cottbus (Germany)

    2014-08-28T23:59:59.000Z

    Based on a novel double step oxide buffer heterostructure approach for GaN integration on Si, we present an optimized Metal-Semiconductor-Metal (MSM)-based Ultraviolet (UV) GaN photodetector system with integrated short-period (oxide/Si) Distributed Bragg Reflector (DBR) and leakage suppressing Metal-Oxide-Semiconductor (MOS) electrode contacts. In terms of structural properties, it is demonstrated by in-situ reflection high energy electron diffraction and transmission electron microscopy-energy dispersive x-ray studies that the DBR heterostructure layers grow with high thickness homogeneity and sharp interface structures sufficient for UV applications; only minor Si diffusion into the Y{sub 2}O{sub 3} films is detected under the applied thermal growth budget. As revealed by comparative high resolution x-ray diffraction studies on GaN/oxide buffer/Si systems with and without DBR systems, the final GaN layer structure quality is not significantly influenced by the growth of the integrated DBR heterostructure. In terms of optoelectronic properties, it is demonstrated that—with respect to the basic GaN/oxide/Si system without DBR—the insertion of (a) the DBR heterostructures and (b) dark current suppressing MOS contacts enhances the photoresponsivity below the GaN band-gap related UV cut-off energy by almost up to two orders of magnitude. Given the in-situ oxide passivation capability of grown GaN surfaces and the one order of magnitude lower number of superlattice layers in case of higher refractive index contrast (oxide/Si) systems with respect to classical III-N DBR superlattices, virtual GaN substrates on Si via functional oxide buffer systems are thus a promising robust approach for future GaN-based UV detector technologies.

  3. Life-cycle Assessment of Semiconductors

    E-Print Network [OSTI]

    Boyd, Sarah B.

    2009-01-01T23:59:59.000Z

    SemiconductorThe Semiconductor Industry: Size, Growth andSemiconductor Life-cycle Environmental Impacts . . . . . . .

  4. Specification and qualification of welding procedures for metallic materials : Welding procedure test : Part 2: Arc welding of aluminium and its alloys

    E-Print Network [OSTI]

    International Organization for Standardization. Geneva

    2005-01-01T23:59:59.000Z

    Specification and qualification of welding procedures for metallic materials : Welding procedure test : Part 2: Arc welding of aluminium and its alloys

  5. Specification and qualification of welding procedures for metallic materials : Welding procedure test : Part 2: Arc welding of aluminium and its alloys : technical corrigendum 1

    E-Print Network [OSTI]

    International Organization for Standardization. Geneva

    2005-01-01T23:59:59.000Z

    Specification and qualification of welding procedures for metallic materials : Welding procedure test : Part 2: Arc welding of aluminium and its alloys : technical corrigendum 1

  6. Method for forming metal contacts

    DOE Patents [OSTI]

    Reddington, Erik; Sutter, Thomas C; Bu, Lujia; Cannon, Alexandra; Habas, Susan E; Curtis, Calvin J; Miedaner, Alexander; Ginley, David S; Van Hest, Marinus Franciscus Antonius Maria

    2013-09-17T23:59:59.000Z

    Methods of forming metal contacts with metal inks in the manufacture of photovoltaic devices are disclosed. The metal inks are selectively deposited on semiconductor coatings by inkjet and aerosol apparatus. The composite is heated to selective temperatures where the metal inks burn through the coating to form an electrical contact with the semiconductor. Metal layers are then deposited on the electrical contacts by light induced or light assisted plating.

  7. Catalyzed Water Oxidation by Solar Irradiation of Band-Gap-Narrowed Semiconductors (Part 1. Overview).

    SciTech Connect (OSTI)

    Fujita,E.; Khalifah, P.; Lymar, S.; Muckerman, J.T.; Rodgriguez, J.

    2008-03-18T23:59:59.000Z

    The objectives of this report are: (1) Investigate the catalysis of water oxidation by cobalt and manganese hydrous oxides immobilized on titania or silica nanoparticles, and dinuclear metal complexes with quinonoid ligands in order to develop a better understanding of the critical water oxidation chemistry, and rationally search for improved catalysts. (2) Optimize the light-harvesting and charge-separation abilities of stable semiconductors including both a focused effort to improve the best existing materials by investigating their structural and electronic properties using a full suite of characterization tools, and a parallel effort to discover and characterize new materials. (3) Combine these elements to examine the function of oxidation catalysts on Band-Gap-Narrowed Semiconductor (BGNSC) surfaces and elucidate the core scientific challenges to the efficient coupling of the materials functions.

  8. Systematic study of LPCVD refractory metal/silicide interconnect materials for very large scale integrated circuits

    SciTech Connect (OSTI)

    Nowrozi, M.F.

    1988-01-01T23:59:59.000Z

    Recently, refractory materials have been proposed as a strong alternative to poly-silicon and aluminum alloys as metallization systems for Very Large Scale Integrated (VLSI) circuits because of their improved performance at smaller Integrated Circuit (IC) feature size and higher interconnect current densities. However, processing and reliability problems associated with the use of refractory materials have limited their widespread acceptance. The hot-wall low-pressure chemical vapor deposition (LPCVD) of Mo and W from their respective hexacarbonyl sources has been studied as a potential remedy to such problems, in addition to providing the potential for higher throughput and better step coverage. Using deposition chemistries based on carbonyl sources, Mo and W deposits were characterized with respect to their electrical, mechanical, structural, and chemical properties as well as their compatibility with conventional IC processing. Excellent film step coverage and uniformity were obtained by low-temperature (300-350 C) deposition at pressures of 400-600 mTorr. As-deposited films were observed to be amorphous, with a resistivity of 250 and 350 microohm-cm for Mo and W, respectively.

  9. Diminished Short Channel Effects in Nanoscale Double-Gate Silicon-on-Insulator MetalOxideSemiconductor Field-Effect-Transistors

    E-Print Network [OSTI]

    Kumar, M. Jagadesh

    ) and the back-gate oxide (tb) thickness is 2 nm. The doping in the p-type body and n+ source/drain regions­Oxide­Semiconductor Field-Effect-Transistors due to Induced Back-Gate Step Potential M. Jagadesh KUMAR Ã and G. Venkateshwar surface potential profile at the back gate of an asymmetrical double gate (DG) silicon-on-insulator (SOI

  10. Semiconductor wire array structures, and solar cells and photodetectors based on such structures

    DOE Patents [OSTI]

    Kelzenberg, Michael D.; Atwater, Harry A.; Briggs, Ryan M.; Boettcher, Shannon W.; Lewis, Nathan S.; Petykiewicz, Jan A.

    2014-08-19T23:59:59.000Z

    A structure comprising an array of semiconductor structures, an infill material between the semiconductor materials, and one or more light-trapping elements is described. Photoconverters and photoelectrochemical devices based on such structure also described.

  11. Fabrication of superconducting metal-oxide textiles by heating impregnated polymeric material in a weakly oxidizing atmosphere

    SciTech Connect (OSTI)

    Van den Sype, J.S.

    1993-07-13T23:59:59.000Z

    A process is described for producing crystalline fibers, textiles or shapes comprised of YBa[sub 2]Cu[sub 3]O[sub 7[minus]x] where x varies from about 0 to about 0.4, said process comprising: (a) impregnating a preformed organic polymeric material with three metal compounds to provide metal elements in said material in substantially the atomic ratio occurring in said YBa[sub 2]Cu[sub 3]O[sub 7[minus]x]; (b) heating said impregnated material in a weakly oxidizing atmosphere containing from about 0.05% to about 2% oxygen by volume to a temperature sufficiently high to at least partially pyrolize and oxidize said organic material and at least partially oxidize said metal compounds substantially without ignition of said organic material and without formation of a molten phase or reaching a decomposition temperature of said YBa[sub 2]Cu[sub 3]O[sub 7[minus]x]; and (c) cooling the resulting material in at least a moderately oxidizing atmosphere to room temperature so as to obtain said fibers, textiles or shapes.

  12. Thermoelectric material including a multiple transition metal-doped type I clathrate crystal structure

    DOE Patents [OSTI]

    Yang, Jihui (Lakeshore, CA); Shi, Xun (Troy, MI); Bai, Shengqiang (Shanghai, CN); Zhang, Wenqing (Shanghai, CN); Chen, Lidong (Shanghai, CN); Yang, Jiong (Shanghai, CN)

    2012-01-17T23:59:59.000Z

    A thermoelectric material includes a multiple transition metal-doped type I clathrate crystal structure having the formula A.sub.8TM.sub.y.sub.1.sup.1TM.sub.y.sub.2.sup.2 . . . TM.sub.y.sub.n.sup.nM.sub.zX.sub.46-y.sub.1.sub.-y.sub.2.sub.- . . . -y.sub.n.sub.-z. In the formula, A is selected from the group consisting of barium, strontium, and europium; X is selected from the group consisting of silicon, germanium, and tin; M is selected from the group consisting of aluminum, gallium, and indium; TM.sup.1, TM.sup.2, and TM.sup.n are independently selected from the group consisting of 3d, 4d, and 5d transition metals; and y.sub.1, y.sub.2, y.sub.n and Z are actual compositions of TM.sup.1, TM.sup.2, TM.sup.n, and M, respectively. The actual compositions are based upon nominal compositions derived from the following equation: z=8q.sub.A-|.DELTA.q.sub.1|y.sub.1-|.DELTA.q.sub.2|y.sub.2- . . . -|.DELTA.q.sub.n|y.sub.n, wherein q.sub.A is a charge state of A, and wherein .DELTA.q.sub.1, .DELTA.q.sub.2, .DELTA.q.sub.n are, respectively, the nominal charge state of the first, second, and n-th TM.

  13. Graphitic carbon nitride materials: variation of structure and morphology and their use as metal-free catalysts

    E-Print Network [OSTI]

    properties of carbon nitrides, they show unexpected catalytic activity for a variety of reactions, such as for the activation of benzene, trimerization reactions, and also the activation of carbon dioxide. Model calculationsGraphitic carbon nitride materials: variation of structure and morphology and their use as metal

  14. Fabricating metal-oxide-semiconductor field-effect transistors on a polyethylene terephthalate substrate by applying low-temperature layer transfer of a single-crystalline silicon layer by meniscus force

    SciTech Connect (OSTI)

    Sakaike, Kohei; Akazawa, Muneki; Nakamura, Shogo [Department of Semiconductor Electronics and Integration Science, Graduate School of Advanced Sciences of Matter, Hiroshima University, Kagamiyama 1-3-1, Higashihiroshima, Hiroshima 739-8530 (Japan)] [Department of Semiconductor Electronics and Integration Science, Graduate School of Advanced Sciences of Matter, Hiroshima University, Kagamiyama 1-3-1, Higashihiroshima, Hiroshima 739-8530 (Japan); Higashi, Seiichiro [Department of Semiconductor Electronics and Integration Science, Graduate School of Advanced Sciences of Matter, Hiroshima University, Kagamiyama 1-3-1, Higashihiroshima, Hiroshima 739-8530 (Japan) [Department of Semiconductor Electronics and Integration Science, Graduate School of Advanced Sciences of Matter, Hiroshima University, Kagamiyama 1-3-1, Higashihiroshima, Hiroshima 739-8530 (Japan); Research Institute for Nanodevice and Bio Systems, Hiroshima University, Kagamiyama 1-4-2, Higashihiroshima, Hiroshima 739-8527 (Japan)

    2013-12-02T23:59:59.000Z

    A low-temperature local-layer technique for transferring a single-crystalline silicon (c-Si) film by using a meniscus force was proposed, and an n-channel metal-oxide-semiconductor field-effect transistor (MOSFET) was fabricated on polyethylene terephthalate (PET) substrate. It was demonstrated that it is possible to transfer and form c-Si films in the required shape at the required position on PET substrates at extremely low temperatures by utilizing a meniscus force. The proposed technique for layer transfer was applied for fabricating high-performance c-Si MOSFETs on a PET substrate. The fabricated MOSFET showed a high on/off ratio of more than 10{sup 8} and a high field-effect mobility of 609 cm{sup 2} V{sup ?1} s{sup ?1}.

  15. Optical temperature indicator using thermochromic semiconductors

    DOE Patents [OSTI]

    Kronberg, J.W.

    1995-01-01T23:59:59.000Z

    A reversible optical temperature indicator utilizes thermochromic semiconductors which vary in color in response to various temperature levels. The thermochromic material is enclosed in an enamel which provides protection and prevents breakdown at higher temperatures. Cadmium sulfide is the preferred semiconductor material. The indicator may be utilized as a sign or in a striped arrangement to clearly provide a warning to a user. The various color responses provide multiple levels of alarm.

  16. Optical temperature sensor using thermochromic semiconductors

    DOE Patents [OSTI]

    Kronberg, James W. (Aiken, SC)

    1998-01-01T23:59:59.000Z

    An optical temperature measuring device utilizes thermochromic semiconductors which vary in color in response to changes in temperature. The thermochromic material is sealed in a glass matrix which allows the temperature sensor to detect high temperatures without breakdown. Cuprous oxide and cadmium sulfide are among the semiconductor materials which provide the best results. The changes in color may be detected visually using a sensor chip and an accompanying color card.

  17. Optical temperature sensor using thermochromic semiconductors

    DOE Patents [OSTI]

    Kronberg, James W. (108 Independent Blvd., Aiken, SC 29801)

    1996-01-01T23:59:59.000Z

    An optical temperature measuring device utilizes thermochromic semiconductors which vary in color in response to changes in temperature. The thermochromic material is sealed in a glass matrix which allows the temperature sensor to detect high temperatures without breakdown. Cuprous oxide and cadmium sulfide are among the semiconductor materials which provide the best results. The changes in color may be detected visually or by utilizing an optical fiber and an electrical sensing circuit.

  18. Optical temperature indicator using thermochromic semiconductors

    DOE Patents [OSTI]

    Kronberg, James W. (108 Independent Blvd., Aiken, SC 29801)

    1996-01-01T23:59:59.000Z

    A reversible optical temperature indicator utilizes thermochromic semiconductors which vary in color in response to various temperature levels. The thermochromic material is enclosed in an enamel which provides protection and prevents breakdown at higher temperatures. Cadmium sulfide is the preferred semiconductor material. The indicator may be utilized as a sign or in a striped arrangement to clearly provide a warning to a user. The various color responses provide multiple levels of alarm.

  19. Optical temperature sensor using thermochromic semiconductors

    DOE Patents [OSTI]

    Kronberg, J.W.

    1996-08-20T23:59:59.000Z

    An optical temperature measuring device utilizes thermochromic semiconductors which vary in color in response to changes in temperature. The thermochromic material is sealed in a glass matrix which allows the temperature sensor to detect high temperatures without breakdown. Cuprous oxide and cadmium sulfide are among the semiconductor materials which provide the best results. The changes in color may be detected visually or by utilizing an optical fiber and an electrical sensing circuit. 7 figs.

  20. Optical temperature sensor using thermochromic semiconductors

    DOE Patents [OSTI]

    Kronberg, J.W.

    1998-06-30T23:59:59.000Z

    An optical temperature measuring device utilizes thermochromic semiconductors which vary in color in response to changes in temperature. The thermochromic material is sealed in a glass matrix which allows the temperature sensor to detect high temperatures without breakdown. Cuprous oxide and cadmium sulfide are among the semiconductor materials which provide the best results. The changes in color may be detected visually using a sensor chip and an accompanying color card. 8 figs.

  1. Sandia National Laboratories: Light Creation Materials

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    TechnologiesLight Creation Materials Light Creation Materials Overview of SSL Light Creation Materials Different families of inorganic semiconductor materials can...

  2. Synthesis of Thermal Interface Materials Made of Metal Decorated Carbon Nanotubes and Polymers

    E-Print Network [OSTI]

    Okoth, Marion Odul

    2011-10-21T23:59:59.000Z

    -Methly-2-Pyrrolidone (NMP). The metals used for this experiment were copper (Cu), tin (Sn), and nickel (Ni). The metal nanoparticles were seeded using functionalized MWCNTs as templates. Once seeded, the nanotubes and polymer composites were made...

  3. Wide band gap semiconductor templates

    DOE Patents [OSTI]

    Arendt, Paul N. (Los Alamos, NM); Stan, Liliana (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM); DePaula, Raymond F. (Santa Fe, NM); Usov, Igor O. (Los Alamos, NM)

    2010-12-14T23:59:59.000Z

    The present invention relates to a thin film structure based on an epitaxial (111)-oriented rare earth-Group IVB oxide on the cubic (001) MgO terminated surface and the ion-beam-assisted deposition ("IBAD") techniques that are amendable to be over coated by semiconductors with hexagonal crystal structures. The IBAD magnesium oxide ("MgO") technology, in conjunction with certain template materials, is used to fabricate the desired thin film array. Similarly, IBAD MgO with appropriate template layers can be used for semiconductors with cubic type crystal structures.

  4. Metal aminoboranes

    DOE Patents [OSTI]

    Burrell, Anthony K.; Davis, Benjamin J.; Thorn, David L.; Gordon, John C.; Baker, R. Thomas; Semelsberger, Troy Allen; Tumas, William; Diyabalanage, Himashinie Vichalya; Shrestha, Roshan P.

    2010-05-11T23:59:59.000Z

    Metal aminoboranes of the formula M(NH2BH3)n have been synthesized. Metal aminoboranes are hydrogen storage materials. Metal aminoboranes are also precursors for synthesizing other metal aminoboranes. Metal aminoboranes can be dehydrogenated to form hydrogen and a reaction product. The reaction product can react with hydrogen to form a hydrogen storage material. Metal aminoboranes can be included in a kit.

  5. Thin film studies of planar transition metal complexes 

    E-Print Network [OSTI]

    Whyte, Alex

    2013-06-29T23:59:59.000Z

    At present the field of molecular electronics - also known as molecular semiconductors, organic semiconductors, plastic electronics or organic electronics - is dominated by organic materials, both polymeric and molecular, ...

  6. (Data in thousand metric tons of silicon content unless otherwise noted) Domestic Production and Use: Estimated value of silicon metal and alloys (excluding semiconductor-grade silicon)

    E-Print Network [OSTI]

    metal: Brazil, 37%; South Africa, 25%; Canada, 14%; Norway, 6%; and other, 18%. Total: Brazil, 20%; China, 16%; South Africa, 13%; Canada, 12%; and other, 39%. Tariff: Item Number Normal Trade Relations energy costs. Demand for silicon metal comes primarily from the aluminum and chemical industries

  7. Semiconductor bridge (SCB) igniter

    DOE Patents [OSTI]

    Bickes, Jr., Robert W. (Albuquerque, NM); Schwarz, Alfred C. (Albuquerque, NM)

    1987-01-01T23:59:59.000Z

    In an explosive device comprising an explosive material which can be made to explode upon activation by activation means in contact therewith; electrical activation means adaptable for activating said explosive material such that it explodes; and electrical circuitry in operation association with said activation means; there is an improvement wherein said activation means is an electrical material which, at an elevated temperature, has a negative temperature coefficient of electrical resistivity and which has a shape and size and an area of contact with said explosive material sufficient that it has an electrical resistance which will match the resistance requirements of said associated electrical circuitry when said electrical material is operationally associated with said circuitry, and wherein said electrical material is polycrystalline; or said electrical material is crystalline and (a) is mounted on a lattice matched substrate or (b) is partially covered with an intimately contacting metallization area which defines its area of contact with said explosive material.

  8. Thermal Issues in Casimir Forces Between Conductors and Semiconductors

    E-Print Network [OSTI]

    K. A. Milton; Iver Brevik; Simen A. Ellingsen

    2012-07-20T23:59:59.000Z

    The Casimir effect between metal surfaces has now been well-verified at the few-percent level experimentally. However, the temperature dependence has never been observed in the laboratory, since all experiments are conducted at room temperature. The temperature dependence for the related Casimir-Polder force between an atom and a bulk material has, in contrast, been observed between a BEC and a silica substrate, with the environment and the silica held at different temperatures. There is a controversy about the temperature dependence for the force between metals, having to do with the magnitude of the linear temperature term for both low and high temperature, the latter being most prominent at large distances. There are also related anomalies pertaining to semiconductors. The status of this controversy, and of the relevant experiments, are reviewed in this report.

  9. Infrared spectroscopy of novel semiconductors /

    E-Print Network [OSTI]

    Chapler, Brian Caleb

    2014-01-01T23:59:59.000Z

    dilute magnetic semiconductor . . . . . . . . 1 1.1.1in the topological semiconductors Bi2Te3 and Mn—dopedM. Fundamentals of semiconductors. Springer-Verlag, Berlin,

  10. Novel room temperature ferromagnetic semiconductors

    E-Print Network [OSTI]

    Gupta, Amita

    2004-01-01T23:59:59.000Z

    Spin Related Phenomena in Semiconductors, (27-28 Jan 1997,FERROMAGNETIC SEMICONDUCTORS Amita Gupta Stockholm, Junedata are processed by semiconductor chips, and stored in the

  11. Investigation of redox processes at semiconductor electrode liquid junctions

    SciTech Connect (OSTI)

    Koval, C.A.

    1990-08-01T23:59:59.000Z

    Research in fundamental aspects of photoelectrochemical cells has been in the following areas: chemical probes for hot carrier processes, electrostatic theory for describing electrical interactions at interfaces, and kinetics of electron transfer at ideal semiconductor solution interfaces. Our goal is to achieve a better understanding of dark and photo-induced current flow at the semiconductor electrode/redox electrolyte interface (SEI) so that devices and processes utilizing this interface for solar energy conversion can be developed or improved. Our most important accomplishment has been the development of a redox system capable of detecting hot electrons at the p-InP/acetonitrile interface. Also, we have examined electrostatic theory for the image potential of an ion as a function of distance from the SEI. Finally, our group was one of the first to realize that the 2-dimensional metal chalcogenides (MC) are excellent materials for fundamental studies of electron transfer at the SEI. One of the chief potential advantages for use of MC's is the formation of semiconductor/liquid junctions with nearly ideal electrochemical properties. 27 refs., 1 fig.

  12. Optical temperature sensor using thermochromic semiconductors

    DOE Patents [OSTI]

    Kronberg, J.W.

    1994-01-01T23:59:59.000Z

    Optical thermometry is a growing technological field which exploits the ability of certain materials to change their optical properties with temperature. A subclass of such materials are those which change their color as a reversible and reproducible function of temperature. These materials are thermochromic. This invention is a composition to measure temperature utilizing thermochromic semiconductors.

  13. Efficient Heat Storage Materials: Metallic Composites Phase-Change Materials for High-Temperature Thermal Energy Storage

    SciTech Connect (OSTI)

    None

    2011-11-21T23:59:59.000Z

    HEATS Project: MIT is developing efficient heat storage materials for use in solar and nuclear power plants. Heat storage materials are critical to the energy storage process. In solar thermal storage systems, heat can be stored in these materials during the day and released at night—when the sun’s not out—to drive a turbine and produce electricity. In nuclear storage systems, heat can be stored in these materials at night and released to produce electricity during daytime peak-demand hours. MIT is designing nanostructured heat storage materials that can store a large amount of heat per unit mass and volume. To do this, MIT is using phase change materials, which absorb a large amount of latent heat to melt from solid to liquid. MIT’s heat storage materials are designed to melt at high temperatures and conduct heat well—this makes them efficient at storing and releasing heat and enhances the overall efficiency of the thermal storage and energy-generation process. MIT’s low-cost heat storage materials also have a long life cycle, which further enhances their efficiency.

  14. Bi-Se doped with Cu, p-type semiconductor

    DOE Patents [OSTI]

    Bhattacharya, Raghu Nath; Phok, Sovannary; Parilla, Philip Anthony

    2013-08-20T23:59:59.000Z

    A Bi--Se doped with Cu, p-type semiconductor, preferably used as an absorber material in a photovoltaic device. Preferably the semiconductor has at least 20 molar percent Cu. In a preferred embodiment, the semiconductor comprises at least 28 molar percent of Cu. In one embodiment, the semiconductor comprises a molar percentage of Cu and Bi whereby the molar percentage of Cu divided by the molar percentage of Bi is greater than 1.2. In a preferred embodiment, the semiconductor is manufactured as a thin film having a thickness less than 600 nm.

  15. Metal hydrides as electrode/catalyst materials for oxygen evolution/reduction in electrochemical devices

    DOE Patents [OSTI]

    Bugga, Ratnakumar V. (Arcadia, CA); Halpert, Gerald (Pasadena, CA); Fultz, Brent (Pasadena, CA); Witham, Charles K. (Pasadena, CA); Bowman, Robert C. (La Mesa, CA); Hightower, Adrian (Whittier, CA)

    1997-01-01T23:59:59.000Z

    An at least ternary metal alloy of the formula, AB.sub.(5-Y)X(.sub.y), is claimed. In this formula, A is selected from the rare earth elements, B is selected from the elements of groups 8, 9, and 10 of the periodic table of the elements, and X includes at least one of the following: antimony, arsenic, and bismuth. Ternary or higher-order substitutions, to the base AB.sub.5 alloys, that form strong kinetic interactions with the predominant metals in the base metal hydride are used to form metal alloys with high structural integrity after multiple cycles of hydrogen sorption.

  16. Synthesis of thin films and materials utilizing a gaseous catalyst

    DOE Patents [OSTI]

    Morse, Daniel E; Schwenzer, Birgit; Gomm, John R; Roth, Kristian M; Heiken, Brandon; Brutchey, Richard

    2013-10-29T23:59:59.000Z

    A method for the fabrication of nanostructured semiconducting, photoconductive, photovoltaic, optoelectronic and electrical battery thin films and materials at low temperature, with no molecular template and no organic contaminants. High-quality metal oxide semiconductor, photovoltaic and optoelectronic materials can be fabricated with nanometer-scale dimensions and high dopant densities through the use of low-temperature biologically inspired synthesis routes, without the use of any biological or biochemical templates.

  17. Investigation of the impact of insulator material on the performance of dissimilar electrode metal-insulator-metal diodes

    SciTech Connect (OSTI)

    Alimardani, Nasir; Tan, Cheng; Lampert, Benjamin P.; Conley, John F., E-mail: jconley@eecs.oregonstate.edu [School of Electrical Engineering and Computer Science, Oregon State University, Corvallis, Oregon 97331 (United States); King, Sean W. [Logic Technology Development, Intel Corporation, Hillsboro, Oregon 97124 (United States); French, Benjamin L. [Ocotillo Materials Laboratory, Intel Corporation, Chandler, Arizona 85248 (United States)

    2014-07-14T23:59:59.000Z

    The performance of thin film metal-insulator-metal (MIM) diodes is investigated for a variety of large and small electron affinity insulators using ultrasmooth amorphous metal as the bottom electrode. Nb{sub 2}O{sub 5}, Ta{sub 2}O{sub 5}, ZrO{sub 2}, HfO{sub 2}, Al{sub 2}O{sub 3}, and SiO{sub 2} amorphous insulators are deposited via atomic layer deposition (ALD). Reflection electron energy loss spectroscopy (REELS) is utilized to measure the band-gap energy (E{sub G}) and energy position of intrinsic sub-gap defect states for each insulator. E{sub G} of as-deposited ALD insulators are found to be Nb{sub 2}O{sub 5}?=?3.8?eV, Ta{sub 2}O{sub 5}?=?4.4?eV, ZrO{sub 2}?=?5.4?eV, HfO{sub 2}?=?5.6?eV, Al{sub 2}O{sub 3}?=?6.4?eV, and SiO{sub 2}?=?8.8?eV with uncertainty of ±0.2?eV. Current vs. voltage asymmetry, non-linearity, turn-on voltage, and dominant conduction mechanisms are compared. Al{sub 2}O{sub 3} and SiO{sub 2} are found to operate based on Fowler-Nordheim tunneling. Al{sub 2}O{sub 3} shows the highest asymmetry. ZrO{sub 2}, Nb{sub 2}O{sub 5}, and Ta{sub 2}O{sub 5} based diodes are found to be dominated by Frenkel-Poole emission at large biases and exhibit lower asymmetry. The electrically estimated trap energy levels for defects that dominate Frenkel-Poole conduction are found to be consistent with the energy levels of surface oxygen vacancy defects observed in REELS measurements. For HfO{sub 2}, conduction is found to be a mix of trap assisted tunneling and Frenkel-Poole emission. Insulator selection criteria in regards to MIM diodes applications are discussed.

  18. Trending: Metal Oxo Bonds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    including materials science, chemistry, and biology. Highly covalent metal-oxygen multiple bonds (metal oxos) are the building blocks of metal oxides and have a bearing...

  19. Impact of GaN cap on charges in Al?O?/(GaN/)AlGaN/GaN metal-oxide-semiconductor heterostructures analyzed by means of capacitance measurements and simulations

    SciTech Connect (OSTI)

    ?apajna, M., E-mail: milan.tapajna@savba.sk; Jurkovi?, M.; Válik, L.; Haš?ík, Š.; Gregušová, D.; Kuzmík, J. [Institute of Electrical Engineering, Slovak Academy of Sciences, Dúbravská cesta 9, 841 04 Bratislava (Slovakia); Brunner, F.; Cho, E.-M. [Ferdinand-Braun-Institut, Leibniz Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Strasse 4, 12489 Berlin (Germany); Hashizume, T. [Research Center for Integrated Quantum Electronics (RCIQE), Hokkaido University, 060-0814 Sapporo, Japan and JST-CREST, 102-0075 Tokyo (Japan)

    2014-09-14T23:59:59.000Z

    Oxide/semiconductor interface trap density (D{sub it}) and net charge of Al?O?/(GaN)/AlGaN/GaN metal-oxide-semiconductor high-electron mobility transistor (MOS-HEMT) structures with and without GaN cap were comparatively analyzed using comprehensive capacitance measurements and simulations. D{sub it} distribution was determined in full band gap of the barrier using combination of three complementary capacitance techniques. A remarkably higher D{sub it} (?5–8?×?10¹²eV?¹?cm?²) was found at trap energies ranging from EC-0.5 to 1?eV for structure with GaN cap compared to that (D{sub it}???2–3?×?10¹²eV?¹?cm?²) where the GaN cap was selectively etched away. D{sub it} distributions were then used for simulation of capacitance-voltage characteristics. A good agreement between experimental and simulated capacitance-voltage characteristics affected by interface traps suggests (i) that very high D{sub it} (>10¹³eV?¹?cm?²) close to the barrier conduction band edge hampers accumulation of free electron in the barrier layer and (ii) the higher D{sub it} centered about EC-0.6?eV can solely account for the increased C-V hysteresis observed for MOS-HEMT structure with GaN cap. Analysis of the threshold voltage dependence on Al?O? thickness for both MOS-HEMT structures suggests that (i) positive charge, which compensates the surface polarization, is not necessarily formed during the growth of III-N heterostructure, and (ii) its density is similar to the total surface polarization charge of the GaN/AlGaN barrier, rather than surface polarization of the top GaN layer only. Some constraints for the positive surface compensating charge are discussed.

  20. Intrinsic Magnetism of Grain Boundaries in Two-dimensional Metal Dichalcogenides

    E-Print Network [OSTI]

    Zhang, Zhuhua; Crespi, Vincent H; Yakobson, Boris I

    2013-01-01T23:59:59.000Z

    Grain boundaries (GBs) are structural imperfections that typically degrade the performance of materials. Here we show that dislocations and GBs in two-dimensional (2D) metal dichalcogenides MX2 (M = Mo, W; X = S, Se) can actually improve the material by giving it a qualitatively new physical property: magnetism. The dislocations studied all have a substantial magnetic moment of ~1 Bohr magneton. In contrast, dislocations in other well-studied 2D materials are typically non-magnetic. GBs composed of pentagon-heptagon pairs interact ferromagnetically and transition from semiconductor to half-metal or metal as a function of tilt angle and/or doping level. When the tilt angle exceeds 47{\\deg} the structural energetics favor square-octagon pairs and the GB becomes an antiferromagnetic semiconductor. These exceptional magnetic properties arise from an interplay of dislocation-induced localized states, doping, and locally unbalanced stoichiometry. Purposeful engineering of topological GBs may be able to convert MX2 ...

  1. Photovoltaic healing of non-uniformities in semiconductor devices

    DOE Patents [OSTI]

    Karpov, Victor G.; Roussillon, Yann; Shvydka, Diana; Compaan, Alvin D.; Giolando, Dean M.

    2006-08-29T23:59:59.000Z

    A method of making a photovoltaic device using light energy and a solution to normalize electric potential variations in the device. A semiconductor layer having nonuniformities comprising areas of aberrant electric potential deviating from the electric potential of the top surface of the semiconductor is deposited onto a substrate layer. A solution containing an electrolyte, at least one bonding material, and positive and negative ions is applied over the top surface of the semiconductor. Light energy is applied to generate photovoltage in the semiconductor, causing a redistribution of the ions and the bonding material to the areas of aberrant electric potential. The bonding material selectively bonds to the nonuniformities in a manner such that the electric potential of the nonuniformities is normalized relative to the electric potential of the top surface of the semiconductor layer. A conductive electrode layer is then deposited over the top surface of the semiconductor layer.

  2. Impurity gettering in semiconductors

    DOE Patents [OSTI]

    Sopori, B.L.

    1995-06-20T23:59:59.000Z

    A process for impurity gettering in a semiconductor substrate or device such as a silicon substrate or device is disclosed. The process comprises hydrogenating the substrate or device at the back side thereof with sufficient intensity and for a time period sufficient to produce a damaged back side. Thereafter, the substrate or device is illuminated with electromagnetic radiation at an intensity and for a time period sufficient to cause the impurities to diffuse to the back side and alloy with a metal there present to form a contact and capture the impurities. The impurity gettering process also can function to simultaneously passivate defects within the substrate or device, with the defects likewise diffusing to the back side for simultaneous passivation. Simultaneously, substantially all hydrogen-induced damage on the back side of the substrate or device is likewise annihilated. Also taught is an alternate process comprising thermal treatment after hydrogenation of the substrate or device at a temperature of from about 500 C to about 700 C for a time period sufficient to cause the impurities to diffuse to the damaged back side thereof for subsequent capture by an alloying metal. 1 fig.

  3. Impurity gettering in semiconductors

    DOE Patents [OSTI]

    Sopori, Bhushan L. (Denver, CO)

    1995-01-01T23:59:59.000Z

    A process for impurity gettering in a semiconductor substrate or device such as a silicon substrate or device. The process comprises hydrogenating the substrate or device at the back side thereof with sufficient intensity and for a time period sufficient to produce a damaged back side. Thereafter, the substrate or device is illuminated with electromagnetic radiation at an intensity and for a time period sufficient to cause the impurities to diffuse to the back side and alloy with a metal there present to form a contact and capture the impurities. The impurity gettering process also can function to simultaneously passivate defects within the substrate or device, with the defects likewise diffusing to the back side for simultaneous passivation. Simultaneously, substantially all hydrogen-induced damage on the back side of the substrate or device is likewise annihilated. Also taught is an alternate process comprising thermal treatment after hydrogenation of the substrate or device at a temperature of from about 500.degree. C. to about 700.degree. C. for a time period sufficient to cause the impurities to diffuse to the damaged back side thereof for subsequent capture by an alloying metal.

  4. Abstract--The electrical properties of the PVD AlN have been investigated by means of metal-insulator-semiconductor

    E-Print Network [OSTI]

    Technische Universiteit Delft

    to reduce the self-heating in silicon-on-glass bipolar junction transistors [15]. These devicesAbstract--The electrical properties of the PVD AlN have been investigated by means of metal silicon. In this paper the electrical properties of the PVD AlN when deposited on silicon have been

  5. Controlled growth of semiconductor crystals

    DOE Patents [OSTI]

    Bourret-Courchesne, E.D.

    1992-07-21T23:59:59.000Z

    A method is disclosed for growth of III-V, II-VI and related semiconductor single crystals that suppresses random nucleation and sticking of the semiconductor melt at the crucible walls. Small pieces of an oxide of boron B[sub x]O[sub y] are dispersed throughout the comminuted solid semiconductor charge in the crucible, with the oxide of boron preferably having water content of at least 600 ppm. The crucible temperature is first raised to a temperature greater than the melt temperature T[sub m1] of the oxide of boron (T[sub m1]=723 K for boron oxide B[sub 2]O[sub 3]), and the oxide of boron is allowed to melt and form a reasonably uniform liquid layer between the crucible walls and bottom surfaces and the still-solid semiconductor charge. The temperature is then raised to approximately the melt temperature T[sub m2] of the semiconductor charge material, and crystal growth proceeds by a liquid encapsulated, vertical gradient freeze process. About half of the crystals grown have a dislocation density of less than 1000/cm[sup 2]. If the oxide of boron has water content less than 600 ppm, the crucible material should include boron nitride, a layer of the inner surface of the crucible should be oxidized before the oxide of boron in the crucible charge is melted, and the sum of thicknesses of the solid boron oxide layer and liquid boron oxide layer should be at least 50 [mu]m. 7 figs.

  6. Controlled growth of semiconductor crystals

    DOE Patents [OSTI]

    Bourret-Courchesne, Edith D. (Richmond, CA)

    1992-01-01T23:59:59.000Z

    A method for growth of III-V, II-VI and related semiconductor single crystals that suppresses random nucleation and sticking of the semiconductor melt at the crucible walls. Small pieces of an oxide of boron B.sub.x O.sub.y are dispersed throughout the comminuted solid semiconductor charge in the crucible, with the oxide of boron preferably having water content of at least 600 ppm. The crucible temperature is first raised to a temperature greater than the melt temperature T.sub.m1 of the oxide of boron (T.sub.m1 =723.degree. K. for boron oxide B.sub.2 O.sub.3), and the oxide of boron is allowed to melt and form a reasonably uniform liquid layer between the crucible walls and bottom surfaces and the still-solid semiconductor charge. The temperature is then raised to approximately the melt temperature T.sub.m2 of the semiconductor charge material, and crystal growth proceeds by a liquid encapsulated, vertical gradient freeze process. About half of the crystals grown have a dislocation density of less than 1000/cm.sup.2. If the oxide of boron has water content less than 600 ppm, the crucible material should include boron nitride, a layer of the inner surface of the crucible should be oxidized before the oxide of boron in the crucible charge is melted, and the sum of thicknesses of the solid boron oxide layer and liquid boron oxide layer should be at least 50 .mu.m.

  7. Preparation of III-V semiconductor nanocrystals

    DOE Patents [OSTI]

    Alivisatos, A.P.; Olshavsky, M.A.

    1996-04-09T23:59:59.000Z

    Nanometer-scale crystals of III-V semiconductors are disclosed. They are prepared by reacting a group III metal source with a group V anion source in a liquid phase at elevated temperature in the presence of a crystallite growth terminator such as pyridine or quinoline. 4 figs.

  8. Preparation of III-V semiconductor nanocrystals

    DOE Patents [OSTI]

    Alivisatos, A. Paul (Berkeley, CA); Olshavsky, Michael A. (Brunswick, OH)

    1996-01-01T23:59:59.000Z

    Nanometer-scale crystals of III-V semiconductors are disclosed, They are prepared by reacting a group III metal source with a group V anion source in a liquid phase at elevated temperature in the presence of a crystallite growth terminator such as pyridine or quinoline.

  9. Tetratopic phenyl compounds, related metal-organic framework materials and post-assembly elaboration

    DOE Patents [OSTI]

    Farha, Omar K; Hupp, Joseph T

    2013-06-25T23:59:59.000Z

    Disclosed are tetratopic carboxylic acid phenyl for use in metal-organic framework compounds. These compounds are useful in catalysis, gas storage, sensing, biological imaging, drug delivery and gas adsorption separation.

  10. Tetratopic phenyl compounds, related metal-organic framework materials and post-assembly elaboration

    DOE Patents [OSTI]

    Farha, Omar K.; Hupp, Joseph T.

    2012-09-11T23:59:59.000Z

    Disclosed are tetratopic carboxylic acid phenyl for use in metal-organic framework compounds. These compounds are useful in catalysis, gas storage, sensing, biological imaging, drug delivery and gas adsorption separation.

  11. Improving nickel metal hydride batteries through research in negative electrode corrosion control and novel electrode materials 

    E-Print Network [OSTI]

    Alexander, Michael Scott

    1997-01-01T23:59:59.000Z

    on the Adsorption of Hydrogen on and Absorption into Metal, Alloys, and Intermetallics, The Electrochemical Society, PV 97-16, p. 277. vn1 TABLE OF CONTENTS ABSTRACT Page DEDICATION. lv ACKNOWLEGEMENTS . TABLE OF CONTENTS vnr LIST OF FIGURES. . LIST... of a new family of the intermetallic alloys containing one transition metal (4, 7, 8-10). The major family of such intermetallic alloys and their hydrides are listed in Table 1. 2 which also shows the gravimetric and volumetric hydrogen density...

  12. Operations improvement in a semiconductor capital equipment manufacturing plant : component level and assembly level inventory management

    E-Print Network [OSTI]

    Wu, Yiming, M. Eng. Massachusetts Institute of Technology

    2012-01-01T23:59:59.000Z

    Semiconductor capital equipment is manufactured in a high-mix and low-volume environment at Varian Semiconductor Equipment business unit of Applied Materials. Due to the demand growth over the past years, Varian has been ...

  13. Unitary lens semiconductor device

    DOE Patents [OSTI]

    Lear, Kevin L. (Albuquerque, NM)

    1997-01-01T23:59:59.000Z

    A unitary lens semiconductor device and method. The unitary lens semiconductor device is provided with at least one semiconductor layer having a composition varying in the growth direction for unitarily forming one or more lenses in the semiconductor layer. Unitary lens semiconductor devices may be formed as light-processing devices such as microlenses, and as light-active devices such as light-emitting diodes, photodetectors, resonant-cavity light-emitting diodes, vertical-cavity surface-emitting lasers, and resonant cavity photodetectors.

  14. Acquisition of material properties in production for sheet metal forming processes

    SciTech Connect (OSTI)

    Heingärtner, Jörg; Hora, Pavel [Institute of Virtual Manufacturing, ETH Zurich (Switzerland); Neumann, Anja; Hortig, Dirk [Daimler AG, Sindelfingen (Germany); Rencki, Yasar [Franke Technology Ltd, Aarburg (Switzerland)

    2013-12-16T23:59:59.000Z

    In past work a measurement system for the in-line acquisition of material properties was developed at IVP. This system is based on the non-destructive eddy-current principle. Using this system, a 100% control of material properties of the processed material is possible. The system can be used for ferromagnetic materials like standard steels as well as paramagnetic materials like Aluminum and stainless steel. Used as an in-line measurement system, it can be configured as a stand-alone system to control material properties and sort out inapplicable material or as part of a control system of the forming process. In both cases, the acquired data can be used as input data for numerical simulations, e.g. stochastic simulations based on real world data.

  15. L{sub g}?=?100?nm In{sub 0.7}Ga{sub 0.3}As quantum well metal-oxide semiconductor field-effect transistors with atomic layer deposited beryllium oxide as interfacial layer

    SciTech Connect (OSTI)

    Koh, D., E-mail: dh.koh@utexas.edu, E-mail: Taewoo.Kim@sematech.org [Department of Electrical and Computer Engineering, Microelectronics Research Center, The University of Texas at Austin, Austin, Texas 78758 (United States); SEMATECH, Inc., Albany, New York 12203 (United States); Kwon, H. M. [Department of Electronics Engineering, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Kim, T.-W., E-mail: dh.koh@utexas.edu, E-mail: Taewoo.Kim@sematech.org; Veksler, D.; Gilmer, D.; Kirsch, P. D. [SEMATECH, Inc., Albany, New York 12203 (United States); Kim, D.-H. [SEMATECH, Inc., Albany, New York 12203 (United States); GLOBALFOUNDRIES, Malta, New York 12020 (United States); Hudnall, Todd W. [Department of Chemistry and Biochemistry, Texas State University, San Marcos, Texas, 78666 (United States); Bielawski, Christopher W. [Department of Chemistry and Biochemistry, The University of Texas at Austin, Austin, Texas 78712 (United States); Maszara, W. [GLOBALFOUNDRIES, Santa Clara, California 95054 (United States); Banerjee, S. K. [Department of Electrical and Computer Engineering, Microelectronics Research Center, The University of Texas at Austin, Austin, Texas 78758 (United States)

    2014-04-21T23:59:59.000Z

    In this study, we have fabricated nanometer-scale channel length quantum-well (QW) metal-oxide-semiconductor field effect transistors (MOSFETs) incorporating beryllium oxide (BeO) as an interfacial layer. BeO has high thermal stability, excellent electrical insulating characteristics, and a large band-gap, which make it an attractive candidate for use as a gate dielectric in making MOSFETs. BeO can also act as a good diffusion barrier to oxygen owing to its small atomic bonding length. In this work, we have fabricated In{sub 0.53}Ga{sub 0.47}As MOS capacitors with BeO and Al{sub 2}O{sub 3} and compared their electrical characteristics. As interface passivation layer, BeO/HfO{sub 2} bilayer gate stack presented effective oxide thickness less 1 nm. Furthermore, we have demonstrated In{sub 0.7}Ga{sub 0.3}As QW MOSFETs with a BeO/HfO{sub 2} dielectric, showing a sub-threshold slope of 100?mV/dec, and a transconductance (g{sub m,max}) of 1.1 mS/?m, while displaying low values of gate leakage current. These results highlight the potential of atomic layer deposited BeO for use as a gate dielectric or interface passivation layer for III–V MOSFETs at the 7?nm technology node and/or beyond.

  16. Methods and devices for fabricating and assembling printable semiconductor elements

    DOE Patents [OSTI]

    Nuzzo, Ralph G. (Champaign, IL); Rogers, John A. (Champaign, IL); Menard, Etienne (Urbana, IL); Lee, Keon Jae (Savoy, IL); Khang, Dahl-Young (Urbana, IL); Sun, Yugang (Champaign, IL); Meitl, Matthew (Champaign, IL); Zhu, Zhengtao (Urbana, IL)

    2009-11-24T23:59:59.000Z

    The invention provides methods and devices for fabricating printable semiconductor elements and assembling printable semiconductor elements onto substrate surfaces. Methods, devices and device components of the present invention are capable of generating a wide range of flexible electronic and optoelectronic devices and arrays of devices on substrates comprising polymeric materials. The present invention also provides stretchable semiconductor structures and stretchable electronic devices capable of good performance in stretched configurations.

  17. Methods and devices for fabricating and assembling printable semiconductor elements

    DOE Patents [OSTI]

    Nuzzo, Ralph G; Rogers, John A; Menard, Etienne; Lee, Keon Jae; Khang, Dahl-Young; Sun, Yugang; Meitl, Matthew; Zhu, Zhengtao

    2014-03-04T23:59:59.000Z

    The invention provides methods and devices for fabricating printable semiconductor elements and assembling printable semiconductor elements onto substrate surfaces. Methods, devices and device components of the present invention are capable of generating a wide range of flexible electronic and optoelectronic devices and arrays of devices on substrates comprising polymeric materials. The present invention also provides stretchable semiconductor structures and stretchable electronic devices capable of good performance in stretched configurations.

  18. Deposition method for producing silicon carbide high-temperature semiconductors

    DOE Patents [OSTI]

    Hsu, George C. (La Crescenta, CA); Rohatgi, Naresh K. (W. Corine, CA)

    1987-01-01T23:59:59.000Z

    An improved deposition method for producing silicon carbide high-temperature semiconductor material comprising placing a semiconductor substrate composed of silicon carbide in a fluidized bed silicon carbide deposition reactor, fluidizing the bed particles by hydrogen gas in a mildly bubbling mode through a gas distributor and heating the substrate at temperatures around 1200.degree.-1500.degree. C. thereby depositing a layer of silicon carbide on the semiconductor substrate.

  19. Methods and devices for fabricating and assembling printable semiconductor elements

    DOE Patents [OSTI]

    Nuzzo, Ralph G; Rogers, John A; Menard, Etienne; Lee, Keon Jae; Khang, Dahl-Young; Sun, Yugang; Meitl, Matthew; Zhu, Zhengtao

    2013-05-14T23:59:59.000Z

    The invention provides methods and devices for fabricating printable semiconductor elements and assembling printable semiconductor elements onto substrate surfaces. Methods, devices and device components of the present invention are capable of generating a wide range of flexible electronic and optoelectronic devices and arrays of devices on substrates comprising polymeric materials. The present invention also provides stretchable semiconductor structures and stretchable electronic devices capable of good performance in stretched configurations.

  20. Methods and devices for fabricating and assembling printable semiconductor elements

    DOE Patents [OSTI]

    Nuzzo, Ralph G. (Champaign, IL); Rogers, John A. (Champaign, IL); Menard, Etienne (Durham, NC); Lee, Keon Jae (Daejeon, KR); Khang, Dahl-Young (Urbana, IL); Sun, Yugang (Champaign, IL); Meitl, Matthew (Raleigh, NC); Zhu, Zhengtao (Urbana, IL)

    2011-07-19T23:59:59.000Z

    The invention provides methods and devices for fabricating printable semiconductor elements and assembling printable semiconductor elements onto substrate surfaces. Methods, devices and device components of the present invention are capable of generating a wide range of flexible electronic and optoelectronic devices and arrays of devices on substrates comprising polymeric materials. The present invention also provides stretchable semiconductor structures and stretchable electronic devices capable of good performance in stretched configurations.

  1. Electron gas grid semiconductor radiation detectors

    DOE Patents [OSTI]

    Lee, Edwin Y. (Livermore, CA); James, Ralph B. (Livermore, CA)

    2002-01-01T23:59:59.000Z

    An electron gas grid semiconductor radiation detector (EGGSRAD) useful for gamma-ray and x-ray spectrometers and imaging systems is described. The radiation detector employs doping of the semiconductor and variation of the semiconductor detector material to form a two-dimensional electron gas, and to allow transistor action within the detector. This radiation detector provides superior energy resolution and radiation detection sensitivity over the conventional semiconductor radiation detector and the "electron-only" semiconductor radiation detectors which utilize a grid electrode near the anode. In a first embodiment, the EGGSRAD incorporates delta-doped layers adjacent the anode which produce an internal free electron grid well to which an external grid electrode can be attached. In a second embodiment, a quantum well is formed between two of the delta-doped layers, and the quantum well forms the internal free electron gas grid to which an external grid electrode can be attached. Two other embodiments which are similar to the first and second embodiment involve a graded bandgap formed by changing the composition of the semiconductor material near the first and last of the delta-doped layers to increase or decrease the conduction band energy adjacent to the delta-doped layers.

  2. Method for producing nanocrystalline multicomponent and multiphase materials

    DOE Patents [OSTI]

    Eastman, Jeffrey A. (Woodridge, IL); Rittner, Mindy N. (Des Plaines, IL); Youngdahl, Carl J. (Westmont, IL); Weertman, Julia R. (Evanston, IL)

    1998-01-01T23:59:59.000Z

    A process for producing multi-component and multiphase nanophase materials is provided wherein a plurality of elements are vaporized in a controlled atmosphere, so as to facilitate thorough mixing, and then condensing and consolidating the elements. The invention also provides for a multicomponent and multiphase nanocrystalline material of specified elemental and phase composition having component grain sizes of between approximately 1 nm and 100 nm. This material is a single element in combination with a binary compound. In more specific embodiments, the single element in this material can be a transition metal element, a non-transition metal element, a semiconductor, or a semi-metal, and the binary compound in this material can be an intermetallic, an oxide, a nitride, a hydride, a chloride, or other compound.

  3. Method for producing nanocrystalline multicomponent and multiphase materials

    DOE Patents [OSTI]

    Eastman, J.A.; Rittner, M.N.; Youngdahl, C.J.; Weertman, J.R.

    1998-03-17T23:59:59.000Z

    A process for producing multi-component and multiphase nanophase materials is provided wherein a plurality of elements are vaporized in a controlled atmosphere, so as to facilitate thorough mixing, and then condensing and consolidating the elements. The invention also provides for a multicomponent and multiphase nanocrystalline material of specified elemental and phase composition having component grain sizes of between approximately 1 nm and 100 nm. This material is a single element in combination with a binary compound. In more specific embodiments, the single element in this material can be a transition metal element, a non-transition metal element, a semiconductor, or a semi-metal, and the binary compound in this material can be an intermetallic, an oxide, a nitride, a hydride, a chloride, or other compound. 6 figs.

  4. Improving nickel metal hydride batteries through research in negative electrode corrosion control and novel electrode materials

    E-Print Network [OSTI]

    Alexander, Michael Scott

    1997-01-01T23:59:59.000Z

    The objective of this work is to improve the negative electrode of the metal hydride electrodes. Three areas were investigated: corrosion inhibition through Zn additives to the electrolyte, the use of AB5 and AB2 alloy mixtures, and novel AB2...

  5. DYNAMIC FAILURE OF METALLIC CELLULAR MATERIALS S. LEE and H.D. ESPINOSA

    E-Print Network [OSTI]

    Espinosa, Horacio D.

    interest in the protection design in automotive, locomotive, naval structures, and aerospace. Metallic not observe any rate dependency for the crashing stress of aluminum foams. These discrepancies from different within the specimen at very high strain rates. A model for shock waves in closed cell aluminum foams

  6. An Experimental Study of Deformation and Fracture of a Nanostructured Metallic Material 

    E-Print Network [OSTI]

    Abdel Al, Nisrin Rizek

    2011-02-22T23:59:59.000Z

    with the finest microstructure. They also point to the need for careful characterization of temperature effects before such materials can be considered in structural applications....

  7. Oxidation/corrosion of metallic and ceramic materials in an aluminum remelt furnace. [For fluidized bed waste heat recovery systems

    SciTech Connect (OSTI)

    Federer, J.I.; Jones, P.J.

    1985-12-01T23:59:59.000Z

    Both metallic alloys and ceramic materials are candidates for the distributor plate and other components of fluidized bed waste heat recovery (FBWHR) systems. Eleven Fe-, Ni-, and Co-base alloys were exposed to air at elevated temperatures in laboratory furnaces and to flue gases in an aluminum remelt furnace to assess their resistance to oxidation and corrosion. Four SiC ceramics and two oxide ceramics were also tested in the aluminum remelt furnace. Some alloys were coated with aluminum or SiO2 by commercial processes in an effort to enhance their oxidation and corrosion resistance.

  8. Hole mobility enhancements in strained SiSi1yGey p-type metal-oxide-semiconductor field-effect transistors grown on relaxed

    E-Print Network [OSTI]

    -effect transistors grown on relaxed Si1ÀxGex ,,xËy... virtual substrates C. W. Leitz,a) M. T. Currie, M. L. Lee, Z.-Y. Cheng, D. A. Antoniadis,b) and E. A. Fitzgerald Department of Materials Science and Engineering

  9. Introduction Creep is a time-dependent deformation that happens when metals or other materials are

    E-Print Network [OSTI]

    Cambridge, University of

    the yield strength as measured in a tensile test, and yet, creep causes permanent deformation. Materials deformation and creep test have been reviewed in a number of excellent publications [5]. The plastic strain. If the material has been heavily worked before the creep test, there would be many more dislocations present

  10. Nonlocal study of the near field radiative heat transfer between two n-doped semiconductors

    E-Print Network [OSTI]

    Singer, F; Joulain, Karl

    2015-01-01T23:59:59.000Z

    We study in this work the near-field radiative heat transfer between two semi-infinite parallel planes of highly n-doped semiconductors. Using a nonlocal model of the dielectric permittivity, usually used for the case of metallic planes, we show that the radiative heat transfer coefficientsaturates as the separation distance is reduced for high doping concentration. These results replace the 1/d${}^2$ infinite divergence obtained in the local model case. Different features of the obtained results are shown to relate physically to the parameters of the materials, mainly the doping concentration and the plasmon frequency.

  11. Comparison of Wide-Bandgap Semiconductors for Power Electronics Applications

    SciTech Connect (OSTI)

    Ozpineci, B.

    2004-01-02T23:59:59.000Z

    Recent developmental advances have allowed silicon (Si) semiconductor technology to approach the theoretical limits of the Si material; however, power device requirements for many applications are at a point that the present Si-based power devices cannot handle. The requirements include higher blocking voltages, switching frequencies, efficiency, and reliability. To overcome these limitations, new semiconductor materials for power device applications are needed. For high power requirements, wide-bandgap semiconductors like silicon carbide (SiC), gallium nitride (GaN), and diamond, with their superior electrical properties, are likely candidates to replace Si in the near future. This report compares wide-bandgap semiconductors with respect to their promise and applicability for power applications and predicts the future of power device semiconductor materials.

  12. Dry etching method for compound semiconductors

    DOE Patents [OSTI]

    Shul, R.J.; Constantine, C.

    1997-04-29T23:59:59.000Z

    A dry etching method is disclosed. According to the present invention, a gaseous plasma comprising, at least in part, boron trichloride, methane, and hydrogen may be used for dry etching of a compound semiconductor material containing layers including aluminum, or indium, or both. Material layers of a compound semiconductor alloy such as AlGaInP or the like may be anisotropically etched for forming electronic devices including field-effect transistors and heterojunction bipolar transistors and for forming photonic devices including vertical-cavity surface-emitting lasers, edge-emitting lasers, and reflectance modulators. 1 fig.

  13. Dry etching method for compound semiconductors

    DOE Patents [OSTI]

    Shul, Randy J. (Albuquerque, NM); Constantine, Christopher (Safety Harbor, FL)

    1997-01-01T23:59:59.000Z

    A dry etching method. According to the present invention, a gaseous plasma comprising, at least in part, boron trichloride, methane, and hydrogen may be used for dry etching of a compound semiconductor material containing layers including aluminum, or indium, or both. Material layers of a compound semiconductor alloy such as AlGaInP or the like may be anisotropically etched for forming electronic devices including field-effect transistors and heterojunction bipolar transistors and for forming photonic devices including vertical-cavity surface-emitting lasers, edge-emitting lasers, and reflectance modulators.

  14. Interconnected semiconductor devices

    DOE Patents [OSTI]

    Grimmer, Derrick P. (White Bear Lake, MN); Paulson, Kenneth R. (North St. Paul, MN); Gilbert, James R. (St. Paul, MN)

    1990-10-23T23:59:59.000Z

    Semiconductor layer and conductive layer formed on a flexible substrate, divided into individual devices and interconnected with one another in series by interconnection layers and penetrating terminals.

  15. Method for separating metal chelates from other materials based on solubilities in supercritical fluids

    DOE Patents [OSTI]

    Wai, Chien M. (Moscow, ID); Smart, Neil G. (Workington, GB); Phelps, Cindy (Moscow, ID)

    2001-01-01T23:59:59.000Z

    A method for separating a desired metal or metalloi from impurities using a supercritical extraction process based on solubility differences between the components, as well as the ability to vary the solvent power of the supercritical fluid, is described. The use of adduct-forming agents, such as phosphorous-containing ligands, to separate metal or metalloid chelates in such processes is further disclosed. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is selected from the group consisting of .beta.-diketones; phosphine oxides, such as trialkylphosphine oxides, triarylphosphine oxides and alkylarylphosphine oxides; phosphinic acids; carboxylic acids; phosphates, such as trialkylphosphates, triarylphosphates and alkylarylphosphates; crown ethers; dithiocarbamates; phosphine sulfides; phosphorothioic acids; thiophosphinic acids; halogenated analogs of these chelating agents; and mixtures of these chelating agents. In especially preferred embodiments, at least one of the chelating agents is fluorinated.

  16. Removal of radioactive materials and heavy metals from water using magnetic resin

    DOE Patents [OSTI]

    Kochen, Robert L. (Boulder, CO); Navratil, James D. (Simi Valley, CA)

    1997-01-21T23:59:59.000Z

    Magnetic polymer resins capable of efficient removal of actinides and heavy metals from contaminated water are disclosed together with methods for making, using, and regenerating them. The resins comprise polyamine-epichlorohydrin resin beads with ferrites attached to the surfaces of the beads. Markedly improved water decontamination is demonstrated using these magnetic polymer resins of the invention in the presence of a magnetic field, as compared with water decontamination methods employing ordinary ion exchange resins or ferrites taken separately.

  17. Removal of radioactive materials and heavy metals from water using magnetic resin

    DOE Patents [OSTI]

    Kochen, R.L.; Navratil, J.D.

    1997-01-21T23:59:59.000Z

    Magnetic polymer resins capable of efficient removal of actinides and heavy metals from contaminated water are disclosed together with methods for making, using, and regenerating them. The resins comprise polyamine-epichlorohydrin resin beads with ferrites attached to the surfaces of the beads. Markedly improved water decontamination is demonstrated using these magnetic polymer resins of the invention in the presence of a magnetic field, as compared with water decontamination methods employing ordinary ion exchange resins or ferrites taken separately. 9 figs.

  18. Immobilization of vanadia deposited on catalytic materials during carbo-metallic oil conversion

    SciTech Connect (OSTI)

    Beck, H.W.; Carruthers, J.D.; Cornelius, E.B.; Hettinger, Jr., W.P.; Kovach, S.M.; Palmer, J.L.; Zandona, O.J.

    1988-06-14T23:59:59.000Z

    This patent describes a process for the cracking of a hydrocarbon oil feed having a significant content of at least 0.1 ppm vanadium to lighter oil products. The process consists of contacting the feed under conversion conditions in a conversion zone with a catalyst containing a precipitated metal additive to immobilize vanadium compounds by forming compounds therewith that have melting points above temperatures found in regenerating a coked catalyst; and having catalytic cracking characteristics, coke and vanadium being deposited on the catalyst by the contact; regenerating the coked catalyst in the presence of an oxygen containing gas at a temperature sufficient to remove at least some of the coke, and, recycling the regenerated catalyst to the conversion zone for contact with fresh feed; the metal additive being present on the catalyst in an amount sufficient to immobilize at least a portion of the vanadium compound in the presence of the oxygen containing gas at the catalyst regeneration temperature; wherein the metal additive to immobilize vanadium compounds deposited on the catalyst is selected from the group consisting of Sr, Sc, Y, Nb, and Ta elements, and an element in the actinide series, or a combination of two or more of the elements.

  19. Grain-boundary engineering markedly reduces susceptibility to intergranular hydrogen embrittlement in metallic materials

    E-Print Network [OSTI]

    Ritchie, Robert

    Grain-boundary engineering markedly reduces susceptibility to intergranular hydrogen embrittlement. Keywords: Hydrogen embrittlement; Intergranular cracking; Grain-boundary engineering; Special boundaries,e,* a Department of Materials Science and Engineering, University of California, Berkeley, CA 94720, USA b

  20. STRAIN RATE EFFECTS IN METALLIC CELLULAR MATERIALS Sungsoo Lee, Francois Barthelat and Horacio D. Espinosa

    E-Print Network [OSTI]

    Espinosa, Horacio D.

    absorption of aluminium alloy foams [2-4]. However no quantitative result was reported about the different on the aluminium foam and on the stainless steel truss core material under quasi- static and dynamic loadings. Fig

  1. Optical amplifier operating at 1.3 microns useful for telecommunications and based on dysprosium-doped metal chloride host materials

    DOE Patents [OSTI]

    Page, R.H.; Schaffers, K.I.; Payne, S.A.; Krupke, W.F.; Beach, R.J.

    1997-12-02T23:59:59.000Z

    Dysprosium-doped metal chloride materials offer laser properties advantageous for use as optical amplifiers in the 1.3 {micro}m telecommunications fiber optic network. The upper laser level is characterized by a millisecond lifetime, the host material possesses a moderately low refractive index, and the gain peak occurs near 1.31 {micro}m. Related halide materials, including bromides and iodides, are also useful. The Dy{sup 3+}-doped metal chlorides can be pumped with laser diodes and yield 1.3 {micro}m signal gain levels significantly beyond those currently available. 9 figs.

  2. Optical amplifier operating at 1.3 microns useful for telecommunications and based on dysprosium-doped metal chloride host materials

    DOE Patents [OSTI]

    Page, Ralph H. (San Ramon, CA); Schaffers, Kathleen I. (Pleasanton, CA); Payne, Stephen A. (Castro Valley, CA); Krupke, William F. (Pleasanton, CA); Beach, Raymond J. (Livermore, CA)

    1997-01-01T23:59:59.000Z

    Dysprosium-doped metal chloride materials offer laser properties advantageous for use as optical amplifiers in the 1.3 .mu.m telecommunications fiber optic network. The upper laser level is characterized by a millisecond lifetime, the host material possesses a moderately low refractive index, and the gain peak occurs near 1.31 .mu.m. Related halide materials, including bromides and iodides, are also useful. The Dy.sup.3+ -doped metal chlorides can be pumped with laser diodes and yield 1.3 .mu.m signal gain levels significantly beyond those currently available.

  3. Organo luminescent semiconductor nanocrystal probes for biological applications and process for making and using such probes

    DOE Patents [OSTI]

    Weiss, Shimon (Pinole, CA); Bruchez, Jr., Marcel (Albany, CA); Alivisatos, Paul (Oakland, CA)

    2008-01-01T23:59:59.000Z

    A semiconductor nanocrystal compound is described capable of linking to an affinity molecule. The compound comprises (1) a semiconductor nanocrystal capable of emitting electromagnetic radiation and/or absorbing energy, and/or scattering or diffracting electromagnetic radiation--when excited by an electromagnetic radiation source or a particle beam; and (2) an affinity molecule linked to the semiconductor nanocrystal. The semiconductor nanocrystal is linked to an affinity molecule to form a semiconductor nanocrystal probe capable of bonding with a detectable substance. Exposure of the semiconductor nanocrystal to excitation energy will excite the semiconductor nanocrystal causing the emission of electromagnetic radiation. Further described are processes for respectively: making the luminescent semiconductor nanocrystal compound; making the semiconductor nanocrystal probe; and using the probe to determine the presence of a detectable substance in a material.

  4. Band gap engineering at a semiconductor - crystalline oxide interface

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Moghadam, Jahangir-Moghadam; Shen, Xuan; Chrysler, Matthew; Ahmadi-Majlan, Kamyar; Su, Dong; Ngai, Joseph H.

    2015-03-01T23:59:59.000Z

    The epitaxial growth of crystalline oxides on semiconductors provides a pathway to introduce new functionalities to semiconductor devices. Key to integrating the functionalities of oxides onto semiconductors is controlling the band alignment at interfaces between the two materials. Here we apply principles of band gap engineering traditionally used at heterojunctions between conventional semiconductors to control the band offset between a single crystalline oxide and a semiconductor. Reactive molecular beam epitaxy is used to realize atomically abrupt and structurally coherent interfaces between SrZrxTi1-xO? and Ge, in which the band gap of the former is enhanced with Zr content x. We presentmore »structural and electrical characterization of SrZrxTi1-xO?-Ge heterojunctions and demonstrate a type-I band offset can be achieved. These results demonstrate that band gap engineering can be exploited to realize functional semiconductor crystalline oxide heterojunctions.« less

  5. Strength of semiconductors, metals, and ceramics evaluated by a microscopic cleavage model with Morse-type and Lennard-Jones-type interaction

    SciTech Connect (OSTI)

    Hess, Peter [Institute of Physical Chemistry, University of Heidelberg, Im Neuenheimer Feld 253, D-69120 Heidelberg (Germany)

    2014-08-07T23:59:59.000Z

    An improved microscopic cleavage model, based on a Morse-type and Lennard-Jones-type interaction instead of the previously employed half-sine function, is used to determine the maximum cleavage strength for the brittle materials diamond, tungsten, molybdenum, silicon, GaAs, silica, and graphite. The results of both interaction potentials are in much better agreement with the theoretical strength values obtained by ab initio calculations for diamond, tungsten, molybdenum, and silicon than the previous model. Reasonable estimates of the intrinsic strength are presented for GaAs, silica, and graphite, where first principles values are not available.

  6. Spintronics and Nanomagnetics Nate Newman

    E-Print Network [OSTI]

    Zhang, Junshan

    magnetic semiconductor materials Approach Synthesize semiconductors doped w/ transition-metals to create

  7. Wide-Bandgap Semiconductors

    SciTech Connect (OSTI)

    Chinthavali, M.S.

    2005-11-22T23:59:59.000Z

    With the increase in demand for more efficient, higher-power, and higher-temperature operation of power converters, design engineers face the challenge of increasing the efficiency and power density of converters [1, 2]. Development in power semiconductors is vital for achieving the design goals set by the industry. Silicon (Si) power devices have reached their theoretical limits in terms of higher-temperature and higher-power operation by virtue of the physical properties of the material. To overcome these limitations, research has focused on wide-bandgap materials such as silicon carbide (SiC), gallium nitride (GaN), and diamond because of their superior material advantages such as large bandgap, high thermal conductivity, and high critical breakdown field strength. Diamond is the ultimate material for power devices because of its greater than tenfold improvement in electrical properties compared with silicon; however, it is more suited for higher-voltage (grid level) higher-power applications based on the intrinsic properties of the material [3]. GaN and SiC power devices have similar performance improvements over Si power devices. GaN performs only slightly better than SiC. Both SiC and GaN have processing issues that need to be resolved before they can seriously challenge Si power devices; however, SiC is at a more technically advanced stage than GaN. SiC is considered to be the best transition material for future power devices before high-power diamond device technology matures. Since SiC power devices have lower losses than Si devices, SiC-based power converters are more efficient. With the high-temperature operation capability of SiC, thermal management requirements are reduced; therefore, a smaller heat sink would be sufficient. In addition, since SiC power devices can be switched at higher frequencies, smaller passive components are required in power converters. Smaller heat sinks and passive components result in higher-power-density power converters. With the advent of the use of SiC devices it is imperative that models of these be made available in commercial simulators. This enables power electronic designers to simulate their designs for various test conditions prior to fabrication. To build an accurate transistor-level model of a power electronic system such as an inverter, the first step is to characterize the semiconductor devices that are present in the system. Suitable test beds need to be built for each device to precisely test the devices and obtain relevant data that can be used for modeling. This includes careful characterization of the parasitic elements so as to emulate the test setup as closely as possible in simulations. This report is arranged as follows: Chapter 2--The testing and characterization of several diodes and power switches is presented. Chapter 3--A 55-kW hybrid inverter (Si insulated gate bipolar transistor--SiC Schottky diodes) device models and test results are presented. A detailed description of the various test setups followed by the parameter extraction, modeling, and simulation study of the inverter performance is presented. Chapter 4--A 7.5-kW all-SiC inverter (SiC junction field effect transistors (JFET)--SiC Schottky diodes) was built and tested. The models built in Saber were validated using the test data and the models were used in system applications in the Saber simulator. The simulation results and a comparison of the data from the prototype tests are discussed in this chapter. Chapter 5--The duration test results of devices utilized in buck converters undergoing reliability testing are presented.

  8. 2 www.trnmag.com Technology Research News February 23/March 2, 2005 Process yields semiconductor foam

    E-Print Network [OSTI]

    Ruina, Andy L.

    Wayne State University have made crystalline aerogels -- new semiconductor materials that are very porous, giving them very high surface areas. Unlike conventional aerogels, the researchers' materials

  9. Self-assembled photosynthesis-inspired light harvesting material and solar cells containing the same

    DOE Patents [OSTI]

    Lindsey, Jonathan S. (Raleigh, NC); Chinnasamy, Muthiah (Raleigh, NC); Fan, Dazhong (Raleigh, NC)

    2009-12-15T23:59:59.000Z

    A solar cell is described that comprises: (a) a semiconductor charge separation material; (b) at least one electrode connected to the charge separation material; and (c) a light-harvesting film on the charge separation material, the light-harvesting film comprising non-covalently coupled, self-assembled units of porphyrinic macrocycles. The porphyrinic macrocycles preferably comprise: (i) an intramolecularly coordinated metal; (ii) a first coordinating substituent; and (iii) a second coordinating substituent opposite the first coordinating substituent. The porphyrinic macrocycles can be assembled by repeating intermolecular coordination complexes of the metal, the first coordinating substituent and the second coordinating substituent.

  10. Final Technical Report on DE-SC00002460 [Bimetallic or trimetallic materials with structural metal centers based on Mn, Fe or V

    SciTech Connect (OSTI)

    Takeuchi, Esther Sans [Stony Brook University; Takeuchi, Kenneth James [Stony Brook University; Marschilok, Amy Catherine [Stony Brook University

    2013-07-26T23:59:59.000Z

    Bimetallic or trimetallic materials with structural metal centers based on Mn, Fe or V were investigated under this project. These metal centers are the focus of this research as they have high earth abundance and have each shown success as cathode materials in lithium batteries. Silver ion, Ag{sup +}, was initially selected as the displacement material as reduction of this center should result in increased conductivity as Ag{sup 0} metal particles are formed in-situ upon electrochemical reduction. The in-situ formation of metal nanoparticles upon electrochemical reduction has been previously noted, and more recently, we have investigated the resulting increase in conductivity. Layered materials as well as materials with tunnel or channel type structures were selected. Layered materials are of interest as they can provide 2-dimensional ion mobility. Tunnel or channel structures are also of interest as they provide a rigid framework that should remain stable over many discharge/charge cycles. We describe some examples of materials we have synthesized that demonstrate promising electrochemistry.

  11. Low interface defect density of atomic layer deposition BeO with self-cleaning reaction for InGaAs metal oxide semiconductor field effect transistors

    SciTech Connect (OSTI)

    Shin, H. S. [Department of Electronics Engineering, Chungnam National University, Daejeon (Korea, Republic of) [Department of Electronics Engineering, Chungnam National University, Daejeon (Korea, Republic of); SEMATECH, 2706 Montopolis Dr., Austin, Texas 78741 (United States); The University of Texas, Austin, Texas 78758 (United States); Yum, J. H. [SEMATECH, 2706 Montopolis Dr., Austin, Texas 78741 (United States) [SEMATECH, 2706 Montopolis Dr., Austin, Texas 78741 (United States); The University of Texas, Austin, Texas 78758 (United States); Johnson, D. W. [SEMATECH, 2706 Montopolis Dr., Austin, Texas 78741 (United States) [SEMATECH, 2706 Montopolis Dr., Austin, Texas 78741 (United States); Texas A and M University College Station, Texas 77843 (United States); Harris, H. R. [Texas A and M University College Station, Texas 77843 (United States)] [Texas A and M University College Station, Texas 77843 (United States); Hudnall, Todd W. [Texas State University, 601 University Drive, San Marcos, Texas 78666 (United States)] [Texas State University, 601 University Drive, San Marcos, Texas 78666 (United States); Oh, J. [Yonsei University, Incheon, 406-840 (Korea, Republic of)] [Yonsei University, Incheon, 406-840 (Korea, Republic of); Kirsch, P.; Wang, W.-E. [SEMATECH, 2706 Montopolis Dr., Austin, Texas 78741 (United States)] [SEMATECH, 2706 Montopolis Dr., Austin, Texas 78741 (United States); Bielawski, C. W.; Banerjee, S. K.; Lee, J. C. [The University of Texas, Austin, Texas 78758 (United States)] [The University of Texas, Austin, Texas 78758 (United States); Lee, H. D. [Department of Electronics Engineering, Chungnam National University, Daejeon (Korea, Republic of)] [Department of Electronics Engineering, Chungnam National University, Daejeon (Korea, Republic of)

    2013-11-25T23:59:59.000Z

    In this paper, we discuss atomic configuration of atomic layer deposition (ALD) beryllium oxide (BeO) using the quantum chemistry to understand the theoretical origin. BeO has shorter bond length, higher reaction enthalpy, and larger bandgap energy compared with those of ALD aluminum oxide. It is shown that the excellent material properties of ALD BeO can reduce interface defect density due to the self-cleaning reaction and this contributes to the improvement of device performance of InGaAs MOSFETs. The low interface defect density and low leakage current of InGaAs MOSFET were demonstrated using X-ray photoelectron spectroscopy and the corresponding electrical results.

  12. Final Report Theoretical Studies of Surface Reactions on Metals and Electronic Materials

    SciTech Connect (OSTI)

    Jerry L. Whitten

    2012-04-23T23:59:59.000Z

    This proposal describes the proposed renewal of a theoretical research program on the structure and reactivity of molecules adsorbed on transition metal surfaces. A new direction of the work extends investigations to interfaces between solid surfaces, adsorbates and aqueous solutions and includes fundamental work on photoinduced electron transport into chemisorbed species and into solution. The goal is to discover practical ways to reduce water to hydrogen and oxygen using radiation comparable to that available in the solar spectrum. The work relates to two broad subject areas: photocatalytic processes and production of hydrogen from water. The objective is to obtain high quality solutions of the electronic structure of adsorbate-metal-surface-solution systems so as to allow activation barriers to be calculated and reaction mechanisms to be determined. An ab initio embedding formalism provides a route to the required accuracy. New theoretical methods developed during the previous grant period will be implemented in order to solve the large systems involved in this work. Included is the formulation of a correlation operator that is used to treat localized electron distributions such as ionic or regionally localized distributions. The correlation operator which is expressed as a two-particle projector is used in conjunction with configuration interaction.

  13. Deactivation Mechanisms of Base Metal/Zeolite Urea Selective Catalytic Reduction Materials, and Development of Zeolite-Based Hydrocarbon Adsorber Materials

    SciTech Connect (OSTI)

    Gao, Feng; Kwak, Ja Hun; Lee, Jong H.; Tran, Diana N.; Peden, Charles HF; Howden, Ken; Cheng, Yisun; Lupescu, Jason; Cavattaio, Giovanni; Lambert, Christine; McCabe, Robert W.

    2012-12-31T23:59:59.000Z

    In this collaborative program, scientists and engineers in the Institute for Integrated Catalysis at Pacific Northwest National Laboratory and at Ford Motor Company have investigated laboratory- and engine-aged SCR catalysts, containing mainly base metal zeolites. These studies are leading to a better understanding of various aging factors that impact the long-term performance of SCR catalysts and improve the correlation between laboratory and engine aging, saving experimental time and cost. We have also studied materials effective for the temporary storage of HC species during the cold-start period. In particular, we have examined the adsorption and desorption of various HC species produced during the combustion with different fuels (e.g., gasoline, E85, diesel) over potential HC adsorber materials, and measured the kinetic parameters to update Ford’s HC adsorption model. Since this CRADA has now been completed, in this annual report we will provide very brief summaries of most of the work carried out on this CRADA over the last several years.

  14. Conductive layer for biaxially oriented semiconductor film growth

    DOE Patents [OSTI]

    Findikoglu, Alp T. (Los Alamos, NM); Matias, Vladimir (Santa Fe, NM)

    2007-10-30T23:59:59.000Z

    A conductive layer for biaxially oriented semiconductor film growth and a thin film semiconductor structure such as, for example, a photodetector, a photovoltaic cell, or a light emitting diode (LED) that includes a crystallographically oriented semiconducting film disposed on the conductive layer. The thin film semiconductor structure includes: a substrate; a first electrode deposited on the substrate; and a semiconducting layer epitaxially deposited on the first electrode. The first electrode includes a template layer deposited on the substrate and a buffer layer epitaxially deposited on the template layer. The template layer includes a first metal nitride that is electrically conductive and has a rock salt crystal structure, and the buffer layer includes a second metal nitride that is electrically conductive. The semiconducting layer is epitaxially deposited on the buffer layer. A method of making such a thin film semiconductor structure is also described.

  15. Features of the electric-field distribution in anisotropic semiconductor wafers in a transverse magnetic field

    SciTech Connect (OSTI)

    Filippov, V. V., E-mail: wwfilippow@mail.ru [Lipetsk State Pedagogical University (Russian Federation); Bormontov, E. N. [Voronezh State University (Russian Federation)

    2013-07-15T23:59:59.000Z

    A macroscopic model of the Hall effects and magnetoresistance in anisotropic semiconductor wafers is developed. The results obtained by solving the electrodynamic boundary problem allow the potential and eddy currents in anisotropic semiconductors to be calculated at different current-contact locations, depending on the parameters of the sample material's anisotropy. The results of this study are of great practical importance for investigating the physical properties of anisotropic semiconductors and simulating the electron-transport phenomena in devices based on anisotropic semiconductors.

  16. Compatibility Study for Plastic, Elastomeric, and Metallic Fueling Infrastructure Materials Exposed to Aggressive Formulations of Ethanol-blended Gasoline

    SciTech Connect (OSTI)

    Kass, Michael D [ORNL; Pawel, Steven J [ORNL; Theiss, Timothy J [ORNL; Janke, Christopher James [ORNL

    2012-07-01T23:59:59.000Z

    In 2008 Oak Ridge National Laboratory began a series of experiments to evaluate the compatibility of fueling infrastructure materials with intermediate levels of ethanol-blended gasoline. Initially, the focus was elastomers, metals, and sealants, and the test fuels were Fuel C, CE10a, CE17a and CE25a. The results of these studies were published in 2010. Follow-on studies were performed with an emphasis on plastic (thermoplastic and thermoset) materials used in underground storage and dispenser systems. These materials were exposed to test fuels of Fuel C and CE25a. Upon completion of this effort, it was felt that additional compatibility data with higher ethanol blends was needed and another round of experimentation was performed on elastomers, metals, and plastics with CE50a and CE85a test fuels. Compatibility of polymers typically relates to the solubility of the solid polymer with a solvent. It can also mean susceptibility to chemical attack, but the polymers and test fuels evaluated in this study are not considered to be chemically reactive with each other. Solubility in polymers is typically assessed by measuring the volume swell of the polymer exposed to the solvent of interest. Elastomers are a class of polymers that are predominantly used as seals, and most o-ring and seal manufacturers provide compatibility tables of their products with various solvents including ethanol, toluene, and isooctane, which are components of aggressive oxygenated gasoline as described by the Society of Automotive Engineers (SAE) J1681. These tables include a ranking based on the level of volume swell in the elastomer associated with exposure to a particular solvent. Swell is usually accompanied by a decrease in hardness (softening) that also affects performance. For seal applications, shrinkage of the elastomer upon drying is also a critical parameter since a contraction of volume can conceivably enable leakage to occur. Shrinkage is also indicative of the removal of one or more components of the elastomers (by the solvent). This extraction of additives can negatively change the properties of the elastomer, leading to reduced performance and durability. For a seal application, some level of volume swell is acceptable, since the expansion will serve to maintain a seal. However, the acceptable level of swell is dependent on the particular application of the elastomer product. It is known that excessive swell can lead to unacceptable extrusion of the elastomer beyond the sealed interface, where it becomes susceptible to damage. Also, since high swell is indicative of high solubility, there is a heightened potential for fluid to seep through the seal and into the environment. Plastics, on the other hand, are used primarily in structural applications, such as solid components, including piping and fluid containment. Volume change, especially in a rigid system, will create internal stresses that may negatively affect performance. In order to better understand and predict the compatibility for a given polymer type and fuel composition, an analysis based on Hansen solubility theory was performed for each plastic and elastomer material. From this study, the solubility distance was calculated for each polymer material and test fuel combination. Using the calculated solubility distance, the ethanol concentration associated with peak swell and overall extent of swell can be predicted for each polymer. The bulk of the material discussion centers on the plastic materials, and their compatibility with Fuel C, CE25a, CE50a, and CE85a. The next section of this paper focuses on the elastomer compatibility with the higher ethanol concentrations with comparison to results obtained previously for the lower ethanol levels. The elastomers were identical to those used in the earlier study. Hansen solubility theory is also applied to the elastomers to provide added interpretation of the results. The final section summarizes the performance of the metal coupons.

  17. MCWASP, Modeling of Casting, Welding and Advanced Solidification Processes XI TMS (The Minerals, Metals & Materials Society),

    E-Print Network [OSTI]

    Zabaras, Nicholas J.

    -COMPONENT ALLOYS USING LEVEL SET METHODS Nicholas Zabaras1 , Lijian Tan1 1 Materials Process Design and Control Laboratory 188 Frank H.T Rhodes Hall, Sibley school of Mechanical and Aerospace Engineering, Cornell, Multi-component alloy, Multi-phase, Fluid flow. Abstract A level set method combining features of front

  18. Iron-Based Amorphous-Metals: High-Performance Corrosion-Resistant Materials (HPCRM) Development Final Report

    SciTech Connect (OSTI)

    Farmer, J C; Choi, J; Saw, C; Haslem, J; Day, D; Hailey, P; Lian, T; Rebak, R; Perepezko, J; Payer, J; Branagan, D; Beardsley, B; D'Amato, A; Aprigliano, L

    2009-03-16T23:59:59.000Z

    An overview of the High-Performance Corrosion-Resistant Materials (HPCRM) Program, which was co-sponsored by the Defense Advanced Research Projects Agency (DARPA) Defense Sciences Office (DSO) and the United States Department of Energy (DOE) Office of Civilian and Radioactive Waste Management (OCRWM), is discussed. Programmatic investigations have included a broad range of topics: alloy design and composition; materials synthesis; thermal stability; corrosion resistance; environmental cracking; mechanical properties; damage tolerance; radiation effects; and important potential applications. Amorphous alloys identified as SAM2X5 (Fe{sub 49.7}Cr{sub 17.7}Mn{sub 1.9}Mo{sub 7.4}W{sub 1.6}B{sub 15.2}C{sub 3.8}Si{sub 2.4}) and SAM1651 (Fe{sub 48}Mo{sub 14}Cr{sub 15}Y{sub 2}C{sub 15}B{sub 6}) have been produced as melt-spun ribbons, drop-cast ingots and thermal-spray coatings. Chromium (Cr), molybdenum (Mo) and tungsten (W) additions provided corrosion resistance, while boron (B) enabled glass formation. Earlier electrochemical studies of melt-spun ribbons and ingots of these amorphous alloys demonstrated outstanding passive film stability. More recently thermal-spray coatings of these amorphous alloys have been made and subjected to long-term salt-fog and immersion tests. Good corrosion resistance has been observed during salt-fog testing. Corrosion rates were measured in situ with linear polarization, while simultaneously monitoring the open-circuit corrosion potentials. Reasonably good performance was observed. The sensitivity of these measurements to electrolyte composition and temperature was determined. The high boron content of this particular amorphous metal make this amorphous alloy an effective neutron absorber, and suitable for criticality control applications. In general, the corrosion resistance of these iron-based amorphous metals is maintained at operating temperatures up to the glass transition temperature. These materials are much harder than conventional stainless steel and nickel-based materials, and are proving to have excellent wear properties, sufficient to warrant their use in earth excavation, drilling and tunnel boring applications. The observed corrosion resistance may enable applications of importance in industries such as: oil and gas production, refining, nuclear power generation, shipping, and others. Large areas have been successfully coated with these materials, with thicknesses of approximately one centimeter.

  19. Exploring and enhancing conductivity in semiconductor nanoparticle films

    E-Print Network [OSTI]

    Porter, Venda Jane

    2007-01-01T23:59:59.000Z

    Semiconductor nanocrystals (NCs) are a promising material for use in opto-electronic devices as their optical properties tune with particle size. NCs formed via colloidal synthesis are suspended in solution by the organic ...

  20. Method and apparatus for use of III-nitride wide bandgap semiconductors in optical communications

    DOE Patents [OSTI]

    Hui, Rongqing (Lenexa, KS); Jiang,Hong-Xing (Manhattan, KS); Lin, Jing-Yu (Manhattan, KS)

    2008-03-18T23:59:59.000Z

    The present disclosure relates to the use of III-nitride wide bandgap semiconductor materials for optical communications. In one embodiment, an optical device includes an optical waveguide device fabricated using a III-nitride semiconductor material. The III-nitride semiconductor material provides for an electrically controllable refractive index. The optical waveguide device provides for high speed optical communications in an infrared wavelength region. In one embodiment, an optical amplifier is provided using optical coatings at the facet ends of a waveguide formed of erbium-doped III-nitride semiconductor materials.

  1. Use of impure inert gases in the controlled heating and cooling of mixed conducting metal oxide materials

    DOE Patents [OSTI]

    Carolan, Michael Francis (Allentown, PA); Bernhart, John Charles (Fleetwood, PA)

    2012-08-21T23:59:59.000Z

    Method for processing an article comprising mixed conducting metal oxide material. The method comprises contacting the article with an oxygen-containing gas and either reducing the temperature of the oxygen-containing gas during a cooling period or increasing the temperature of the oxygen-containing gas during a heating period; during the cooling period, reducing the oxygen activity in the oxygen-containing gas during at least a portion of the cooling period and increasing the rate at which the temperature of the oxygen-containing gas is reduced during at least a portion of the cooling period; and during the heating period, increasing the oxygen activity in the oxygen-containing gas during at least a portion of the heating period and decreasing the rate at which the temperature of the oxygen-containing gas is increased during at least a portion of the heating period.

  2. Long-Term Materials Test program. Quarterly report, January-March 1984. [Metal aluminide and MCrAlY coatings

    SciTech Connect (OSTI)

    Not Available

    1984-01-01T23:59:59.000Z

    Corrosion and erosion/corrosion testing of gas turbine vane and blade base alloys and a variety of protective coating systems under the Long-Term Materials Test program has surpassed 5574 hours. The Pressurized Fluidized Bed Combustion (PFBC) facility at Malta, New York continues to show an exceptionally high degree of reliability and consistency in performance. Operating conditions include a 1650/sup 0/F bed temperature at 10 atmospheres pressure utilizing Pittsburgh No. 8 coal and a low alkali dolomite sulfur sorbent. After 2687 hours, unprotected nickel and cobalt base vane and blade alloys generally experienced corrosion rates of 1 to 2 mils/1000 hours at metal temperatures of 1100/sup 0/, 1300/sup 0/ and 1500/sup 0/F. Precious metal aluminide and MCrAlY coatings continue to show excellent corrosion resistance (<0.5 mils/1000 hrs) at 1500/sup 0/F, but are susceptible to varying degrees of pitting attack at 1100/sup 0/ and 1300/sup 0/F. Erosion/corrosion degradation rates at 800 to 900 ft/s, 1350/sup 0/F and less than 100 ppM dust loading ranged from 1 to 4 mils/1000 h with corrosion predominately concentrated in areas of particle impaction indicating an erosion/corrosion synergism. 6 figures, 3 tables.

  3. Carrier-lifetime-controlled selective etching process for semiconductors using photochemical etching

    DOE Patents [OSTI]

    Ashby, Carol I. H. (Edgewood, NM); Myers, David R. (Albuquerque, NM)

    1992-01-01T23:59:59.000Z

    The minority carrier lifetime is significantly much shorter in semiconductor materials with very high impurity concentrations than it is in semiconductor materials with lower impurity concentration levels. This phenomenon of reduced minority carrier lifetime in semiconductor materials having high impurity concentration is utilized to advantage for permitting highly selective semiconductor material etching to be achieved using a carrier-driven photochemical etching reaction. Various means may be employed for increasing the local impurity concentration level in specific near-surface regions of a semiconductor prior to subjecting the semiconductor material to a carrier-driven photochemical etching reaction. The regions having the localized increased impurity concentration form a self-aligned mask inhibiting photochemical etching at such localized regions while the adjacent regions not having increased impurity concentrations are selectively photochemically etched. Liquid- or gas-phase etching may be performed.

  4. Synthesis and Characterization of Mesoporous Semiconductors and Their Energy Applications

    E-Print Network [OSTI]

    Kang, Chris Byung-hwa

    2013-01-01T23:59:59.000Z

    of high purity silicon. Rare earth metals on the other hand,of the material functions of rare earth metals in electronic

  5. New Materials for Spintronics. | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Abstract: One of the critical materials needs for the development of spin electronics is diluted magnetic semiconductors (DMS) which retain their ferromagnetism at and...

  6. Metal Hydrides - Science Needs

    Broader source: Energy.gov (indexed) [DOE]

    with traditions in metal hydride research Metal and Ceramic Sciences Condensed Matter Physics Materials Chemistry Chemical and Biological Sciences Located on campus of Tier...

  7. Process for carbonaceous material conversion and recovery of alkali metal catalyst constituents held by ion exchange sites in conversion residue

    DOE Patents [OSTI]

    Sharp, David W. (Seabrook, TX)

    1980-01-01T23:59:59.000Z

    In a coal gasification operation or similar conversion process carried out in the presence of an alkali metal-containing catalyst wherein solid particles containing alkali metal residues are produced, alkali metal constituents are recovered for the particles by contacting or washing them with an aqueous solution containing calcium or magnesium ions in an alkali metal recovery zone at a low temperature, preferably below about 249.degree. F. During the washing or leaching process, the calcium or magnesium ions displace alkali metal ions held by ion exchange sites in the particles thereby liberating the ions and producing an aqueous effluent containing alkali metal constituents. The aqueous effluent from the alkali metal recovery zone is then recycled to the conversion process where the alkali metal constituents serve as at least a portion of the alkali metal constituents which comprise the alkali metal-containing catalyst.

  8. (Data in thousand metric tons of silicon content unless otherwise noted) Domestic Production and Use: Estimated value of silicon alloys and metal produced in the United States in 2012

    E-Print Network [OSTI]

    .44 billion. Three companies produced silicon materials in seven plants east of the Mississippi River. Ferrosilicon and metallurgical-grade silicon metal were each produced in four plants. One company produced both and aluminum alloys and the chemical industry. The semiconductor and solar industries, which manufacture chips

  9. (Data in thousand metric tons of silicon content unless otherwise noted) Domestic Production and Use: Estimated value of silicon alloys and metal produced in the United States in 2011

    E-Print Network [OSTI]

    ,400 million. Two companies produced silicon materials in seven plants east of the Mississippi River. Ferrosilicon and metallurgical-grade silicon metal were each produced in four plants. One company produced both and aluminum alloys and the chemical industry. The semiconductor and solar industries, which manufacture chips

  10. Use of High Magnetic Field to Control Microstructural Evolution in Metallic and Magnetic Materials

    SciTech Connect (OSTI)

    Ludtka, G.M.; Mackiewicz- Ludtka, G.; Wilgen, J.B.; Kisner, R.A.

    2010-06-27T23:59:59.000Z

    The Amendment 1, referred to as Phase 2, to the original CRADA NFE-06-00414 added tasks 3 through 7 to the original statement of work that had two main tasks that were successfully accomplished in Phase 1 of this project. In this Phase 2 CRADA extension, extensive research and development activities were conducted using high magnetic field processing effects for the purpose of manipulating microstructure in the SAE 5160 steel to refine grain size isothermally and to develop nanocrystalline spacing pearlite during continuous cooling, and to enhance the formability/forgability of the non-ferrous precipitation hardening magnesium alloy AZ90 by applying a high magnetic field during deformation processing to investigate potential magnetoplasticity in this material. Significant experimental issues (especially non-isothermal conditions evolving upon insertion of an isothermal sample in the high magnetic field) were encountered in the isothermal phase transformation reversal experiments (Task 4) that later were determined to be due to various condensed matter physics phenomenon such as the magnetocaloric (MCE) effect that occurs in the vicinity of a materials Curie temperature. Similarly the experimental deformation rig had components for monitoring deformation/strain (Task 3) that were susceptible to the high magnetic field of the ORNL Thermomagnetic Processing facility 9-T superconducting magnet that caused electronic components to fail or record erroneous (very noisy) signals. Limited experiments on developing nanocrystalline spacing pearlite were not sufficient to elucidate the impact of high magnetic field processing on the final pearlite spacing since significant statistical evaluation of many pearlite colonies would need to be done to be conclusive. Since extensive effort was devoted to resolving issues for Tasks 3 and 7, only results for these focused activities are included in this final CRADA report along with those for Task 7 (described in the Objectives Section of this report).

  11. Semiconductor Engineers in a Global Economy

    E-Print Network [OSTI]

    Brown, Clair; Linden, Greg

    2007-01-01T23:59:59.000Z

    Technology: The Case of Semiconductors. Brookings Institute:Society, Space, and Semiconductors in The Restructuring Ofin the Global Semiconductor Industry. ” California

  12. Synthesis and Characterization of Mesoporous Semiconductors

    E-Print Network [OSTI]

    Kang, Chris Byung-hwa

    2012-01-01T23:59:59.000Z

    Brock, S. L. “Porous semiconductor chalcogenide aerogels. ”Nanostructured Semiconductor. ” J. Am. Chem. Soc. , 127,in mesostructured semiconductors based on the [SnSe 4 ]4-

  13. Semiconductor Nanowires and Nanotubes for Energy Conversion

    E-Print Network [OSTI]

    Fardy, Melissa Anne

    2010-01-01T23:59:59.000Z

    Thermoelectricity in semiconductor nanostructures. Science,splitting using semiconductor electrodes. InternationalChalcogenides, Monographs in Semiconductor Physics, ed. L.S.

  14. Extracting hot carriers from photoexcited semiconductor nanocrystals

    SciTech Connect (OSTI)

    Zhu, Xiaoyang

    2014-12-10T23:59:59.000Z

    This research program addresses a fundamental question related to the use of nanomaterials in solar energy -- namely, whether semiconductor nanocrystals (NCs) can help surpass the efficiency limits, the so-called “Shockley-Queisser” limit, in conventional solar cells. In these cells, absorption of photons with energies above the semiconductor bandgap generates “hot” charge carriers that quickly “cool” to the band edges before they can be utilized to do work; this sets the solar cell efficiency at a limit of ~31%. If instead, all of the energy of the hot carriers could be captured, solar-to-electric power conversion efficiencies could be increased, theoretically, to as high as 66%. A potential route to capture this energy is to utilize semiconductor nanocrystals. In these materials, the quasi-continuous conduction and valence bands of the bulk semiconductor become discretized due to confinement of the charge carriers. Consequently, the energy spacing between the electronic levels can be much larger than the highest phonon frequency of the lattice, creating a “phonon bottleneck” wherein hot-carrier relaxation is possible via slower multiphonon emission. For example, hot-electron lifetimes as long as ~1 ns have been observed in NCs grown by molecular beam epitaxy. In colloidal NCs, long lifetimes have been demonstrated through careful design of the nanocrystal interfaces. Due to their ability to slow electronic relaxation, semiconductor NCs can in principle enable extraction of hot carriers before they cool to the band edges, leading to more efficient solar cells.

  15. Solution Phase Routes to Functional Nanostructured Materials for Energy Applications

    E-Print Network [OSTI]

    Rauda, Iris Ester

    2012-01-01T23:59:59.000Z

    bridge between the structural complexity of templated porous materials, and the electronic and optical complexity of semiconductor

  16. Metalized T graphene: A reversible hydrogen storage material at room temperature

    SciTech Connect (OSTI)

    Ye, Xiao-Juan; Zhong, Wei, E-mail: csliu@njupt.edu.cn, E-mail: wzhong@nju.edu.cn; Du, You-Wei [Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093 (China); Liu, Chun-Sheng, E-mail: csliu@njupt.edu.cn, E-mail: wzhong@nju.edu.cn [Key Laboratory of Radio Frequency and Micro-Nano Electronics of Jiangsu Province, Nanjing University of Posts and Telecommunications, Nanjing 210023 (China); Zeng, Zhi [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China)

    2014-09-21T23:59:59.000Z

    Lithium (Li)-decorated graphene is a promising hydrogen storage medium due to its high capacity. However, homogeneous mono-layer coating graphene with lithium atoms is metastable and the lithium atoms would cluster on the surface, resulting in the poor reversibility. Using van der Waals-corrected density functional theory, we demonstrated that lithium atoms can be homogeneously dispersed on T graphene due to a nonuniform charge distribution in T graphene and strong hybridizations between the C-2p and Li-2p orbitals. Thus, Li atoms are not likely to form clusters, indicating a good reversible hydrogen storage. Both the polarization mechanism and the orbital hybridizations contribute to the adsorption of hydrogen molecules (storage capacity of 7.7 wt. %) with an optimal adsorption energy of 0.19 eV/H?. The adsorption/desorption of H? at ambient temperature and pressure is also discussed. Our results can serve as a guide in the design of new hydrogen storage materials based on non-hexagonal graphenes.

  17. Semiconductor nanocrystal probes for biological applications and process for making and using such probes

    DOE Patents [OSTI]

    Weiss, Shimon; Bruchez, Marcel; Alivisatos, Paul

    2012-10-16T23:59:59.000Z

    A semiconductor nanocrystal compound and probe are described. The compound is capable of linking to one or more affinity molecules. The compound comprises (1) one or more semiconductor nanocrystals capable of, in response to exposure to a first energy, providing a second energy, and (2) one or more linking agents, having a first portion linked to the one or more semiconductor nanocrystals and a second portion capable of linking to one or more affinity molecules. One or more semiconductor nanocrystal compounds are linked to one or more affinity molecules to form a semiconductor nanocrystal probe capable of bonding with one or more detectable substances in a material being analyzed, and capable of, in response to exposure to a first energy, providing a second energy. Also described are processes for respectively: making the semiconductor nanocrystal compound; making the semiconductor nanocrystal probe; and treating materials with the probe.

  18. Semiconductor nanocrystal probes for biological applications and process for making and using such probes

    DOE Patents [OSTI]

    Weiss, Shimon (Pinole, CA); Bruchez, Marcel (Newark, CA); Alivisatos, Paul (Oakland, CA)

    2011-12-06T23:59:59.000Z

    A semiconductor nanocrystal compound and probe are described. The compound is capable of linking to one or more affinity molecules. The compound comprises (1) one or more semiconductor nanocrystals capable of, in response to exposure to a first energy, providing a second energy, and (2) one or more linking agents, having a first portion linked to the one or more semiconductor nanocrystals and a second portion capable of linking to one or more affinity molecules. One or more semiconductor nanocrystal compounds are linked to one or more affinity molecules to form a semiconductor nanocrystal probe capable of bonding with one or more detectable substances in a material being analyzed, and capable of, in response to exposure to a first energy, providing a second energy. Also described are processes for respectively: making the semiconductor nanocrystal compound; making the semiconductor nanocrystal probe; and treating materials with the probe.

  19. Semiconductor nanocrystal probes for biological applications and process for making and using such probes

    DOE Patents [OSTI]

    Weiss, Shimon (Pinole, CA); Bruchez, Marcel (Newark, CA); Alivisatos, Paul (Oakland, CA)

    2011-12-20T23:59:59.000Z

    A semiconductor nanocrystal compound and probe are described. The compound is capable of linking to one or more affinity molecules. The compound comprises (1) one or more semiconductor nanocrystals capable of, in response to exposure to a first energy, providing a second energy, and (2) one or more linking agents, having a first portion linked to the one or more semiconductor nanocrystals and a second portion capable of linking to one or more affinity molecules. One or more semiconductor nanocrystal compounds are linked to one or more affinity molecules to form a semiconductor nanocrystal probe capable of bonding with one or more detectable substances in a material being analyzed, and capable of, in response to exposure to a first energy, providing a second energy. Also described are processes for respectively: making the semiconductor nanocrystal compound; making the semiconductor nanocrystal probe; and treating materials with the probe.

  20. Semiconductor nanocrystal probes for biological applications and process for making and using such probes

    DOE Patents [OSTI]

    Weiss, Shimon; Bruchez, Marcel; Alivisatos, Paul

    2014-01-28T23:59:59.000Z

    A semiconductor nanocrystal compound and probe are described. The compound is capable of linking to one or more affinity molecules. The compound comprises (1) one or more semiconductor nanocrystals capable of, in response to exposure to a first energy, providing a second energy, and (2) one or more linking agents, having a first portion linked to the one or more semiconductor nanocrystals and a second portion capable of linking to one or more affinity molecules. One or more semiconductor nanocrystal compounds are linked to one or more affinity molecules to form a semiconductor nanocrystal probe capable of bonding with one or more detectable substances in a material being analyzed, and capable of, in response to exposure to a first energy, providing a second energy. Also described are processes for respectively: making the semiconductor nanocrystal compound; making the semiconductor nanocrystal probe; and treating materials with the probe.

  1. Electronic-carrier-controlled photochemical etching process in semiconductor device fabrication

    DOE Patents [OSTI]

    Ashby, C.I.H.; Myers, D.R.; Vook, F.L.

    1988-06-16T23:59:59.000Z

    An electronic-carrier-controlled photochemical etching process for carrying out patterning and selective removing of material in semiconductor device fabrication includes the steps of selective ion implanting, photochemical dry etching, and thermal annealing, in that order. In the selective ion implanting step, regions of the semiconductor material in a desired pattern are damaged and the remainder of the regions of the material not implanted are left undamaged. The rate of recombination of electrons and holes is increased in the damaged regions of the pattern compared to undamaged regions. In the photochemical dry etching step which follows ion implanting step, the material in the undamaged regions of the semiconductor are removed substantially faster than in the damaged regions representing the pattern, leaving the ion-implanted, damaged regions as raised surface structures on the semiconductor material. After completion of photochemical dry etching step, the thermal annealing step is used to restore the electrical conductivity of the damaged regions of the semiconductor material.

  2. MATERIALS WORLD January 201216 Dr Steve Barrett from the University of Liverpool, UK, has been studying rare earth metals for

    E-Print Network [OSTI]

    Barrett, Steve D.

    studying rare earth metals for 20 years. Here he explains how preparation of the surface layer is crucial to the functionality of these scarce elements. S tudies into the properties of rare earth metals have been active since of the geometric and electronic structure of single crystal rare earth metal surfaces were published. Studies

  3. Materials Science and Engineering Program Objectives

    E-Print Network [OSTI]

    Lin, Zhiqun

    Materials Science and Engineering Program Objectives Within the scope of the MSE mission, the objectives of the Materials Engineering Program are to produce graduates who: A. practice materials engineering in a broad range of industries including materials production, semiconductors, medical

  4. Hard x-ray emission spectroscopy: a powerful tool for the characterization of magnetic semiconductors

    E-Print Network [OSTI]

    Rovezzi, Mauro

    2014-01-01T23:59:59.000Z

    This review aims to introduce the x-ray emission spectroscopy (XES) and resonant inelastic x-ray scattering (RIXS) techniques to the materials scientist working with magnetic semiconductors (e.g. semiconductors doped with 3d transition metals) for applications in the field of spin-electronics. We focus our attention on the hard part of the x-ray spectrum (above 3 keV) in order to demonstrate a powerful element- and orbital-selective characterization tool in the study of bulk electronic structure. XES and RIXS are photon-in/photon-out second order optical processes described by the Kramers-Heisenberg formula. Nowadays, the availability of third generation synchrotron radiation sources permits to apply such techniques also to dilute materials, opening the way for a detailed atomic characterization of impurity-driven materials. We present the K{\\ss} XES as a tool to study the occupied valence states (directly, via valence-to-core transitions) and to probe the local spin angular momentum (indirectly, via intra-at...

  5. Internal Image Potential in Semiconductors - Effect on Scanning-Tunneling-Microscopy

    E-Print Network [OSTI]

    HUANG, ZH; WEIMER, M.; Allen, Roland E.

    1993-01-01T23:59:59.000Z

    The tunneling of electrons from a semiconductor surface to a metal tip, across a vacuum gap, is influenced by two image interactions: an attractive image potential in the vacuum region, which lowers the apparent tunneling barrier, and a repulsive...

  6. Novel room temperature ferromagnetic semiconductors

    SciTech Connect (OSTI)

    Gupta, Amita

    2004-11-01T23:59:59.000Z

    Today's information world, bits of data are processed by semiconductor chips, and stored in the magnetic disk drives. But tomorrow's information technology may see magnetism (spin) and semiconductivity (charge) combined in one 'spintronic' device that exploits both charge and 'spin' to carry data (the best of two worlds). Spintronic devices such as spin valve transistors, spin light emitting diodes, non-volatile memory, logic devices, optical isolators and ultra-fast optical switches are some of the areas of interest for introducing the ferromagnetic properties at room temperature in a semiconductor to make it multifunctional. The potential advantages of such spintronic devices will be higher speed, greater efficiency, and better stability at a reduced power consumption. This Thesis contains two main topics: In-depth understanding of magnetism in Mn doped ZnO, and our search and identification of at least six new above room temperature ferromagnetic semiconductors. Both complex doped ZnO based new materials, as well as a number of nonoxides like phosphides, and sulfides suitably doped with Mn or Cu are shown to give rise to ferromagnetism above room temperature. Some of the highlights of this work are discovery of room temperature ferromagnetism in: (1) ZnO:Mn (paper in Nature Materials, Oct issue, 2003); (2) ZnO doped with Cu (containing no magnetic elements in it); (3) GaP doped with Cu (again containing no magnetic elements in it); (4) Enhancement of Magnetization by Cu co-doping in ZnO:Mn; (5) CdS doped with Mn, and a few others not reported in this thesis. We discuss in detail the first observation of ferromagnetism above room temperature in the form of powder, bulk pellets, in 2-3 mu-m thick transparent pulsed laser deposited films of the Mn (<4 at. percent) doped ZnO. High-resolution transmission electron microscopy (HRTEM) and electron energy loss spectroscopy (EELS) spectra recorded from 2 to 200nm areas showed homogeneous distribution of Mn substituting for Zn a 2+ state in the ZnO lattice. Ferromagnetic Resonance (FMR) technique is used to confirm the existence of ferromagnetic ordering at temperatures as high as 425K. The ab initio calculations were found to be consistent with the observation of ferromagnetism arising from fully polarized Mn 2+ state. The key to observed room temperature ferromagnetism in this system is the low temperature processing, which prevents formation of clusters, secondary phases and the host ZnO from becoming n-type. The electronic structure of the same Mn doped ZnO thin films studied using XAS, XES and RIXS, revealed a strong hybridization between Mn 3d and O 2p states, which is an important characteristic of a Dilute magnetic Semiconductor (DMS). It is shown that the various processing conditions like sintering temperature, dopant concentration and the properties of precursors used for making of DMS have a great influence on the final properties. Use of various experimental techniques to verify the physical properties, and to understand the mechanism involved to give rise to ferromagnetism is presented. Methods to improve the magnetic moment in Mn doped ZnO are also described. New promising DMS materials (such as Cu doped ZnO are explored). The demonstrated new capability to fabricate powder, pellets, and thin films of room temperature ferromagnetic semiconductors thus makes possible the realization of a wide range of complex elements for a variety of new multifunctional phenomena related to Spintronic devices as well as magneto-optic components.

  7. Three-Dimensional Topological Insulators in I-III-VI2 and II-IV-V2 Chalcopyrite Semiconductors

    SciTech Connect (OSTI)

    Feng, wanxiang [Chinese Academy of Sciences; Ding, Jun [Beijing National Laboratory for Condensed Matter Physics/Chinese Academy of Scie; Xiao, Di [ORNL; Yao, yugui [Chinese Academy of Sciences

    2011-01-01T23:59:59.000Z

    The recent discovery of topological insulators with exotic metallic surface states has garnered great interest in the fields of condensed matter physics and materials science.1 A number of spectacular quantum phenomena have been predicted when the surface states are under the influence of magnetism and superconductivity,2 5 which could open up new opportunities for technological applications in spintronics and quantum computing. To achieve this goal, material realization of topological insulators with desired physical properties is of crucial importance. Based on first-principles calculations, here we show that a large number of ternary chalcopyrite compounds of composition I-III-VI2 and II-IV-V2 can realize the topological insulating phase in their native states. The crystal structure of chalcopyrites is derived from the frequently used zinc-blende structure, and many of them possess a close lattice match to important mainstream semiconductors, which is essential for a smooth integration into current semiconductor technology. The diverse optical, electrical and structural properties of chalcopyrite semiconductors,6 and particularly their ability to host room-temperature ferromagnetism,7 9 make them appealing candidates for novel spintronic devices.

  8. Three-Dimensional Topological Insulators in I-III-VI$_2$ and II-IV-V$_2$ Chalcopyrite Semiconductors

    E-Print Network [OSTI]

    Wanxiang Feng; Jun Ding; Di Xiao; Yugui Yao

    2010-07-31T23:59:59.000Z

    The recent discovery of topological insulators with exotic metallic surface states has garnered great interest in the fields of condensed matter physics and materials science. A number of spectacular quantum phenomena have been predicted when the surface states are under the influence of magnetism and superconductivity, which could open up new opportunities for technological applications in spintronics and quantum computing. To achieve this goal, material realization of topological insulators with desired physical properties is of crucial importance. Based on first-principles calculations, here we show that a large number of ternary chalcopyrite compounds of composition I-III-VI$_2$ and II-IV-V$_2$ can realize the topological insulating phase in their native states. The crystal structure of chalcopyrites is derived from the frequently used zinc-blende structure, and many of them possess a close lattice match to important mainstream semiconductors, which is essential for a smooth integration into current semiconductor technology. The diverse optical, electrical and structural properties of chalcopyrite semiconductors, and particularly their ability to host room-temperature ferromagnetism, make them appealing candidates for novel spintronic devices.

  9. Printable semiconductor structures and related methods of making and assembling

    DOE Patents [OSTI]

    Nuzzo, Ralph G. (Champaign, IL); Rogers, John A. (Champaign, IL); Menard, Etienne (Urbana, IL); Lee, Keon Jae (Tokyo, JP); Khang, Dahl-Young (Urbana, IL); Sun, Yugang (Westmont, IL); Meitl, Matthew (Champaign, IL); Zhu, Zhengtao (Rapid City, SD); Ko, Heung Cho (Urbana, IL); Mack, Shawn (Goleta, CA)

    2010-09-21T23:59:59.000Z

    The present invention provides a high yield pathway for the fabrication, transfer and assembly of high quality printable semiconductor elements having selected physical dimensions, shapes, compositions and spatial orientations. The compositions and methods of the present invention provide high precision registered transfer and integration of arrays of microsized and/or nanosized semiconductor structures onto substrates, including large area substrates and/or flexible substrates. In addition, the present invention provides methods of making printable semiconductor elements from low cost bulk materials, such as bulk silicon wafers, and smart-materials processing strategies that enable a versatile and commercially attractive printing-based fabrication platform for making a broad range of functional semiconductor devices.

  10. Printable semiconductor structures and related methods of making and assembling

    DOE Patents [OSTI]

    Nuzzo, Ralph G.; Rogers, John A.; Menard, Etienne; Lee, Keon Jae; Khang; , Dahl-Young; Sun, Yugang; Meitl, Matthew; Zhu, Zhengtao; Ko, Heung Cho; Mack, Shawn

    2013-03-12T23:59:59.000Z

    The present invention provides a high yield pathway for the fabrication, transfer and assembly of high quality printable semiconductor elements having selected physical dimensions, shapes, compositions and spatial orientations. The compositions and methods of the present invention provide high precision registered transfer and integration of arrays of microsized and/or nanosized semiconductor structures onto substrates, including large area substrates and/or flexible substrates. In addition, the present invention provides methods of making printable semiconductor elements from low cost bulk materials, such as bulk silicon wafers, and smart-materials processing strategies that enable a versatile and commercially attractive printing-based fabrication platform for making a broad range of functional semiconductor devices.

  11. Printable semiconductor structures and related methods of making and assembling

    DOE Patents [OSTI]

    Nuzzo, Ralph G. (Champaign, IL); Rogers, John A. (Champaign, IL); Menard, Etienne (Durham, NC); Lee, Keon Jae (Tokyo, JP); Khang, Dahl-Young (Urbana, IL); Sun, Yugang (Westmont, IL); Meitl, Matthew (Raleigh, NC); Zhu, Zhengtao (Rapid City, SD); Ko, Heung Cho (Urbana, IL); Mack, Shawn (Goleta, CA)

    2011-10-18T23:59:59.000Z

    The present invention provides a high yield pathway for the fabrication, transfer and assembly of high quality printable semiconductor elements having selected physical dimensions, shapes, compositions and spatial orientations. The compositions and methods of the present invention provide high precision registered transfer and integration of arrays of microsized and/or nanosized semiconductor structures onto substrates, including large area substrates and/or flexible substrates. In addition, the present invention provides methods of making printable semiconductor elements from low cost bulk materials, such as bulk silicon wafers, and smart-materials processing strategies that enable a versatile and commercially attractive printing-based fabrication platform for making a broad range of functional semiconductor devices.

  12. Energy resolution in semiconductor gamma radiation detectors using heterojunctions and methods of use and preparation thereof

    DOE Patents [OSTI]

    Nikolic, Rebecca J.; Conway, Adam M.; Nelson, Art J.; Payne, Stephen A.

    2012-09-04T23:59:59.000Z

    In one embodiment, a system comprises a semiconductor gamma detector material and a hole blocking layer adjacent the gamma detector material, the hole blocking layer resisting passage of holes therethrough. In another embodiment, a system comprises a semiconductor gamma detector material, and an electron blocking layer adjacent the gamma detector material, the electron blocking layer resisting passage of electrons therethrough, wherein the electron blocking layer comprises undoped HgCdTe. In another embodiment, a method comprises forming a hole blocking layer adjacent a semiconductor gamma detector material, the hole blocking layer resisting passage of holes therethrough. Additional systems and methods are also presented.

  13. Quantum Semiconductor Modeling Ansgar Jungel

    E-Print Network [OSTI]

    Jüngel, Ansgar

    Quantum Semiconductor Modeling Ansgar J¨ungel Vienna University of Technology, Austria www.jungel.at.vu Ansgar J¨ungel (TU Wien) Quantum Semiconductor Modeling www.jungel.at.vu 1 / 154 #12;Contents 1 Introduction 2 Semiconductor modeling 3 Microscopic quantum models Density matrices Schr¨odinger models Wigner

  14. Alleviation of fermi-level pinning effect at metal/germanium interface by the insertion of graphene layers

    SciTech Connect (OSTI)

    Baek, Seung-heon Chris; Seo, Yu-Jin; Oh, Joong Gun; Albert Park, Min Gyu; Bong, Jae Hoon; Yoon, Seong Jun; Lee, Seok-Hee, E-mail: seokheelee@ee.kaist.ac.kr [Department of Electrical Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Seo, Minsu; Park, Seung-young [Division of Materials Science, Korea Basic Science Institute (KBSI), 169-148 Daehak-ro, Yuseong-gu, Daejeon 305-333 (Korea, Republic of); Park, Byong-Guk [Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)

    2014-08-18T23:59:59.000Z

    In this paper, we report the alleviation of the Fermi-level pinning on metal/n-germanium (Ge) contact by the insertion of multiple layers of single-layer graphene (SLG) at the metal/n-Ge interface. A decrease in the Schottky barrier height with an increase in the number of inserted SLG layers was observed, which supports the contention that Fermi-level pinning at metal/n-Ge contact originates from the metal-induced gap states at the metal/n-Ge interface. The modulation of Schottky barrier height by varying the number of inserted SLG layers (m) can bring about the use of Ge as the next-generation complementary metal-oxide-semiconductor material. Furthermore, the inserted SLG layers can be used as the tunnel barrier for spin injection into Ge substrate for spin-based transistors.

  15. Dielectric function of diluted magnetic semiconductors in the infrared regime

    E-Print Network [OSTI]

    Aguado, R.; Lopez-Sancho, MP; Sinova, Jairo; Brey, L.

    2004-01-01T23:59:59.000Z

    We present a study of the dielectric function of metallic (III,Mn)V diluted magnetic semiconductors in the infrared regime. Our theoretical approach is based on the kinetic exchange model for carrier induced (III,Mn)V ferromagnetism. The dielectric...

  16. Organo luminescent semiconductor nanocrystal probes for biological applications and process for making and using such probes

    DOE Patents [OSTI]

    Weiss, Shimon (Pinole, CA); Bruchez, Jr., Marcel (Albany, CA); Alivisatos, Paul (Oakland, CA)

    2002-01-01T23:59:59.000Z

    A semiconductor nanocrystal compound is described capable of linking to an affinity molecule. The compound comprises (1) a semiconductor nanocrystal capable of emitting electromagnetic radiation and/or absorbing energy, and/or scattering or diffracting electromagnetic radiation--when excited by an electromagnetic radiation source or a particle beam; and (2) at least one linking agent, having a first portion linked to the semiconductor nanocrystal and a second portion capable of linking to an affity molecule. The compound is linked to an affinity molecule to form a semiconductor nanocrystal probe capable of bonding with a detectable substance. Subsequent exposure to excitation energy will excite the semiconductor nanocrystal in he probe, causing the emission of electromagnetic radiation. Further described are processes for respectively: making the semiconductor nanocrystal compound; making the semiconductor nanocrystal probe; and using the probe to determine the presence of a detectable substance in a material.

  17. Organo luminescent semiconductor nanocrystal probes for biological applications and process for making and using such probes

    DOE Patents [OSTI]

    Weiss, Shimon (Pinole, CA); Bruchez, Jr., Marcel (Albany, CA); Alivisatos, Paul (Oakland, CA)

    2004-03-02T23:59:59.000Z

    A semiconductor nanocrystal compound is described capable of linking to an affinity molecule. The compound comprises (1) a semiconductor nanocrystal capable of emitting electromagnetic radiation and/or absorbing energy, and/or scattering or diffracting electromagnetic radiation--when excited by an electromagnetic radiation source or a particle beam; and (2) at least one linking agent, having a first portion linked to the semiconductor nanocrystal and a second portion capable of linking to an affinity molecule. The compound is linked to an affinity molecule to form a semiconductor nanocrystal probe capable of bonding with a detectable substance. Subsequent exposure to excitation energy will excite the semiconductor nanocrystal in the probe, causing the emission of electromagnetic radiation. Further described are processes for respectively: making the semiconductor nanocrystal compound; making the semiconductor nanocrystal probe; and using the probe to determine the presence of a detectable substance in a material.

  18. Organo luminescent semiconductor nanocrystal probes for biological applications and process for making and using such probes

    DOE Patents [OSTI]

    Weiss, Shimon; Bruchez, Jr., Marcel; Alivisatos, Paul

    2005-08-09T23:59:59.000Z

    A semiconductor nanocrystal compound is described capable of linking to an affinity molecule. The compound comprises (1) a semiconductor nanocrystal capable of emitting electromagnetic radiation and/or absorbing energy, and/or scattering or diffracting electromagnetic radiation--when excited by an electromagnetic radiation source or a particle beam; and (2) at least one linking agent, having a first portion linked to the semiconductor nanocrystal and a second portion capable of linking to an affinity molecule. The compound is linked to an affinity molecule to form a semiconductor nanocrystal probe capable of bonding with a detectable substance. Subsequent exposure to excitation energy will excite the semiconductor nanocrystal in the probe causing the emission of electromagnetic radiation. Further described are processes for respectively: making the luminescent semiconductor nanocrystal compound; making the semiconductor nanocrystal probe; and using the probe to determine the presence of a detectable substance in a material.

  19. Organo luminescent semiconductor nanocrystal probes for biological applications and process for making and using such probes

    DOE Patents [OSTI]

    Weiss, Shimon; Bruchez, Jr., Marcel; Alivisatos, Paul

    2006-09-05T23:59:59.000Z

    A semiconductor nanocrystal compound is described capable of linking to an affinity molecule. The compound comprises (1) a semiconductor nanocrystal capable of emitting electromagnetic radiation and/or absorbing energy, and/or scattering or diffracting electromagnetic radiation--when excited by an electromagnetic radiation source or a particle beam; and (2) at least one linking agent, having a first portion linked to the semiconductor nanocrystal and a second portion capable of linking to an affinity molecule. The compound is linked to an affinity molecule to form a semiconductor nanocrystal probe capable of bonding with a detectable substance. subsequent exposure to excitation energy will excite the semiconductor nanocrystal in the probe causing the emission of electromagnetic radiation. Further described are processes for respectively: making the luminescent semiconductor nanocrystal compound; making the semiconductor nanocrystal probe; and using the probe to determine the presence of a detectable substance in a material.

  20. GaTe semiconductor for radiation detection

    DOE Patents [OSTI]

    Payne, Stephen A. (Castro Valley, CA); Burger, Arnold (Nashville, TN); Mandal, Krishna C. (Ashland, MA)

    2009-06-23T23:59:59.000Z

    GaTe semiconductor is used as a room-temperature radiation detector. GaTe has useful properties for radiation detectors: ideal bandgap, favorable mobilities, low melting point (no evaporation), non-hygroscopic nature, and availability of high-purity starting materials. The detector can be used, e.g., for detection of illicit nuclear weapons and radiological dispersed devices at ports of entry, in cities, and off shore and for determination of medical isotopes present in a patient.

  1. Scanning probe microscopy studies of semiconductor surfaces

    SciTech Connect (OSTI)

    Weinberg, W.H. [Univ. of California, Santa Barbara, CA (United States)

    1996-10-01T23:59:59.000Z

    Recent work involving atomic force microscopy and scanning tunneling microscopy is discussed which involves strain-induced, self-assembling nanostructures in compound semiconductor materials. Specific examples include one-dimensional quantum wires of InAs grown by MBE on GaAs(001) and zero-dimensional quantum dots of InP grown by MOCVD on InGaP which is lattice matched to GaAs(001).

  2. Kansas Advanced Semiconductor Project

    SciTech Connect (OSTI)

    Baringer, P.; Bean, A.; Bolton, T.; Horton-Smith, G.; Maravin, Y.; Ratra, B.; Stanton, N.; von Toerne, E.; Wilson, G.

    2007-09-21T23:59:59.000Z

    KASP (Kansas Advanced Semiconductor Project) completed the new Layer 0 upgrade for D0, assumed key electronics projects for the US CMS project, finished important new physics measurements with the D0 experiment at Fermilab, made substantial contributions to detector studies for the proposed e+e- international linear collider (ILC), and advanced key initiatives in non-accelerator-based neutrino physics.

  3. FWP executive summaries, Basic Energy Sciences Materials Sciences Programs (SNL/NM)

    SciTech Connect (OSTI)

    Samara, G.A.

    1997-05-01T23:59:59.000Z

    The BES Materials Sciences Program has the central theme of Scientifically Tailored Materials. The major objective of this program is to combine Sandia`s expertise and capabilities in the areas of solid state sciences, advanced atomic-level diagnostics and materials synthesis and processing science to produce new classes of tailored materials as well as to enhance the properties of existing materials for US energy applications and for critical defense needs. Current core research in this program includes the physics and chemistry of ceramics synthesis and processing, the use of energetic particles for the synthesis and study of materials, tailored surfaces and interfaces for materials applications, chemical vapor deposition sciences, artificially-structured semiconductor materials science, advanced growth techniques for improved semiconductor structures, transport in unconventional solids, atomic-level science of interfacial adhesion, high-temperature superconductors, and the synthesis and processing of nano-size clusters for energy applications. In addition, the program includes the following three smaller efforts initiated in the past two years: (1) Wetting and Flow of Liquid Metals and Amorphous Ceramics at Solid Interfaces, (2) Field-Structured Anisotropic Composites, and (3) Composition-Modulated Semiconductor Structures for Photovoltaic and Optical Technologies. The latter is a joint effort with the National Renewable Energy Laboratory. Separate summaries are given of individual research areas.

  4. Materials

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes |IsLove Your Home andDisposition | NationalMaterials

  5. Synthesis and Characterization of Mesoporous Semiconductors and Their Energy Applications

    E-Print Network [OSTI]

    Kang, Chris Byung-hwa

    2013-01-01T23:59:59.000Z

    Biomaterials, Ceramics, and Semiconductors. ” Science, 277,I. “Nanostructured Semiconductors Templated by Cholesteryl-Nanostructured Semiconductor. ” J. Am. Chem. Soc. , 127,

  6. A Novel Class of High-TC Ferromagnetic Semiconductors

    E-Print Network [OSTI]

    Shlyk, L. V.

    2008-01-01T23:59:59.000Z

    Diluted magnetic semiconductor or clustering effect? ”,ferromagnetism in semiconductors”, J. Appl. Phys. , inMaking nonmagnetic semiconductors ferromagnetic”, Science,

  7. MICROSTRUCTURE-PROPERTY RELATIONSHIPS OF A ZINC OXIDE VARISTOR MATERIAL

    E-Print Network [OSTI]

    Williama, Pamela Louise

    2011-01-01T23:59:59.000Z

    RELATIONSHIPS OF A ZINC OXIDE VARISTOR MATERIAL Pamelaresistors, and zinc oxide varistors are semiconductorRELATIONSHIPS OF A ZINC OXIDE VARISTOR MATERIAL CONTENTS

  8. Solution Phase Routes to Functional Nanostructured Materials for Energy Applications

    E-Print Network [OSTI]

    Rauda, Iris Ester

    2012-01-01T23:59:59.000Z

    synthesis of inorganic semiconductor-based nanostructured materials;inorganic materials. 16,35,62?72 In the synthesis, we begin

  9. Topsil Semiconductor Materials AS | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty Edit withTianlin Baxin Hydropower Station Jump to:TiogaTongdaoToolToppan Printing

  10. Advances in metal matrix composite packaging for use in alternative energy transportation systems

    SciTech Connect (OSTI)

    Martinez, J.L. Jr.; Fusaro, J.M.; Romero, G.L. [Motorola Inc., Phoenix, AZ (United States)] [and others

    1996-12-31T23:59:59.000Z

    The packaging of power semiconductors for use in ac motor control inverters for zero-emission vehicles has typically included a copper baseplate onto which a ceramic isolation structure is mounted. The ceramic isolation Structure is used to mount semiconductor devices and mechanically route the electrical Circuit. All components, including buss bars, are encased in a molded plastic housing. Due to its high thermal conductivity and low cost, copper has been the material of choice for baseplates in the manufacture of power modules. In operation, the power module is required to dissipate large amounts of heat generated by the semiconductor devices. Thermal and mechanical stresses are induced into the package due to the differences in the coefficient of thermal expansion (CTE) between the various materials. These stresses are large enough to produce cracks in the ceramic and solder bonding layers. The cracking of material in either case inhibits the removal of heat from the semiconductor devices and eventually causessemiconductor device failure. Metal Matrix Composites (MMC`s) have been used in the aerospace industry for years in structural designs and in the packaging of electronic components. Motorola`s Hybrid Power Module Operation (HPM) has been investigating MMC`s, particularly Aluminum/Silicon Carbide (AISiC), for use as the baseplate of power modules. The properties of AISiC, particularly its CTE and thermal conductivity, have made it a viable candidate to replace copper in these applications. Findings on thermal performance, reliability, manufacturability, and package integration are presented.

  11. Thermoelectric power factor in semiconductors with buried epitaxial semimetallic nanoparticles

    E-Print Network [OSTI]

    Bowers, John

    Thermoelectric power factor in semiconductors with buried epitaxial semimetallic nanoparticles J. M, mobility, and Seebeck coefficient of these materials and discuss their potential for use in thermoelectric on thermoelectric materials has focused on the ability of heterostructures and quantum con- finement to increase

  12. Methods of forming semiconductor devices and devices formed using such methods

    DOE Patents [OSTI]

    Fox, Robert V; Rodriguez, Rene G; Pak, Joshua

    2013-05-21T23:59:59.000Z

    Single source precursors are subjected to carbon dioxide to form particles of material. The carbon dioxide may be in a supercritical state. Single source precursors also may be subjected to supercritical fluids other than supercritical carbon dioxide to form particles of material. The methods may be used to form nanoparticles. In some embodiments, the methods are used to form chalcopyrite materials. Devices such as, for example, semiconductor devices may be fabricated that include such particles. Methods of forming semiconductor devices include subjecting single source precursors to carbon dioxide to form particles of semiconductor material, and establishing electrical contact between the particles and an electrode.

  13. Scientists Connect Thermoelectric Materials and Topological Insulators...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    that does not occur in normal semiconductors. Thermoelectric materials enable scalable direct conversion of heat to electricity in solid state devices, and have potential for...

  14. Semiconductor radiation detector

    DOE Patents [OSTI]

    Patt, Bradley E. (Sherman Oaks, CA); Iwanczyk, Jan S. (Los Angeles, CA); Tull, Carolyn R. (Orinda, CA); Vilkelis, Gintas (Westlake Village, CA)

    2002-01-01T23:59:59.000Z

    A semiconductor radiation detector is provided to detect x-ray and light photons. The entrance electrode is segmented by using variable doping concentrations. Further, the entrance electrode is physically segmented by inserting n+ regions between p+ regions. The p+ regions and the n+ regions are individually biased. The detector elements can be used in an array, and the p+ regions and the n+ regions can be biased by applying potential at a single point. The back side of the semiconductor radiation detector has an n+ anode for collecting created charges and a number of p+ cathodes. Biased n+ inserts can be placed between the p+ cathodes, and an internal resistor divider can be used to bias the n+ inserts as well as the p+ cathodes. A polysilicon spiral guard can be implemented surrounding the active area of the entrance electrode or surrounding an array of entrance electrodes.

  15. ESTABLISHING SUSTAINABLE US HEV/PHEV MANUFACTURING BASE: STABILIZED LITHIUM METAL POWDER, ENABLING MATERIAL AND REVOLUTIONARY TECHNOLOGY FOR HIGH ENERGY LI-ION BATTERIES

    SciTech Connect (OSTI)

    Yakovleva, Marina

    2012-12-31T23:59:59.000Z

    FMC Lithium Division has successfully completed the project “Establishing Sustainable US PHEV/EV Manufacturing Base: Stabilized Lithium Metal Powder, Enabling Material and Revolutionary Technology for High Energy Li-ion Batteries”. The project included design, acquisition and process development for the production scale units to 1) produce stabilized lithium dispersions in oil medium, 2) to produce dry stabilized lithium metal powders, 3) to evaluate, design and acquire pilot-scale unit for alternative production technology to further decrease the cost, and 4) to demonstrate concepts for integrating SLMP technology into the Li- ion batteries to increase energy density. It is very difficult to satisfy safety, cost and performance requirements for the PHEV and EV applications. As the initial step in SLMP Technology introduction, industry can use commercially available LiMn2O4 or LiFePO4, for example, that are the only proven safer and cheaper lithium providing cathodes available on the market. Unfortunately, these cathodes alone are inferior to the energy density of the conventional LiCoO2 cathode and, even when paired with the advanced anode materials, such as silicon composite material, the resulting cell will still not meet the energy density requirements. We have demonstrated, however, if SLMP Technology is used to compensate for the irreversible capacity in the anode, the efficiency of the cathode utilization will be improved and the cost of the cell, based on the materials, will decrease.

  16. Recommendation 221: Recommendation Regarding Recycling of Metals...

    Office of Environmental Management (EM)

    221: Recommendation Regarding Recycling of Metals and Materials Recommendation 221: Recommendation Regarding Recycling of Metals and Materials In addition to the DOE making a final...

  17. Semiconductor Ion Implanters

    SciTech Connect (OSTI)

    MacKinnon, Barry A. [Isys, 2727 Walsh Ave., Suite 103, Santa Clara, CA 95051 (United States); Ruffell, John P. [Group 3, LLC, Sunnyvale, CA 94086 (United States)

    2011-06-01T23:59:59.000Z

    In 1953 the Raytheon CK722 transistor was priced at $7.60. Based upon this, an Intel Xeon Quad Core processor containing 820,000,000 transistors should list at $6.2 billion. Particle accelerator technology plays an important part in the remarkable story of why that Intel product can be purchased today for a few hundred dollars. Most people of the mid twentieth century would be astonished at the ubiquity of semiconductors in the products we now buy and use every day. Though relatively expensive in the nineteen fifties they now exist in a wide range of items from high-end multicore microprocessors like the Intel product to disposable items containing 'only' hundreds or thousands like RFID chips and talking greeting cards. This historical development has been fueled by continuous advancement of the several individual technologies involved in the production of semiconductor devices including Ion Implantation and the charged particle beamlines at the heart of implant machines. In the course of its 40 year development, the worldwide implanter industry has reached annual sales levels around $2B, installed thousands of dedicated machines and directly employs thousands of workers. It represents in all these measures, as much and possibly more than any other industrial application of particle accelerator technology. This presentation discusses the history of implanter development. It touches on some of the people involved and on some of the developmental changes and challenges imposed as the requirements of the semiconductor industry evolved.

  18. WWW.MOTOROLA.COM/SEMICONDUCTORS Microcontrollers

    E-Print Network [OSTI]

    Song, Joe

    WWW.MOTOROLA.COM/SEMICONDUCTORS M68HC11 Microcontrollers M68HC11RM/D Rev. 6, 4/2002 M68HC11 Reference Manual FreescaleSemiconductor,I Freescale Semiconductor, Inc. For More Information On This Product, Go to: www.freescale.com nc... #12;FreescaleSemiconductor,I Freescale Semiconductor, Inc. For More

  19. Semiconductor Probes of Light Dark Matter

    E-Print Network [OSTI]

    Peter W. Graham; David E. Kaplan; Surjeet Rajendran; Matthew T. Walters

    2012-11-12T23:59:59.000Z

    Dark matter with mass below about a GeV is essentially unobservable in conventional direct detection experiments. However, newly proposed technology will allow the detection of single electron events in semiconductor materials with significantly lowered thresholds. This would allow detection of dark matter as light as an MeV in mass. Compared to other detection technologies, semiconductors allow enhanced sensitivity because of their low ionization energy around an eV. Such detectors would be particularly sensitive to dark matter with electric and magnetic dipole moments, with a reach many orders of magnitude beyond current bounds. Observable dipole moment interactions can be generated by new particles with masses as great as 1000 TeV, providing a window to scales beyond the reach of current colliders.

  20. AC 2010-1276: STUDENT UNDERSTANDING OF THE MECHANICAL PROPERTIES OF METALS IN AN INTRODUCTORY MATERIALS SCIENCE

    E-Print Network [OSTI]

    Heckler, Andrew F.

    difficulties in learning materials science. © American Society for Engineering Education, 2010 #12;Student in a university-level introductory materials science course for engineers. Through interviews of over 80 students MATERIALS SCIENCE ENGINEERING COURSE Rebecca Rosenblatt, Ohio State University Rebecca Rosenblatt

  1. Sandia National Laboratories: compound semiconductor

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    compound semiconductor Sandia and EMCORE: Solar Photovoltaics, Fiber Optics, MODE, and Energy Efficiency On March 29, 2013, in Concentrating Solar Power, Energy, Partnership,...

  2. Nano-composite materials

    DOE Patents [OSTI]

    Lee, Se-Hee; Tracy, C. Edwin; Pitts, J. Roland

    2010-05-25T23:59:59.000Z

    Nano-composite materials are disclosed. An exemplary method of producing a nano-composite material may comprise co-sputtering a transition metal and a refractory metal in a reactive atmosphere. The method may also comprise co-depositing a transition metal and a refractory metal composite structure on a substrate. The method may further comprise thermally annealing the deposited transition metal and refractory metal composite structure in a reactive atmosphere.

  3. Low frequency noise in GaN metal semiconductor and metal oxide semiconductor field effect transistors

    E-Print Network [OSTI]

    Pala, Nezih

    , and Systems Engineering and Center for Integrated Electronics and Electronics Manufacturing, CII 9017, University of South Carolina, Columbia, South Carolina 29208 Received 22 January 2001; accepted American Institute of Physics. DOI: 10.1063/1.1372364 I. INTRODUCTION A recent report on GaN highly doped

  4. Durable metallized polymer mirror

    DOE Patents [OSTI]

    Schissel, Paul O. (Golden, CO); Kennedy, Cheryl E. (Lafayette, CO); Jorgensen, Gary J. (Pine, CO); Shinton, Yvonne D. (Northglenn, CO); Goggin, Rita M. (Englewood, CO)

    1994-01-01T23:59:59.000Z

    A metallized polymer mirror construction having improved durability against delamination and tunneling, comprising: an outer layer of polymeric material; a metal oxide layer underlying the outer layer of polymeric material; a silver reflective layer underneath the metal oxide layer; and a layer of adhesive attaching the silver layer to a substrate.

  5. Durable metallized polymer mirror

    DOE Patents [OSTI]

    Schissel, P.O.; Kennedy, C.E.; Jorgensen, G.J.; Shinton, Y.D.; Goggin, R.M.

    1994-11-01T23:59:59.000Z

    A metallized polymer mirror construction is disclosed having improved durability against delamination and tunneling, comprising: an outer layer of polymeric material; a metal oxide layer underlying the outer layer of polymeric material; a silver reflective layer underneath the metal oxide layer; and a layer of adhesive attaching the silver layer to a substrate. 6 figs.

  6. Noise and synamics in semiconductor lasers

    E-Print Network [OSTI]

    Rana, Farhan, 1971-

    2003-01-01T23:59:59.000Z

    In this thesis, theoretical and experimental work on the noise and dynamics in continuous wave and mode-locked semiconductor lasers is presented. The main focus is on semiconductor cascade lasers and semiconductor mode-locked ...

  7. Semiconductors: From Manipulated to Managed Trade

    E-Print Network [OSTI]

    Tyson, Laura D'Andrea; Yoffie, David B.

    1991-01-01T23:59:59.000Z

    o f the Japanese semiconductor industry is a sucecsslul aridcommodnv product Ol the semiconductor industry. They are afor maJtini: semiconductors: »nc

  8. Electron vortices in semiconductors devicesa... Kamran Mohsenib

    E-Print Network [OSTI]

    Electron vortices in semiconductors devicesa... Kamran Mohsenib Aerospace Engineering Sciencies; published online 3 October 2005 The hydrodynamic model of electron transport in semiconductors is analyzed vorticity effects. Furthermore, conditions for observation of electron vortices in semiconductor devices

  9. On the State of the Art of Metal Interconnects for SOFC Application

    SciTech Connect (OSTI)

    Jablonski@netl.doe.gov

    2011-02-27T23:59:59.000Z

    One of the recent developments for Solid Oxide Fuel Cells (SOFC) is oxide component materials capable of operating at lower temperatures such as 700-800C. This lower temperature range has provided for the consideration of metallic interconnects which have several advantages over ceramic interconnects: low cost, ease in manufacturing, and high conductivity. Most metals and alloys will oxidize under both the anode and cathode conditions within an SOFC, thus a chief requirement is that the base metal oxide scale must be electrically conductive since this constitutes the majority of the electrical resistance in a metallic interconnect. Common high temperature alloys form scales that contain chrome, silicon and aluminum oxides among others. Under SOFC operating conditions chrome oxide is a semi-conductor while silicon and aluminum oxides are insulators. In this talk we will review the evolution in candidate alloys and surface modifications which constitute an engineered solution for SOFC interconnect applications.

  10. Reactive codoping of GaAlInP compound semiconductors

    DOE Patents [OSTI]

    Hanna, Mark Cooper (Boulder, CO); Reedy, Robert (Golden, CO)

    2008-02-12T23:59:59.000Z

    A GaAlInP compound semiconductor and a method of producing a GaAlInP compound semiconductor are provided. The apparatus and method comprises a GaAs crystal substrate in a metal organic vapor deposition reactor. Al, Ga, In vapors are prepared by thermally decomposing organometallic compounds. P vapors are prepared by thermally decomposing phospine gas, group II vapors are prepared by thermally decomposing an organometallic group IIA or IIB compound. Group VIB vapors are prepared by thermally decomposing a gaseous compound of group VIB. The Al, Ga, In, P, group II, and group VIB vapors grow a GaAlInP crystal doped with group IIA or IIB and group VIB elements on the substrate wherein the group IIA or IIB and a group VIB vapors produced a codoped GaAlInP compound semiconductor with a group IIA or IIB element serving as a p-type dopant having low group II atomic diffusion.

  11. Method for measuring the drift mobility in doped semiconductors

    DOE Patents [OSTI]

    Crandall, R.S.

    1982-03-09T23:59:59.000Z

    A method for measuring the drift mobility of majority carriers in semiconductors consists of measuring the current transient in a Schottky-barrier device following the termination of a forward bias pulse. An example is given using an amorphous silicon hydrogenated material doped with 0.2% phosphorus. The method is particularly useful with material in which the dielectric relaxation time is shorter than the carrier transit time. It is particularly useful in material useful in solar cells. 10 figs.

  12. Method for measuring the drift mobility in doped semiconductors

    DOE Patents [OSTI]

    Crandall, Richard S. (Princeton, NJ)

    1982-01-01T23:59:59.000Z

    A method for measuring the drift mobility of majority carriers in semiconductors consists of measuring the current transient in a Schottky-barrier device following the termination of a forward bias pulse. An example is given using an amorphous silicon hydrogenated material doped with 0.2% phosphorous. The method is particularly useful with material in which the dielectric relaxation time is shorter than the carrier transit time. It is particularly useful in material useful in solar cells.

  13. LCD, low-temperature soldering and compound semiconductor : the sources, market, applications and future prospects of indium in Malaysia

    E-Print Network [OSTI]

    Yong, Foo Nun

    2006-01-01T23:59:59.000Z

    Indium is a minor but very valuable metal. Decreasing supplies of indium from refining and increasing demands from LCD, low-temperature soldering and compound semiconductors have stimulated the indium price increase ...

  14. Climate VISION: Private Sector Initiatives: Semiconductors

    Office of Scientific and Technical Information (OSTI)

    Agreements The U.S. semiconductor industry, represented by the members of the Environmental Protection Agency's PFC ReductionClimate Partnership for the Semiconductor...

  15. Climate VISION: Private Sector Initiatives: Semiconductors: Resources...

    Office of Scientific and Technical Information (OSTI)

    over 100 companies that account for more than 83% of U.S.-based semiconductor production. The SIA provides a forum for domestic semiconductor companies to work collectively...

  16. Characterization of Amorphous Zinc Tin Oxide Semiconductors....

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Amorphous Zinc Tin Oxide Semiconductors. Characterization of Amorphous Zinc Tin Oxide Semiconductors. Abstract: Amorphous zinc tin oxide (ZTO) was investigated to determine the...

  17. Opportunities for Wide Bandgap Semiconductor Power Electronics...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Opportunities for Wide Bandgap Semiconductor Power Electronics for Hydrogen and Fuel Cell Applications Opportunities for Wide Bandgap Semiconductor Power Electronics for Hydrogen...

  18. Functional Materials Letters (FML) Metal-to-dielectric transition induced by annealing of oriented titanium thin films

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    titanium thin films --Manuscript Draft-- Manuscript Number: Full Title: Metal-to-dielectric transition induced by annealing of oriented titanium thin films Article Type: Research Paper Section/Category: Prof. Order of Authors Secondary Information: Abstract: Titanium thin films were deposited by dc magnetron

  19. Materials Technical Team Roadmap

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    of these as mixed- material systems. Additionally, materials such as titanium, polycarbonate, acrylics, and metal matrix composites, and approaches to their use must be...

  20. Photoelectrochemistry in particulate systems. 7. Electron-transfer reactions of indium sulfide semiconductor colloids

    SciTech Connect (OSTI)

    Kamat, P.V.; Dimitrijevic, N.M.; Fessenden, R.W.

    1988-04-21T23:59:59.000Z

    Small semiconductor colloids of In/sub 2/S/sub 3/ have been prepared in aqueous and nonaqueous media and their absorption properties characterized. A transient photobleaching and formation of S/sup .-/ and S/sub 2/H/sub 2//sup .-/ radicals have been observed upon laser pulse (355 nm) excitation of these colloids. With the aid of transient absorption spectra, the anodic corrosion process in these semiconductor colloids has been elucidated by using laser flash photolysis and pulse radiolysis techniques. With the use of a zwitterionic viologen compound, the interfacial charge-transfer process at the semiconductor surface has been studied. The quantum yield for the reduction of zwitterionic viologen was 0.07, which is similar to the value obtained with other metal chalcogenide semiconductor colloids. The microenvironment of the stabilizer (Nafion) influenced the charge-transfer process between the semiconductor and the redox decay.

  1. Physics with isotopically controlled semiconductors

    SciTech Connect (OSTI)

    Haller, E. E., E-mail: eehaller@lbl.gov [University of California at Berkeley, Department of Materials Science and Engineering (United States)

    2010-07-15T23:59:59.000Z

    This paper is based on a tutorial presentation at the International Conference on Defects in Semiconductors (ICDS-25) held in Saint Petersburg, Russia in July 2009. The tutorial focused on a review of recent research involving isotopically controlled semiconductors. Studies with isotopically enriched semiconductor structures experienced a dramatic expansion at the end of the Cold War when significant quantities of enriched isotopes of elements forming semiconductors became available for worldwide collaborations. Isotopes of an element differ in nuclear mass, may have different nuclear spins and undergo different nuclear reactions. Among the latter, the capture of thermal neutrons which can lead to neutron transmutation doping, is the most prominent effect for semiconductors. Experimental and theoretical research exploiting the differences in all the properties has been conducted and will be illustrated with selected examples.

  2. Electrodeposited doped II-VI semiconductor films and devices incorporating such films

    SciTech Connect (OSTI)

    Ondris, M.; Picher, M.A.; Brownfield, R.E.

    1990-03-20T23:59:59.000Z

    This patent describes a photovoltaic device. It comprises: a first thin film of a compound semiconductor of a first conductivity type including tellurium and a metal selected from Group IIB of the Periodic Table of Elements and containing as a dopant impurity in a concentration not exceeding 10{sup 20} atoms per cubic centimeter a metal selected from Group IB, a second semiconductor thin film in contact with the first semiconductor thin film and having a second conductivity type opposite that of the first conductivity type and electrical contacts to each of the first and second semiconductor thin films. Also described is the device wherein the first thin film is p-type cadmium telluride.

  3. 3.225 Electronic and Mechanical Properties of Materials, Summer 2002

    E-Print Network [OSTI]

    Gibson, Lorna J.

    2002-01-01T23:59:59.000Z

    Electrical, optical, magnetic, and mechanical properties of metals, semiconductors, ceramics and polymers. Discussion of roles of bonding, structure (crystalline, defect, energy band and microstructure) and composition in ...

  4. High-Performance Corrosion-Resistant Materials: Iron-Based Amorphous-Metal Thermal-Spray Coatings: SAM HPCRM Program ? FY04 Annual Report ? Rev. 0 - DARPA DSO & DOE OCRWM Co-Sponsored Advanced Materials Program

    SciTech Connect (OSTI)

    Farmer, J; Haslam, J; Wong, F; Ji, S; Day, S; Branagan, D; Marshall, M; Meacham, B; Buffa, E; Blue, C; Rivard, J; Beardsley, M; Buffa, E; Blue, C; Rivard, J; Beardsley, M; Weaver, D; Aprigliano, L; Kohler, L; Bayles, R; Lemieux, E; Wolejsza, T; Martin, F; Yang, N; Lucadamo, G; Perepezko, J; Hildal, K; Kaufman, L; Heuer, A; Ernst, F; Michal, G; Kahn, H; Lavernia, E

    2007-09-19T23:59:59.000Z

    The multi-institutional High Performance Corrosion Resistant Materials (HPCRM) Team is cosponsored by the Defense Advanced Projects Agency (DARPA) Defense Science Office (DSO) and the Department of Energy (DOE) Office of Civilian Radioactive Waste Management (OCRWM), and has developed new corrosion-resistant, iron-based amorphous metals that can be applied as coatings with advanced thermal spray technology. Two compositions have corrosion resistance superior to wrought nickel-based Alloy C-22 (UNS No. N06022) in very aggressive environments, including concentrated calcium-chloride brines at elevated temperature. Corrosion costs the Department of Defense billions of dollars every year, with an immense quantity of material in various structures undergoing corrosion. For example, in addition to fluid and seawater piping, ballast tanks, and propulsions systems, approximately 345 million square feet of structure aboard naval ships and crafts require costly corrosion control measures. The use of advanced corrosion-resistant materials to prevent the continuous degradation of this massive surface area would be extremely beneficial. The Fe-based corrosion-resistant, amorphous-metal coatings under development may prove of importance for applications on ships. Such coatings could be used as an 'integral drip shield' on spent fuel containers, as well as protective coatings that could be applied over welds, thereby preventing exposure to environments that might cause stress corrosion cracking. In the future, such new high-performance iron-based materials could be substituted for more-expensive nickel-based alloys, thereby enabling a reduction in the $58-billion life cycle cost for the long-term storage of the Nation's spent nuclear fuel by tens of percent.

  5. Materials management in an internationally safeguarded fuels reprocessing plant. [1500 and 210 metric tons heavy metal per year

    SciTech Connect (OSTI)

    Hakkila, E.A.; Cobb, D.D.; Dayem, H.A.; Dietz, R.J.; Kern, E.A.; Markin, J.T.; Shipley, J.P.; Barnes, J.W.; Scheinman, L.

    1980-04-01T23:59:59.000Z

    The second volume describes the requirements and functions of materials measurement and accounting systems (MMAS) and conceptual designs for an MMAS incorporating both conventional and near-real-time (dynamic) measurement and accounting techniques. Effectiveness evaluations, based on recently developed modeling, simulation, and analysis procedures, show that conventional accountability can meet IAEA goal quantities and detection times in these reference facilities only for low-enriched uranium. Dynamic materials accounting may meet IAEA goals for detecting the abrupt (1-3 weeks) diversion of 8 kg of plutonium. Current materials accounting techniques probably cannot meet the 1-y protracted-diversion goal of 8 kg for plutonium.

  6. Hardfacing material

    DOE Patents [OSTI]

    Branagan, Daniel J. (Iona, ID)

    2012-01-17T23:59:59.000Z

    A method of producing a hard metallic material by forming a mixture containing at least 55% iron and at least one of boron, carbon, silicon and phosphorus. The mixture is formed into an alloy and cooled to form a metallic material having a hardness of greater than about 9.2 GPa. The invention includes a method of forming a wire by combining a metal strip and a powder. The metal strip and the powder are rolled to form a wire containing at least 55% iron and from two to seven additional elements including at least one of C, Si and B. The invention also includes a method of forming a hardened surface on a substrate by processing a solid mass to form a powder, applying the powder to a surface to form a layer containing metallic glass, and converting the glass to a crystalline material having a nanocrystalline grain size.

  7. Metal-Air Batteries

    SciTech Connect (OSTI)

    Zhang, Jiguang; Bruce, Peter G.; Zhang, Gregory

    2011-08-01T23:59:59.000Z

    Metal-air batteries have much higher specific energies than most currently available primary and rechargeable batteries. Recent advances in electrode materials and electrolytes, as well as new designs on metal-air batteries, have attracted intensive effort in recent years, especially in the development of lithium-air batteries. The general principle in metal-air batteries will be reviewed in this chapter. The materials, preparation methods, and performances of metal-air batteries will be discussed. Two main metal-air batteries, Zn-air and Li-air batteries will be discussed in detail. Other type of metal-air batteries will also be described.

  8. Novel air electrode for metal-air battery with new carbon material and method of making same

    DOE Patents [OSTI]

    Ross, P.N. Jr.

    1988-06-21T23:59:59.000Z

    This invention relates to a rechargeable battery or fuel cell. More particularly, this invention relates to a novel air electrode comprising a new carbon electrode support material and a method of making same. 3 figs.

  9. New Conducting and Electrically Switching Molecular Materials based on Main Group and Transition Metal Ions Bridged by TCNQ Derivatives 

    E-Print Network [OSTI]

    Zhang, Zhongyue

    2013-05-24T23:59:59.000Z

    The field of molecular electronics has been under investigation by materials scientists for the last two decades, activity that has increased in recent years as their potential to be components in modern quantum computing ...

  10. Ge-on-Si Integrated Photonics: New Tricks from an Old Semiconductor

    E-Print Network [OSTI]

    Jifeng, Liu

    We review recent progress in Ge active photonic devices for electronic-photonic integration on Si, demonstrating new tricks in optoelectronics from this “old” semiconductor material used for the first transistor more than ...

  11. Rapid synthesis and size control of CuInS2 semi-conductor nanoparticle...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    semi-conductor nanoparticles make them attractive materials for use in next-generation photovoltaics. We have prepared CuInS2 nanoparticles from single source precursors via...

  12. Rapid Synthesis and Size Control of CuInS2 Semi-Conductor Nanoparticle...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    semi-conductor nanoparticles make them attractive materials for use in next-generation photovoltaics. We have prepared CuInS2 nanoparticles from single source precursors via...

  13. Growth and characterization of mid-infrared phosphide-based semiconductor diode lasers

    E-Print Network [OSTI]

    Chi, Pei-Chun

    2010-01-01T23:59:59.000Z

    A diode laser emitting at mid-infrared wavelength (2~5 pm) is an ideal light source for petrochemical or industrial-important gas sensing. Antimony-based III-V compound semiconductor material is the most prominent pseudomorphic ...

  14. Optical Fiber Chemical Sensor with Sol-Gel Derived Refractive Material as Transducer for High Temperature Gas Sensing in Clean Coal Technology

    SciTech Connect (OSTI)

    Shiquan Tao

    2006-12-31T23:59:59.000Z

    The chemistry of sol-gel derived silica and refractive metal oxide has been systematically studied. Sol-gel processes have been developed for preparing porous silica and semiconductor metal oxide materials. Micelle/reversed micelle techniques have been developed for preparing nanometer sized semiconductor metal oxides and noble metal particles. Techniques for doping metal ions, metal oxides and nanosized metal particles into porous sol-gel material have also been developed. Optical properties of sol-gel derived materials in ambient and high temperature gases have been studied by using fiber optic spectroscopic techniques, such as fiber optic ultraviolet/visible absorption spectrometry, fiber optic near infrared absorption spectrometry and fiber optic fluorescence spectrometry. Fiber optic spectrometric techniques have been developed for investigating the optical properties of these sol-gel derived materials prepared as porous optical fibers or as coatings on the surface of silica optical fibers. Optical and electron microscopic techniques have been used to observe the microstructure, such as pore size, pore shape, sensing agent distribution, of sol-gel derived material, as well as the size and morphology of nanometer metal particle doped in sol-gel derived porous silica, the nature of coating of sol-gel derived materials on silica optical fiber surface. In addition, the chemical reactions of metal ion, nanostructured semiconductor metal oxides and nanometer sized metal particles with gas components at room temperature and high temperatures have also been investigated with fiber optic spectrometric methods. Three classes of fiber optic sensors have been developed based on the thorough investigation of sol-gel chemistry and sol-gel derived materials. The first group of fiber optic sensors uses porous silica optical fibers doped with metal ions or metal oxide as transducers for sensing trace NH{sub 3} and H{sub 2}S in high temperature gas samples. The second group of fiber optic sensors uses sol-gel derived porous silica materials doped with nanometer particles of noble metals in the form of fiber or coating for sensing trace H{sub 2}, NH{sub 3} and HCl in gas samples at for applications ambient temperature. The third classes of fiber optic sensors use sol-gel derived semiconductor metal oxide coating on the surface of silica optical fiber as transducers for selectively sensing H{sub 2}, CH{sub 4} and CO at high temperature. In addition, optical fiber temperature sensors use the fluorescence signal of rare-earth metal ions doped porous silica optical fiber or the optical absorption signal of thermochromic metal oxide materials coated on the surface of silica optical fibers have also been developed for monitoring gas temperature of corrosive gas. Based on the results obtained from this project, the principle of fiber optic sensor techniques for monitoring matrix gas components as well as trace components of coal gasification derived syngas has been established. Prototype sensors for sensing trace ammonia and hydrogen sulfide in gasification derived syngas have been built up in our laboratory and have been tested using gas samples with matrix gas composition similar to that of gasification derived fuel gas. Test results illustrated the feasibility of these sensors for applications in IGCC processes.

  15. Semiconductor Bridge Cable Test

    SciTech Connect (OSTI)

    KING, TONY L.

    2002-01-01T23:59:59.000Z

    The semiconductor bridge (SCB) is an electroexplosive device used to initiate detonators. A C cable is commonly used to connect the SCB to a firing set. A series of tests were performed to identify smaller, lighter cables for firing single and multiple SCBs. This report provides a description of these tests and their results. It was demonstrated that lower threshold voltages and faster firing times can be achieved by increasing the wire size, which reduces ohmic losses. The RF 100 appears to be a reasonable substitute for C cable when firing single SCBs. This would reduce the cable volume by 68% and the weight by 67% while increasing the threshold voltage by only 22%. In general, RG 58 outperforms twisted pair when firing multiple SCBs in parallel. The RG 58's superior performance is attributed to its larger conductor size.

  16. A new family of metal chalogenide thin film electrodes for photoelectrochemical applications

    SciTech Connect (OSTI)

    Rajeshwar, K.; Tacconi, N.R. de [Univ. of Texas, Arlington, TX (United States)

    1996-10-01T23:59:59.000Z

    A new family of metal/semiconductor electrocomposite photoelectrodes is described for photoelectrochemical (PEC) applications. These electrocomposites are prepared from an aqueous dispersion containing the targeted metal (in ionic form) and the semiconductor particles. Electrodeposition of the metal affords a matrix in which the semiconductor particles are occluded. This approach is illustrated for nickel/TiO{sub 2} and nickel/CdS model candidates. The influence of preparation variables (deposition potential, temperature, pH, semiconductor content) on the PEC behavior is described.

  17. Photoacoustic measurement of bandgaps of thermoelectric materials

    E-Print Network [OSTI]

    Ni, George (George Wei)

    2014-01-01T23:59:59.000Z

    Thermoelectric materials are a promising class of direct energy conversion materials, usually consisting of highly doped semiconductors. The key to maximizing their thermal to electrical energy conversion lies in optimizing ...

  18. A proposal for Coulomb assisted laser cooling of piezoelectric semiconductors

    SciTech Connect (OSTI)

    Nia, Iman Hassani; Mohseni, Hooman, E-mail: hmohseni@ece.northwestern.edu [Bio-Inspired Sensors and Optoelectronics Laboratory (BISOL), Department of Electrical Engineering, Northwestern University, Evanston, Illinois 60208 (United States)

    2014-07-28T23:59:59.000Z

    Anti-Stokes laser cooling of semiconductors as a compact and vibration-free method is very attractive. While it has achieved significant milestones, increasing its efficiency is highly desirable. The main limitation is the lack of the pristine material quality with high luminescence efficiency. Here, we theoretically demonstrate that the Coulomb interaction among electrons and holes in piezoelectric heterostructures could lead to coherent damping of acoustic phonons; rendering a significantly higher efficiency that leads to the possibility of cooling a broad range of semiconductors.

  19. Controlled Chemical Doping of Semiconductor Nanocrystals Using Redox Buffers

    SciTech Connect (OSTI)

    Engel, Jesse H.; Surendranath, Yogesh; Alivisatos, Paul

    2013-07-09T23:59:59.000Z

    Semiconductor nanocrystal solids are attractive materials for active layers in next-generation optoelectronic devices; however, their efficient implementation has been impeded by the lack of precise control over dopant concentrations. Herein we demonstrate a chemical strategy for the controlled doping of nanocrystal solids under equilibrium conditions. Exposing lead selenide nanocrystal thin films to solutions containing varying proportions of decamethylferrocene and decamethylferrocenium incrementally and reversibly increased the carrier concentration in the solid by 2 orders of magnitude from their native values. This application of redox buffers for controlled doping provides a new method for the precise control of the majority carrier concentration in porous semiconductor thin films.

  20. FY 2008 Progress Report for Lightweighting Materials - 3. Automotive...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    8 Progress Report for Lightweighting Materials - 3. Automotive Metals-Cast FY 2008 Progress Report for Lightweighting Materials - 3. Automotive Metals-Cast Lightweighting Materials...

  1. Organo Luminescent semiconductor nanocrystal probes for biological applications and process for making and using such probes

    DOE Patents [OSTI]

    Weiss, Shimon (Pinole, CA); Bruchez, Jr., Marcel (Albany, CA); Alivisatos, Paul (Oakland, CA)

    1999-01-01T23:59:59.000Z

    A luminescent semiconductor nanocrystal compound is described which is capable of linking to an affinity molecule. The compound comprises (1) a semiconductor nanocrystal capable of emitting electromagnetic radiation (luminescing) in a narrow wavelength band and/or absorbing energy, and/or scattering or diffracting electromagnetic radiation--when excited by an electromagnetic radiation source (of narrow or broad bandwidth) or a particle beam; and (2) at least one linking agent, having a first portion linked to the semiconductor nanocrystal and a second portion capable of linking to an affinity molecule. The luminescent semiconductor nanocrystal compound is linked to an affinity molecule to form an organo luminescent semiconductor nanocrystal probe capable of bonding with a detectable substance in a material being analyzed, and capable of emitting electromagnetic radiation in a narrow wavelength band and/or absorbing, scattering, or diffracting energy when excited by an electromagnetic radiation source (of narrow or broad bandwidth) or a particle beam. The probe is stable to repeated exposure to light in the presence of oxygen and/or other radicals. Further described is a process for making the luminescent semiconductor nanocrystal compound and for making the organo luminescent semiconductor nanocrystal probe comprising the luminescent semiconductor nanocrystal compound linked to an affinity molecule capable of bonding to a detectable substance. A process is also described for using the probe to determine the presence of a detectable substance in a material.

  2. Electrical transport properties of (BN)-rich hexagonal (BN)C semiconductor alloys

    SciTech Connect (OSTI)

    Uddin, M. R.; Doan, T. C.; Li, J.; Lin, J. Y.; Jiang, H. X., E-mail: hx.jiang@ttu.edu [Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, TX 79409 (United States); Ziemer, K. S. [Department of Chemical Engineering, Northeastern University, Boston, MA 02115 (United States)

    2014-08-15T23:59:59.000Z

    The layer structured hexagonal boron nitride carbon semiconductor alloys, h-(BN)C, offer the unique abilities of bandgap engineering (from 0 for graphite to ?6.4 eV for h-BN) and electrical conductivity control (from semi-metal for graphite to insulator for undoped h-BN) through alloying and have the potential to complement III-nitride wide bandgap semiconductors and carbon based nanostructured materials. Epilayers of (BN)-rich h-(BN){sub 1-x}(C{sub 2}){sub x} alloys were synthesized by metal-organic chemical vapor deposition (MOCVD) on (0001) sapphire substrates. Hall-effect measurements revealed that homogeneous (BN)-rich h-(BN){sub 1-x}(C{sub 2}){sub x} alloys are naturally n-type. For alloys with x = 0.032, an electron mobility of about 20 cm{sup 2}/Vs at 650?°K was measured. X-ray photoelectron spectroscopy (XPS) was used to determine the chemical composition and analyze chemical bonding states. Both composition and chemical bonding analysis confirm the formation of alloys. XPS results indicate that the carbon concentration in the alloys increases almost linearly with the flow rate of the carbon precursor (propane (C{sub 3}H{sub 8})) employed during the epilayer growth. XPS chemical bonding analysis showed that these MOCVD grown alloys possess more C-N bonds than C-B bonds, which possibly renders the undoped h-(BN){sub 1-x}(C{sub 2}){sub x} alloys n-type and corroborates the Hall-effect measurement results.

  3. Microbially-mediated method for synthesis of non-oxide semiconductor nanoparticles

    DOE Patents [OSTI]

    Phelps, Tommy J.; Lauf, Robert J.; Moon, Ji Won; Rondinone, Adam J.; Love, Lonnie J.; Duty, Chad Edward; Madden, Andrew Stephen; Li, Yiliang; Ivanov, Ilia N.; Rawn, Claudia Jeanette

    2014-06-24T23:59:59.000Z

    The invention is directed to a method for producing non-oxide semiconductor nanoparticles, the method comprising: (a) subjecting a combination of reaction components to conditions conducive to microbially-mediated formation of non-oxide semiconductor nanoparticles, wherein said combination of reaction components comprises i) anaerobic microbes, ii) a culture medium suitable for sustaining said anaerobic microbes, iii) a metal component comprising at least one type of metal ion, iv) a non-metal component containing at least one non-metal selected from the group consisting of S, Se, Te, and As, and v) one or more electron donors that provide donatable electrons to said anaerobic microbes during consumption of the electron donor by said anaerobic microbes; and (b) isolating said non-oxide semiconductor nanoparticles, which contain at least one of said metal ions and at least one of said non-metals. The invention is also directed to non-oxide semiconductor nanoparticle compositions produced as above and having distinctive properties.

  4. Mathematical Modeling of Semiconductor Devices

    E-Print Network [OSTI]

    Jüngel, Ansgar

    fibers. · Optoelectronic emitters convert an electronic signal into light. Examples are light-emitting diodes (LED) used in displays and indication lambs and semiconductor lasers used in compact disk systems

  5. Modeling the semiconductor industry dynamics

    E-Print Network [OSTI]

    Wu, Kailiang

    2008-01-01T23:59:59.000Z

    The semiconductor industry is an exciting and challenging industry. Strong demand at the application end, plus the high capital intensity and rapid technological innovation in manufacturing, makes it difficult to manage ...

  6. Metals 2000

    SciTech Connect (OSTI)

    Allison, S.W.; Rogers, L.C.; Slaughter, G. [Oak Ridge National Lab., TN (United States); Boensch, F.D. [6025 Oak Hill Lane, Centerville, OH (United States); Claus, R.O.; de Vries, M. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States)

    1993-05-01T23:59:59.000Z

    This strategic planning exercise identified and characterized new and emerging advanced metallic technologies in the context of the drastic changes in global politics and decreasing fiscal resources. In consideration of a hierarchy of technology thrusts stated by various Department of Defense (DOD) spokesmen, and the need to find new and creative ways to acquire and organize programs within an evolving Wright Laboratory, five major candidate programs identified are: C-17 Flap, Transport Fuselage, Mach 5 Aircraft, 4.Fighter Structures, and 5. Missile Structures. These results were formed by extensive discussion with selected major contractors and other experts, and a survey of advanced metallic structure materials. Candidate structural applications with detailed metal structure descriptions bracket a wide variety of uses which warrant consideration for the suggested programs. An analysis on implementing smart skins and structures concepts is given from a metal structures perspective.

  7. Materials Science and Engineering A 483484 (2008) 607610 Indentation creep study on a Zr-based bulk metallic

    E-Print Network [OSTI]

    Gubicza, Jenõ

    2008-01-01T23:59:59.000Z

    to the formation of a quasicrystalline phase. Indentation creep tests were carried out isothermally at the same size quasicrystalline particles on the creep behavior is studied by indentation test. There are onlyMaterials Science and Engineering A 483­484 (2008) 607­610 Indentation creep study on a Zr

  8. OPTICAL AND DYNAMIC PROPERTIES OF UNDOPED AND DOPED SEMICONDUCTOR NANOSTRUCTURES

    SciTech Connect (OSTI)

    Grant, C D; Zhang, J Z

    2007-09-28T23:59:59.000Z

    This chapter provides an overview of some recent research activities on the study of optical and dynamic properties of semiconductor nanomaterials. The emphasis is on unique aspects of these properties in nanostructures as compared to bulk materials. Linear, including absorption and luminescence, and nonlinear optical as well as dynamic properties of semiconductor nanoparticles are discussed with focus on their dependence on particle size, shape, and surface characteristics. Both doped and undoped semiconductor nanomaterials are highlighted and contrasted to illustrate the use of doping to effectively alter and probe nanomaterial properties. Some emerging applications of optical nanomaterials are discussed towards the end of the chapter, including solar energy conversion, optical sensing of chemicals and biochemicals, solid state lighting, photocatalysis, and photoelectrochemistry.

  9. Universal alignment of hydrogen levels in semiconductors and insulators

    E-Print Network [OSTI]

    Van de Walle, C G

    2006-01-01T23:59:59.000Z

    including nitride semiconductors and transparent oxides.and C. G. Van de Walle, in Hydrogen in SemiconductorsII, Semiconductors and Semimetals Vol. 61, edited by N. H.

  10. Identifying semiconductors by d.c. ionization conductivity

    E-Print Network [OSTI]

    2006-01-01T23:59:59.000Z

    expected from high-Z semiconductor detectors? ,” IEEE Transand binary compound semiconductors and insulators,” J PhysIdentifying Semiconductors by D.C. Ionization Conductivity

  11. Semiconductor Quantum Rods as Single Molecule Fluorescent Biological Labels

    E-Print Network [OSTI]

    2006-01-01T23:59:59.000Z

    Alivisatos, A.P. Semiconductor nanocrystas for biologicalemission from colloidal semiconductor quantum rods. ScienceLight amplification in semiconductor nanocrystals: Quantum

  12. Isovalent Anion Substitution in Ga-Mn-pnictide Ferromagnetic Semiconductors

    E-Print Network [OSTI]

    Stone, Peter

    2010-01-01T23:59:59.000Z

    63. O. Madelung, Semiconductors - Basic Data, 2nd Ed. (in Laser Annealing of Semiconductors, edited by J. M. PoateProperties of Semiconductors ("Atom" Publ. House, Moscow,

  13. alternative perovskite materials: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    rays is used. Photovoltaics currently relies on three technologies. Monocrystalline and polycrystalline cells are silicon-based. Thin-film cells use semi-conductor materials....

  14. alternative materials wascon: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    rays is used. Photovoltaics currently relies on three technologies. Monocrystalline and polycrystalline cells are silicon-based. Thin-film cells use semi-conductor materials....

  15. alternative backfill materials: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    rays is used. Photovoltaics currently relies on three technologies. Monocrystalline and polycrystalline cells are silicon-based. Thin-film cells use semi-conductor materials....

  16. alternative refractory materials: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    rays is used. Photovoltaics currently relies on three technologies. Monocrystalline and polycrystalline cells are silicon-based. Thin-film cells use semi-conductor materials....

  17. alternative starting materials: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    rays is used. Photovoltaics currently relies on three technologies. Monocrystalline and polycrystalline cells are silicon-based. Thin-film cells use semi-conductor materials....

  18. alternative target material: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    rays is used. Photovoltaics currently relies on three technologies. Monocrystalline and polycrystalline cells are silicon-based. Thin-film cells use semi-conductor materials....

  19. Cathode material for lithium batteries

    DOE Patents [OSTI]

    Park, Sang-Ho; Amine, Khalil

    2013-07-23T23:59:59.000Z

    A method of manufacture an article of a cathode (positive electrode) material for lithium batteries. The cathode material is a lithium molybdenum composite transition metal oxide material and is prepared by mixing in a solid state an intermediate molybdenum composite transition metal oxide and a lithium source. The mixture is thermally treated to obtain the lithium molybdenum composite transition metal oxide cathode material.

  20. Thin-film solar cell fabricated on a flexible metallic substrate

    DOE Patents [OSTI]

    Tuttle, John R.; Noufi, Rommel; Hasoon, Falah S.

    2006-05-30T23:59:59.000Z

    A thin-film solar cell (10) is provided. The thin-film solar cell (10) comprises a flexible metallic substrate (12) having a first surface and a second surface. A back metal contact layer (16) is deposited on the first surface of the flexible metallic substrate (12). A semiconductor absorber layer (14) is deposited on the back metal contact. A photoactive film deposited on the semiconductor absorber layer (14) forms a heterojunction structure and a grid contact (24) deposited on the heterjunction structure. The flexible metal substrate (12) can be constructed of either aluminium or stainless steel. Furthermore, a method of constructing a solar cell is provided. The method comprises providing an aluminum substrate (12), depositing a semiconductor absorber layer (14) on the aluminum substrate (12), and insulating the aluminum substrate (12) from the semiconductor absorber layer (14) to inhibit reaction between the aluminum substrate (12) and the semiconductor absorber layer (14).