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1

Narrow band gap amorphous silicon semiconductors  

DOE Patents [OSTI]

Disclosed is a narrow band gap amorphous silicon semiconductor comprising an alloy of amorphous silicon and a band gap narrowing element selected from the group consisting of Sn, Ge, and Pb, with an electron donor dopant selected from the group consisting of P, As, Sb, Bi and N. The process for producing the narrow band gap amorphous silicon semiconductor comprises the steps of forming an alloy comprising amorphous silicon and at least one of the aforesaid band gap narrowing elements in amount sufficient to narrow the band gap of the silicon semiconductor alloy below that of amorphous silicon, and also utilizing sufficient amounts of the aforesaid electron donor dopant to maintain the amorphous silicon alloy as an n-type semiconductor.

Madan, A.; Mahan, A.H.

1985-01-10T23:59:59.000Z

2

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

SciTech Connect (OSTI)

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.

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

2009-06-07T23:59:59.000Z

3

Analytical descriptions of the band structure of direct-band-gap zinc-blende-structure semiconductors in the k?p Kane model  

Science Journals Connector (OSTI)

In the framework of the well-known k?p Kane band theory, accurate analytical approximations of conduction- and valence-band dispersion of direct-band-gap zinc-blende-structure semiconductors are derived when the spin-orbit-splitting energy does not exceed the band-gap energy. These approximations include the interactions with the remote bands. The expressions of the eigenfunctions are also obtained. The present analysis elucidates and unifies previous analytical band descriptions.

H.-J. Drouhin and J. Peretti

1991-10-15T23:59:59.000Z

4

Conductivity and optical band gaps of polyethylene oxide doped with Li{sub 2}SO{sub 4} salt  

SciTech Connect (OSTI)

The conductivity and optical properties of Li{sub 2}SO{sub 4} doped polyethylene oxide (PEO) films were studied. The polymer electrolyte films are prepared using solution casting technique. The material phase change was confirmed by X-ray diffraction (XRD) technique. Optical absorption study was conducted using UV- Vis. Spectroscopy in the wavelength range 190–1100nm on pure and doped PEO films. The direct and indirect optical band gaps were found decreased from 5.81–4.51eV and 4.84–3.43eV respectively with increasing the Li{sub 2}SO{sub 4}. The conductivity found to increases with increasing the dopant concentration due to strong hopping mechanism at room temperature.

Chapi, Sharanappa, E-mail: dehu2010@gmail.com; Raghu, S., E-mail: dehu2010@gmail.com; Subramanya, K., E-mail: dehu2010@gmail.com; Archana, K., E-mail: dehu2010@gmail.com; Mini, V., E-mail: dehu2010@gmail.com; Devendrappa, H., E-mail: dehu2010@gmail.com [Dept. of Physics, Mangalore University, Mangalagangothri-574199 (India)

2014-04-24T23:59:59.000Z

5

Substrate-Induced Band-Gap Opening in Epitaxial Graphene  

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

Substrate-Induced Band-Gap Opening in Epitaxial Graphene Print Prospective challengers to silicon, the long-reigning king of semiconductors for computer chips and other electronic...

6

Fabrication of photonic band gap materials  

DOE Patents [OSTI]

A method for forming a periodic dielectric structure exhibiting photonic band gap effects includes forming a slurry of a nano-crystalline ceramic dielectric or semiconductor material and monodisperse polymer microspheres, depositing a film of the slurry on a substrate, drying the film, and calcining the film to remove the polymer microspheres therefrom. The film may be cold-pressed after drying and prior to calcining. The ceramic dielectric or semiconductor material may be titania, and the polymer microspheres may be polystyrene microspheres.

Constant, Kristen (Ames, IA); Subramania, Ganapathi S. (Ames, IA); Biswas, Rana (Ames, IA); Ho, Kai-Ming (Ames, IA)

2002-01-15T23:59:59.000Z

7

Electronic materials with a wide band gap: recent developments  

Science Journals Connector (OSTI)

Usually, semiconductors with a band gap Eg 3 eV or larger are called wide band gap materials. Their optical emission can span the whole of the visible spectrum, enabling the development of devices for solid-state lighting. In addition, a large Eg results in a high electrical breakthrough field, which is interesting for high-power electronics.

Klimm, D.

2014-08-29T23:59:59.000Z

8

Adaptive algorithms for QCSE optical modulators Excitonic optical absorption at near band gap photon energies in III-V compound semiconductor  

E-Print Network [OSTI]

. Typically, such designs make use of simple rectangular potential wells in the AlGaAs/GaAs or InP/InGaAsP1 Adaptive algorithms for QCSE optical modulators Excitonic optical absorption at near band gap of the quantum well, the excitonic optical absorption strength and energy can be manipulated. This quantum

Levi, Anthony F. J.

9

Substrate-Induced Band-Gap Opening in Epitaxial Graphene  

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

Substrate-Induced Band-Gap Opening in Epitaxial Graphene Print Substrate-Induced Band-Gap Opening in Epitaxial Graphene Print Prospective challengers to silicon, the long-reigning king of semiconductors for computer chips and other electronic devices, have to overcome silicon's superb collection of materials properties as well as sophisticated fabrication technologies refined by six decades of effort by materials scientists and engineers. Graphene, one of the latest contenders, has a rather impressive list of features of its own but has lacked a key characteristic of all semiconductors, an energy gap (band gap) in its electronic band structure. A multi-institutional collaboration under the leadership of researchers with Berkeley Lab and the University of California, Berkeley, have now demonstrated that growing an epitaxial film of graphene on a silicon carbide substrate results in a significant band gap, 0.26 electron volts (eV), an important step toward making graphene useful as a semiconductor.

10

Substrate-Induced Band-Gap Opening in Epitaxial Graphene  

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

Substrate-Induced Band-Gap Opening in Epitaxial Graphene Print Substrate-Induced Band-Gap Opening in Epitaxial Graphene Print Prospective challengers to silicon, the long-reigning king of semiconductors for computer chips and other electronic devices, have to overcome silicon's superb collection of materials properties as well as sophisticated fabrication technologies refined by six decades of effort by materials scientists and engineers. Graphene, one of the latest contenders, has a rather impressive list of features of its own but has lacked a key characteristic of all semiconductors, an energy gap (band gap) in its electronic band structure. A multi-institutional collaboration under the leadership of researchers with Berkeley Lab and the University of California, Berkeley, have now demonstrated that growing an epitaxial film of graphene on a silicon carbide substrate results in a significant band gap, 0.26 electron volts (eV), an important step toward making graphene useful as a semiconductor.

11

Preparation of narrow band gap V2O5/TiO2 composite films by micro-arc oxidation  

Science Journals Connector (OSTI)

V2O5/TiO2...composite films were prepared on pure titanium substrates via micro-arc oxidation (MAO) in electrolytes consisting of NaVO3. Their morphology and elements were characterized by scanning electron micro...

Qiang Luo; Xin-wei Li; Qi-zhou Cai…

2012-11-01T23:59:59.000Z

12

PHYSICAL REVIEW B 85, 155101 (2012) Electronic properties of layered multicomponent wide-band-gap oxides: A combinatorial approach  

E-Print Network [OSTI]

PHYSICAL REVIEW B 85, 155101 (2012) Electronic properties of layered multicomponent wide 2012) The structural, electronic, and optical properties of 12 multicomponent oxides with layered self-consistent screened-exchange local density approximation calculations. Strikingly, despite

Medvedeva, Julia E.

13

Low band gap polymers Organic Photovoltaics  

E-Print Network [OSTI]

Low band gap polymers for Organic Photovoltaics Eva Bundgaard Ph.D. Dissertation Risø National Bundgaard Title: Low band gap polymers for Organic photovoltaics Department: The polymer department Report the area of organic photovoltaics are focusing on low band gap polymers, a type of polymer which absorbs

14

Unveiling and controlling the electronic structure of oxidized semiconductor surfaces: Crystalline oxidized InSb(100)(1 × 2)-O  

Science Journals Connector (OSTI)

The exothermic nature of oxidation causes nearly all semiconductor applications in various fields like electronics, medicine, photonics, and sensor technology to acquire an oxidized semiconductor surface part during the application manufacturing. The significance of understanding and controlling the atomic scale properties of oxidized semiconductor surfaces is expected to increase even further with the development of nanoscale semiconductor crystals. The nature of oxidized semiconductor layers is, however, hard to predict and characterize as they are usually buried and amorphous. To shed light on these issues, we pursue a different approach based on oxidized III-V semiconductor layers that are crystalline. We present a comprehensive characterization of oxidized crystalline InSb(100)(1×2)-O layers by ab initio calculations, photoelectron spectroscopy, scanning tunneling microscopy, and spectroscopy, and demonstrate the electronic band structures of different oxidized phases of the semiconductor, which elucidate the previous contradictory semiconductor-oxidation effects. At 0.5 monolayer (ML) oxidation, oxygen atoms tend to occupy subsurface Sb sites, leading to metallic states in the semiconductor band gap, which arise from top dimers. When the oxidation is increased to the 1.0–2.0 ML concentration, oxygen occupies also interstitial sites, and the insulating band structure without gap states is stabilized with unusual occupied In dangling bonds. In contrast, the 2.5–3.0 ML oxide phases undergo significant changes toward a less ordered structure. The findings suggest a methodology for manipulating the electronic structure of oxidized semiconductor layers.

J. J. K. Lång; M. P. J. Punkkinen; M. Tuominen; H.-P. Hedman; M. Vähä-Heikkilä; V. Polojärvi; J. Salmi; V.-M. Korpijärvi; K. Schulte; M. Kuzmin; R. Punkkinen; P. Laukkanen; M. Guina; K. Kokko

2014-07-29T23:59:59.000Z

15

Efficient Band Gap Prediction for Solids  

E-Print Network [OSTI]

An efficient method for the prediction of fundamental band gaps in solids using density functional theory (DFT) is proposed. Generalizing the Delta self-consistent-field (?SCF [delta SCF]) method to infinite solids, the ...

Chan, Maria K.

16

Band-Gap Engineering of Carbon Nanotubes with Grain Boundaries...  

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

Band-Gap Engineering of Carbon Nanotubes with Grain Boundaries. Band-Gap Engineering of Carbon Nanotubes with Grain Boundaries. Abstract: Structure and electronic properties of...

17

Ferromagnetism in Oxide Semiconductors  

SciTech Connect (OSTI)

In order to become a practical technology, semiconductor spintronics requires the discovery and utilization of ferromagnetic semiconductors which exhibit spin polarization in the majority carrier band at and above room temperature. Intrinsic remanent magnetization would allow spin polarized currents to be propagated in such materials without the need for a continuous magnetic field. However, the discovery and understanding of such materials is proving to be a grand challenge in solid-state science. Indeed, one of the 125 critical unanswered scientific questions recently posed in Science magazine asks, “Is it possible to create magnetic semiconductors that work at room temperature?”

Chambers, Scott A.; Droubay, Timothy C.; Wang, Chong M.; Rosso, Kevin M.; Heald, Steve M.; Schwartz, S. A.; Kittilstved, Kevin R.; Gamelin, Daniel R.

2006-11-01T23:59:59.000Z

18

Anomalous Doppler effects in phononic band gaps  

Science Journals Connector (OSTI)

Doppler effects in periodic acoustic media were studied theoretically and experimentally. Analytical formulas are derived using the Green’s function formalism. We found that a far field observer cannot hear the sound inside a band gap from a stationary source, but a moving source can be heard even if the frequency is inside the gap, and the Doppler shifts can be inverted or anomalously large.

Xinhua Hu; Zhihong Hang; Jensen Li; Jian Zi; C. T. Chan

2006-01-30T23:59:59.000Z

19

Substrate-Induced Band-Gap Opening in Epitaxial Graphene  

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

Substrate-Induced Band-Gap Opening in Epitaxial Graphene Substrate-Induced Band-Gap Opening in Epitaxial Graphene Print Wednesday, 26 March 2008 00:00 Prospective challengers to...

20

Significant Reduction in NiO Band Gap upon Formation of LixNi1?xO Alloys: Applications to Solar Energy Conversion  

SciTech Connect (OSTI)

Long-term sustainable solar energy conversion relies on identifying economical and versatile semiconductor materials with appropriate band structures for photovoltaic and photocatalytic applications (e.g., band gaps of ?1.5–2.0 eV). Nickel oxide (NiO) is an inexpensive yet highly promising candidate. Its charge-transfer character may lead to longer carrier lifetimes needed for higher efficiencies, and its conduction band edge is suitable for driving hydrogen evolution via water-splitting. However, NiO’s large band gap (?4 eV) severely limits its use in practical applications. Our first-principles quantum mechanics calculations show band gaps dramatically decrease to ?2.0 eV when NiO is alloyed with Li2O. We show that LixNi1?xO alloys (with x=0.125 and 0.25) are p-type semiconductors, contain states with no impurity levels in the gap and maintain NiO’s desirable charge-transfer character. Lastly, we show that the alloys have potential for photoelectrochemical applications, with band edges well-placed for photocatalytic hydrogen production and CO2 reduction, as well as in tandem dye-sensitized solar cells as a photocathode.

Alidoust, Nima; Toroker, Maytal; Keith, John A.; Carter, Emily A.

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "band-gap semiconductor oxide" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Ideal Soliton Environment Using Parametric Band Gaps  

Science Journals Connector (OSTI)

Simultaneous solitary wave solutions for laser propagation in nonlinear parametric media with up to ( 3+1) dimensions are proved to exist. The combination of the large dispersion of a Bragg grating and the strong nonlinearity of ?(2) optical material results in stable behavior with short interaction distances and low power requirements. The solutions are obtained by using the effective mass approximation to reduce the coupled propagation equations to those describing a dispersive parametric nonlinear waveguide, and are verified by solving the complete set of coupled band-gap equations numerically.

H. He and P. D. Drummond

1997-06-09T23:59:59.000Z

22

Strain-induced band-gap engineering of graphene monoxide and its effect on graphene  

Science Journals Connector (OSTI)

Using first-principles calculations we demonstrate the feasibility of band-gap engineering in two-dimensional crystalline graphene monoxide (GMO), a recently reported graphene-based material with a 1:1 carbon/oxygen ratio. The band gap of GMO, which can be switched between direct and indirect, is tunable over a large range (0–1.35 eV) for accessible strains. Electron and hole transport occurs predominantly along the zigzag and armchair directions (armchair for both) when GMO is a direct- (indirect-) gap semiconductor. A band gap of ?0.5 eV is also induced in graphene at the K? points for GMO/graphene hybrid systems.

H. H. Pu; S. H. Rhim; C. J. Hirschmugl; M. Gajdardziska-Josifovska; M. Weinert; J. H. Chen

2013-02-13T23:59:59.000Z

23

Method for Creating Photonic Band Gap Materials - Energy Innovation...  

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

a photonic band gap. These microstructures have the potential to change the way optoelectronic devices, such as photodiodes, LEDs, and integrated optical circuit elements, are...

24

Comparative study of polyoxometalates and semiconductor metal oxides as catalyst. Photochemical oxidative degradation of thioethers  

SciTech Connect (OSTI)

The photochemical degradation of thioether substrates catalyzed by representative semiconductor metal oxides and sulfides (anatase TiO{sub 2}, SnO{sub 2}, cubic WO{sub 3}, and CdS) and photoredox-active early-transition-metal polyometalates (W{sub 10}O{sub 32}{sup 4{minus}}, PMo{sub 12}O{sub 40}{sup 3{minus}}, PW{sub 12}O{sub 40}{sup 3{minus}}, SiMo{sub 12}O{sub 40}{sup 4{minus}}, PV{sub 2}Mo{sub 10}O{sub 10}{sup 5{minus}}, and P{sub 2}W{sub 18}O{sub 62}{sup 6{minus}}) have been examined under both anaerobic and aerobic conditions. Under anaerobic conditions, all the semiconductors are completely ineffective at photochemically oxidizing or degrading the exemplary thioether substrate tetrahydrothiophene (THT) in the oxidatively resistant solvent acetonitrile. In contrast, all the homogeneous polyoxometalate systems under the same reaction condition, except the neutral tetra-n-butylammonium (Q) salt of PW{sub 12}O{sub 40}{sup 3{minus}}, are quite effective. The latter systems generate products derived from the carbon-based radical {alpha} to the sulfur atom and not sulfoxide or sulfone, the usual products of thioether oxidation by oxometal species. The rate for the most active anaerobic system, that involving the photochemical degradation of THT by Q{sub 4}W{sub 10}O{sub 32}, under optically dilute conditions, is first order in W{sub 10}O{sub 32} {sup 4{minus}} and light intensity and variable order in THT substrate. A rate law consistent with these data is given. Upon addition of O{sub 2}, TiO{sub 2} (with or without Pt(O)) becomes highly active, SnO{sub 2} becomes active, but WO{sub 3} and CdS remain inactive. Reactivity in thioether oxidation is dominated by the interactions of the semiconductors with O{sub 2} and O{sub 2}-derived intermediates; there is no correlation between reactivity and semiconductor band gap. Upon addition of O{sub 2}, all the polyoxometalate systems become more active. 29 refs., 4 figs., 3 tabs.

Chambers, R.C.; Hill, C.L. (Emory Univ., Atlanta, GA (United States))

1991-06-26T23:59:59.000Z

25

Inorganic Graphenylene: A Porous Two-Dimensional Material With Tunable Band Gap  

E-Print Network [OSTI]

By means of ab initio calculations we investigate the possibility of existence of a boron nitride (BN) porous two-dimensional nanosheet which is geometrically similar to the carbon allotrope known as biphenylene carbon. The proposed structure, which we called Inorganic Graphenylene (IGP), is formed spontaneously after selective dehydrogenation of the porous Boron Nitride (BN) structure proposed by Ding et al. We study the structural and electronic properties of both porous BN and IGP and it is shown that, by selective substitution of B and N atoms with carbon atoms in these structures, the band gap can be significantly reduced, changing their behavior from insulators to semiconductors, thus opening the possibility of band gap engineering for this class of two-dimensional materials.

Perim, Eric; Atreto, Pedro Alves da Silva; Galvão, Douglas

2014-01-01T23:59:59.000Z

26

Substrate-induced band gap opening in epitaxial graphene  

E-Print Network [OSTI]

H.A. Electronic states of graphene nanoribbons studied withS.G. Louie. Energy gaps in graphene nanoribbons. Phys. Rev.band-gap engineering of graphene nanoribbons. Phys. Rev.

2008-01-01T23:59:59.000Z

27

Synthesis of electromagnetic modes in photonic band gap fibers  

E-Print Network [OSTI]

In this paper, we report on the successful synthesis of three individual modes, HE11, TEo0, and TE02 for transmission in photonic band gap fibers at near infrared wavelengths. We measure the propagation losses of the HE11 ...

Hu, Qichao

2007-01-01T23:59:59.000Z

28

Oxide Ferromagnetic Semiconductors for Spin-Electronic Transprt  

SciTech Connect (OSTI)

The objective of this research was to investigate the viability of oxide magnetic semiconductors as potential materials for spintronics. We identified some members of the solid solution series of ilmenite (FeTiO3) and hematite (Fe2O3), abbreviated as (IH) for simplicity, for our investigations based on their ferromagnetic and semiconducting properties. With this objective in focus we limited our investigations to the following members of the modified Fe-titanates: IH33 (ilmenitehematite with 33 atomic percent hematite), IH45 (ilmenite-hematite with 45 atomic percent hematite), Mn-substituted ilmenite (Mn-FeTiO3), and Mn-substituted pseudobrookite (Mn- Fe2TiO5). All of them are: 1. wide bandgap semiconductors with band gaps ranging in values between 2.5 to 3.5 eV; 2. n-type semiconductors; 3.they exhibit well defined magnetic hysteresis loops and 4. their magnetic Curie points are greater than 400K. Ceramic, film and single crystal samples were studied and based on their properties we produced varistors (also known as voltage dependent resistors) for microelectronic circuit protection from power surges, three-terminal microelectronic devices capable of generating bipolar currents, and an integrated structured device with controlled magnetic switching of spins. Eleven refereed journal papers, three refereed conference papers and three invention disclosures resulted from our investigations. We also presented invited papers in three international conferences and one national conference. Furthermore two students graduated with Ph.D. degrees, three with M.S. degrees and one with B.S. degree. Also two post-doctoral fellows were actively involved in this research. We established the radiation hardness of our devices in collaboration with a colleague in an HBCU institution, at the Cyclotron Center at Texas A&M University, and at DOE National Labs (Los Alamos and Brookhaven). It is to be appreciated that we met most of our goals and expanded vastly the scope of research by including investigations of Mn-FeTiO3, Mn-Fe2TiO5 and by producing a novel three terminal device capable of generating bipolar currents besides producing radiation resistant varistors and a magnetically switchable device. Furthermore we conclusively established the radiation hardness of the four modified iron titanates we studied. In all our publications, conference and seminar presentations, dissertations and theses sponsorship of DOE has been acknowledged

Dr. R. K. Pandey, Cudworth Endowed Professor (Professor Emeritus of The Unviersity of Alabama)

2008-11-24T23:59:59.000Z

29

Chemical spray pyrolysis deposition and characterization of p-type CuCr1?xMgxO2 transparent oxide semiconductor thin films  

Science Journals Connector (OSTI)

A chemical spray pyrolysis technique for deposition of p-type Mg-doped CuCrO2 transparent oxide semiconductor thin films using metaloorganic precursors is described. As-deposited films contain mixed spinel CuCr2O4 and delafossite CuCrO2 structural phases. Reduction in spinel CuCr2O4 fraction and formation of highly crystalline films with single phase delafossite CuCrO2 structure is realized by annealing at temperatures ?700 °C in argon. A mechanism of synthesis of CuCrO2 films involving precursor decomposition, oxidation and reaction between constituent oxides in the spray deposition process is presented. Post-annealed CuCr0.93Mg0.07O2 thin films show high (?80%) visible transmittance and sharp absorption at band gap energy with direct and indirect optical band gaps 3.11 and 2.58 eV, respectively. Lower (?450 °C) substrate temperature formed films are amorphous and yield lower direct (2.96 eV) and indirect (2.23 eV) band gaps after crystallization. Electrical conductivity of CuCr0.93 Mg0.07O2 thin films ranged 0.6–1 S cm?1 and hole concentration ?2×1019 cm?3 determined from Seebeck analysis. Temperature dependence of conductivity exhibit activation energies ?0.11 eV in 300–470 K and ?0.23 eV in ?470 K region ascribed to activated conduction and grain boundary trap assisted conduction, respectively. Heterojunction diodes of the structure Au/n-(ZnO)/p-(CuCr0.93Mg0.07O2)/SnO2 (TCO) were fabricated which show potential for transparent wide band gap junction device.

S.H. Lim; Suma Desu; A.C. Rastogi

2008-01-01T23:59:59.000Z

30

Method of physical vapor deposition of metal oxides on semiconductors  

DOE Patents [OSTI]

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.

Norton, David P. (Knoxville, TN)

2001-01-01T23:59:59.000Z

31

Band-Gap Engineering of Carbon Nanotubes with Grain Boundaries  

SciTech Connect (OSTI)

Structure and electronic properties of carbon nanotubes (CNTs) with grain boundaries (GBs) are investigated using density-functional calculations, where the GBs parallel and perpendicular to the tube axis are considered. Simulation results show that the GBs have a great effect on the electronic properties of the CNTs. For the GBs along the tube axis, the CNTs are narrow or zero band gap (<0.16 eV) materials, independent of the misorientation angle and diameter. For the GBs perpendicular to the tube axis, localized electronic states appear within the GBs regions, leading to a larger band gap of up to 0.6 eV. It is convenient to transport and localize the electrons and holes by engineering the GBs. These findings are of great significance for developing carbon-based nanomaterials and electronic devices.

Wang, Zhiguo; Zhou, Yungang; Zhang, Yanwen; Gao, Fei

2012-01-26T23:59:59.000Z

32

Band-Gap Engineering of Carbon Nanotubes with Grain Boundaries  

SciTech Connect (OSTI)

Structure and electronic properties of carbon nanotubes (CNTs) with grain boundaries (GBs) are investigated using density-functional calculations, where the GBs parallel and perpendicular to the tube axis are considered. Simulation results show that the GBs have a great effect on the electronic properties of the CNTs. For the GBs along the tube axis, the CNTs are narrow or zero band gap (<0.16 eV) materials, independent of the misoritentaion angle and diameter. For the GBs perpendicular to the tube axis, localized electronic states appear within the GBs regions, leading to a larger band gap of up to 0.6 eV. It is convenient to transport and localize the electrons and holes by engineering the GBs. These findings are of great significance for developing carbon-based nanomaterials and electronic devices.

Wang, Zhiguo [Department of Applied Physics, University of Electronic Science and Technology of China; Zhou, Yungang [Department of Applied Physics, University of Electronic Science and Technology of China; Zhang, Yanwen [ORNL; Gao, Fei [ORNL

2011-01-01T23:59:59.000Z

33

Composition and temperature-induced effects on the phonon spectra of narrow-band-gap Hg1-xCdxTe  

Science Journals Connector (OSTI)

Compositional and temperature-dependent Raman and infrared spectroscopies on the narrow-band-gap II-VI alloy, Hg1-xCdxTe (0?x?0.29), are reported in this paper. Raman measurements over this composition range confirm the two-mode behavior of the optical phonons in the alloy, with the frequency positions exhibiting a monotonic change with the alloy composition x. A resonant enhancement of the HgTe-like forbidden longitudinal-optic mode is observed near the E1 band gap of the alloy. Alloy induced perturbations on the electronic states lead to a smearing and a weakening of the resonance with increasing alloy composition. The optical phonons in this small band-gap alloy exhibit anomalous frequency shifts as a function of temperature vis-à-vis normal wide-band-gap semiconductors. This anomaly is attributed to the strong electron-phonon interaction in narrow-band-gap systems, which overshadows the dominant anharmonic (phonon-phonon) interaction in usual semiconductors. A detailed compositional dependent second-order Raman spectra is also reported.

Shyama Rath, K. P. Jain, S. C. Abbi, C. Julien, and M. Balkanski

1995-12-15T23:59:59.000Z

34

Optical absorption and band gap reduction in (Fe1-xCrx)2O3 solid...  

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

Optical absorption and band gap reduction in (Fe1-xCrx)2O3 solid solutions: A first-principles study. Optical absorption and band gap reduction in (Fe1-xCrx)2O3 solid solutions: A...

35

Electronic structure of Pt based topological Heusler compounds with C1{sub b} structure and 'zero band gap'  

SciTech Connect (OSTI)

Besides of their well-known wide range of properties it was recently shown that many of the heavy Heusler semiconductors with 1:1:1 composition and C1{sub b} structure exhibit a zero band gap behavior and are topological insulators induced by their inverted band structure. In the present study, the electronic structure of the Heusler compounds PtYSb and PtLaBi was investigated by bulk sensitive hard x-ray photoelectron spectroscopy. The measured valence band spectra are clearly resolved and in well agreement to the first-principles calculations of the electronic structure of the compounds. The experimental results give clear evidence for the zero band gap state.

Ouardi, Siham; Shekhar, Chandra; Fecher, Gerhard H.; Kozina, Xeniya; Stryganyuk, Gregory; Felser, Claudia [Institut fuer Anorganische Chemie und Analytische Chemie, Johannes Gutenberg-Universitaet, D-55099 Mainz (Germany); Ueda, Shigenori; Kobayashi, Keisuke [NIMS Beamline Station at SPring-8, National Institute for Materials Science, Hyogo 679-5148 (Japan)

2011-05-23T23:59:59.000Z

36

Lattice Boltzmann model for photonic band gap materials  

Science Journals Connector (OSTI)

An efficient technique for computing photonic band structure and defect modes is proposed based on the lattice Boltzmann model. Physically, it is a scheme based on the kinetics of the virtual microscopic process, rather than a solution of the macroscopic Maxwell equations. The method has significant advantages of being naturally suited for massively parallel machine, as well as speed and convenience, providing another methodology for photonic band gap materials and, also, for general electromagnetic scattering problems in open region when incorporated with the perfectly matched layer technique.

Zhifang Lin; Haiping Fang; Jianjun Xu; Jian Zi; Xiangdong Zhang

2003-02-07T23:59:59.000Z

37

Pseudomorphic GeSn/Ge(001) quantum wells: Examining indirect band gap bowing  

SciTech Connect (OSTI)

A study of the bandgap character of compressively strained GeSn{sub 0.060-0.091}/Ge(001) quantum wells grown by molecular beam epitaxy is reported. The built-in strain in GeSn wells leads to an increased separation between L and {Gamma} conduction band minima. The prevalent indirect interband transitions in GeSn were probed by photoluminescence spectroscopy. As a result we could simulate the L-valley bowing parameter in GeSn alloys, b{sub L} = 0.80 {+-} 0.06 eV at 10 K. From this we conclude that even compressively strained GeSn/Ge(001) alloys could become direct band gap semiconductors at the Sn-fraction higher than 17.0 at. %.

Tonkikh, Alexander A. [Max Planck Institute of Microstructure Physics, Weinberg 2 D-06120, Halle (Saale) (Germany); Institute for Physics of Microstructures RAS, GSP-105, Nizhniy Novgorod (Russian Federation); Eisenschmidt, Christian; Schmidt, Georg [Institute of Physics, Martin Luther University Halle-Wittenberg, Von-Danckelmann-Platz 3 D-01620, Halle (Saale) (Germany); Talalaev, Vadim G. [Max Planck Institute of Microstructure Physics, Weinberg 2 D-06120, Halle (Saale) (Germany); ZIK SiLi-Nano, Martin Luther University Halle-Wittenberg, Karl-Freiherr-von-Fritsch-Str. 3 D-06120, Halle (Saale) (Germany); Zakharov, Nikolay D.; Werner, Peter [Max Planck Institute of Microstructure Physics, Weinberg 2 D-06120, Halle (Saale) (Germany); Schilling, Joerg [ZIK SiLi-Nano, Martin Luther University Halle-Wittenberg, Karl-Freiherr-von-Fritsch-Str. 3 D-06120, Halle (Saale) (Germany)

2013-07-15T23:59:59.000Z

38

Electrical characteristics and thermal stability of HfO{sub 2} metal-oxide-semiconductor capacitors fabricated on clean reconstructed GaSb surfaces  

SciTech Connect (OSTI)

HfO{sub 2}/GaSb interfaces fabricated by high-vacuum HfO{sub 2} deposition on clean reconstructed GaSb surfaces were examined to explore a thermally stable GaSb metal-oxide-semiconductor structure with low interface-state density (D{sub it}). Interface Sb-O bonds were electrically and thermally unstable, and post-metallization annealing at temperatures higher than 200?°C was required to stabilize the HfO{sub 2}/GaSb interfaces. However, the annealing led to large D{sub it} in the upper-half band gap. We propose that the decomposition products that are associated with elemental Sb atoms act as interface states, since a clear correlation between the D{sub it} and the Sb coverage on the initial GaSb surfaces was observed.

Miyata, Noriyuki, E-mail: nori.miyata@aist.go.jp; Mori, Takahiro; Yasuda, Tetsuji [National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568 (Japan); Ohtake, Akihiro [National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044 (Japan); Ichikawa, Masakazu [The University of Tokyo, Tokyo 113-8656 (Japan)

2014-06-09T23:59:59.000Z

39

InAlAs EPITAXIAL GROWTH FOR WIDE BAND GAP SOLAR CELLS Marina S. Leite  

E-Print Network [OSTI]

InAlAs EPITAXIAL GROWTH FOR WIDE BAND GAP SOLAR CELLS Marina S. Leite 1 , Robyn L. Woo 2 , William vapor phase epitaxy and wide band gap solar cell fabrication. X-ray diffraction and transmissionAlAs solar cells lattice-matched to InP were grown and electrically characterized under AM 1.5 global 1-sun

Atwater, Harry

40

Light trapping design for low band-gap polymer solar cells  

E-Print Network [OSTI]

Light trapping design for low band-gap polymer solar cells Stephen Foster1,* and Sajeev John1,2 1 demonstrate numerically a 2-D nanostructured design for light trapping in a low band-gap polymer solar cell, "Light harvesting improvement of organic solar cells with self- enhanced active layer designs," Opt

John, Sajeev

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While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Ternary silicon germanium nitrides: A class of tunable band gap materials  

Science Journals Connector (OSTI)

Ternary silicon germanium nitrides with compositions of both Si1?xGexN and (Si1?xGex)3N4 are predicted to have a band gap that decreases as the germanium:silicon ratio increases. The band gap is indirect for the silicon-rich compounds but becomes direct as the germanium content increases, due to greater mixing of s and p states in the conduction band. This effect of band gap tunability has recently been reported for (Si1?xGex)3N4 in the spinel structure [Boyko et al., Phys. Rev. B 81, 155207 (2010)]. Our results suggest that this is a more general effect and that ternary group-14 nitrides should form a class of semiconducting materials for which the band gap can be tuned by controlling the composition.

Judy N. Hart; Neil L. Allan; Frederik Claeyssens

2011-12-27T23:59:59.000Z

42

Triple photonic band-gap structure dynamically induced in the presence of spontaneously generated coherence  

SciTech Connect (OSTI)

We study a cold atomic sample coherently driven into the five-level triple-{Lambda} configuration for attaining a dynamically controlled triple photonic band-gap structure. Our numerical calculations show that three photonic band gaps with homogeneous reflectivities up to 92% can be induced on demand around the probe resonance by a standing-wave driving field in the presence of spontaneously generated coherence. All these photonic band gaps are severely malformed with probe reflectivities declining rapidly to very low values when spontaneously generated coherence is gradually weakened. The triple photonic band-gap structure can also be attained in a five-level chain-{Lambda} system of cold atoms in the absence of spontaneously generated coherence, which however requires two additional traveling-wave fields to couple relevant levels.

Gao Jinwei; Bao Qianqian; Wan Rengang; Cui Cuili; Wu Jinhui [College of Physics, Jilin University, Changchun 130012 (China)

2011-05-15T23:59:59.000Z

43

Systematic Study of Electronic Phases, Band Gaps and Band Overlaps of Bismuth Antimony Nanowires  

E-Print Network [OSTI]

We have developed an iterative one dimensional model to study the narrow band-gap and the associated non-parabolic dispersion relations for bismuth antimony nanowires. An analytical approximation has also been developed. Based on the general model, we have developed, we have calculated and analyzed the electronic phase diagrams and the band-gap/band-overlap map for bismuth antimony nanowires, as a function of stoichiometry, growth orientation, and wire width.

Shuang Tang; Mildred Dresselhaus

2013-12-03T23:59:59.000Z

44

Generic process for preparing a crystalline oxide upon a group IV semiconductor substrate  

DOE Patents [OSTI]

A process for growing a crystalline oxide epitaxially upon the surface of a Group IV semiconductor, as well as a structure constructed by the process, is described. The semiconductor can be germanium or silicon, and the crystalline oxide can generally be represented by the formula (AO).sub.n (A'BO.sub.3).sub.m in which "n" and "m" are non-negative integer repeats of planes of the alkaline earth oxides or the alkaline earth-containing perovskite oxides. With atomic level control of interfacial thermodynamics in a multicomponent semiconductor/oxide system, a highly perfect interface between a semiconductor and a crystalline oxide can be obtained.

McKee, Rodney A. (Kingston, TN); Walker, Frederick J. (Oak Ridge, TN); Chisholm, Matthew F. (Oak Ridge, TN)

2000-01-01T23:59:59.000Z

45

Band gap and electronic structure of MgSiN{sub 2}  

SciTech Connect (OSTI)

Density functional theory calculations and electron energy loss spectroscopy indicate that the electronic structure of ordered orthorhombic MgSiN{sub 2} is similar to that of wurtzite AlN. A band gap of 5.7?eV was calculated for both MgSiN{sub 2} (indirect) and AlN (direct) using the Heyd-Scuseria-Ernzerhof approximation. Correction with respect to the experimental room-temperature band gap of AlN indicates that the true band gap of MgSiN{sub 2} is 6.2?eV. MgSiN{sub 2} has an additional direct gap of 6.3?eV at the ? point.

Quirk, J. B., E-mail: james.quirk09@imperial.ac.uk; Råsander, M.; McGilvery, C. M.; Moram, M. A. [Department of Materials, Imperial College London, Exhibition Road, London SW7 2AZ (United Kingdom); Palgrave, R. [Department of Chemistry, University College London, Gordon Street WC1H 0AJ (United Kingdom)

2014-09-15T23:59:59.000Z

46

Measurements of CsI band-gap closure to 93 GPa  

Science Journals Connector (OSTI)

Infrared-absorption measurements to a peak pressure of 93 GPa document the pressure-induced closure of the band gap of CsI to about 4450 cm-1 (0.55 eV). In accord with previous spectroscopic measurements to 60 GPa, our data show that the band gap of CsI decreases continuously with pressure, and metallization (complete closure of the gap) is expected to occur above 100 GPa. A recent claim that CsI becomes metallic at 65±5 GPa is therefore spurious.

Quentin Williams and Raymond Jeanloz

1986-01-13T23:59:59.000Z

47

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)

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.

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

48

E-Print Network 3.0 - active complementary metal-oxide-semiconductor...  

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

ion-implanted p and n dopants in germanium Summary: wavelength spectrum allowing optoelectronic integra- tion to enhance complementary-metal-oxide- semiconductor... lim- its in...

49

E-Print Network 3.0 - area metal-oxide-semiconductor electron...  

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

inversion layer mobility Joo-Hiuk Son,a) Seongtae... measured absorption of terahertz radiation pulses by metal-oxide-semiconductor MOS inversion layers... of the...

50

Current transport, gate dielectrics and band gap engineering in graphene devices  

E-Print Network [OSTI]

Current transport, gate dielectrics and band gap engineering in graphene devices Wenjuan Zhu In this work, we studied current transport in mono-, bi- and tri-layer graphene. We find that both of the electrical field of the substrate surface polar phonons in bi-layer/tri-layer graphenes. We also find

Perebeinos, Vasili

51

Metallic photonic-band-gap filament architectures for optimized incandescent lighting Sajeev John and Rongzhou Wang  

E-Print Network [OSTI]

Metallic photonic-band-gap filament architectures for optimized incandescent lighting Sajeev John occur 3,4 . Tra- ditionally incandescent lighting filaments, despite being driven from equilibrium the blackbody spectrum. This suggests the pos- sibility of higher efficiency incandescent lighting, through

John, Sajeev

52

Energy Band-Gap Engineering of Graphene Nanoribbons Melinda Y. Han,1  

E-Print Network [OSTI]

, New York, New York 10027, USA 2 Department of Physics, Columbia University, New York, New York 10027Energy Band-Gap Engineering of Graphene Nanoribbons Melinda Y. Han,1 Barbaros O¨ zyilmaz,2 Yuanbo an energy gap near the charge neutrality point. Individual graphene layers are contacted with metal

Kim, Philip

53

Band gaps in InN/GaN superlattices: Nonpolar and polar growth directions  

SciTech Connect (OSTI)

The electronic structures of nonpolar short-period InN/GaN superlattices (SLs) grown in the wurtzite a- and m-directions have been calculated and compared to previous calculations for polar superlattices (grown in the c-direction). The variation of the band gaps with the composition (m, n) of the mInN/nGaN unit cells of the superlattices was examined. The band structures were obtained by self-consistent calculations based on the local density approximation to the density functional theory using the Linear-Muffin-Tin-Orbital method with a semi-empirical correction for the band gaps. The calculated band gaps and their pressure coefficients for nonpolar superlattices are similar to those calculated for bulk InGaN alloys with an equivalent In/Ga concentration ratio. This is very different from what has been found in polar superlattices where the band gaps are much smaller and vanish when the number m of InN layers in the unit cell exceeds three. A strong internal electric field is responsible for this behavior of polar structures. Experimental photoluminescence data for polar SLs agree very well with gaps calculated for the nonpolar structures. It is suggested that this is caused by screening of the electric field in the polar structures by carriers originating from unintentional defects.

Gorczyca, I., E-mail: iza@unipress.waw.pl; Skrobas, K.; Suski, T. [Institute of High Pressure Physics, UNIPRESS, 01-142 Warsaw (Poland); Christensen, N. E.; Svane, A. [Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark)

2013-12-14T23:59:59.000Z

54

Size effect on the electronic and optical band gap of CdSe QD  

SciTech Connect (OSTI)

Present paper deals with a critical and comprehensive analysis of the dependence of photo emission (PE) electronic band gap and optical absorption (OA) excitonic band gap on the size of CdSe QD, via connecting it with excitonic absorbance wavelength. Excitonic absorbance wavelength is determined through an empirical fit of established experimental evidences. Effective excitonic charge and Bohr radius is determined as a function of size. Increase in size of the CdSe QD results in greater Bohr radius and smaller effective excitonic charge. Excitonic binding energy as a degree of size of QD is also calculated which further relates with the difference in PE electronic and OA optical band gaps. It is also shown that with increase in size of CdSe QD, the excitonic binding energy decreases which consequently increases differences in two band gaps. Our results are very well comparable with the established results. Explanation for the origin of the unusual optical properties of CdSe QD has been also discussed.

Sisodia, Namita, E-mail: namitasisodiya@gmail.com [Department of Physics, Holkar Science College, Indore-45200 (India)

2014-04-24T23:59:59.000Z

55

Forward Raman compression via photonic band gap in metals or warm dense matter  

SciTech Connect (OSTI)

The group velocity of a light pulse in photonic band gap material could considerably deviate from the speed of light in vacuum. A forward stoke and a pump pulse of different speeds would enable the Raman compression in metals or the warm dense matter. A small window of the parameter regime, where the compression is feasible via the forward Raman scattering, is identified.

Son, S. [18 Caleb Lane, Princeton, New Jersey 08540 (United States); Moon, Sung Joon [Program in Applied and Computational Mathematics, Princeton University, Princeton, New Jersey 08544 (United States)

2011-08-15T23:59:59.000Z

56

SPECTROSCOPIE DE DEFAUTS -LUMINESCENCE I. THE ANALYSIS OF WIDE BAND GAP SEMICONDUCTORS  

E-Print Network [OSTI]

'impuretes donneurs, accepteurs et pieges isoelectroniques,et de leur extension a I'identification d'espkces chimiques of impurity, donors, acceptors and isoelectronic traps, and their extension to the identification of chemical junctions with quite heavy doping to provide the desired high bulk conduc- tivity, certainly in the 10'' cm

Boyer, Edmond

57

Defects in wide band gap semiconductors: magneto-optical double resonance studies  

Science Journals Connector (OSTI)

Recent results obtained in the investigation of shallow donors in GaN with optical detection of electron paramagnetic resonance via the so-called yellow luminescence are reviewed as well as recent results on the silicon vacancy in SiC using optical detection of electron paramagnetic resonance via the magnetic circular dichroism of the absorption. The power of these double resonance methods is illustrated. The possibility of electrical detection of electron paramagnetic resonance in the electrical conductivity is also briefly discussed as future development.

Johann-Martin Spaeth

2004-01-01T23:59:59.000Z

58

Recent progress in transparent oxide semiconductors: Materials and device application  

Science Journals Connector (OSTI)

This paper reviews our recent research progress on new transparent conductive oxide (TCO) materials and electronic and optoelectronic devices based on these materials. First, described are the materials including p-type materials, deep-UV transparent TCO(?-Ga2O3), epitaxially grown ITO with atomically flat surface, transparent electrochromic oxide (NbO2F), amorphous TCOs, and nanoporous semiconductor 12CaO · 7Al2O3. Second, presented are TCO-based electronic/optoelectronic devices realized to date, UV/blue LED and UV-sensors based on transparent pn junction and high performance transparent TFT using n-type TCO as an n-channel. Finally, unique optoelectronic properties (p-type degenerate conduction, transfer doping of carriers, RT-stable exciton, and large optical nonlinearity) originating from 2D-electronic nature in p-type layered oxychalcogenides are summarized along with the fabrication method of epitaxial thin films of these materials.

Hideo Hosono

2007-01-01T23:59:59.000Z

59

Planar graphene-narrow-gap semiconductor-graphene heterostructure  

Science Journals Connector (OSTI)

A planar heterostructure composed of two graphene films between which a narrow-gap semiconductor ... paradox is absent when conical points of the graphene Brillouin zone are in the band gap...

P. V. Ratnikov; A. P. Silin

2008-11-01T23:59:59.000Z

60

Electron Beam Source Molecular Beam Epitaxy of AlxGal?xAs Graded Band Gap Device Structures  

Science Journals Connector (OSTI)

A new method has been developed for the growth of graded band-gap AlxGal?xAs alloys by molecular beam epitaxy which is based upon electron. beam evaporation of the Group III elements ... . The large dynamic respo...

R. J. Malik; A. F. J. Levi; B. F. Levine…

1989-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "band-gap semiconductor oxide" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Structural and optical properties of Ag-doped copper oxide thin films on polyethylene napthalate substrate prepared by low temperature microwave annealing  

SciTech Connect (OSTI)

Silver doped cupric oxide thin films are prepared on polyethylene naphthalate (flexible polymer) substrates. Thin films Ag-doped CuO are deposited on the substrate by co-sputtering followed by microwave assisted oxidation of the metal films. The low temperature tolerance of the polymer substrates led to the search for innovative low temperature processing techniques. Cupric oxide is a p-type semiconductor with an indirect band gap and is used as selective absorption layer solar cells. X-ray diffraction identifies the CuO phases. Rutherford backscattering spectrometry measurements confirm the stoichiometry of each copper oxide formed. The surface morphology is determined by atomic force microscopy. The microstructural properties such as crystallite size and the microstrain for (-111) and (111) planes are calculated and discussed. Incorporation of Ag led to the lowering of band gap in CuO. Consequently, it is determined that Ag addition has a strong effect on the structural, morphological, surface, and optical properties of CuO grown on flexible substrates by microwave annealing. Tauc's plot is used to determine the optical band gap of CuO and Ag doped CuO films. The values of the indirect and direct band gap for CuO are found to be 2.02 eV and 3.19 eV, respectively.

Das, Sayantan; Alford, T. L. [Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287, USA and School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona 85287 (United States)] [Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287, USA and School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona 85287 (United States)

2013-06-28T23:59:59.000Z

62

Multi junction solar cells using band-gap induced cascaded light absorption  

Science Journals Connector (OSTI)

We propose multi junction solar cells using an optical reflection system formed by arranging plural solar cells in decreasing order of their band gaps for achieving cascaded light absorption by their own band gaps: the first solar cell absorbs some light with a photon energy higher than the highest band gap and reflects the residual light with a lower photon energy to the second solar cell. We further propose to use plural batteries for charging electrical power generated by the individual solar cells to overcome the current matching problem in the multi-junction solar cells. We experimentally demonstrated reflection-type multi junction solar cells using commercially available hydrogenated amorphous silicon (a-Si:H) and crystalline silicon (c-Si) solar cells using air mass 1.5 light illumination. A high open circuit voltage of 24.3 V was achieved, which was a sum of 19.3 and 5.0 V for the individual a-Si:H and c-Si solar cells. However, since there was no current matching between the a-Si:H and c-Si solar cells, the a-Si:H?c-Si serially connected solar cell gave a maximum power of 0.057 W, which was lower than 0.063 W, the sum of those for the individual a-Si:H and c-Si solar cells. The method of charging electrical power from individual solar cells is useful to efficiently achieve electrical power from individual a-Si:H and c-Si solar cells in the absence of current matching in multi junction solar cells.

Toshiyuki Sameshima; Hitomi Nomura; Shinya Yoshidomi; Masahiko Hasumi

2014-01-01T23:59:59.000Z

63

Photonic band gaps in three-dimensional network structures with short-range order  

SciTech Connect (OSTI)

We present a systematic study of photonic band gaps (PBGs) in three-dimensional (3D) photonic amorphous structures (PASs) with short-range order. From calculations of the density of optical states (DOS) for PASs with different topologies, we find that tetrahedrally connected dielectric networks produce the largest isotropic PBGs. Local uniformity and tetrahedral order are essential to the formation of PBGs in PASs, in addition to short-range geometric order. This work demonstrates that it is possible to create broad, isotropic PBGs for vector light fields in 3D PASs without long-range order.

Liew, Seng Fatt; Noh, Heeso [Department of Applied Physics, Yale University, New Haven, Connecticut 06511 (United States); Yang, Jin-Kyu [Department of Applied Physics, Yale University, New Haven, Connecticut 06511 (United States); Department of Optical Engineering, Kongju National University, Kongju 314-701 (Korea, Republic of); Schreck, Carl F. [Department of Physics, Yale University, New Haven, Connecticut 06511 (United States); Dufresne, Eric R. [Department of Physics, Yale University, New Haven, Connecticut 06511 (United States); Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06511 (United States); Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06511 (United States); Department of Cell Biology, Yale University, New Haven, Connecticut 06511 (United States); O'Hern, Corey S. [Department of Physics, Yale University, New Haven, Connecticut 06511 (United States); Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06511 (United States); Cao, Hui [Department of Applied Physics, Yale University, New Haven, Connecticut 06511 (United States); Department of Physics, Yale University, New Haven, Connecticut 06511 (United States)

2011-12-15T23:59:59.000Z

64

Photovoltages Larger than the Band Gap in Thin Films of Germanium  

Science Journals Connector (OSTI)

Photovoltages much larger than the band gap were investigated in thin films of germanium deposited obliquely onto Pyrex substrates. The voltages were studied as functions of angle of deposit film thickness intensity of illumination temperature and ambient atmosphere. A model is presented which explains the following observations. Positive and negative photovoltages exist simultaneously in a single sample; which of these predominates changes with time. Dark resistance and photovoltage exhibit the same temperature dependence with identical activation energies indicating that both dark resistance and photovoltage arise from the same elementary processes.

H. Kallmann; G. Marmor Spruch; S. Trester

1972-01-01T23:59:59.000Z

65

Is it effective to harvest visible light by decreasing the band gap of photocatalytic materials?  

SciTech Connect (OSTI)

In situ variations in the electron work function and photo-current of TiO{sub 2} nanotubes demonstrate that long-wavelength illumination only has a minor effect on the excitation of electrons in the nanotubes after being exposed to short-wavelength light or when the short-wavelength light coexisted, indicating that the solar spectrum may not be utilized as efficiently as expected by extending the absorption spectrum of the photocatalytic material to visible light range with decreased band gaps.

Fu Ning; Tang Xinhu; Li Dongyang [Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 2G6 (Canada)

2012-02-27T23:59:59.000Z

66

Direct space-time observation of pulse tunneling in an electromagnetic band gap  

SciTech Connect (OSTI)

We present space-time-resolved measurements of electromagnetic pulses tunneling through a coaxial electromagnetic band gap structure. The results show that during the tunneling process the field distribution inside the barrier is an exponentially decaying standing wave whose amplitude increases and decreases as it slowly follows the temporal evolution of the input pulse. At no time is a pulse maximum found inside the barrier, and hence the transmitted peak is not the incident peak that has propagated to the exit. The results support the quasistatic interpretation of tunneling dynamics and confirm that the group delay is not the traversal time of the input pulse peak.

Doiron, Serge; Hache, Alain [Department de physique et d'astronomie, Universite de Moncton, Moncton, New Brunswick, E1A 3E9 (Canada); Winful, Herbert G. [Department of Electrical Engineering and Computer Science, University of Michigan, 1301 Beal Avenue, Ann Arbor, Michigan 48109-2122 (United States)

2007-08-15T23:59:59.000Z

67

Importance of carrier dynamics and conservation of momentum in atom-selective STM imaging and band gap determination of GaAs(110)  

Science Journals Connector (OSTI)

Scanning tunneling microscopy and spectroscopy measurements on the GaAs(110) surface with complementary theoretical calculations are performed to clarify the effects involved in the tunneling of unpinned semiconductor surfaces. We show that the flatband and tip-induced band bending as well as equilibrium conditions are insufficient to describe the effects involved. Instead, carrier dynamics and conservation of momentum of the tunneling electrons need to be taken into account for a complete description of the contributions of the valence or conduction band states. The results allow us to understand the unique properties needed to achieve the atom-selective imaging observed on these surfaces as well as the determination of the band gap energy.

N. D. Jäger, E. R. Weber, K. Urban, and Ph. Ebert

2003-04-29T23:59:59.000Z

68

Photonic-band-gap effects in two-dimensional polycrystalline and amorphous structures  

SciTech Connect (OSTI)

We study numerically the density of optical states (DOS) in two-dimensional photonic structures with short-range positional order and observe a transition from polycrystalline to amorphous photonic systems. In polycrystals, photonic band gaps (PBGs) are formed within individual domains, which leads to a depletion of the DOS similar to that in periodic structures. In amorphous photonic media, the domain sizes are too small to form PBGs, thus the depletion of the DOS is weakened significantly. The critical domain size that separates the polycrystalline and amorphous regimes is determined by the attenuation length of Bragg scattering, which depends not only on the degree of positional order but also the refractive-index contrast of the photonic material. Even with relatively low-refractive-index contrast, we find that modest short-range positional order in photonic structures enhances light confinement via collective scattering and interference.

Yang, Jin-Kyu; Noh, Heeso; Liew, Seng-Fatt [Department of Applied Physics, Yale University, New Haven, Connecticut 06520-8482 (United States); Schreck, Carl [Department of Physics, Yale University, New Haven, Connecticut 06520-8120 (United States); Guy, Mikhael I. [Science and Research Software Core, Yale University, New Haven, Connecticut 06520-8286 (United States); O'Hern, Corey S. [Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06520-8286 (United States); Department of Physics, Yale University, New Haven, Connecticut 06520-8120 (United States); Cao, Hui [Department of Applied Physics, Yale University, New Haven, Connecticut 06520-8482 (United States); Department of Physics, Yale University, New Haven, Connecticut 06520-8120 (United States)

2010-11-15T23:59:59.000Z

69

Stabilization of temperature dependence of band Gap by introducing nitrogen ion into GaInNP alloy  

SciTech Connect (OSTI)

The photoluminescence (PL) spectra of GaInNP are observed to survey the origin of the unique behavior of the band gap caused by incorporating nitrogen ions. The temperature dependence of the PL peak position is carefully analyzed. It is found that the reduction of the temperature alteration owing to the nitrogen incorporation arises from the hybridization between the nitrogen local 3s and 3p orbitals and the conduction band. In the GaInNP and host GaInP with the indium content around 50%, which has a direct band gap slightly lower than an X-valley, the band gap shrinkage with temperature is mediated by an LA phonon at X point.

Emura, Shuichi; Nonoguchi, Shogo; Kim, Kang Min [The Institute of Scientific and Industrial Research, Osaka Univ., Mihogaoka 8-1, Ibaraki, Osaka 567-0047 (Japan)

2013-12-04T23:59:59.000Z

70

More insights into band gap graded a-SiGe:H solar cells by experimental and simulated data  

SciTech Connect (OSTI)

An experimental and numerical study of a-SiGe:H based solar cells with band gap graded i-layer in the shape of a V is presented. The variation of the location of the band gap minimum has strong influence on the solar cell performance. Comparisons of experimental and simulated data of the dark IV-behavior, IV-curves under illumination and the quantum efficiency allow insights into the transport and recombination behavior within the solar cell. The simulations reveal that the position as well as the charge state of the defects determine the device characteristics.

Zimmer, J.; Stiebig, H.; Foelsch, J.; Finger, F.; Eickhoff, T.; Wagner, H.

1997-07-01T23:59:59.000Z

71

Predicting New TiO2 Phases with Low Band Gaps by a Multiobjective Global Optimization Approach  

E-Print Network [OSTI]

stable. This is equivalent to a global optimization problem of a biobjective function, i.e., total energyPredicting New TiO2 Phases with Low Band Gaps by a Multiobjective Global Optimization Approach Hou as a novel global optimization algorithm to predict new polymorphs of bulk TiO2 with better optical

Gong, Xingao

72

Wide-band-gap InAlAs solar cell for an alternative multijunction approach Marina S. Leite,1,a  

E-Print Network [OSTI]

Wide-band-gap InAlAs solar cell for an alternative multijunction approach Marina S. Leite,1,a Robyn L. Woo,2 William D. Hong,2 Daniel C. Law,2 and Harry A. Atwater1 1 California Institute of Technology, 1200 E. California Blvd., Pasadena, California 91125, USA 2 Boeing-Spectrolab Inc., 12500

Atwater, Harry

73

Single-photon imaging in complementary metal oxide semiconductor processes  

Science Journals Connector (OSTI)

...integrated in new materials, e.g. germanium-on-silicon...implemented as an active or as passive...bias of the cathode or the anode...A review of active and passive...voltage at the cathode to follow an...semiconductor material with decreasing...region. The cathode (in this case...whereas active quenching is...

2014-01-01T23:59:59.000Z

74

Transition metal oxides on organic semiconductors Yongbiao Zhao a  

E-Print Network [OSTI]

semiconductors (OSs) structure has been widely used in inverted organic optoelectronic devices, including toward in simplifying the fabrication process of the organic optoelectronic devices. Ã? 2014 Elsevier B], have gained great attention because of their wide applications in optoelectronic devices composed

Demir, Hilmi Volkan

75

Microbially-mediated method for synthesis of non-oxide semiconductor nanoparticles  

DOE Patents [OSTI]

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.

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

76

Designing Semiconductor Metal Oxides for Photoelectrochemical Energy Conversion  

Science Journals Connector (OSTI)

Innovative materials hold the key for renewable energy conversion. In this talk, we will introduce our recent progress in semiconducting metal oxides, which underpin a number of...

Wang, Lianzhou

77

PHYSICAL REVIEW B 90, 115209 (2014) Computational search for direct band gap silicon crystals  

E-Print Network [OSTI]

abundance, silicon is the preferred solar-cell material despite the fact that current silicon materials have semiconductor. For this reason, the most widely used solar-cell materials are all silicon based [1]. Current

Lee, Jooyoung

78

X-Band Photonic Band-Gap Accelerator Structure Breakdown Experiment  

SciTech Connect (OSTI)

In order to understand the performance of photonic band-gap (PBG) structures under realistic high gradient, high power, high repetition rate operation, a PBG accelerator structure was designed and tested at X band (11.424 GHz). The structure consisted of a single test cell with matching cells before and after the structure. The design followed principles previously established in testing a series of conventional pillbox structures. The PBG structure was tested at an accelerating gradient of 65 MV/m yielding a breakdown rate of two breakdowns per hour at 60 Hz. An accelerating gradient above 110 MV/m was demonstrated at a higher breakdown rate. Significant pulsed heating occurred on the surface of the inner rods of the PBG structure, with a temperature rise of 85 K estimated when operating in 100 ns pulses at a gradient of 100 MV/m and a surface magnetic field of 890 kA/m. A temperature rise of up to 250 K was estimated for some shots. The iris surfaces, the location of peak electric field, surprisingly had no damage, but the inner rods, the location of the peak magnetic fields and a large temperature rise, had significant damage. Breakdown in accelerator structures is generally understood in terms of electric field effects. These PBG structure results highlight the unexpected role of magnetic fields in breakdown. The hypothesis is presented that the moderate level electric field on the inner rods, about 14 MV/m, is enhanced at small tips and projections caused by pulsed heating, leading to breakdown. Future PBG structures should be built to minimize pulsed surface heating and temperature rise.

Marsh, Roark A.; /MIT /MIT /NIFS, Gifu /JAERI, Kyoto /LLNL, Livermore; Shapiro, Michael A.; Temkin, Richard J.; /MIT; Dolgashev, Valery A.; Laurent, Lisa L.; Lewandowski, James R.; Yeremian, A.Dian; Tantawi, Sami G.; /SLAC

2012-06-11T23:59:59.000Z

79

Ferromagnetism in Doped Thin-Film Oxide and Nitride Semiconductors and Dielectrics  

SciTech Connect (OSTI)

The principal goal in the field of high-Tc ferromagnetic semiconductors is the synthesis, characterization and utilization of semiconductors which exhibit substantial carrier spin polarization at and above room temperature. Such materials are of critical importance in the emerging field of semiconductor spintronics. The interaction leading to carrier spin polarization, exchange coupling between the dopant spins and the valence or conduction band, is known to be sufficiently weak in conventional semiconductors, such as GaAs and Si, that magnetic ordering above cryogenic temperatures is essentially impossible. Since the provocative theoretical predictions of Tc above ambient in p-Mn:ZnO and p-Mn:GaN (T. Dietl et al., Science 287 1019 (2000)), and the observation of room-temperature ferromagnetism in Co:TiO2 anatase (Y. Matsumoto et al., Science 291 854 (2001)), there has been a flurry of work in oxides and nitrides doped with transition metals with unpaired d electrons. It has even been claimed that room-temperature ferromagnetism can be obtained in certain d0 transition metals oxides without a dopant. In this Report, the field of transition metal doped oxides and nitrides is critically reviewed and assessed from a materials science perspective. Since much of the field centers around thin film growth, this Report focuses on films prepared not only by conventional vacuum deposition methods, but also by spin coating colloidal nanoparticles.

Chambers, Scott A.

2006-10-01T23:59:59.000Z

80

Amorphous hafnium-indium-zinc oxide semiconductor thin film transistors  

Science Journals Connector (OSTI)

We reported on the performance and electrical properties of co-sputtering-processed amorphous hafnium-indium-zinc oxide (?-HfIZO) thin film transistors (TFTs). Co-sputtering-processed ?-HfIZO thin films have shown an amorphous phase in nature. ...

Sheng-Po Chang; San-Syong Shih

2012-01-01T23:59:59.000Z

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81

Thermovoltaic semiconductor device including a plasma filter  

DOE Patents [OSTI]

A thermovoltaic energy conversion device and related method for converting thermal energy into an electrical potential. An interference filter is provided on a semiconductor thermovoltaic cell to pre-filter black body radiation. The semiconductor thermovoltaic cell includes a P/N junction supported on a substrate which converts incident thermal energy below the semiconductor junction band gap into electrical potential. The semiconductor substrate is doped to provide a plasma filter which reflects back energy having a wavelength which is above the band gap and which is ineffectively filtered by the interference filter, through the P/N junction to the source of radiation thereby avoiding parasitic absorption of the unusable portion of the thermal radiation energy.

Baldasaro, Paul F. (Clifton Park, NY)

1999-01-01T23:59:59.000Z

82

Mixed Semiconductor Nanocrystal Compositions  

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

Mixed Semiconductor Nanocrystal Compositions Mixed Semiconductor Nanocrystal Compositions Mixed Semiconductor Nanocrystal Compositions Composition comprising one or more energy donors and one or more energy acceptors. Available for thumbnail of Feynman Center (505) 665-9090 Email Mixed Semiconductor Nanocrystal Compositions Composition comprising one or more energy donors and one or more energy acceptors, wherein energy is transferred from the energy donor to the energy acceptor and wherein: the energy acceptor is a colloidal nanocrystal having a lower band gap energy than the energy donor; the energy donor and the energy acceptor are separated by a distance of 40 nm or less; wherein the average peak absorption energy of the acceptor is at least 20 meV greater than the average peak emission energy of the energy donor; and

83

Emission of Band-Gap-Energy Positrons from Surfaces of LiF, NaF, and Other Ionic Crystals  

Science Journals Connector (OSTI)

Energetic positrons implanted into various ionic crystal surfaces are reemitted with a maximum kinetic energy (14.7 ± 0.7 eV for LiF) near the band-gap energy. The evidence suggests that, at least for LiF and NaF, the emission originates from bulk-formed positronium (Ps) breaking up after diffusing to the surface. In our model, the positrons are Auger emitted when the Ps electrons recombine with holes at the surface, and the spectrum of positron energies thus reflects the density of empty surface states.

A. P. Mills; Jr. and William S. Crane

1984-11-26T23:59:59.000Z

84

Band-Gap Reduction and Dopant Interaction in Epitaxial La,Cr Co-doped SrTiO3 Thin Films  

SciTech Connect (OSTI)

We show that by co-doping SrTiO3 (STO) epitaxial thin films with equal amounts of La and Cr it is possible to produce films with an optical band gap ~0.9 eV lower than that of undoped STO. Sr1-xLaxTi1-xCrxO3 thin films were deposited by molecular beam epitaxy and characterized using x-ray photoelectron spectroscopy and x-ray absorption near-edge spectroscopy to show that the Cr dopants are almost exclusively in the Cr3+ oxidation state. Extended x-ray absorption fine structure measurements and theoretical modeling suggest that it is thermodynamically preferred for La and Cr dopants to occupy nearest neighbor A- and B-sites in the lattice. Transport measurements show that the material exhibits variable-range hopping conductivity with high resistivity. These results create new opportunities for the use of doped STO films in photovoltaic and photocatalytic applications.

Comes, Ryan B.; Sushko, Petr; Heald, Steve M.; Colby, Robert J.; Bowden, Mark E.; Chambers, Scott A.

2014-12-03T23:59:59.000Z

85

Catalytic photooxidation of pentachlorophenol using semiconductor nanoclusters  

SciTech Connect (OSTI)

Pentachlorophenol (PCP) is a toxic chlorinated aromatic molecule widely used as fungicide, a bactericide and a wood preservation, and thus ubiquitous in the environment. The authors report photo-oxidation of PCP using a variety of nanosize semiconductor metal oxides and sulfides in both aqueous and polar organic solvents and compare the photo-oxidation kinetics of these nanoclusters to widely studied bulk powders like Degussa P-25 TiO{sub 2} and CdS. They study both the light intensity dependence of PCP photooxidation for nanosize SnO{sub 2} and the size dependence of PCP photooxidation for both nanosize SnO{sub 2} and MoS{sub 2}. They find an extremely strong size dependence for the latter which they attribute to its size-dependent band gap and the associated change in redox potentials due to quantum confinement of the hole-electron pair. The authors show that nanosize MoS{sub 2} with a diameter of d=3.0 nm and an absorbance edge of {approximately}450 nm is a very effective photooxidation catalyst for complete PCP mineralization, even when using only visible light irradiation.

WILCOXON,JESS P.

2000-04-17T23:59:59.000Z

86

Investigation of the semiconductor–oxide electrolyte interface in GaAs utilizing electrolyte electroreflectance  

Science Journals Connector (OSTI)

We have investigated the electrolyte electroreflectance (EER) spectra of N–GaAs in the vicinity of the E o transition (direct gap at k?=0). A pronounced interference phenomenon sensitive to the d c b i a s e l e c t r i c f i e l d has been observed which we identify with an exciton quenching effect within the semiconductor space–charge region (SCR). We have utilized this excitonic feature to interferometrically probe the dynamic and steady?state properties of the SCR during electrochemical anodization procedures. The same EER spectra also exhibit Franz–Keldysh oscillations the period of which is explicitly dependent on the a c e l e c t r i c f i e l d. Using these phenomena we have shown that the interfacial and oxide electric fields under steady?state conditions are just sufficient to continue growing the oxide in compensation for slow dissolution. If the dc bias voltage is suddenly reduced the SCR temporarily collapses due to transient effects which we attribute to very slow interface states in the oxide. These techniques are applicable to the study of the SCR in a variety of semiconductor–electrolyte systems as well as in the Schottky barrier configuration.

R. P. Silberstein; F. H. Pollak

1980-01-01T23:59:59.000Z

87

Anomalous temperature-dependent band gaps in CuInS2 studied by surface-barrier electroreflectance  

Science Journals Connector (OSTI)

The lowest-energy gaps of CuInS2 have been studied by low-field surface-barrier electroreflectance in the temperature range from 10 to 300 K. Anomalous temperature dependence of E0 and E0+?0 have been found. Below 120 K the temperature coefficient of the band gap is 4.3×10-5 eV/K for E0 and 5.8×10-5 eV/K for E0+?0. Above 120 K the coefficients become -8.7×10-5 eV/K and -4.4×10-5 eV/K for E0 and E0+?0. These temperature-dependent energy gaps are explained by the reduction of d levels in the upper valence band due to thermal expansion and the competition with the electron-phonon interaction. The temperature dependence of spin-orbit splitting in our experiment confirms this explanation.

T. M. Hsu and J. H. Lin

1988-03-15T23:59:59.000Z

88

Photonic band gap in an imperfect atomic diamond lattice: Penetration depth and effects of finite size and vacancies  

Science Journals Connector (OSTI)

We study the effects of finite size and of vacancies on the photonic band gap recently predicted for an atomic diamond lattice. Close to a Jg=0?Je=1 atomic transition, and for atomic lattices containing up to N?3×104 atoms, we show how the density of states can be affected by both the shape of the system and the possible presence of a fraction of unoccupied lattice sites. We numerically predict and theoretically explain the presence of shape-induced border states and of vacancy-induced localized states appearing in the gap. We also investigate the penetration depth of the electromagnetic field which we compare to the case of an infinite system.

Mauro Antezza and Yvan Castin

2013-09-25T23:59:59.000Z

89

Nature of the Band Gap and Origin of the Electro-/Photo-Activity of Co3O4  

SciTech Connect (OSTI)

Co3O4 exhibits intriguing physical, chemical and catalytic properties and has demonstrated great potential for next-generation renewable energy applications. These interesting properties and promising applications are underpinned by its electronic structure and optical properties, which are unfortunately poorly understood and the subject of considerable debate over many years. Here, we unveil a consistent electronic structural description of Co3O4 by synergetic infrared optical and in situ photoemission spectroscopy as well as standard density functional theory calculations. In contrast to previous assumptions, we demonstrate a much smaller fundamental band gap, which is directly related to its efficient electro-/photoactivity. The present results may help to advance the fundamental understanding and provide guidance for the use of oxidematerials in photocatalysis and solar applications.

Qiao, L.; Xiao, Haiyan Y.; Meyer, H. M.; Sun, J. N.; Rouleau, C. M.; Puretzky, A. A.; Geohegan, D. B.; Ivanov, Ilia N.; Yoon, M.; Weber, William J.; Biegalski, Michael D.

2013-08-21T23:59:59.000Z

90

Investigation of anisotropic photonic band gaps in three-dimensional magnetized plasma photonic crystals containing the uniaxial material  

SciTech Connect (OSTI)

In this paper, the dispersive properties of three-dimensional (3D) magnetized plasma photonic crystals (MPPCs) composed of anisotropic dielectric (the uniaxial material) spheres immersed in homogeneous magnetized plasma background with face-centered-cubic (fcc) lattices are theoretically investigated by the plane wave expansion method, as the Voigt effects of magnetized plasma are considered. The equations for calculating the anisotropic photonic band gaps (PBGs) in the first irreducible Brillouin zone are theoretically deduced. The anisotropic PBGs and two flatbands regions can be obtained. The effects of the ordinary-refractive index, extraordinary-refractive index, filling factor, plasma frequency, and external magnetic field on the dispersive properties of the 3D MPPCs are investigated in detail, respectively, and some corresponding physical explanations are also given. The numerical results show that the anisotropy can open partial band gaps in 3D MPPCs with fcc lattices and the complete PBGs can be found compared to the conventional 3D MPPCs doped by the isotropic material. The bandwidths of PBGs can be tuned by introducing the magnetized plasma into 3D PCs containing the uniaxial material. It is also shown that the anisotropic PBGs can be manipulated by the ordinary-refractive index, extraordinary-refractive index, filling factor, plasma frequency, and external magnetic field, respectively. The locations of flatbands regions cannot be manipulated by any parameters except for the plasma frequency and external magnetic field. Introducing the uniaxial material can obtain the complete PBGs as the 3D MPPCs with high symmetry and also provides a way to design the tunable devices.

Zhang, Hai-Feng [College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China) [College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Nanjing Artillery Academy, Nanjing 211132 (China)] [China; Liu, Shao-Bin; Kong, Xiang-Kun [College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China)] [College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China)

2013-09-15T23:59:59.000Z

91

Band-gap nonlinear optical generation: The structure of internal optical field and the structural light focusing  

SciTech Connect (OSTI)

A novel approach for the enhancement of nonlinear optical effects inside globular photonic crystals (PCs) is proposed and systematically studied via numerical simulations. The enhanced optical harmonic generation is associated with two- and three-dimensional PC pumping with the wavelength corresponding to different PC band-gaps. The interactions between light and the PC are numerically simulated using the finite-difference time-domain technique for solving the Maxwell's equations. Both empty and infiltrated two-dimensional PC structures are considered. A significant enhancement of harmonic generation is predicted owing to the highly efficient PC pumping based on the structural light focusing effect inside the PC structure. It is shown that a highly efficient harmonic generation could be attained for both the empty and infiltrated two- and three-dimensional PCs. We are demonstrating the ability for two times enhancement of the parametric decay efficiency, one order enhancement of the second harmonic generation, and two order enhancement of the third harmonic generation in PC structures in comparison to the nonlinear generations in appropriate homogenous media. Obviously, the nonlinear processes should be allowed by the molecular symmetry. The criteria of the nonlinear process efficiency are specified and calculated as a function of pumping wavelength position towards the PC globule diameter. Obtained criterion curves exhibit oscillating characteristics, which indicates that the highly efficient generation corresponds to the various PC band-gap pumping. The highest efficiency of nonlinear conversions could be reached for PC pumping with femtosecond optical pulses; thus, the local peak intensity would be maximized. Possible applications of the observed phenomenon are also discussed.

Zaytsev, Kirill I., E-mail: kirzay@gmail.com; Katyba, Gleb M.; Yakovlev, Egor V.; Yurchenko, Stanislav O., E-mail: st.yurchenko@mail.ru [Bauman Moscow State Technical University, 2nd Baumanskaya str. 5, Moscow 105005 (Russian Federation); Gorelik, Vladimir S. [P. N. Lebedev Physics Institute of the Russian Academy of Sciences, Leninskiy Prospekt 53, Moscow 119991 (Russian Federation)

2014-06-07T23:59:59.000Z

92

Wide band-gap, fairly conductive p-type hydrogenated amorphous silicon carbide films prepared by direct photolysis; solar cell application  

SciTech Connect (OSTI)

Wide optical band-gap (2.0--2.3 eV) undoped and boron-doped hydrogenated amorphous silicon carbide (a-SiC:H) films have been prepared by both direct photo and rf glow discharge (GD plasma) decomposition of pure methylsilanes or acetylene and disilane gas mixtures. The photochemically prepared p-type films showed higher dark conductivities and lower activation energies. For an optical band gap of 2.0 eV a high conductivity of 7.0 x 10/sup -5/ (S cm/sup -1/) and a low activation energy of 0.33 eV have been measured. The first trial of these wide band-gap, fairly conductive films as a window layer in a p-i-n solar cell showed the high conversion efficiency of 9.46% under AM1 insolation.

Yamada, A.; Kenne, J.; Konagai, M.; Takahashi, K.

1985-02-01T23:59:59.000Z

93

Bringing oxides into the visible realm | EMSL  

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

visible realm Bringing oxides into the visible realm Reducing the optical band gap of strontium titanate thin films This is a model of the growth process showing one lanthanum and...

94

Interfacial oxide re-growth in thin film metal oxide III-V semiconductor systems  

SciTech Connect (OSTI)

The Al{sub 2}O{sub 3}/GaAs and HfO{sub 2}/GaAs interfaces after atomic layer deposition are studied using in situ monochromatic x-ray photoelectron spectroscopy. Samples are deliberately exposed to atmospheric conditions and interfacial oxide re-growth is observed. The extent of this re-growth is found to depend on the dielectric material and the exposure temperature. Comparisons with previous studies show that ex situ characterization can result in misleading conclusions about the interface reactions occurring during the metal oxide deposition process.

McDonnell, S.; Dong, H.; Hawkins, J. M.; Brennan, B.; Milojevic, M.; Aguirre-Tostado, F. S.; Zhernokletov, D. M.; Hinkle, C. L.; Kim, J.; Wallace, R. M.

2012-04-02T23:59:59.000Z

95

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

E-Print Network [OSTI]

AlGaN/GaN metal-oxide-semiconductor heterostructure field-effect transistors using barium strontium-effect transistors have been formed by incorporating barium strontium titanate (BST) deposited by rf magnetron in increased leakage. Due to its large dielectric constant, barium strontium ti- tanate [Ba1-xSrxTiO3, (BST

York, Robert A.

96

On the sub-band gap optical absorption in heat treated cadmium sulphide thin film deposited on glass by chemical bath deposition technique  

SciTech Connect (OSTI)

The sub-band gap optical absorption in chemical bath deposited cadmium sulphide thin films annealed at different temperatures has been critically analyzed with special reference to Urbach relation. It has been found that the absorption co-efficient of the material in the sub-band gap region is nearly constant up to a certain critical value of the photon energy. However, as the photon energy exceeds the critical value, the absorption coefficient increases exponentially indicating the dominance of Urbach rule. The absorption coefficients in the constant absorption region and the Urbach region have been found to be sensitive to annealing temperature. A critical examination of the temperature dependence of the absorption coefficient indicates two different kinds of optical transitions to be operative in the sub-band gap region. After a careful analyses of SEM images, energy dispersive x-ray spectra, and the dc current-voltage characteristics, we conclude that the absorption spectra in the sub-band gap domain is possibly associated with optical transition processes involving deep levels and the grain boundary states of the material.

Chattopadhyay, P.; Karim, B.; Guha Roy, S. [Department of Electronic Science, University of Calcutta, 92, A.P.C. Road, Kolkata 700009 (India)

2013-12-28T23:59:59.000Z

97

Solar-driven electrochemically assisted semiconductor-catalyzed iodide ion oxidation. Enhanced efficiency by oxide mixtures  

Science Journals Connector (OSTI)

Oxidation of iodide ion from an air-saturated solution under natural sunlight (900±50 W m?2) on the surfaces of TiO2, ZnO, Fe2O3, MoO3 and CeO2 enhances by 6 to 12-fold on application of a cathodic bias of ?0.2 t...

Chockalingam Karunakaran; Premkumar Anilkumar

2009-09-01T23:59:59.000Z

98

Realization of Spin Gapless Semiconductors: The Heusler Compound Mn2CoAl  

Science Journals Connector (OSTI)

Recent studies have reported an interesting class of semiconductor materials that bridge the gap between semiconductors and half-metallic ferromagnets. These materials, called spin gapless semiconductors, exhibit a band gap in one of the spin channels and a zero band gap in the other and thus allow for tunable spin transport. Here, we report the first experimental verification of the spin gapless magnetic semiconductor Mn2CoAl, an inverse Heusler compound with a Curie temperature of 720 K and a magnetic moment of 2?B. Below 300 K, the compound exhibits nearly temperature-independent conductivity, very low, temperature-independent carrier concentration, and a vanishing Seebeck coefficient. The anomalous Hall effect is comparatively low, which is explained by the symmetry properties of the Berry curvature. Mn2CoAl is not only suitable material for room temperature semiconductor spintronics, the robust spin polarization of the spin gapless semiconductors makes it very promising material for spintronics in general.

Siham Ouardi; Gerhard H. Fecher; Claudia Felser; Jürgen Kübler

2013-03-05T23:59:59.000Z

99

Analysis of photonic band gap in dispersive properties of tunable three-dimensional photonic crystals doped by magnetized plasma  

SciTech Connect (OSTI)

In this paper, the magnetooptical effects in dispersive properties for two types of three-dimensional magnetized plasma photonic crystals (MPPCs) containing homogeneous dielectric and magnetized plasma with diamond lattices are theoretically investigated for electromagnetic (EM) wave based on plane wave expansion (PWE) method, as incidence EM wave vector is parallel to the external magnetic field. The equations for two types of MPPCs with diamond lattices (dielectric spheres immersed in magnetized plasma background or vice versa) are theoretically deduced. The influences of dielectric constant, plasma collision frequency, filling factor, the external magnetic field, and plasma frequency on the dispersive properties for both types of structures are studied in detail, respectively, and some corresponding physical explanations are also given. From the numerical results, it has been shown that the photonic band gaps (PBGs) for both types of MPPCs can be manipulated by plasma frequency, filling factor, the external magnetic field, and the relative dielectric constant of dielectric, respectively. Especially, the external magnetic field can enlarge the PBG for type-2 structure (plasma spheres immersed in dielectric background). However, the plasma collision frequency has no effect on the dispersive properties of two types of three-dimensional MPPCs. The locations of flatbands regions for both types of structures cannot be tuned by any parameters except for plasma frequency and the external magnetic field. The analytical results may be informative and of technical use to design the MPPCs devices.

Zhang HaiFeng [College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Nanjing Artillery Academy, Nanjing 211132 (China); Liu Shaobin; Yang Huan [College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Kong Xiangkun [College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Jiangsu Key Laboratory of Meteorological Observation and Information Processing, Nanjing University of Information Science and Technology, Nanjing 210044 (China)

2013-03-15T23:59:59.000Z

100

The properties of photonic band gaps for three-dimensional plasma photonic crystals in a diamond structure  

SciTech Connect (OSTI)

In this paper, the properties of photonic band gaps (PBGs) for two types of three-dimensional plasma photonic crystals (PPCs) composed of isotropic dielectric and unmagnetized plasma with diamond lattices are theoretically investigated for electromagnetic waves based on a modified plane wave expansion method. The equations for type-1 structure are theoretically deduced, which depend on the diamond lattices realization (dielectric spheres immersed in plasma background). The influences of dielectric constant of dielectric, plasma collision frequency, filling factor, and plasma frequency on PBGs are investigated, respectively, and some corresponding physical explanations and the possible methods to realize the three-dimensional PPCs in experiments are also given. From the numerical results, it has been shown that not only the locations but also the gap/midgap ratios of the PBGs for two types of PPCs can be tuned by plasma frequency, filling factor, and the relative dielectric constant, respectively. However, the plasma collision frequency has no effect on the frequency ranges and gap/midgap ratios of the PBGs for two types of PPCs.

Zhang Haifeng [College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Nanjing Artillery Academy, Nanjing 211132 (China); Liu Shaobin [College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); State Key Laboratory of Millimeter Waves of Southeast University, Nanjing Jiangsu 210096 (China); Kong Xiangkun, Chenchen; Bian Borui [College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China)

2013-04-15T23:59:59.000Z

Note: This page contains sample records for the topic "band-gap semiconductor oxide" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Wide-band-gap solar cells with high stabilized performance. Annual subcontract report, July 15, 1994--July 14, 1995  

SciTech Connect (OSTI)

This report describes work performed by Pennsylvania State University in collaboration with the NREL Wide-Band-Gap Team. The goal of this team is to develop a single-junction, wide-gap solar cell with good stabilized parameters. The objectives of the subcontract are to (1) develop a cost-effective amorphous silicon PV technology to foster a viable amorphous silicon PV industry in the US, ensuring that this industry remains a world leader in the a-Si technology; (2) help the US a-Si PV industry achieve the US DOE PV Program FY 1995 milestone of 10% stable efficiency commercial thin-film modules; (3) help the US a-Si PV industry achieve 12% stable efficiency multi-junction a-Si:H modules for large-scale utility use by the year 2005. Issues covered in this report include (1) improved understanding of stability in materials and solar cells, (2) intrinsic materials optimization, (3) solar cells optimized for intrinsic layer performance, (4) p-type layer optimization, (5) top cell interfaces, and (6) solar cell grading.

Wronski, C.R.; Collins, R.W.; Fonash, S.J. [Pennsylvania State Univ., University Park, PA (United States)

1995-11-01T23:59:59.000Z

102

ESS 2012 Peer Review - Engineered Gate Oxides for Wide Bandgap Semiconductor MOSFETs - Jon Ihlefeld, SNL  

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

-5 -5 10 -4 10 -3 10 -2 10 -1 10 0 10 1 -6 -4 -2 0 2 4 6 8 10 |J Leakage | (A-cm -2 ) Semiconductor Voltage (V) Engineered Gate Oxides for Wide Bandgap S emiconductor M OSFETs* Jon I hlefeld, M ichael B rumbach, S andeepan D asGupta, and Stanley AtciEy Sandia NaGonal Laboratories *Sponsored b y t he U .S. D epartment o f E nergy's O ffice o f E lectricity E nergy S torage Systems P rogram jihlefe@sandia.gov, 505---844---3162; s atciE@sandia.gov, 505---284---2701 Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. SAND No. 2011-XXXXP Cooling Power electronics Energy storage Energy storage -V gate Low defect oxide Metal gate Wide

103

Long-term research in Japan: amorphous metals, metal oxide varistors, high-power semiconductors and superconducting generators  

SciTech Connect (OSTI)

The review revealed that significant activity is under way in the research of amorphous metals, but that little fundamental work is being pursued on metal oxide varistors and high-power semiconductors. Also, the investigation of long-term research program plans for superconducting generators reveals that activity is at a low level, pending the recommendations of a study currently being conducted through Japan's Central Electric Power Council.

Hane, G.J.; Yorozu, M.; Sogabe, T.; Suzuki, S.

1985-04-01T23:59:59.000Z

104

Ultra-high vacuum fabrication and electrical characterization of environmentally sensitive metal oxide semiconductor capacitors  

SciTech Connect (OSTI)

We describe an integrated, ultra-high vacuum system for metal oxide semiconductor (MOS) device fabrication and characterization. Such a system is advantageous for electrical property measurements of electronic devices consisting of environmentally sensitive materials especially as device dimensions approach the nanoscale. Without exposure to atomosphere, MOS capacitors were fabricated by evaporating gate metal on molecular-beam-epitaxy (MBE) grown dielectrics on 3 inch-diameter substrates through a shadow mask in a UHV electrode-patterning chamber. The finished device is transferred in vacuum to an in-situ, UHV electrical characterization probe station that was designed with standard UHV coaxial feedthroughs and UHV-compatible, Kapton-insulated coaxial cable. The probe station also includes a heated sample stage that allows for annealing and measurements in a controlled ambient. We obtained excellent agreement between air-ambient ex-situ and in-situ probe station measurements utilizing a capacitor standard compatible with UHV based on single crystal sapphire as the dielectric. The measurements show less than 0.3 % dispersion for frequencies from 20 Hz to 1 MHz. We have successfully measured MOS capacitors and are sensitive to a density of interface states of 1x1010 states cm-2 eV-1. These measurements also show 0.5 % dispersion for measurement frequencies from 20 Hz to 1 kHz and less than 0.1 % from 1 kHz to 1 MHz. The integrated system presented here is one where complex, MBE-grown MOS heterostructures can be synthesized and tested rapidly to elucidate new field-effect-device physics and functionality.

Billman, Curt [Oak Ridge National Laboratory (ORNL); Walker, Frederick Joseph [ORNL

2007-01-01T23:59:59.000Z

105

Fabry-Perot tuning of the band-gap polarity in plasmonic crystals Jin E. Kihm,1 Y. C. Yoon,1 D. J. Park,1 Y. H. Ahn,1 C. Ropers,2 C. Lienau,2,3 J. Kim,4 Q. H. Park,5 and D. S. Kim1,  

E-Print Network [OSTI]

-resolved transmission spectra of nanoslit arrays in metal films demonstrate band-gap formation resulting from surface-gap flipping. Our results indicate an interesting route towards band-gap engineering in plasmonic crystals. DOI of electronic and photonic band gaps--i.e., energy regions with a vanishing density of states in crystal- line

Peinke, Joachim

106

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

E-Print Network [OSTI]

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 ...

Pereira, LMC; Wahl, U

107

Multichannel, time-resolved picosecond laser ultrasound imaging and spectroscopy with custom complementary metal-oxide-semiconductor detector  

SciTech Connect (OSTI)

This paper presents a multichannel, time-resolved picosecond laser ultrasound system that uses a custom complementary metal-oxide-semiconductor linear array detector. This novel sensor allows parallel phase-sensitive detection of very low contrast modulated signals with performance in each channel comparable to that of a discrete photodiode and a lock-in amplifier. Application of the instrument is demonstrated by parallelizing spatial measurements to produce two-dimensional thickness maps on a layered sample, and spectroscopic parallelization is demonstrated by presenting the measured Brillouin oscillations from a gallium arsenide wafer. This paper demonstrates the significant advantages of our approach to pump probe systems, especially picosecond ultrasonics.

Smith, Richard J.; Light, Roger A.; Johnston, Nicholas S.; Pitter, Mark C.; Somekh, Mike G. [Institute of Biophysics, Imaging and Optical Science, University of Nottingham, Nottinghamshire NG7 2RD (United Kingdom); Sharples, Steve D. [Applied Optics Group, Electrical Systems and Optics Research Division, University of Nottingham, Nottinghamshire NG7 2RD (United Kingdom)

2010-02-15T23:59:59.000Z

108

Low-band-gap, amorphous-silicon-based alloys by photochemical vapor deposition: Final report, 1 October 1985--30 November 1986  

SciTech Connect (OSTI)

Thin films of hydrogenated amorphous silicon-germanium alloys were deposited by mercury-sensitized photochemical vapor deposition using a novel photo-CVD reactor. Thin films of a-Si/sub 1-x/Ge/sub x/:H with 0 less than or equal to x less than or equal to 1 and 1.0 less than E/sub g/ less than 1.8 eV were deposited from mixtures of silane and disilane with germane and inert gas diluents at substrate temperatures from 160/degree/ to 200/degree/C. Alloy films were characterized by measurements of photo- and dark conductivity, electron mobility-lifetime product, sub-band-gap absorption, and density of states. Dilution with hydrogen increased the photoconductivity to 10/sup /minus/5/ Scm and mobility-lifetime product to 6 /times/ 10/sup /minus/8/ cm/sup 2/V for alloys having a band gap of 1.4 eV.

Baron, B.N.; Hegedus, S.S.; Jackson, S.C.

1988-02-01T23:59:59.000Z

109

Low-band-gap, amorphous-silicon-based alloys by chemical vapor deposition: Annual subcontract report, 1 October 1985-31 January 1986  

SciTech Connect (OSTI)

This research was conducted to determine the potential of photochemical vapor deposition (photo-CVD) for producing high-quality, low-band-gap amorphous silicon germanium alloys for use in high-efficiency, multijunction, thin-film photovoltaic solar cells. A photo-CVD reactor for mercury-sensitized photolysis of silane-germane and disilane-germane mixtures was developed. Alloy thin films of undoped a-Si/sub 1-x/Ge/sub x/:H were deposited using mercury vapor mixed with SiH/sub 4/ or Si/sub 2/H/sub 6/, GeH/sub 4/, and diluent gas of Ar, He, or H/sub 2/. Materials properties were characterized by measurements of Ge content, optical transmission and reflection, and dark and photo-conductivity. Opto-electronic properties of photo-CVD a-Si/sub 1-x/Ge/sub x/:H were found to be comparable to glow discharge and sputtered materials. Moreover, p-i-n solar cells with low-band-gap i-layers were able to be fabricated by photo-CVD.

Baron, B.N.; Jackson, S.C.

1986-12-01T23:59:59.000Z

110

Theory of non-Markovian decay of a cascade atom in high-Q cavities and photonic band-gap materials  

E-Print Network [OSTI]

The dynamics of a three-level atom in a cascade configuration with both transitions coupled to a single structured reservoir of quantized field modes is treated using Laplace transform methods applied to the coupled amplitude equations. Results are also obtained from master equations by two different approaches, that is, involving either pseudomodes or quasimodes. Two different types of reservoir are considered, namely a high-Q cavity and a photonic band-gap system, in which the respective reservoir structure functions involve Lorentzians. Non-resonant transitions are included in the model. In all cases non-Markovian behaviour for the atomic system can be found, such as oscillatory decay for the high-Q cavity case and population trapping for the photonic band-gap case. In the master equation approaches, the atomic system is augmented by a small number of pseudomodes or quasimodes, which in the quasimode approach themselves undergo Markovian relaxation into a flat reservoir of continuum quasimodes. Results from these methods are found to be identical to those from the Laplace transform method including two-photon excitation of the reservoir with both emitting sequences. This shows that complicated non-Markovian decays of an atomic system into structured EM field reservoirs can be described by Markovian models for the atomic system coupled to a small number of pseudomodes or quasimodes.

B. M. Garraway; B. J. Dalton

2006-02-13T23:59:59.000Z

111

Investigation on edge fringing effect and oxide thickness dependence of inversion current in metal-oxide-semiconductor tunneling diodes with comb-shaped electrodes  

SciTech Connect (OSTI)

A particular edge-dependent inversion current behavior of metal-oxide-semiconductor (MOS) tunneling diodes was investigated utilizing square and comb-shaped electrodes. The inversion tunneling current exhibits the strong dependence on the tooth size of comb-shaped electrodes and oxide thickness. Detailed illustrations of current conduction mechanism are developed by simulation and experimental measurement results. It is found that the electron diffusion current and Schottky barrier height lowering for hole tunneling current both contribute on inversion current conduction. In MOS tunneling photodiode applications, the photoresponse can be improved by decreasing SiO{sub 2} thickness and using comb-shaped electrodes with smaller tooth spacing. Meantime, the high and steady photosensitivity can also be approached by introducing HfO{sub 2} into dielectric stacks.

Lin, Chien-Chih; Hsu, Pei-Lun; Lin, Li; Hwu, Jenn-Gwo, E-mail: jghwu@ntu.edu.tw [Graduate Institute of Electronics Engineering, Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan (China)

2014-03-28T23:59:59.000Z

112

PHYSICAL REVIEW B 84, 245206 (2011) First-principles study of band gap engineering via oxygen vacancy doping  

E-Print Network [OSTI]

formulate guidelines that can be used to predict the location of oxygen vacancies in perovskite solid transport of O2- ions through the oxide electrolyte membrane over a range of temperatures. In solar energy several chemical compositions and different cation arrangements for the two Zr-modified solid solutions

Rappe, Andrew M.

113

Electronic properties and reliability of the silicon dioxide / silicon carbide interface.  

E-Print Network [OSTI]

??Silicon carbide has been preferred over other wide band-gap semiconductors for high power applications because of its unique ability to grow a thermal oxide, challenges… (more)

Rozen, John

2008-01-01T23:59:59.000Z

114

Band gap tuning and optical absorption in type-II InAs/GaSb mid infrared short period superlattices: 14 bands K Dot-Operator p study  

SciTech Connect (OSTI)

The MBE growth of short-period InAs/GaSb type-II superlattice structures, varied around 20.5 A InAs/24 A GaSb were [J. Applied physics, 96, 2580 (2004)] carried out by Haugan et al. These SLs were designed to produce devices with an optimum mid-infrared photoresponse and a sharpest photoresponse cutoff. We have used a realistic and reliable 14-band k.p formalism description of the superlattice electronic band structure to calculate the absorption coefficient in such short-period InAs/GaSb type-II superlattices. The parameters for this formalism are known from fitting to independent experiments for the bulk materials. The band-gap energies are obtained without any fitting parameters, and are in good agreement with experimental data.

AbuEl-Rub, Khaled M. [Department of Applied Physical Sciences, Jordan University of Science and Technology Irbid, 21141 (Jordan)

2012-09-06T23:59:59.000Z

115

Band gap engineering of In{sub 2}O{sub 3} by alloying with Tl{sub 2}O{sub 3}  

SciTech Connect (OSTI)

Efficient modulation of the bandgap of In{sub 2}O{sub 3} will open up a route to improved electronic properties. We demonstrate using ab initio calculations that Tl incorporation into In{sub 2}O{sub 3} reduces the band gap and confirm that narrowing of the gap is observed by X-ray photoemission spectroscopy on ceramic surfaces. Incorporation of Tl does not break the symmetry of the allowed optical transitions, meaning that the doped thin films should retain optical transparency in the visible region, in combination with a lowering of the conduction band effective mass. We propose that Tl-doping may be an efficient way to increase the dopability and carrier mobility of In{sub 2}O{sub 3}.

Scanlon, David O., E-mail: d.scanlon@ucl.ac.uk [Kathleen Lonsdale Materials Chemistry, Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ (United Kingdom); Diamond Light Source Ltd., Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE (United Kingdom); Regoutz, Anna; Egdell, Russell G. [Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QR (United Kingdom)] [Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QR (United Kingdom); Morgan, David J. [Cardiff Catalysis Institute (CCI), School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT (United Kingdom)] [Cardiff Catalysis Institute (CCI), School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT (United Kingdom); Watson, Graeme W. [School of Chemistry and CRANN, Trinity College Dublin, Dublin 2 (Ireland)] [School of Chemistry and CRANN, Trinity College Dublin, Dublin 2 (Ireland)

2013-12-23T23:59:59.000Z

116

Oxide-based method of making compound semiconductor films and making related electronic devices  

DOE Patents [OSTI]

A method for forming a compound film includes the steps of preparing a source material, depositing the source material on a base and forming a preparatory film from the source material, heating the preparatory film in a suitable atmosphere to form a precursor film, and providing suitable material to said precursor film to form the compound film. The source material includes oxide-containing particles including Group IB and IIIA elements. The precursor film includes non-oxide Group IB and IIIA elements. The compound film includes a Group IB-IIIA-VIA compound. The oxides may constitute greater than about 95 molar percent of the Group IB elements and greater than about 95 molar percent of the Group IIIA elements in the source material. Similarly, non-oxides may constitute greater than about 95 molar percent of the Group IB elements and greater than about 95 molar percent of the Group IIIA elements in the precursor film. The molar ratio of Group IB to Group IIIA elements in the source material may be greater than about 0.6 and less than about 1.0, or substantially greater that 1.0, in which case this ratio in the compound film may be reduced to greater than about 0.6 and less than about 1.0. The source material may be prepared as an ink from particles in powder form. The oxide-containing particles may include a dopant, as may the compound film. Compound films including a Group IIB-IVA-VA compound may be substituted using appropriate substitutions in the method. The method, also, is applicable to fabrication of solar cells and other electronic devices.

Kapur, Vijay K. (Tarzana, CA); Basol, Bulent M. (Manhattan Beach, CA); Leidholm, Craig R. (Woodland Hills, CA); Roe, Robert A. (Glendale, CA)

2000-01-01T23:59:59.000Z

117

Band gap of CdTe and Cd{sub 0.9}Zn{sub 0.1}Te crystals  

SciTech Connect (OSTI)

The band gap E{sub g} of the CdTe and Cd{sub 0.9}Zn{sub 0.1}Te crystals and its temperature dependence are determined by optical methods. This is motivated by considerable contradictoriness of the published data, which hampers the interpretation and calculation of characteristics of detectors of X-ray and {gamma} radiation based on these materials (E{sub g} = 1.39-1.54 and 1.51-1.6 eV for CdTe and Cd{sub 0.9}Zn{sub 0.1}Te, respectively). The used procedure of determination of E{sub g} is analyzed from the viewpoint of the influence of the factors leading to inaccuracies in determination of its value. The measurements are performed for well-purified high-quality samples. The acquired data for CdTe (E{sub g} = 1.47-1.48 eV) and Cd{sub 0.9}Zn{sub 0.1}Te (E{sub g} = 1.52-1.53 eV) at room temperature substantially narrow the range of accurate determination of E{sub g}.

Kosyachenko, L. A., E-mail: lakos@chv.ukrpact.net; Sklyarchuk, V. M.; Sklyarchuk, O. V.; Maslyanchuk, O. L. [Chernovtsy National University (Ukraine)

2011-10-15T23:59:59.000Z

118

Performance characterization of microtomography with complementary metal-oxide-semiconductor detectors for computer-aided defect inspection  

SciTech Connect (OSTI)

We developed a computer-aided defect inspection system based on computed tomography (CT). The system consists of a homemade small cone-beam CT (CBCT) system and a graphical toolbox, which is used to extract a computer-aided design (CAD) model from the CT data. In the small CBCT system, the x-ray imaging detector is based on a complementary metal-oxide-semiconductor photodiode array in conjunction with a scintillator. Imaging performance of the detector was evaluated in terms of modulation-transfer function, noise-power spectrum, and detective quantum efficiency. The tomographic imaging performance of the small CBCT system was evaluated in terms of signal-to-noise ratio and contrast-to-noise ratio. The graphical toolbox to support defect inspection incorporates various functional tools such as volume rendering, segmentation, triangular-mesh data generation, and data reduction. All the tools have been integrated in a graphical-user interface form. The developed system can provide rapid visual inspection as well as quantitative evaluation of defects by comparing the extracted CAD file with the original file, if available, of an object. The performance of the developed system is demonstrated with experimental CT volume data.

Kim, Ho Kyung; Yun, Seungman; Han, Jong Chul; Youn, Hanbean; Cho, Min Kook; Lim, Chang Hwy [School of Mechanical Engineering, Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735 (Korea, Republic of); Heo, Sung Kyn; Shon, Cheol-Soon [Sensor Business Division, E-WOO Technology Co., Ltd., Bora-dong, Giheung, Gyeonggi-do 449-904 (Korea, Republic of); Kim, Seong-Sik; Cho, Bong Hae [School of Dentistry, Pusan National University, Ami-dong, Seo-gu, Busan 602-739 (Korea, Republic of); Achterkirchen, Thorsten Graeve [Rad-icon Imaging Corp., Belick Street, Santa Clara, CA 95054-2404 (United States)

2009-05-01T23:59:59.000Z

119

Selective CO{sub 2} reduction conjugated with H{sub 2}O oxidation utilizing semiconductor/metal-complex hybrid photocatalysts  

SciTech Connect (OSTI)

We developed a new hybrid photocatalyst for CO{sub 2} reduction, which is composed of a semiconductor and a metal complex. In the hybrid photocatalyst, ?G between the position of conduction band minimum (E{sub CBM}) of the semiconductor and the CO{sub 2} reduction potential of the complex is an essential factor for realizing fast electron transfer from the conduction band of semiconductor to metal complex leading to high photocatalytic activity. On the basis of this concept, the hybrid photocatalyst InP/Ru-complex, which functions in aqueous media, was developed. The photoreduction of CO{sub 2} to formate using water as an electron donor and a proton source was successfully achieved as a Z-scheme system by functionally conjugating the InP/Ru-complex photocatalyst for CO{sub 2} reduction with a TiO{sub 2} photocatalyst for water oxidation. The conversion efficiency from solar energy to chemical energy was ca. 0.04%, which approaches that for photosynthesis in a plant. Because this system can be applied to many other inorganic semiconductors and metal-complex catalysts, the efficiency and reaction selectivity can be enhanced by optimization of the electron transfer process including the energy-band configurations, conjugation conformations, and catalyst structures. This electrical-bias-free reaction is a huge leap forward for future practical applications of artificial photosynthesis under solar irradiation to produce organic species.

Morikawa, T., E-mail: morikawa@mosk.tytlabs.co.jp; Sato, S., E-mail: morikawa@mosk.tytlabs.co.jp; Arai, T., E-mail: morikawa@mosk.tytlabs.co.jp; Uemura, K., E-mail: morikawa@mosk.tytlabs.co.jp; Yamanaka, K. I., E-mail: morikawa@mosk.tytlabs.co.jp; Suzuki, T. M., E-mail: morikawa@mosk.tytlabs.co.jp; Kajino, T., E-mail: morikawa@mosk.tytlabs.co.jp; Motohiro, T., E-mail: morikawa@mosk.tytlabs.co.jp [Toyota Central R and D Labs, Inc., Nagakute, Aichi 480-1192 (Japan)

2013-12-10T23:59:59.000Z

120

Performance analysis of boron nitride embedded armchair graphene nanoribbon metal–oxide–semiconductor field effect transistor with Stone Wales defects  

SciTech Connect (OSTI)

We study the performance of a hybrid Graphene-Boron Nitride armchair nanoribbon (a-GNR-BN) n-MOSFET at its ballistic transport limit. We consider three geometric configurations 3p, 3p + 1, and 3p + 2 of a-GNR-BN with BN atoms embedded on either side (2, 4, and 6 BN) on the GNR. Material properties like band gap, effective mass, and density of states of these H-passivated structures are evaluated using the Density Functional Theory. Using these material parameters, self-consistent Poisson-Schrodinger simulations are carried out under the Non Equilibrium Green's Function formalism to calculate the ballistic n-MOSFET device characteristics. For a hybrid nanoribbon of width ?5?nm, the simulated ON current is found to be in the range of 265??A–280??A with an ON/OFF ratio 7.1 × 10{sup 6}–7.4 × 10{sup 6} for a V{sub DD}?=?0.68?V corresponding to 10?nm technology node. We further study the impact of randomly distributed Stone Wales (SW) defects in these hybrid structures and only 2.5% degradation of ON current is observed for SW defect density of 3.18%.

Chanana, Anuja; Sengupta, Amretashis; Mahapatra, Santanu [Nano Scale Device Research Laboratory, Department of Electronic Systems Engineering, Indian Institute of Science, Bangalore 560 012 (India)

2014-01-21T23:59:59.000Z

Note: This page contains sample records for the topic "band-gap semiconductor oxide" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Semiconductor assisted metal deposition for nanolithography applications  

DOE Patents [OSTI]

An article of manufacture and method of forming nanoparticle sized material components. A semiconductor oxide substrate includes nanoparticles of semiconductor oxide. A modifier is deposited onto the nanoparticles, and a source of metal ions are deposited in association with the semiconductor and the modifier, the modifier enabling electronic hole scavenging and chelation of the metal ions. The metal ions and modifier are illuminated to cause reduction of the metal ions to metal onto the semiconductor nanoparticles.

Rajh, Tijana (Naperville, IL); Meshkov, Natalia (Downers Grove, IL); Nedelijkovic, Jovan M. (Belgrade, YU); Skubal, Laura R. (West Brooklyn, IL); Tiede, David M. (Elmhurst, IL); Thurnauer, Marion (Downers Grove, IL)

2001-01-01T23:59:59.000Z

122

Semiconductor assisted metal deposition for nanolithography applications  

DOE Patents [OSTI]

An article of manufacture and method of forming nanoparticle sized material components. A semiconductor oxide substrate includes nanoparticles of semiconductor oxide. A modifier is deposited onto the nanoparticles, and a source of metal ions are deposited in association with the semiconductor and the modifier, the modifier enabling electronic hole scavenging and chelation of the metal ions. The metal ions and modifier are illuminated to cause reduction of the metal ions to metal onto the semiconductor nanoparticles.

Rajh, Tijana (Naperville, IL); Meshkov, Natalia (Downers Grove, IL); Nedelijkovic, Jovan M. (Belgrade, YU); Skubal, Laura R. (West Brooklyn, IL); Tiede, David M. (Elmhurst, IL); Thurnauer, Marion (Downers Grove, IL)

2002-01-01T23:59:59.000Z

123

Novel, band-controlled metal oxide compositions for semiconductor-mediated photocatalytic splitting of water to produce H{sub 2}  

SciTech Connect (OSTI)

Semiconductor-mediated photo-catalytic dissociation of water offers a unique opportunity for the production of H{sub 2}, a sustainable source of energy. More efficient and chemically stable photo-catalysts, however, remain a vital requirement for commercial viability of this process. The recent research in my group has focused on the synthesis of several new metal oxide (MO) photo-catalysts, such as: LaInO{sub 3}, GaFeO{sub 3}, InVO{sub 4}, In{sub 2}TiO{sub 5} and nanotubular TiO{sub 2}. These samples of controlled grain morphology have been synthesized by using different synthesis protocols and with and without coating of a noble metal co-catalyst. The doping of an impurity, either at cationic or at anionic lattice site, has helped in the tailoring of band structure and making these oxides visible-light-sensitive. Our study has revealed that the surface characteristics, grain morphology, band structure, and doping-induced lattice imperfections control the photo-physical properties and overall photo-catalytic water splitting activity of these metal/MO composites [1-6]. We have demonstrated that, besides promoting certain charge-transfer steps, metal-semiconductor interfaces influence the adsorption of water molecules and their subsequent interaction with photo-generated electron-hole pair at the catalyst surface. The role played by the above-mentioned micro-structural properties in photo-catalytic water splitting process will be discussed.

Gupta, Narendra M. [Catalysis Division, National Chemical Laboratory, Dr. Homi Bhabha Road, Pune - 411008 (India)

2013-02-05T23:59:59.000Z

124

Independent and correlated composition behavior of material properties:?Application to energy band gaps for the Ga?In1-?P?As1-? and Ga?In1-?P?Sb?As1-?-? alloys  

Science Journals Connector (OSTI)

A correlated function expansion (CFE) is introduced (a) to identify the role of independent and correlated composition variations upon a desired material property, and (b) to provide an efficient means to compute the property throughout the composition space. As an example the contributions of independent and correlated composition behavior upon the principal energy band gaps for the alloys Ga?In1-?P?As1-? and Ga?In1-?P?Sb?As1-?-? are calculated and analyzed by applying the CFE to the universal tight-binding (UTB) Hamiltonian model of the alloys. The convergence properties of the CFE over the entire composition variable space (?,?,?) are examined upon including independent, pair-, and triple-correlated terms. By retaining only independent component contributions in the CFE it was possible to represent the UTB results to better than 90% accuracy for both the alloys Ga?In1-?P?As1-? and Ga?In1-?P?Sb?As1-?-?. Pair composition correlations contributed approximately 5–10 % to the band gaps in both alloys and for Ga?In1-?P?Sb?As1-?-? the triple correlations were at the level of ?3%. The CFE is a generic tool capable of simplifying efforts at finding desired alloy compositions for material properties.

Kyurhee Shim and Herschel Rabitz

1998-07-15T23:59:59.000Z

125

Predicted band structures of III-V semiconductors in the wurtzite phase  

SciTech Connect (OSTI)

While non-nitride III-V semiconductors typically have a zinc-blende structure, they may also form wurtzite crystals under pressure or when grown as nanowhiskers. This makes electronic structure calculation difficult since the band structures of wurtzite III-V semiconductors are poorly characterized. We have calculated the electronic band structure for nine III-V semiconductors in the wurtzite phase using transferable empirical pseudopotentials including spin-orbit coupling. We find that all the materials have direct gaps. Our results differ significantly from earlier ab initio calculations, and where experimental results are available (InP, InAs, and GaAs) our calculated band gaps are in good agreement. We tabulate energies, effective masses, and linear and cubic Dresselhaus zero-field spin-splitting coefficients for the zone-center states. The large zero-field spin-splitting coefficients we find may facilitate the development of spin-based devices.

De, A.; Pryor, Craig E. [Department of Physics and Astronomy and Optical Science and Technology Center, University of Iowa, Iowa City, Iowa 52242 (United States)

2010-04-15T23:59:59.000Z

126

Lattice mismatched compound semiconductors and devices on silicon  

E-Print Network [OSTI]

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 ...

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

2011-01-01T23:59:59.000Z

127

IEEE TRANSACTIONS ON NANOTECHNOLOGY, VOL. 10, NO. 3, MAY 2011 499 TiSi2 Nanocrystal Metal Oxide Semiconductor Field  

E-Print Network [OSTI]

IEEE TRANSACTIONS ON NANOTECHNOLOGY, VOL. 10, NO. 3, MAY 2011 499 TiSi2 Nanocrystal Metal Oxide memory window, faster writing and erasing, and longer retention lifetime as a result of the metallic property of the silicide NCs. Due to thermally stable, CMOS compatible properties, TiSi2 NCs are highly

Yang, Zheng

128

Trend of tunnel magnetoresistance and variation in threshold voltage for keeping data load robustness of metal–oxide–semiconductor/magnetic tunnel junction hybrid latches  

Science Journals Connector (OSTI)

The robustness of data load of metal–oxide–semiconductor/magnetic tunnel junction (MOS/MTJ) hybrid latches at power-on is examined by using Monte Carlo simulation with the variations in magnetoresistances for MTJs and in threshold voltages for MOSFETs involved in 90?nm technology node. Three differential pair type spin-transfer-torque-magnetic random access memory cells (4T2MTJ 6T2MTJ and 8T2MTJ) are compared for their successful data load at power-on. It is found that the 4T2MTJ cell has the largest pass area in the shmoo plot in TMR ratio (tunnel magnetoresistance ratio) and Vdd in which a whole 256?kb cell array can be powered-on successfully. The minimum TMR ratio for the 4T2MTJ in 0.9?V?

S. Ikeda; T. Hanyu; H. Ohno

2014-01-01T23:59:59.000Z

129

Variable temperature semiconductor film deposition  

DOE Patents [OSTI]

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.

Li, X.; Sheldon, P.

1998-01-27T23:59:59.000Z

130

Calculation of the electron structure of vacancies and their compensated states in III-VI semiconductors  

SciTech Connect (OSTI)

The Green's functions theory and the bond-orbital model are used as a basis for calculations of the electron structure of local defects-specifically, vacancies and their compensated states in III-VI semiconductors. The energy levels in the band gap are established, and the changes induced in the electron densities in the GaS, GaSe, and InSe semiconductors by anion and cation vacancies and their compensated states are calculated. It is established that, if a vacancy is compensated by an atom of an element from the same subgroup with the same tetrahedral coordination and if the ionic radius of the compensating atom is smaller than that of the substituted atom, the local levels formed by the vacancy completely disappear. It is shown that this mechanism of compensation of vacancies provides a means not only for recovering the parameters of the crystal, but for improving the characteristics of the crystal as well.

Mehrabova, M. A., E-mail: Mehrabova@mail.ru; Madatov, R. S. [Azerbaijan National Academy of Sciences, Institute of Radiation Problems (Azerbaijan)

2011-08-15T23:59:59.000Z

131

Quantitative determination of local potential values in inhomogeneously doped semiconductors by scanning tunneling microscopy  

Science Journals Connector (OSTI)

Local potential changes arising from nanoscale three-dimensional spatial fluctuations in the dopant distribution in Zn-doped GaAs were investigated quantitatively by scanning tunneling microscopy and spectroscopy at (110) cleavage surfaces. Tunneling spectra measured in areas with different local doping concentration show apparent shifts of the valence band edge and apparent changes of the band gap. A quantitative analysis, combined with band bending and tunnel current simulations, demonstrates that these effects arise from tip-induced band bending that modulates the real potential changes. It is illustrated how exact potential changes between locally high and low doped areas can be determined. It is found that the local potential fluctuations in three-dimensionally doped semiconductors are approximately one order of magnitude smaller that those observed in two-dimensionally doped semiconductors.

P. H. Weidlich, R. E. Dunin-Borkowski, and Ph. Ebert

2011-08-29T23:59:59.000Z

132

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

SciTech Connect (OSTI)

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.

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

133

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

SciTech Connect (OSTI)

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.

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

134

Entanglement Sudden Death in Band Gaps  

E-Print Network [OSTI]

Using the pseudomode method, we evaluate exactly time-dependent entanglement for two independent qubits, each coupled to a non-Markovian structured environment. Our results suggest a possible way to control entanglement sudden death by modifying the qubit-pseudomode detuning and the spectrum of the reservoirs. Particularly, in environments structured by a model of a density-of-states gap which has two poles, entanglement trapping and prevention of entanglement sudden death occur in the weak-coupling regime.

Ying-Jie Zhang

2009-11-10T23:59:59.000Z

135

Photo-Degradation of Methelyne Blue over V2O5–TiO2 Nano-Porous Layers Synthesized by Micro Arc Oxidation  

Science Journals Connector (OSTI)

V2O5–TiO2 porous layers were synthesized via micro-arc oxidation for the first time. The effect of...k = 0.0228 min?1. The band gap energies of the vanadia–titania and pure titania layers were calculated as 2.56 ...

M. R. Bayati; F. Golestani-Fard; A. Z. Moshfegh

2010-01-01T23:59:59.000Z

136

ADVERTISEMENT SEMICONDUCTORS  

E-Print Network [OSTI]

ADVERTISEMENT SEMICONDUCTORS: 07.14.2010 Nano-enabled Coating Makes Aircraft Invisible Humble paint... The oil-separating centrifuges will work, but they... MORE FROM IEEE SPECTRUM ROBOTICS: 06.16.2010 Robo.01.2006 Look Out, Beckham: Here Come the Robots At the "World Cup" for robots, the talk is that one day

Stryk, Oskar von

137

L-asparagine crystals with wide gap semiconductor features: Optical absorption measurements and density functional theory computations  

SciTech Connect (OSTI)

Results of optical absorption measurements are presented together with calculated structural, electronic, and optical properties for the anhydrous monoclinic L-asparagine crystal. Density functional theory (DFT) within the generalized gradient approximation (GGA) including dispersion effects (TS, Grimme) was employed to perform the calculations. The optical absorption measurements revealed that the anhydrous monoclinic L-asparagine crystal is a wide band gap material with 4.95 eV main gap energy. DFT-GGA+TS simulations, on the other hand, produced structural parameters in very good agreement with X-ray data. The lattice parameter differences ?a, ?b, ?c between theory and experiment were as small as 0.020, 0.051, and 0.022 Å, respectively. The calculated band gap energy is smaller than the experimental data by about 15%, with a 4.23 eV indirect band gap corresponding to Z???? and Z???? transitions. Three other indirect band gaps of 4.30 eV, 4.32 eV, and 4.36 eV are assigned to ?3 ???, ?1 ???, and ?2 ??? transitions, respectively. ?-sol computations, on the other hand, predict a main band gap of 5.00 eV, just 50 meV above the experimental value. Electronic wavefunctions mainly originating from O 2p–carboxyl, C 2p–side chain, and C 2p–carboxyl orbitals contribute most significantly to the highest valence and lowest conduction energy bands, respectively. By varying the lattice parameters from their converged equilibrium values, we show that the unit cell is less stiff along the b direction than for the a and c directions. Effective mass calculations suggest that hole transport behavior is more anisotropic than electron transport, but the mass values allow for some charge mobility except along a direction perpendicular to the molecular layers of L-asparagine which form the crystal, so anhydrous monoclinic L-asparagine crystals could behave as wide gap semiconductors. Finally, the calculations point to a high degree of optical anisotropy for the absorption and complex dielectric function, with more structured curves for incident light polarized along the 100 and 101 directions.

Zanatta, G.; Gottfried, C. [Departamento de Bioquímica, Universidade Federal do Rio Grande do Sul, 90035-003 Porto Alegre-RS (Brazil)] [Departamento de Bioquímica, Universidade Federal do Rio Grande do Sul, 90035-003 Porto Alegre-RS (Brazil); Silva, A. M. [Universidade Estadual do Piauí, 64260-000 Piripiri-Pi (Brazil)] [Universidade Estadual do Piauí, 64260-000 Piripiri-Pi (Brazil); Caetano, E. W. S., E-mail: ewcaetano@gmail.com [Instituto de Educação, Ciência e Tecnologia do Ceará, 60040-531 Fortaleza-CE (Brazil)] [Instituto de Educação, Ciência e Tecnologia do Ceará, 60040-531 Fortaleza-CE (Brazil); Sales, F. A. M.; Freire, V. N. [Departamento de Física, Universidade Federal do Ceará, Caixa Postal 6030, 60455-760 Fortaleza-CE (Brazil)] [Departamento de Física, Universidade Federal do Ceará, Caixa Postal 6030, 60455-760 Fortaleza-CE (Brazil)

2014-03-28T23:59:59.000Z

138

Development and Field-Scale Optimization of a Honeycomb Zeolite Rotor Concentrator/Recuperative Oxidizer for the Abatement of Volatile Organic Carbons from Semiconductor Industry  

Science Journals Connector (OSTI)

Also the developed rotor performance’s was evaluated in the field; (2) Direct Fired Thermal Oxidizer (DFTO), Recuperative Oxidizer (RO), Regenerative Thermal Oxidizer (RTO) and Regenerative Catalytic oxidizer (RCO) are the available incinerators and the RO was selected as the oxidizer in this work; (3) The overall performance of the developed rotor/oxidizer was explored in a field scale under varying conditions; (4) The energy saving strategy was fulfilled by reducing heat loss from the oxidizer and recovering heat from the exhaust gas. ... The available types of oxidizers include Direct Fired Thermal Oxidizer (DFTO), Recuperative Oxidizer (RO), Regenerative Thermal Oxidizer (RTO) and Regenerative Catalytic oxidizer (RCO). ... cost models were derived for recuperative thermal (TO) and regenerative thermal oxidizers (RTO). ...

Ji Yang; Yufeng Chen; Limei Cao; Yuling Guo; Jinping Jia

2011-11-17T23:59:59.000Z

139

Details in Semiconductors Gordon Conference, New London, NH, August 3-8, 2008  

SciTech Connect (OSTI)

Continuing its tradition of excellence, this Gordon Conference will focus on research at the forefront of the field of defects in homogeneous and structured semiconductors. The conference will have a strong emphasis on the control of defects during growth and processing, with an increases emphasis on nanostructures as compared to previous conferences. Electronic, magnetic, and optical properties of bulk, thin film, and nanoscale semiconductors will be discussed in detail. In contrast to many conferences, which tend to focus on specific semiconductors, this conference deals with defects in a broad range of bulk and nanoscale electronic materials. This approach has proved to be extremely fruitful for advancing fundamental understanding in emerging materials such as wide-band-gap semiconductors, doped nanoparticles, and organic semiconductors. Presentations of state-of-the-art theoretical methods will contribute to a fundamental understanding of atomic-scale phenomena. The program consists of about twenty invited talks, with plenty of discussion time, and a number of contributed poster sessions. Because of the large amount of discussion time, the conference provides an ideal forum for dealing with topics that are new and/or controversial.

Shengbai Zhang and Nancy Ryan Gray

2009-09-16T23:59:59.000Z

140

Electronic structure of diluted magnetic semiconductor superlattices: In-plane magnetic field effect  

Science Journals Connector (OSTI)

The electronic structure of diluted magnetic semiconductor (DMS) superlattices under an in-plane magnetic field is studied within the framework of the effective-mass theory; the strain effect is also included in the calculation. The numerical results show that an increase of the in-plane magnetic field renders the DMS superlattice from the direct band-gap system to the indirect band-gap system, and spatially separates the electron and the hole by changing the type-I band alignment to a type-II band alignment. The optical transition probability changes from type I to type II and back to type I like at large magnetic field. This phenomenon arises from the interplay among the superlattice potential profile, the external magnetic field, and the sp-d exchange interaction between the carriers and the magnetic ions. The shear strain induces a strong coupling of the light- and heavy-hole states and a transition of the hole ground states from “light”-hole to “heavy”-hole-like states.

Hai-Bin Wu, Kai Chang, and Jian-Bai Xia

2002-04-22T23:59:59.000Z

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141

Impact of SF{sub 6} plasma treatment on performance of TaN-HfO{sub 2}-InP metal-oxide-semiconductor field-effect transistor  

SciTech Connect (OSTI)

In this work, the experimental impact of SF{sub 6} plasma treatment on the performance of InP metal-oxide-semiconductor field-effect transistors is presented. S and F are incorporated into atomic layer deposited HfO{sub 2} via postgate SF{sub 6} plasma treatment. The decreased subthreshold swing, gate leakage (I{sub g}), and increased effective channel mobility ({mu}{sub eff}) indicate that better interface and bulk oxide quality have been achieved with SF{sub 6} plasma treatment due to the formation of stronger Hf-F bonds. Drive current (I{sub d}), transconductance (G{sub m}), and effective channel mobility ({mu}{sub eff}) are improved by 22.3%, 35%, and 35%, respectively, compared with those of control devices.

Wang Yanzhen; Chen Yenting; Zhao Han; Xue Fei; Zhou Fei; Lee, Jack C. [Department of Electrical and Computer Engineering, Microelectronics Research Center, University of Texas at Austin, Austin, Texas 78758 (United States)

2011-01-24T23:59:59.000Z

142

Photocatalysis Using Semiconductor Nanoclusters  

SciTech Connect (OSTI)

We report on experiments using nanosize MoS{sub 2} to photo-oxidize organic pollutants in water using visible light as the energy source. We have demonstrated that we can vary the redox potentials and absorbance characteristics of these small semiconductors by adjusting their size, and our studies of the photooxidation of organic molecules have revealed that the rate of oxidation increases with increasing bandgap (i.e. more positive valence band and more negative conduction band potentials). Because these photocatalysis reactions can be performed with the nanoclusters fully dispersed and stable in solution, liquid chromatography can be used to determine both the intermediate reaction products and the state of the nanoclusters during the reaction. We have demonstrated that the MoS{sub 2} nanoclusters remain unchanged during the photooxidation process by this technique. We also report on studies of MoS{sub 2} nanoclusters deposited on TiO{sub 2} powder.

Thurston, T.R.; Wilcoxon,J.P.

1999-01-21T23:59:59.000Z

143

Waste minimization in semiconductor processing  

SciTech Connect (OSTI)

The US semiconductor industry uses 5--7 thousand pounds of arsine annually. Fifty to eighty percent of the arsine used becomes a waste product, which requires abatement. Traditional methods of abatement are reviewed with an emphasis on dry chemical scrubbing. A variety of dry chemical scrubbing materials were evaluated for arsine capacity, using activated carbon as the baseline for comparison. Of the available technologies, dry chemical scrubbing is the most effective means of minimizing arsenic containing waste generated from semiconductor effluents. A copper oxide based media has been identified which has high capacity, high efficiency and treats the spectrum of gases used in MOCVD processes. Reclaim and recovery of spent scrubber media has the potential to drastically reduce arsenic waste from semiconductor manufacturing.

Hardwick, S.J.; Mailloux, J.C. [Novapure Corp., Danbury, CT (United States)

1994-12-31T23:59:59.000Z

144

Surface Science Letters Bulk-defect dependent adsorption on a metal oxide surface  

E-Print Network [OSTI]

-6028(01)01067-6 #12;Titanium dioxide is a wide-band gap semicon- ductor (Egap 3 eV) that can easily be reducedSurface Science Letters Bulk-defect dependent adsorption on a metal oxide surface: S/TiO2(1 1 0) E Abstract The adsorption of molecular sulfur on TiO2(1 1 0)(1 Ã? 1) has been studied with scanning tunneling

Diebold, Ulrike

145

Electronic structure of wurtzite II-VI compound semiconductor cleavage surfaces studied by scanning tunneling microscopy  

Science Journals Connector (OSTI)

We report atomically resolved scanning tunneling microscopy (STM) images of cleavage surfaces of wurtzite II-VI compound semiconductors. CdSe(112¯0), CdSe(101¯0), and CdS(101¯0) were investigated. The STM images confirm a 1×1 reconstruction for all surfaces. At negative and positive sample voltages the occupied and empty dangling-bond states above anions and cations, respectively, dominate the contrast of the STM images. No states in the band gap were found. The electronic structure of the surface permits the observation of dopant atoms in subsurface layers and thus also cross-sectional scanning tunneling microscopy studies of point defects and heterostructures.

B. Siemens, C. Domke, Ph. Ebert, and K. Urban

1997-11-15T23:59:59.000Z

146

Electrostatic screening by semiconductors  

E-Print Network [OSTI]

Electrostatic screening by semiconductors is studied, hics. applying the Thomas-Fermi theory. The semiconductor is treated as a medium with dielectric constant e due to vocalizable atoms, with force charge due to electrons. Two models...

Krcmar, Maja

2012-06-07T23:59:59.000Z

147

Spire Semiconductor formerly Bandwidth Semiconductor LLC | Open Energy  

Open Energy Info (EERE)

Semiconductor formerly Bandwidth Semiconductor LLC Semiconductor formerly Bandwidth Semiconductor LLC Jump to: navigation, search Name Spire Semiconductor (formerly Bandwidth Semiconductor LLC) Place Hudson, New Hampshire Zip 3051 Product Spire-owned US-based manufacturer of gallium-arsenide (GaAs) cells; offers design and manufacturing capabilities of concentrator cells. References Spire Semiconductor (formerly Bandwidth Semiconductor LLC)[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Spire Semiconductor (formerly Bandwidth Semiconductor LLC) is a company located in Hudson, New Hampshire . References ↑ "Spire Semiconductor (formerly Bandwidth Semiconductor LLC)" Retrieved from "http://en.openei.org/w/index.php?title=Spire_Semiconductor_formerly_Bandwidth_Semiconductor_LLC&oldid=351621"

148

Life-cycle Assessment of Semiconductors  

E-Print Network [OSTI]

The international technology roadmap for semiconductors,The international technology roadmap for semiconductors:The international technology roadmap for semiconductors,

Boyd, Sarah B.

2009-01-01T23:59:59.000Z

149

How to overcome the oxide barrier | EMSL  

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

oxide semiconductor Atomistic diagram for crystalline chromium metal (light blue) on strontium titanate(top), an equation that describes the transport process (middle), and an...

150

Block Copolymer Templated Chemistry for the Formation of Metallic Nanoparticle Arrays on Semiconductor Surfaces  

Science Journals Connector (OSTI)

One of key ingredients for many future applications is the ability to precisely pattern nanoscale features on technologically relevant semiconductor surfaces such as silicon and germanium, as well as compound semiconductors such as gallium arsenide and indium phosphide. ... Deposition of these metals is possible presumably due to the water solubility of their oxides:? Ge oxide,14c As oxide,24 and P oxide25 are soluble in water. ...

Masato Aizawa; Jillian M. Buriak

2007-09-25T23:59:59.000Z

151

Semiconductor bridge (SCB) detonator  

DOE Patents [OSTI]

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.

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

1999-01-01T23:59:59.000Z

152

Features of the band structure and conduction mechanisms in the n-HfNiSn semiconductor heavily doped with Ru  

SciTech Connect (OSTI)

The crystal and electronic structure and energy and kinetic properties of the n-HfNiSn semiconductor heavily doped with a Ru acceptor impurity are investigated in the temperature and Ru concentration ranges T = 80–400 K and N{sub A}{sup Ru} ? 9.5 × 10{sup 19}?5.7 × 10{sup 20} cm{sup ?3} (x = 0–0.03), respectively. The mechanism of structural-defect generation is established, which changes the band gap and degree of compensation of the semiconductor and consists in the simultaneous concentration reduction and elimination of donor structural defects by means of the displacement of ?1% of Ni atoms from the Hf (4a) positions, the generation of acceptor structural defects upon the substitution of Ru atoms for Ni atoms in the 4c positions, and the generation of donor defects in the form of vacancies in the Sn (4b) positions. The calculated electronic structure of HfNi{sub 1?x}Ru{sub x}Sn is consistent with the experiment. The results obtained are discussed within the Shklovsky-Efros model for a heavily doped and compensated semiconductor.

Romaka, V. A., E-mail: vromaka@polynet.lviv.ua [National Academy of Sciences of Ukraine, Pidstrygach Institute for Applied Problems in Mechanics and Mathematics (Ukraine); Rogl, P. [Universität Wien, Institut für Physikalische Chemie (Austria); Romaka, V. V. [National University Lvivska Politekhnika (Ukraine); Stadnyk, Yu. V. [Ivan Franko National University of Lviv (Ukraine); Korzh, R. O.; Krayovskyy, V. Ya. [National University Lvivska Politekhnika (Ukraine); Horyn, A. M. [Ivan Franko National University of Lviv (Ukraine)

2014-12-15T23:59:59.000Z

153

Evidence of the semiconductor-metal transition in V{sub 2}O{sub 5} thin films by the pulsed laser photoacoustic method  

SciTech Connect (OSTI)

In this work, the pulsed photoacoustic technique was used to investigate the semiconductor-metal transition of thin vanadium pentoxide films (V{sub 2}O{sub 5}) under increasing temperature. The V{sub 2}O{sub 5} thin films were simultaneously deposited by RF magnetron sputtering at room temperature, on corning glass and SnO{sub 2}:F/glass substrates, in order to compare the photoacoustic response. The elemental and structural analysis of the V{sub 2}O{sub 5} films was performed by Rutherford backscattering spectroscopy and X-ray diffraction. The optical transmission and band gap were determined using UV-Vis spectroscopy. The electrical properties were measured using four-point probe measurements with the Van der Pauw geometry.

Perez-Pacheco, A.; Acosta-Najarro, D. R.; Cruz-Manjarrez, H.; Rodriguez-Fernandez, L.; Pineda-Santamaria, J. C; Aguilar-Franco, M. [Instituto de Fisica-Universidad Nacional Autonoma de Mexico, Mexico DF (Mexico)] [Instituto de Fisica-Universidad Nacional Autonoma de Mexico, Mexico DF (Mexico); Castaneda-Guzman, R. [Laboratorio de Fotofisica y Peliculas Delgadas, CCADET-UNAM, Mexico DF (Mexico)] [Laboratorio de Fotofisica y Peliculas Delgadas, CCADET-UNAM, Mexico DF (Mexico)

2013-05-14T23:59:59.000Z

154

Invited paper History of Semiconductors  

E-Print Network [OSTI]

Abstract—The history of semiconductors is presented beginning with the first documented observation of a semiconductor effect (Faraday), through the development of the first devices (point-contact rectifiers and transistors, early field-effect transistors) and the theory of semiconductors up to the contemporary devices (SOI and multigate devices). Keywords—band theory, laser, Moore’s law, semiconductor, transistor.

Lidia ?ukasiak; Andrzej Jakubowski

155

Initiation of a passivated interface between hafnium oxide and In(Ga)As(0 0 1)-(4x2)  

SciTech Connect (OSTI)

Hafnium oxide interfaces were studied on two related group III rich semiconductor surfaces, InAs(0 0 1)-(4x2) and In{sub 0.53}Ga{sub 0.47}As(0 0 1)-(4x2), via two different methods: reactive oxidation of deposited Hf metal and electron beam deposition of HfO{sub 2}. The interfaces were investigated with scanning tunneling microscopy and spectroscopy (STS). Single Hf atom chemisorption sites were identified that are resistant to oxidation by O{sub 2}, but Hf islands are reactive to O{sub 2}. After e{sup -} beam deposition of <<1 ML of HfO{sub 2}, single chemisorption sites were identified. At low coverage (<1 ML), the n-type and p-type HfO{sub 2}/InGaAs(0 0 1)-(4x2) interfaces show p-type character in STS, which is typical of clean InGaAs(0 0 1)-(4x2). After annealing below 200 deg. C, full coverage HfO{sub 2}/InGaAs(0 0 1)-(4x2) (1-3 ML) has the surface Fermi level shifted toward the conduction band minimum for n-type InGaAs, but near the valence band maximum for p-type InGaAs. This is consistent with the HfO{sub 2}/InGaAs(0 0 1)-(4x2) interface being at least partially unpinned, i.e., a low density of states in the band gap. The partially unpinned interface results from the modest strength of the bonding between HfO{sub 2} and InGaAs(0 0 1)-(4x2) that prevents substrate atom disruption. The fortuitous structure of HfO{sub 2} on InAs(0 0 1)-(4x2) and InGaAs(0 0 1)-(4x2) allows for the elimination of the partially filled dangling bonds on the surface, which are usually responsible for Fermi level pinning.

Clemens, Jonathon B.; Bishop, Sarah R.; Kummel, Andrew C. [Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Dr., 0358, La Jolla, California 92093-0358 (United States); Lee, Joon Sung [Department of Chemistry and Biochemistry/Materials Science and Engineering Program, University of California, San Diego, 9500 Gilman Dr., 0358, La Jolla, California 92093-0358 (United States); Droopad, Ravi [Department of Physics, Texas State University-San Marcos, San Marcos, Texas 78666 (United States)

2010-06-28T23:59:59.000Z

156

INFOGRAPHIC: Wide Bandgap Semiconductors  

Office of Energy Efficiency and Renewable Energy (EERE)

Breakthrough material technology called wide bandgap (WBG) semiconductors can help reduce the amount of wasted heat, boost energy efficiency, improve reliability, reduce cost, and decrease system size in existing and future power electronics.

157

Thermal Conductivity of Polycrystalline Semiconductors and Ceramics  

E-Print Network [OSTI]

semiconductors and ceramics with desired thermalthermal conductivity of several polycrystalline semiconductors and ceramics,Thermal Conductivity of Polycrystalline Semiconductors and Ceramics

Wang, Zhaojie

2012-01-01T23:59:59.000Z

158

Low temperature production of large-grain polycrystalline semiconductors  

DOE Patents [OSTI]

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.

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

2007-04-10T23:59:59.000Z

159

Metal Oxide Semiconductors for Solar Energy Harvesting.  

E-Print Network [OSTI]

??The correlation between energy consumption and human development illustrates the importance of this societal resource. We will consume more energy in the future. In light… (more)

Thimsen, Elijah

2009-01-01T23:59:59.000Z

160

Band Gap Optimization of Two-Dimensional Photonic Crystals Using ...  

E-Print Network [OSTI]

Jul 10, 2009 ... the dielectric material and the wave vector. .... which SDP can be well applied, thanks to its efficiency and robustness of handling this type of ...... Band diagrams plotted in the figures below show the eigenvalues moving along ...

2009-07-10T23:59:59.000Z

Note: This page contains sample records for the topic "band-gap semiconductor oxide" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Experimental study of photonic band gap accelerator structures  

E-Print Network [OSTI]

This thesis reports theoretical and experimental research on a novel accelerator concept using a photonic bandgap (PBG) structure. Major advances in higher order mode (HOM) damping are required for the next generation of ...

Marsh, Roark A

2009-01-01T23:59:59.000Z

162

Multiband semiconductor compositions for photovoltaic devices  

DOE Patents [OSTI]

The highly mismatched alloy Zn.sub.1-yMn.sub.yO.sub.xTe.sub.1-x, 0.ltoreq.y<1 and 0band gap of the Zn.sub.1-yMn.sub.yTe host. With multiple band gaps that fall within the solar energy spectrum, Zn.sub.1-yMn.sub.yO.sub.xTe.sub.1-x is a material perfectly satisfying the conditions for single-junction photovoltaics with the potential for power conversion efficiencies surpassing 50%.

Walukiewicz, Wladyslaw (Kensington, CA); Yu, Kin Man (Lafayette, CA); Wu, Junqiao (Belmont, MA)

2012-03-06T23:59:59.000Z

163

Investigation of abnormal negative threshold voltage shift under positive bias stress in input/output n-channel metal-oxide-semiconductor field-effect transistors with TiN/HfO{sub 2} structure using fast I-V measurement  

SciTech Connect (OSTI)

This letter investigates abnormal negative threshold voltage shifts under positive bias stress in input/output (I/O) TiN/HfO{sub 2} n-channel metal-oxide-semiconductor field-effect transistors using fast I-V measurement. This phenomenon is attributed to a reversible charge/discharge effect in pre-existing bulk traps. Moreover, in standard performance devices, threshold-voltage (V{sub t}) shifts positively during fast I-V double sweep measurement. However, in I/O devices, V{sub t} shifts negatively since electrons escape from bulk traps to metal gate rather than channel electrons injecting to bulk traps. Consequently, decreasing pre-existing bulk traps in I/O devices, which can be achieved by adopting Hf{sub x}Zr{sub 1?x}O{sub 2} as gate oxide, can reduce the charge/discharge effect.

Ho, Szu-Han; Chen, Ching-En; Tseng, Tseung-Yuen [Department of Electronics Engineering, National Chiao Tung University, Hsinchu 300, Taiwan (China); Chang, Ting-Chang, E-mail: tcchang@mail.phys.nsysu.edu.tw; Lu, Ying-Hsin; Tsai, Jyun-Yu; Liu, Kuan-Ju [Department of Physics, National Sun Yat-Sen University, Kaohsiung 804, Taiwan (China); Cheng, Osbert; Huang, Cheng-Tung; Lu, Ching-Sen [Device Department, United Microelectronics Corporation, Tainan Science Park, Taiwan (China)

2014-03-17T23:59:59.000Z

164

Semiconductor Nanoclusters as Potential Photocatalysts  

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

0001 0001 Transport and Kinetic Processes in GaN Epitaxial Lateral Overgrowth M. E. Coltrin and C. C. Mitchell Motivation-GaN is a wide band gap semi- conductor with a broad range of potential appli- cations, e.g., high-temperature electronics, op- telectronics, chemical or biological sensors. GaN thin films usually have a high defect den- sity, leading to poor performance. Epitaxial Lat- eral Overgrowth (ELO) has been shown to greatly reduce defect densities, often by factors of 100 or more. We are conducting fundamental studies of GaN growth kinetics during ELO. Accomplishment-In ELO, a mask pattern of dielectric material is deposited on top of a GaN buffer layer. Further growth of GaN occurs se- lectively on exposed areas of the underlying buffer layer, and not on the dielectric material.

165

The roadmap for downscaling and introducing new technologies in the semiconductor industry is well laid out for the next ten years2.  

E-Print Network [OSTI]

The roadmap for downscaling and introducing new technologies in the semiconductor industry is well in the International Technology Roadmap for Semiconductors, one- dimensional structures, such as carbon nanotubes an impact on future post-complementary metal- oxide-semiconductor (CMOS) technology depends on more factors

166

Epitaxial-Graphene/Graphene-Oxide Junction: An Essential Step towards Epitaxial Graphene Electronics  

Science Journals Connector (OSTI)

Graphene-oxide (GO) flakes have been deposited to bridge the gap between two epitaxial-graphene electrodes to produce all-graphene devices. Electrical measurements indicate the presence of Schottky barriers at the graphene/graphene-oxide junctions, as a consequence of the band gap in GO. The barrier height is found to be about 0.7 eV, and is reduced after annealing at 180?°C, implying that the gap can be tuned by changing the degree of oxidation. A lower limit of the GO mobility was found to be 850??cm2/V?s, rivaling silicon. In situ local oxidation of patterned epitaxial graphene has been achieved.

Xiaosong Wu; Mike Sprinkle; Xuebin Li; Fan Ming; Claire Berger; Walt A. de Heer

2008-07-07T23:59:59.000Z

167

Kansas Advanced Semiconductor Project  

SciTech Connect (OSTI)

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.

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

168

Effect of annealing on the kinetic properties and band parameters of Hg{sub 1?x?y}Cd{sub x}Eu{sub y}Se semiconductor crystals  

SciTech Connect (OSTI)

The results of studies of the kinetic properties of Hg{sub 1?x?y}Cd{sub x}Eu{sub y}Se semiconductor crystals in the ranges of temperatures T = 77–300 K and magnetic fields H = 0.5–5 kOe before and after heat treatment of the samples in Se vapors are reported. It is established that annealing of the samples in Se vapors induces a decrease in the electron concentration. From the concentration dependence of the electron effective mass at the Fermi level, the band gap, the matrix element of interband interaction, and the electron effective mass at the bottom of the conduction band are determined.

Kovalyuk, T. T., E-mail: tarik-1006@mail.ru; Maistruk, E. V.; Maryanchuk, P. D. [Chernivtsy National University (Ukraine)

2014-12-15T23:59:59.000Z

169

Definition: Semiconductor | Open Energy Information  

Open Energy Info (EERE)

Semiconductor Semiconductor Jump to: navigation, search Dictionary.png Semiconductor Any material that has a limited capacity for conducting an electric current. Certain semiconductors, including silicon, gallium arsenide, copper indium diselenide, and cadmium telluride, are uniquely suited to the photovoltaic conversion process.[1] View on Wikipedia Wikipedia Definition A semiconductor is a material which has electrical conductivity to a degree between that of a metal (such as copper) and that of an insulator (such as glass). Semiconductors are the foundation of modern solid state electronics, including transistors, solar cells, light-emitting diodes (LEDs), quantum dots and digital and analog integrated circuits. A semiconductor may have a number of unique properties, one of which is the

170

Chemical vapor deposition of amorphous semiconductor films. Final subcontract report  

SciTech Connect (OSTI)

Chemical vapor deposition (CVD) from higher order silanes has been studied for fabricating amorphous hydrogenated silicon thin-film solar cells. Intrinsic and doped a-Si:H films were deposited in a reduced-pressure, tubular-flow reactor, using disilane feed-gas. Conditions for depositing intrinsic films at growth rates up to 10 A/s were identified. Electrical and optical properties, including dark conductivity, photoconductivity, activation energy, optical absorption, band-gap and sub-band-gap absorption properties of CVD intrinsic material were characterized. Parameter space for depositing intrinsic and doped films, suitable for device analysis, was identified.

Rocheleau, R.E.

1984-12-01T23:59:59.000Z

171

Semiconductor radiation detector  

DOE Patents [OSTI]

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.

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

172

Ternary Cobalt Spinel Oxides for Solar Driven Hydrogen Production: Theory and Experiment  

SciTech Connect (OSTI)

Discovery of a chemically stable, light absorbing and low resistivity metal oxide with band edges aligned to the water redox potentials has been a goal of physical scientists for the past forty years. Despite an immense amount of effort, no solution has been uncovered. We present a combined theoretical and experimental exploration of a series of unconventional ternary cobalt spinel oxides, which offer chemical functionality through substitution on the octahedral spinel B site. First-principles predictions of the substitution of group 13 cations (Al, Ga, In) in Co{sub 3}O{sub 4} to form a series of homologous CoX{sub 2}O{sub 4} spinel compounds are combined with experimental synthesis and photoelectrochemical characterization. Ultimately, while tunable band gaps in the visible range can be obtained, the material performance is limited by poor carrier transport properties associated with small polaron carriers. Future design pathways for metal oxide exploration are discussed.

Walsh, A.; Ahn, K. S.; Shet, S.; Huda, M. N.; Deutsch, T. G.; Wang, H.; Turner, J. A.; Wei, S. H.; Yan, Y.; Al-Jassim, M. M.

2009-01-01T23:59:59.000Z

173

Hybrid Semiconductors for Hardier Electronics and Optoelectronics? |  

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

Unveiling the Molecular Structure of the Target of Many Drugs Unveiling the Molecular Structure of the Target of Many Drugs A New Scenario for First Life on Earth Surface Orbital 'Roughness' in Colossal Magnetoresistive Oxide Different Roads Toward Quantum Criticality Orbital Reconstruction at a Complex Oxide Interface Science Highlights Archives: 2013 | 2012 | 2011 | 2010 2009 | 2008 | 2007 | 2006 2005 | 2004 | 2003 | 2002 2001 | 2000 | 1998 | Subscribe to APS Science Highlights rss feed Hybrid Semiconductors for Hardier Electronics and Optoelectronics? DECEMBER 21, 2007 Bookmark and Share The crystal structure of β-ZnTe(en)0:5, determined by single-crystal x-ray diffraction. Two-monolayerthick ZnTe slabs are interconnected by ethylenediamine (C2N2H8) molecules bonded to zinc atoms. Zn-Green, Te-Red, N-Blue,and C-Gray. Hydrogen atoms are omitted for clarity.

174

Method of passivating semiconductor surfaces  

DOE Patents [OSTI]

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.

Wanlass, Mark W. (Golden, CO)

1990-01-01T23:59:59.000Z

175

Solvothermal synthesis of a bimetallic thiometallate containing germanium in two oxidation states  

SciTech Connect (OSTI)

A new layered germanium-antimony sulphide, [Ge(C{sub 2}N{sub 2}H{sub 8}){sub 3}][GeSb{sub 2}S{sub 6}], has been prepared at 463 K under solvothermal conditions in the presence of ethylenediamine. The compound has been characterised by single-crystal X-ray diffraction, thermogravimetry, elemental analysis and reflectance spectroscopy. [Ge(C{sub 2}N{sub 2}H{sub 8}){sub 3}][GeSb{sub 2}S{sub 6}] crystallises in the space group Pbca (a=13.3284(5), b=17.4801(6), c=18.5447(7) A). The structure consists of cyclic [GeSb{sub 2}S{sub 8}]{sup 6-} units that form chains which are cross-linked through Sb{sub 2}S{sub 2} rings to generate layers of stoichiometry [GeSb{sub 2}S{sub 6}]{sup 2-}, between which [Ge(en){sub 3}]{sup 2+} cations are located. [Ge(C{sub 2}N{sub 2}H{sub 8}){sub 3}][GeSb{sub 2}S{sub 6}] contains germanium in both the divalent and tetravalent states. The optical band gap of 2.49(4) eV is in excellent agreement with the value expected on the basis of the correlation with the density of metal centres previously identified for thioantimonates, and is consistent with states at the top of the valence band being predominantly of sulphur 3p character. - Graphical abstract: [Ge(C{sub 2}N{sub 2}H{sub 8}){sub 3}][GeSb{sub 2}S{sub 6}] is a mixed valent germanium compound that contains [GeSb{sub 2}S{sub 8}]{sup 6-} units cross linked through Sb{sub 2}S{sub 2} units to generate layers. Highlights: Black-Right-Pointing-Pointer Preparation and structural characterisation of a new mixed-metal thiometallate. Black-Right-Pointing-Pointer Germanium present in two oxidation states. Black-Right-Pointing-Pointer Optical band gap of 2.49(4) eV. Black-Right-Pointing-Pointer Band gap conforms to a correlation between band gap and density of metal centres.

Powell, Anthony V., E-mail: a.v.powell@hw.ac.uk [Department of Chemistry, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom); Mackay, Rosalyn [Department of Chemistry, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom)

2011-12-15T23:59:59.000Z

176

Semiconductor devices incorporating multilayer interference regions  

DOE Patents [OSTI]

A semiconductor high reflector comprising a number of thin alternating layers of semiconductor materials is electrically tunable and may be used as a temperature insensitive semiconductor laser in a Fabry-Perot configuration. 8 figs.

Biefeld, R.M.; Drummond, T.J.; Gourley, P.L.; Zipperian, T.E.

1987-08-31T23:59:59.000Z

177

Synthesis and photocatalytic applications of nano-sized zinc-doped mesoporous titanium oxide  

SciTech Connect (OSTI)

Graphical abstract: Nano-sized mesoporous titanium oxide (T0) and zinc-doped nano-sized mesoporous titanium oxides (TA–TD) were synthesized by a simple method and characterized by different techniques. All materials have been studied in the photocatalytic degradation of methylene blue under UV light, observing that the decrease in the band gap of the materials seems to have a positive influence in the photocatalytic activity. Display Omitted Highlights: ? Nano-sized mesoporous TiO{sub 2} and Zn-doped TiO{sub 2} have been synthesized and characterized. ? Band gap of the Zn-doped TiO{sub 2} decreases when the Zn amount increases. ? Materials consist of porous particles (10–20 nm). ? The photocatalytic degradation of MB has been studied for these materials. ? A decrease in the band gap of the materials enhances the photocatalytic activity. -- Abstract: The synthesis of nano-sized mesoporous titanium oxide (T0) is described by an easy synthetic method which consists of the reaction of titanium tetraisopropoxide and a solution of HNO{sub 3} in water (pH 2.0) and the subsequent elimination of the volatiles by simple distillation. On the other hand, zinc-doped mesoporous titanium oxides (TA–TD) were synthesized using the same method but adding increasing amounts of Zn(NO{sub 3}){sub 2} to give materials which contain between 0.12 and 6.17 wt.% Zn. Upon the calcinations of all the obtained materials, characterization has been carried out by using N{sub 2} adsorption–desorption isotherms, powder X-ray diffraction, X-ray fluorescence, UV–vis spectrometry, solid state {sup 47,49}Ti NMR spectroscopy and transmission electronic microscopy (TEM). The results show that all these materials are mesoporous, with BET surfaces between 54 and 121 m{sup 2}/g and similar pore diameters between 6.4 and 9.1 nm. XRD studies show that these materials mainly consist of anatase and very small amounts of brookite. TEM technique shows the small particle sizes of the corresponding materials (from 10 to 20 nm) and the porous structure of parallel and straight channels for T0, TA, TB and TC while the order in the porosity of the system is lost in TD. In addition, studies of the Kubelka-Munk function show that the band gap energy of the synthesized materials decreases with the increase of the Zn amount of the material from 3.24 (for T0) to 2.91 eV (for TD). All the studied materials have been studied in the photocatalytic degradation of methylene blue (MB) under UV light, observing that the decrease in the band gap of the materials seems to have a positive influence in the photocatalytic activity.

Sánchez-Muñoz, Sergio; Pérez-Quintanilla, Damián [Departamento de Química Inorgánica y Analítica, E.S.C.E.T., Universidad Rey Juan Carlos, C/Tulipán s/n, 28933, Móstoles (Madrid) (Spain)] [Departamento de Química Inorgánica y Analítica, E.S.C.E.T., Universidad Rey Juan Carlos, C/Tulipán s/n, 28933, Móstoles (Madrid) (Spain); Gómez-Ruiz, Santiago, E-mail: santiago.gomez@urjc.es [Departamento de Química Inorgánica y Analítica, E.S.C.E.T., Universidad Rey Juan Carlos, C/Tulipán s/n, 28933, Móstoles (Madrid) (Spain)] [Departamento de Química Inorgánica y Analítica, E.S.C.E.T., Universidad Rey Juan Carlos, C/Tulipán s/n, 28933, Móstoles (Madrid) (Spain)

2013-02-15T23:59:59.000Z

178

Avalanche semiconductor radiation detectors  

SciTech Connect (OSTI)

Operation of novel avalanche semiconductor detector, produced on the basis of heterojunctions Si-SiC and Si-Si{sub x}O{sub y} is described. A uniform avalanche process with gain from 10{sup 3} to 10{sup 5} can be reached depending on the conductivity of SiC and Si{sub x}O{sub y} layers. Two types of avalanche photodetectors designed for applications in wavelength range 500--10,00 nm with quantum efficiency 60 {+-} 10% (650 nm) and 200--700 nm with quantum efficiency 60 {+-} 15% (450 nm) are presented.

Sadygov, Z.Y. [Joint Inst. for Nuclear Research, Dubna (Russian Federation)] [Joint Inst. for Nuclear Research, Dubna (Russian Federation); [Azerbaijan Academy of Sciences, Baku (Azerbaijan). Physics Inst.; Zheleznykh, I.M.; Kirillova, T.A. [Russian Academy of Sciences, Moscow (Russian Federation). Inst. for Nuclear Research] [Russian Academy of Sciences, Moscow (Russian Federation). Inst. for Nuclear Research; Malakhov, N.A.; Jejer, V.N. [Joint Inst. for Nuclear Research, Dubna (Russian Federation)] [Joint Inst. for Nuclear Research, Dubna (Russian Federation)

1996-06-01T23:59:59.000Z

179

E-Print Network 3.0 - al-doped zinc oxide Sample Search Results  

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

magnetic semiconductors 3,4. In particular, transpar- ent conductive oxide (TCO) electrodes using Al-doped... - electronic devices, we investigated aluminum-doped...

180

Method Of Transferring Strained Semiconductor Structures  

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

Of Transferring Strained Semiconductor Structures Of Transferring Strained Semiconductor Structures Method Of Transferring Strained Semiconductor Structures The transfer of strained semiconductor layers from one substrate to another substrate involves depositing a multilayer structure on a substrate having surface contaminants. June 25, 2013 Method Of Transferring Strained Semiconductor Structures The transfer of strained semiconductor layers from one substrate to another substrate involves depositing a multilayer structure on a substrate having surface contaminants. Available for thumbnail of Feynman Center (505) 665-9090 Email Method Of Transferring Strained Semiconductor Structures The transfer of strained semiconductor layers from one substrate to another substrate involves depositing a multilayer structure on a substrate having

Note: This page contains sample records for the topic "band-gap semiconductor oxide" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Semiconductor Physics at the Optical Sciences Center  

Science Journals Connector (OSTI)

This talk reviews semiconductor physics experiments and theory at the Optical Sciences Center including optical bistability, femtosecond dynamics, as well as semiconductor laser...

Koch, Stephan W

182

Opportunities for Wide Bandgap Semiconductor Power Electronics...  

Energy Savers [EERE]

Opportunities for Wide Bandgap Semiconductor Power Electronics for Hydrogen and Fuel Cell Applications Opportunities for Wide Bandgap Semiconductor Power Electronics for Hydrogen...

183

Process for producing chalcogenide semiconductors  

DOE Patents [OSTI]

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.

Noufi, R.; Chen, Y.W.

1985-04-30T23:59:59.000Z

184

Thermal ionization induced metal-semiconductor transition and room temperature ferromagnetism in trivalent doped ZnO codoped with lithium  

SciTech Connect (OSTI)

Thermal ionization induced metallic to semiconductor (MST) transition occurring at 460?K for Zn{sub 0.97}Al{sub 0.03}O, 463?K for Zn{sub 0.94}Al{sub 0.03}Li{sub 0.03}O, and 503?K for Zn{sub 0.91}Al{sub 0.03}Li{sub 0.03}Mn{sub 0.03}O has been found in the sol-gel synthesized (using hexamethylenetetramine), trivalent doped (Al, Mn) ZnO codoped with lithium. Increase in the thermally ionized carrier concentration due to Al doping is responsible for near band edge (NBE) peak shift causing Fermi level to move into conduction band making it metallic consistent with resistivity results. Free carrier (thermally activated) neutralization with ionized donor is responsible for semiconducting nature, which is supported from the free carrier screening produced energy shift in the NBE of photoluminescence peak. Furthermore, independently band gap shrinkage is also obtained from UV-Visible studies confirming localization induced MST. An anti-correlation is found between defect density (DLE) and room temperature ferromagnetism (RTFM) indicating intrinsic defects are not directly responsible for RTFM.

Sivagamasundari, A.; Chandrasekar, S.; Pugaze, R.; Kannan, R., E-mail: kannan@pec.edu [Department of Physics, Pondicherry Engineering College, Puducherry 605 014 (India); Rajagopan, S. [Department of Chemistry, Pondicherry Engineering College, Puducherry 605 014 (India)

2014-03-07T23:59:59.000Z

185

Effect of Thermal Neutron Irradiation on Oxide Catalysts for the Decomposition of Nitrous Oxide  

Science Journals Connector (OSTI)

... alpha-particles which are produced by an (n, a) reaction with lithium-6 or boron-10 atoms. Nickel oxide contains excess oxygen ions as a £-type semiconductor and probably ...

YASUKAZU SAITO; YUKIO YONEDA; SHOJI MAKISHIMA

1959-02-07T23:59:59.000Z

186

Metal-semiconductor hybrid thin films in field-effect transistors  

SciTech Connect (OSTI)

Metal-semiconductor hybrid thin films consisting of an amorphous oxide semiconductor and a number of aluminum dots in different diameters and arrangements are formed by electron beam lithography and employed for thin-film transistors (TFTs). Experimental and computational demonstrations systematically reveal that the field-effect mobility of the TFTs enhances but levels off as the dot density increases, which originates from variations of the effective channel length that strongly depends on the electric field distribution in a transistor channel.

Okamura, Koshi, E-mail: koshi.okamura@kit.edu; Dehm, Simone [Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe (Germany)] [Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe (Germany); Hahn, Horst [Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe (Germany) [Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe (Germany); KIT-TUD Joint Research Laboratory Nanomaterials, Technische Universität Darmstadt, Petersenstr. 32, 64287 Darmstadt (Germany)

2013-12-16T23:59:59.000Z

187

Semiconductor radiation detector  

DOE Patents [OSTI]

A semiconductor detector for ionizing electromagnetic radiation, neutrons, and energetic charged particles. The detecting element is comprised of a compound having the composition I-III-VI.sub.2 or II-IV-V.sub.2 where the "I" component is from column 1A or 1B of the periodic table, the "II" component is from column 2B, the "III" component is from column 3A, the "IV" component is from column 4A, the "V" component is from column 5A, and the "VI" component is from column 6A. The detecting element detects ionizing radiation by generating a signal proportional to the energy deposited in the element, and detects neutrons by virtue of the ionizing radiation emitted by one or more of the constituent materials subsequent to capture. The detector may contain more than one neutron-sensitive component.

Bell, Zane W. (Oak Ridge, TN); Burger, Arnold (Knoxville, TN)

2010-03-30T23:59:59.000Z

188

Web Growth of Semiconductors  

Science Journals Connector (OSTI)

A novel process for growth of diamond?lattice semiconductors is described and a model is proposed for the growth mechanism. For germanium the process yields extended thin flat sheets typically 1 cm wide and 0.1 mm thick of good crystalline quality and relatively flat {111} surfaces. The sheet or web freezes from a liquid film drawn up by surface tension between two coplanar dendrites which originate from a single seed and are grown from the melt simultaneously with the sheet. Resistivity throughout the sheet is quite uniform. Etching of germanium webs shows them to be essentially dislocation?free and does not reveal any microsegregation of impurities. Silicon and indium antimonide have also been grown in this manner.

S. O'Hara; A. I. Bennett

1964-01-01T23:59:59.000Z

189

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

DOE Patents [OSTI]

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.

Sopori, Bhushan; Rangappan, Anikara

2014-11-25T23:59:59.000Z

190

Mathematical Modeling of Semiconductor Devices  

E-Print Network [OSTI]

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

Jüngel, Ansgar

191

Seebeck coefficient in organic semiconductors  

E-Print Network [OSTI]

Seebeck coefficient in organic semiconductors A dissertation submitted for the degree of Doctor of Philosophy Deepak Venkateshvaran Fitzwilliam College & Optoelectronics Group, Cavendish Laboratory University of Cambridge February 2014 “The end...

Venkateshvaran, Deepak

2014-07-01T23:59:59.000Z

192

A Low Temperature Fully Lithographic Process For Metal–Oxide Field-Effect Transistors  

E-Print Network [OSTI]

We report a low temperature ( ~ 100à °C) lithographic method for fabricating hybrid metal oxide/organic field-effect transistors (FETs) that combine a zinc-indium-oxide (ZIO) semiconductor channel and organic, parylene, ...

Sodini, Charles G.

193

Wide-Bandgap Semiconductors  

SciTech Connect (OSTI)

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.

Chinthavali, M.S.

2005-11-22T23:59:59.000Z

194

Semiconductor structures having electrically insulating and conducting portions formed from an AlSb-alloy layer  

DOE Patents [OSTI]

The semiconductor structure comprises a plurality of semiconductor layers formed on a substrate including at least one layer of a III-V compound semiconductor alloy comprising aluminum (Al) and antimony (Sb), with at least a part of the AlSb-alloy layer being chemically converted by an oxidation process to form superposed electrically insulating and electrically conducting portions. The electrically insulating portion formed from the AlSb-alloy layer comprises an oxide of aluminum (e.g., Al{sub 2}O{sub 3}), while the electrically conducting portion comprises Sb. A lateral oxidation process allows formation of the superposed insulating and conducting portions below monocrystalline semiconductor layers for forming many different types of semiconductor structures having particular utility for optoelectronic devices such as light-emitting diodes, edge-emitting lasers, vertical-cavity surface-emitting lasers, photodetectors and optical modulators (waveguide and surface normal), and for electronic devices such as heterojunction bipolar transistors, field-effect transistors and quantum-effect devices. The invention is expected to be particularly useful for forming light-emitting devices for use in the 1.3--1.6 {mu}m wavelength range, with the AlSb-alloy layer acting to define an active region of the device and to effectively channel an electrical current therein for efficient light generation. 10 figs.

Spahn, O.B.; Lear, K.L.

1998-03-10T23:59:59.000Z

195

Optical Properties and Potential Applications of Doped Semiconductor...  

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

Optical Properties and Potential Applications of Doped Semiconductor Nanoparticles. Optical Properties and Potential Applications of Doped Semiconductor Nanoparticles. Abstract:...

196

Electromagnetic compatibility in semiconductor manufacturing  

SciTech Connect (OSTI)

Electromagnetic Interference (EMI) causes problems in semiconductor manufacturing facilities that range from nuisances to major disruptions of production. In many instances, these issues are addressed in a reactionary rather than proactive manner by individuals who do not have the experience or the equipment necessary to combat EMI problems in a timely, cost effective manner. This approach leads to expensive retrofits, reduced equipment availability, long recovery times, and in some cases, line yield impacts. The goal of electromagnetic compatibility (EMC) in semiconductor manufacturing is to ensure that semiconductor process, metrology, and support equipment operate as intended without being affected by electromagnetic disturbances either transmitted through air (radiated interference), or transferred into the equipment via a conductive media (conducted interference). Rather than being neglected until serious issues arise, EMC should be considered in the early stages of facility design, in order to gain the most benefit at the lowest cost.

Montoya, J.A. [Intel Corp., Hillsboro, OR (United States)

1995-12-31T23:59:59.000Z

197

Ultrafast carrier dynamics in semiconductor quantum dots  

Science Journals Connector (OSTI)

The dynamics of band-edge photoluminescence (PL) in CdS nanocrystals (NC’s) dispersed in a glass matrix are studied with the femtosecond up-conversion technique. The time-resolved PL spectra exhibit several discrete features (three of them are in the NC energy band gap) which are not pronounced in a cw PL spectrum. The initial stage of a PL decay is governed by a depopulation of the lowest extended states due to carrier trapping (localization) on the time scale of 1 ps. The low-energy bands originating from the extended-to-localized state transitions exhibit extremely fast buildup dynamics (rise time is 400–700 fs) which is explained by the preexisting occupation of the localized states. © 1996 The American Physical Society.

V. Klimov; P. Haring Bolivar; H. Kurz

1996-01-15T23:59:59.000Z

198

Ferric oxide quantum dots in stable phosphate glass system and their magneto-optical study  

SciTech Connect (OSTI)

Graphical abstract: We report synthesis of ferric oxide embedded low melting phosphate glass nanocomposite and also the effect of ferric oxide nanoparticles (NCs) content on the optical and magneto-optical properties of the glasses. Faraday rotation of the glass nanocomposites was measured and showed variation in Verdet constant with concentration of ferric oxide. Interestingly, the host glass itself showed fairly good Verdet constant (11.5°/T cm) and there is a threefold enhancement in the Verdet constant of ferric oxide quantum dot-glass nanocomposite. Highlights: ? We synthesize ferric oxide embedded low melting stable phosphate glass nanocomposite. ? Glasses doped with 0.25 and 2% ferric oxide show particle size in the range of 4–12 nm. ? The host phosphate glass itself shows fairly good Verdet constant (11.5°/T cm). ? Glasses doped with 0.25% ferric oxide show high Verdet constant (30.525°/T cm). ? The as synthesis glasses may have potential application in magneto optical devices. -- Abstract: Herein, we report the synthesis of ferric oxide embedded low melting phosphate glass nanocomposite and also the effect of ferric oxide nanoparticles content on the optical and magneto-optical properties of the glasses. The optical study clearly showed red shift in optical cut off with increasing ferric oxide concentration. The band gap of the host glass was observed to be 3.48 eV and it shifted to 3.14 eV after doping with ferric oxide. The glasses doped with 0.25 and 2% ferric oxide showed particle size of 4–6 nm and 8–12 nm, respectively. Faraday rotation of the glass nanocomposites was measured and showed variation in the Verdet constant as per increasing concentration of ferric oxide. Interestingly, the host glass itself showed fairly good Verdet constant (11.5°/T cm) and threefold enhancement was observed in the Verdet constant of ferric oxide quantum dot-glass nanocomposite.

Garaje, Sunil N.; Apte, Sanjay K. [Nanocomposite Group, Centre for Materials for Electronics Technology (C-MET), Department of Electronics and Information Technology (DeitY), Government of India, Panchawati, Off Pashan Road, Pune 411008 (India)] [Nanocomposite Group, Centre for Materials for Electronics Technology (C-MET), Department of Electronics and Information Technology (DeitY), Government of India, Panchawati, Off Pashan Road, Pune 411008 (India); Kumar, Ganpathy [Department of Electrical and Computer Engineering, Tennessee Technological University, 1 William L. Jones Drive, Cookeville, TN 38505 (United States)] [Department of Electrical and Computer Engineering, Tennessee Technological University, 1 William L. Jones Drive, Cookeville, TN 38505 (United States); Panmand, Rajendra P.; Naik, Sonali D. [Nanocomposite Group, Centre for Materials for Electronics Technology (C-MET), Department of Electronics and Information Technology (DeitY), Government of India, Panchawati, Off Pashan Road, Pune 411008 (India)] [Nanocomposite Group, Centre for Materials for Electronics Technology (C-MET), Department of Electronics and Information Technology (DeitY), Government of India, Panchawati, Off Pashan Road, Pune 411008 (India); Mahajan, Satish M., E-mail: smahajan@tntech.edu [Department of Electrical and Computer Engineering, Tennessee Technological University, 1 William L. Jones Drive, Cookeville, TN 38505 (United States); Chand, Ramesh [Ministry of Communications and Information Technology, Department of Electronics and Information Technology (DeitY), Electronics Niketan, 6, CGO Complex, New Delhi 110003 (India)] [Ministry of Communications and Information Technology, Department of Electronics and Information Technology (DeitY), Electronics Niketan, 6, CGO Complex, New Delhi 110003 (India); Kale, Bharat B., E-mail: bbkale@cmet.gov.in [Nanocomposite Group, Centre for Materials for Electronics Technology (C-MET), Department of Electronics and Information Technology (DeitY), Government of India, Panchawati, Off Pashan Road, Pune 411008 (India)

2013-02-15T23:59:59.000Z

199

Semiconductor nanocrystal-based phagokinetic tracking  

DOE Patents [OSTI]

Methods for determining metabolic properties of living cells through the uptake of semiconductor nanocrystals by cells. Generally the methods require a layer of neutral or hydrophilic semiconductor nanocrystals and a layer of cells seeded onto a culture surface and changes in the layer of semiconductor nanocrystals are detected. The observed changes made to the layer of semiconductor nanocrystals can be correlated to such metabolic properties as metastatic potential, cell motility or migration.

Alivisatos, A Paul; Larabell, Carolyn A; Parak, Wolfgang J; Le Gros, Mark; Boudreau, Rosanne

2014-11-18T23:59:59.000Z

200

Semiconductor electrode with improved photostability characteristics  

DOE Patents [OSTI]

An electrode is described for use in photoelectrochemical cells having an electrolyte which includes an aqueous constituent. The electrode consists of a semiconductor and a hydrophobic film disposed between the semiconductor and the aqueous constituent. The hydrophobic film is adapted to permit charges to pass therethrough while substantially decreasing the activity of the aqueous constituent at the semiconductor surface thereby decreasing the photodegradation of the semiconductor electrode.

Frank, A.J.

1985-02-19T23:59:59.000Z

Note: This page contains sample records for the topic "band-gap semiconductor oxide" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Performance of solid oxide fuel cells approaching the two-dimensional limit  

Science Journals Connector (OSTI)

We model electrochemical kinetics and physical conduction mechanisms for carrier transport in electrolyte membranes to determine the limits of dimensionality reduction (down to 1?nm) on maximum power output of solid oxide fuel cells with symmetric Pt electrodes. Using Y-doped ZrO2 we find a minimum thickness of ?6?nm to realize near ideal chemical potential in such fuel cells which is limited by electronic breakdown when approaching the dielectric breakdown strength. For larger electrolyte thicknesses the greatest source of electronic leakage influencing power loss is from Ohmic transport of minority carriers and emission of trapped carriers. For porous metallic electrodes an ideal microstructure with the particle size comparable to particle spacing dimensions is found to accurately model experimental results. The role of electronic trap states in the electrolyte band gap on power density characteristics is highlighted.

K. Kerman; S. Ramanathan

2014-01-01T23:59:59.000Z

202

Physical properties of erbium implanted tungsten oxide filmsdeposited by reactive dual magnetron sputtering  

SciTech Connect (OSTI)

Amorphous and partially crystalline WO3 thin films wereprepared by reactive dual magnetron sputtering and successively implantedby erbium ions with a fluence in the range from 7.7 x 1014 to 5 x 1015ions/cm2. The electrical and optical properties were studied as afunction of the film deposition parameters and the ion fluence. Ionimplantation caused a strong decrease of the resistivity, a moderatedecrease of the index of refraction and a moderate increase of theextinction coefficient in the visible and near infrared, while theoptical band gap remained almost unchanged. These effects could belargely ascribed to ion-induced oxygen deficiency. When annealed in air,the already low resistivities of the implanted samples decreased furtherup to 70oC, whereas oxidation, and hence a strong increase of theresistivity, was observed at higher annealing temperatures.

Mohamed, Sodky H.; Anders, Andre

2006-11-08T23:59:59.000Z

203

Semiconductor-based optical refrigerator  

DOE Patents [OSTI]

Optical refrigerators using semiconductor material as a cooling medium, with layers of material in close proximity to the cooling medium that carries away heat from the cooling material and preventing radiation trapping. In addition to the use of semiconducting material, the invention can be used with ytterbium-doped glass optical refrigerators.

Epstein, Richard I. (Santa Fe, NM); Edwards, Bradley C. (Nekoosa, WI); Sheik-Bahae, Mansoor (Albuquerque, NM)

2002-01-01T23:59:59.000Z

204

Mechanical scriber for semiconductor devices  

DOE Patents [OSTI]

A mechanical scriber using a scribing tip, such as a diamond, provides controlled scriber forces with a spring-loaded compound lever arrangement. The scribing force and range of scribing depth are adjusted by a pair of adjustable micrometer heads. A semiconductor device, such as a multilayer solar cell, can be formed into scribed strips at each layer. 5 figs.

Lin, P.T.

1985-03-05T23:59:59.000Z

205

Hybrid structure laser based on semiconductor nanowires and a silica microfiber knot cavity  

E-Print Network [OSTI]

.1063/1.3093821 Semiconductor lasers based on cadmium sulfide CdS , zinc oxide ZnO , gallium nitride GaN nanowires, and gal-earth doped microfiber knot laser with knot diameter below 1 mm failed due to the insufficient pump absorption

Wu, Shin-Tson

206

Molecular dynamics simulation comparison of atomic scale intermixing at the amorphous Al2O3/semiconductor interface for a-Al2O3/Ge, a-Al2O3/InGaAs,  

E-Print Network [OSTI]

Molecular dynamics simulation comparison of atomic scale intermixing at the amorphous Al2O3/semiconductor interface for a-Al2O3/Ge, a-Al2O3/InGaAs, and a-Al2O3/InAlAs/InGaAs Evgueni A. Chagarov *, Andrew oxides Ge InGaAs InAlAs Oxide­semiconductor stack High-K oxide a b s t r a c t The structural properties

Kummel, Andrew C.

207

Band structure properties of (BGa)P semiconductors for lattice matched integration on (001) silicon  

SciTech Connect (OSTI)

We report the band structure properties of (BGa)P layers grown on silicon substrate using metal-organic vapour-phase epitaxy. Using surface photo-voltage spectroscopy we find that both the direct and indirect band gaps of (BGa)P alloys (strained and unstrained) decrease with Boron content. Our experimental results suggest that the band gap of (BGa)P layers up to 6% Boron is large and suitable to be used as cladding and contact layers in GaP-based quantum well heterostructures on silicon substrates.

Hossain, Nadir; Sweeney, Stephen [Advanced Technology Institute and Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom); Hosea, Jeff [Advanced Technology Institute and Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH, UK and Ibnu Sina Institute for Fundamental Science Studies, Universiti Teknologi Malaysia, Johor Bahru 81310 (Malaysia); Liebich, Sven; Zimprich, Martin; Volz, Kerstin; Stolz, Wolfgang [Material Sciences Center and Faculty of Physics, Philipps-University, 35032 Marburg (Germany); Kunert, Bernerdette [NAsP III/V GmbH, Am Knechtacker 19, 35041 Marburg (Germany)

2013-12-04T23:59:59.000Z

208

Semiconductor-To-Metal Transitions in Transition-Metal Compounds  

Science Journals Connector (OSTI)

The theory presented in a previous paper is applied to the transition-metal compounds which are known to exhibit semiconductor-to-metal transitions. In particular, the predictions of the theory are compared with the experimental results of Feinleib and Paul on V2O3. Very good agreement is obtained for the magnitude of the energy gap and for its pressure and stress coefficients. The theory appears to be consistent with the available data on the other oxides of vanadium and titanium as well. Band models for all of these compounds are suggested. The effects of spin-disorder scattering and broadening, polaron formation, and non-stoichiometry are considered quantitatively.

David Adler; Julius Feinleib; Harvey Brooks; William Paul

1967-03-15T23:59:59.000Z

209

Photovoltaic property of bismuth ferrite thin films and its application in non-volatile memory.  

E-Print Network [OSTI]

??In conventional junction-based photovoltaic cells, the photovoltage is usually smaller than the semiconductor band gap, due to the limitation of the energy barrier at the… (more)

Guo, Rui.

2013-01-01T23:59:59.000Z

210

Minding the Gap Makes for More Efficient Solar Cells  

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

properties of these materials go through a dramatic change that makes them ideal for solar energy applications. These materials can go from indirect band gap semiconductors to...

211

Passivating ligand and solvent contributions to the electronic properties of semiconductor nanocrystals  

SciTech Connect (OSTI)

We examine in detail the impact of passivating ligands (i.e., amines, phosphines, phosphine oxides and pyridines) on the electronic and optical spectra of Cd{sub 33}Se{sub 33} quantum dots (QDs) using density functional theory (DFT) and time-dependent DFT (TDDFT) quantum-chemical methodologies. Most ligand orbitals are found deep inside in the valence and conduction bands of the QD, with pyridine being an exception by introducing new states close to the conduction band edge. Importantly, all ligands contribute states which are highly delocalized over both the QD surface and ligands, forming hybridized orbitals rather than ligand-localized trap states. In contrast, the states close to the band gap are delocalized over the QD atoms only and define the lower energy absorption spectra. The random detachment of one of ligands from the QD surface results in the appearance of a highly localized unoccupied state inside the energy gap of the QD. Such changes in the electronic structure are correlated with the respective QD-ligand binding energy and steric ligand-ligand interactions. Polar solvent significantly reduces both effects leading to delocalization and stabilization of the surface states. Thus, trap and surface states are substantially eliminated by the solvent. Polar solvent also blue-shifts (e.g., 0.3-0.4 eV in acetonitrile) the calculated absorption spectra. This shift increases with an increase of the dielectric constant of the solvent. We also found that the approximate single-particle Kohn-Sham (KS) approach is adequate for calculating the absorption spectra of the ligated QDs. Besides a systematic blue-shift, the KS spectra are in very good agreement with their respective counterparts calculated with the more accurate TDDFT method.

Fischer, S.; Crotty, A.; Kilina, S.; Ivanov, I.; Tretiak, S

2012-01-01T23:59:59.000Z

212

Stretchable semiconductor elements and stretchable electrical circuits  

DOE Patents [OSTI]

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.

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

2009-07-07T23:59:59.000Z

213

Optical devices featuring textured semiconductor layers  

DOE Patents [OSTI]

A semiconductor sensor, solar cell or emitter, or a precursor therefor, has a substrate and one or more textured semiconductor layers deposited onto the substrate. The textured layers enhance light extraction or absorption. Texturing in the region of multiple quantum wells greatly enhances internal quantum efficiency if the semiconductor is polar and the quantum wells are grown along the polar direction. Electroluminescence of LEDs of the invention is dichromatic, and results in variable color LEDs, including white LEDs, without the use of phosphor.

Moustakas, Theodore D. (Dover, MA); Cabalu, Jasper S. (Cary, NC)

2012-08-07T23:59:59.000Z

214

Optical devices featuring textured semiconductor layers  

DOE Patents [OSTI]

A semiconductor sensor, solar cell or emitter, or a precursor therefor, has a substrate and one or more textured semiconductor layers deposited onto the substrate. The textured layers enhance light extraction or absorption. Texturing in the region of multiple quantum wells greatly enhances internal quantum efficiency if the semiconductor is polar and the quantum wells are grown along the polar direction. Electroluminescence of LEDs of the invention is dichromatic, and results in variable color LEDs, including white LEDs, without the use of phosphor.

Moustakas, Theodore D. (Dover, MA); Cabalu, Jasper S. (Cary, NC)

2011-10-11T23:59:59.000Z

215

Photon Statistics of Semiconductor Light Sources.  

E-Print Network [OSTI]

??In recent years, semiconductor light sources have become more and more interesting in terms of applications due to their high efficiency and low cost. Advanced… (more)

Aßmann, Marc

2010-01-01T23:59:59.000Z

216

Earth-abundant semiconductors for photovoltaic applications ...  

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

Earth-abundant semiconductors for photovoltaic applications Thin film photovoltaics (solar cells) has the potential to revolutionize our energy landscape by producing clean,...

217

Sandia National Labs: PCNSC: Research: Compound Semiconductor...  

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

and chemistry foundations to advance the state-of-the-art compound semiconductor optoelectronic materials and devices. Our approach is based on a focused effort including...

218

Wide Bandgap Semiconductors for Clean Energy Workshop  

Broader source: Energy.gov [DOE]

A workshop on Wide Bandgap (WBG) Semiconductors for Clean Energy (held July 25, 2012, in Chicago, Illinois) brought together stakeholders from industry and academia to discuss the technical status of WBG semiconductors. The workshop also explored emerging WBG market applications in clean energy and barriers to the development and widespread commercial use of WBG semiconductors. Improving the quality and reliability of WBG semiconductors—and reducing their manufacturing costs—could accelerate their use in automotive, power electronics, solid-state lighting, and other clean energy applications.

219

Low Energy Ion Implantationin Semiconductor Manufacturing | U...  

Office of Science (SC) Website

Low Energy Ion Implantation in Semiconductor Manufacturing Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Applications of Nuclear Science...

220

Climate VISION: Private Sector Initiatives: Semiconductors: Work...  

Office of Scientific and Technical Information (OSTI)

Plans The Semiconductor Industry Association has finalized its work plan with the collaboration of EPA. The plan describes actions the industry intends to take to achieve its...

Note: This page contains sample records for the topic "band-gap semiconductor oxide" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

CCEC Seminar Wireless Sensors for SemiconductorWireless Sensors for Semiconductor  

E-Print Network [OSTI]

CCEC Seminar Wireless Sensors for SemiconductorWireless Sensors for Semiconductor Manufacturing perhaps. In this talk, we describe our efforts in developing a new class of wireless sensors for use in semiconductor manufacturing. These sensors are fully self-contained with on board power, communications

Akhmedov, Azer

222

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

E-Print Network [OSTI]

33 vi UHV ExperimentalPAW PP k Si STM STS s W I t UHV VASP V XPS LIST OF FIGURESof the gas-scattering UHV chamber

Bishop, Sarah R.

2010-01-01T23:59:59.000Z

223

Acoustoelectric Interactions in Piezoelectric Semiconductors  

Science Journals Connector (OSTI)

Piezoelectric semiconductors such as cadmium sulfide exhibit a strong coupling between conduction electrons that are present in the substance and acoustic waves that are propagated along certain directions in the material. This energy exchange mechanism is highly nonlinear, and thus the simultaneous introduction of several collinear acoustic waves into the substance generates new signals at the conbination (sum and difference) frequencies. A theoretical explanation of this interaction mechanism, based on consideration of the nonlinear cross term present in the current-density equation, has been developed, and the validity of this method of analysis has been tested and qualitatively confirmed through experimentation.

R. Mauro and W. C. Wang

1970-01-15T23:59:59.000Z

224

Optic probe for semiconductor characterization  

DOE Patents [OSTI]

Described herein is an optical probe (120) for use in characterizing surface defects in wafers, such as semiconductor wafers. The optical probe (120) detects laser light reflected from the surface (124) of the wafer (106) within various ranges of angles. Characteristics of defects in the surface (124) of the wafer (106) are determined based on the amount of reflected laser light detected in each of the ranges of angles. Additionally, a wafer characterization system (100) is described that includes the described optical probe (120).

Sopori, Bhushan L. (Denver, CO); Hambarian, Artak (Yerevan, AM)

2008-09-02T23:59:59.000Z

225

Wet Chemical Functionalization of III–V Semiconductor Surfaces: Alkylation of Gallium Arsenide and Gallium Nitride by a Grignard Reaction Sequence  

Science Journals Connector (OSTI)

Wet Chemical Functionalization of III–V Semiconductor Surfaces: Alkylation of Gallium Arsenide and Gallium Nitride by a Grignard Reaction Sequence ... These observations are consistent with the known solubility of oxidized As species in water. ... Remote H plasma exposure was effective for removing halogens and hydrocarbons from the surfaces of both nitrides at 450 °C, but was not efficient for oxide removal. ...

Sabrina L. Peczonczyk; Jhindan Mukherjee; Azhar I. Carim; Stephen Maldonado

2012-02-28T23:59:59.000Z

226

Charge-carrier transport in amorphous organic semiconductors  

E-Print Network [OSTI]

Since the first reports of efficient luminescence and absorption in organic semiconductors, organic light-emitting devices (OLEDs) and photovoltaics (OPVs) have attracted increasing interest. Organic semiconductors have ...

Limketkai, Benjie, 1982-

2008-01-01T23:59:59.000Z

227

Comments on the National Technology Roadmap for Semiconductors  

Science Journals Connector (OSTI)

The SIA National Technology Roadmap for Semiconductors (NTRS) [1] represents ... in defining a unified description of the semiconductor technology requirements for ensuring advancements in the performance ... an ...

James F. Freedman

1996-01-01T23:59:59.000Z

228

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...

229

Engineering Density of States of Earth Abundant Semiconductors...  

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

Density of States of Earth Abundant Semiconductors for Enhanced Thermoelectric Power Factor Engineering Density of States of Earth Abundant Semiconductors for Enhanced...

230

Electronic Structure and Magnetism in Diluted Magnetic Semiconductors  

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

Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print Wednesday, 29 November 2006 00:00...

231

Wide Bandgap Semiconductors for Clean Energy Workshop Agenda  

Energy Savers [EERE]

Wide Bandgap Semiconductors for Clean Energy Workshop Wednesday, July 25, 2012 Hilton Rosemont O'Hare, Chicago, IL Introduction Wide bandgap (WBG) semiconductors operate at...

232

Webinar: Opportunities for Wide Bandgap Semiconductor Power Electronic...  

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

Opportunities for Wide Bandgap Semiconductor Power Electronics for Hydrogen and Fuel Cell Applications Webinar: Opportunities for Wide Bandgap Semiconductor Power Electronics for...

233

Webinar: Opportunities for Wide Bandgap Semiconductor Power Electronic...  

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

Webinar: Opportunities for Wide Bandgap Semiconductor Power Electronics for Hydrogen and Fuel Cell Applications Webinar: Opportunities for Wide Bandgap Semiconductor Power...

234

Preparation of a semiconductor thin film  

DOE Patents [OSTI]

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.

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

235

Preparation of a semiconductor thin film  

DOE Patents [OSTI]

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.

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

1998-01-27T23:59:59.000Z

236

e! Science News Semiconductor manufacturing technique holds  

E-Print Network [OSTI]

arsenide chips manufactured in multilayer stacks: light sensors, high-speed transistors and solar cellse! Science News Semiconductor manufacturing technique holds promise for solar energy Published semiconductor manufacturing method pioneered at the University of Illinois, the future of solar energy just got

Rogers, John A.

237

Semiconductor heterojunction band offsets and charge neutrality  

E-Print Network [OSTI]

on semi- conductors A and B like Figure 3. 1, and commutativity of semiconductors A and B, i. e. , DEs(A ? B) = DE?(B ? A). (3. 33) We predict the charge neutrality levels &b, 4is and 4i, might align in semiconductors A, B and C as shown in Figure 3...

Lee, Chomsik

2012-06-07T23:59:59.000Z

238

Nano- sized strontium titanate metal oxide semiconductor oxygen gas sensors.  

E-Print Network [OSTI]

??The project focuses on strontium titanate (SrTiO3> material, a very important material for oxygen sensors. The advantages of the material are low cost and stability… (more)

Hu, Ying.

2008-01-01T23:59:59.000Z

239

Visible Light Water Splitting Using Dye-Sensitized Oxide Semiconductors  

E-Print Network [OSTI]

- ical energy in the form of fuels. Hydrogen is a key solar fuel because it can be used directly. This Account describes our approach to two problems in solar water splitting: the organization of molecules in photochemistry.1,2 Efficient photocatalytic water-splitting systems could have practical value for solar energy

240

Low interfacial trap density and sub-nm equivalent oxide thickness in In{sub 0.53}Ga{sub 0.47}As (001) metal-oxide-semiconductor devices using molecular beam deposited HfO{sub 2}/Al{sub 2}O{sub 3} as gate dielectrics  

SciTech Connect (OSTI)

We investigated the passivation of In{sub 0.53}Ga{sub 0.47}As (001) surface by molecular beam epitaxy techniques. After growth of strained In{sub 0.53}Ga{sub 0.47}As on InP (001) substrate, HfO{sub 2}/Al{sub 2}O{sub 3} high-{kappa} oxide stacks have been deposited in-situ after surface reconstruction engineering. Excellent capacitance-voltage characteristics have been demonstrated along with low gate leakage currents. The interfacial density of states (D{sub it}) of the Al{sub 2}O{sub 3}/In{sub 0.53}Ga{sub 0.47}As interface have been revealed by conductance measurement, indicating a downward D{sub it} profile from the energy close to the valence band (medium 10{sup 12} cm{sup -2}eV{sup -1}) towards that close to the conduction band (10{sup 11} cm{sup -2}eV{sup -1}). The low D{sub it}'s are in good agreement with the high Fermi-level movement efficiency of greater than 80%. Moreover, excellent scalability of the HfO{sub 2} has been demonstrated as evidenced by the good dependence of capacitance oxide thickness on the HfO{sub 2} thickness (dielectric constant of HfO{sub 2}{approx}20) and the remained low D{sub it}'s due to the thin Al{sub 2}O{sub 3} passivation layer. The sample with HfO{sub 2} (3.4 nm)/Al{sub 2}O{sub 3} (1.2 nm) as the gate dielectrics has exhibited an equivalent oxide thickness of {approx}0.93 nm.

Chu, L. K. [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Katholieke Universiteit Leuven, 3001 Leuven (Belgium); Merckling, C.; Dekoster, J.; Caymax, M. [Interuniversity Microelectronics Center (IMEC vzw), 3001 Leuven (Belgium); Alian, A.; Heyns, M. [Katholieke Universiteit Leuven, 3001 Leuven (Belgium); Interuniversity Microelectronics Center (IMEC vzw), 3001 Leuven (Belgium); Kwo, J. [Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Center for Condensed Matter Sciences, National Taiwan University, Taipei 10617, Taiwan (China); Hong, M. [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan (China)

2011-07-25T23:59:59.000Z

Note: This page contains sample records for the topic "band-gap semiconductor oxide" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Novel room temperature ferromagnetic semiconductors  

SciTech Connect (OSTI)

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.

Gupta, Amita

2004-11-01T23:59:59.000Z

242

E-Print Network 3.0 - al oxide films Sample Search Results  

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

in semiconductors produced by thermally oxidizing AlN thin films... O2 flow at 800 to 1100C for 1- 4 ... Source: Kolodzey, James - Department of Electrical and Computer...

243

Synchrotron x-ray reflectivity study of oxidation/passivation of copper and silicon.  

SciTech Connect (OSTI)

Synchrotron x-ray-scattering technique studies of copper and silicon electrochemical interfaces are reported. These two examples illustrate the application of synchrotron x-ray techniques for oxidation, passivation, and dissolution of metals and semiconductors.

Chu, Y.; Nagy, Z.; Parkhutik, V.; You, H.

1999-07-21T23:59:59.000Z

244

Low temperature lithographically patterned metal oxide transistors for large area electronics  

E-Print Network [OSTI]

Optically transparent, wide bandgap metal oxide semiconductors are a promising candidate for large-area electronics technologies that require lightweight, temperature-sensitive flexible substrates. Because these thin films ...

Wang, Annie I. (Annie I-Jen), 1981-

2011-01-01T23:59:59.000Z

245

Magnetoresistance and Microstructure of Magnetite Nanocrystals Dispersed in Indium?Tin Oxide Thin Films  

Science Journals Connector (OSTI)

Indium?tin oxide (ITO) is the most widely used TCO in the semiconductor and electronic device industries. ... NCs of inverse-spinel-type Fe3O4 grew epitaxially on the YSZ substrate, as shown in Figure 4. ...

Koichi Okada; Shigemi Kohiki; Masanori Mitome; Hidekazu Tanaka; Masao Arai; Masaki Mito; Hiroyuki Deguchi

2009-09-02T23:59:59.000Z

246

Investigation of the basic physics of high efficiency semiconductor hot carrier solar cell. Annual status report, 31 May 1994-30 May 1995  

SciTech Connect (OSTI)

The main purpose of this research program is to investigate potential semiconductor materials and their multi-band-gap MQW (multiple quantum wells) structures for high efficiency solar cells for aerospace and commercial applications. The absorption and PL (photoluminescence) spectra, the carrier dynamics, and band structures have been investigated for semiconductors of InP, GaP, GaInP, and InGaAsP/InP MQW structures, and for semiconductors of GaAs and AlGaAs by previous measurements. The barrier potential design criteria for achieving maximum energy conversion efficiency, and the resonant tunneling time as a function of barrier width in high efficiency MQW solar cell structures have also been investigated in the first two years. Based on previous carrier dynamics measurements and the time-dependent short circuit current density calculations, an InAs/InGaAs - InGaAs/GaAs - GaAs/AlGaAs MQW solar cell structure with 15 bandgaps has been designed. The absorption and PL spectra in InGaAsP/InP bulk and MQW structures were measured at room temperature and 77 K with different pump wavelength and intensity, to search for resonant states that may affect the solar cell activities. Time-resolved IR absorption for InGaAsP/InP bulk and MQW structures has been measured by femtosecond visible-pump and IR-probe absorption spectroscopy. This, with the absorption and PL measurements, will be helpful to understand the basic physics and device performance in multi-bandgap InAs/InGaAs - InGaAs/InP - InP/InGaP MQW solar cells. In particular, the lifetime of the photoexcited hot electrons is an important parameter for the device operation of InGaAsP/InP MQW solar cells working in the resonant tunneling conditions. Lastly, time evolution of the hot electron relaxation in GaAs has been measured in the temperature range of 4 K through 288 K using femtosecond pump-IR-probe absorption technique.

Alfano, R.R.; Wang, W.B.; Mohaidat, J.M.; Cavicchia, M.A.; Raisky, O.Y.

1995-05-01T23:59:59.000Z

247

Thin film solar cell including a spatially modulated intrinsic layer  

DOE Patents [OSTI]

One or more thin film solar cells in which the intrinsic layer of substantially amorphous semiconductor alloy material thereof includes at least a first band gap portion and a narrower band gap portion. The band gap of the intrinsic layer is spatially graded through a portion of the bulk thickness, said graded portion including a region removed from the intrinsic layer-dopant layer interfaces. The band gap of the intrinsic layer is always less than the band gap of the doped layers. The gradation of the intrinsic layer is effected such that the open circuit voltage and/or the fill factor of the one or plural solar cell structure is enhanced.

Guha, Subhendu (Troy, MI); Yang, Chi-Chung (Troy, MI); Ovshinsky, Stanford R. (Bloomfield Hills, MI)

1989-03-28T23:59:59.000Z

248

Semiconductor Nanoclusters as Potential Photocatalysts  

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

High Power Electronics Based on the 2-Dimensional Electron Gas in GaN High Power Electronics Based on the 2-Dimensional Electron Gas in GaN Heterostructures by S. R. Kurtz, A. A. Allerman, and D. Koleski Motivation-GaN-based electronics offer miniaturization potential of radical proportions for microwave power amplifiers. GaN's large bandgap, high breakdown field, high electron velocity, and excellent thermal properties have led to high electron mobility transistors (HEMT) with up to 10x the power density of GaAs and other traditional semiconductors at frequencies up to 20 GHz. Further contributing to the outstanding performance of GaN-based amplifiers is the highly conducting, 2-dimensional electron gas (2DEG) used for the HEMT channel. Intrinsic polarization and piezoelectric properties of GaN materials can produce a 2DEG at an

249

Energy Management in Semiconductor Cleanrooms  

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

6 6 Energy Management in Semiconductor Cleanrooms Cleanrooms are used extensively in the manufacturing of integrated circuits and in the biological and pharmaceutical industries. For particle concentrations to remain low, for example, less than 100 particles/ft3 at >0.5 micrometers (Class 100), the air in the cleanroom must be filtered. Typically, the air is circulated through high-efficiency particulate air (HEPA) filters at a very high rate, such as 400 to 600 room air volumes per hour, to maintain low particle concentrations. The combined effect of high recirculation and a high pressure drop through HEPA filters is higher power costs per unit floor area to operate the cleanroom than to ventilate a commercial building. Cleanrooms are usually ventilated constantly and

250

Boron doping a semiconductor particle  

DOE Patents [OSTI]

A method (10,30) of boron doping a semiconductor particle using boric acid to obtain a p-type doped particle. Either silicon spheres or silicon powder is mixed with a diluted solution of boric acid having a predetermined concentration. The spheres are dried (16), with the boron film then being driven (18) into the sphere. A melt procedure mixes the driven boron uniformly throughout the sphere. In the case of silicon powder, the powder is metered out (38) into piles and melted/fused (40) with an optical furnace. Both processes obtain a p-type doped silicon sphere with desired resistivity. Boric acid is not a restricted chemical, is inexpensive, and does not pose any special shipping, handling, or disposal requirements.

Stevens, Gary Don (18912 Ravenglen Ct., Dallas, TX 75287); Reynolds, Jeffrey Scott (703 Horizon, Murphy, TX 75094); Brown, Louanne Kay (2530 Poplar Tr., Garland, TX 75042)

1998-06-09T23:59:59.000Z

251

Heating device for semiconductor wafers  

DOE Patents [OSTI]

An apparatus for heat treating semiconductor wafers is disclosed. The apparatus includes a heating device which contains an assembly of light energy sources for emitting light energy onto a wafer. In particular, the light energy sources are positioned such that many different radial heating zones are created on a wafer being heated. For instance, in one embodiment, the light energy sources form a spiral configuration. In an alternative embodiment, the light energy sources appear to be randomly dispersed with respect to each other so that no discernable pattern is present. In a third alternative embodiment of the present invention, the light energy sources form concentric rings. Tuning light sources are then placed in between the concentric rings of light.

Vosen, Steven R. (Berkeley, CA)

1999-01-01T23:59:59.000Z

252

Heating device for semiconductor wafers  

DOE Patents [OSTI]

An apparatus for heat treating semiconductor wafers is disclosed. The apparatus includes a heating device which contains an assembly of light energy sources for emitting light energy onto a wafer. In particular, the light energy sources are positioned such that many different radial heating zones are created on a wafer being heated. For instance, in one embodiment, the light energy sources form a spiral configuration. In an alternative embodiment, the light energy sources appear to be randomly dispersed with respect to each other so that no discernible pattern is present. In a third alternative embodiment of the present invention, the light energy sources form concentric rings. Tuning light sources are then placed in between the concentric rings of light. 4 figs.

Vosen, S.R.

1999-07-27T23:59:59.000Z

253

AgBiS2 Semiconductor-Sensitized Solar Cells  

Science Journals Connector (OSTI)

AgBiS2 Semiconductor-Sensitized Solar Cells ... We present a new ternary semiconductor sensitizer-AgBiS2 for solar cells. ... Liquid-junction semiconductor-sensitized solar cells were fabricated from the synthesized AgBiS2 semiconductor. ...

Pen-Chi Huang; Wei-Chih Yang; Ming-Way Lee

2013-08-16T23:59:59.000Z

254

Transport Equations for Semiconductors Prof. Dr. Ansgar Jungel  

E-Print Network [OSTI]

- cations have been invented; for instance, semiconductor lasers, solar cells, light-emitting diodes (LED

Jüngel, Ansgar

255

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

E-Print Network [OSTI]

Topics: Fundamentals of Semiconductors; Theory of Electrical Conduction; Device Operations (See "Class

Massachusetts at Amherst, University of

256

Diluted magnetic semiconductor nanowires exhibiting magnetoresistance  

DOE Patents [OSTI]

A method for is disclosed for fabricating diluted magnetic semiconductor (DMS) nanowires by providing a catalyst-coated substrate and subjecting at least a portion of the substrate to a semiconductor, and dopant via chloride-based vapor transport to synthesize the nanowires. Using this novel chloride-based chemical vapor transport process, single crystalline diluted magnetic semiconductor nanowires Ga.sub.1-xMn.sub.xN (x=0.07) were synthesized. The nanowires, which have diameters of .about.10 nm to 100 nm and lengths of up to tens of micrometers, show ferromagnetism with Curie temperature above room temperature, and magnetoresistance up to 250 Kelvin.

Yang, Peidong (El Cerrito, CA); Choi, Heonjin (Seoul, KR); Lee, Sangkwon (Daejeon, KR); He, Rongrui (Albany, CA); Zhang, Yanfeng (El Cerrito, CA); Kuykendal, Tevye (Berkeley, CA); Pauzauskie, Peter (Berkeley, CA)

2011-08-23T23:59:59.000Z

257

Helicon wave excitation to produce energetic electrons for manufacturing semiconductors  

DOE Patents [OSTI]

A helicon plasma source is controlled by varying the axial magnetic field or rf power controlling the formation of the helicon wave. An energetic electron current is carried on the wave when the magnetic field is 90 G; but there is minimal energetic electron current when the magnetic field is 100 G in one particular plasma source. Similar performance can be expected from other helicon sources by properly adjusting the magnetic field and power to the particular geometry. This control for adjusting the production of energetic electrons can be used in the semiconductor and thin-film manufacture process. By applying energetic electrons to the insulator layer, such as silicon oxide, etching ions are attracted to the insulator layer and bombard the insulator layer at higher energy than areas that have not accumulated the energetic electrons. Thus, silicon and metal layers, which can neutralize the energetic electron currents will etch at a slower or non-existent rate. This procedure is especially advantageous in the multilayer semiconductor manufacturing because trenches can be formed that are in the range of 0.18-0.35 mm or less.

Molvik, Arthur W. (Livermore, CA); Ellingboe, Albert R. (Fremont, CA)

1998-01-01T23:59:59.000Z

258

Helicon wave excitation to produce energetic electrons for manufacturing semiconductors  

DOE Patents [OSTI]

A helicon plasma source is controlled by varying the axial magnetic field or rf power controlling the formation of the helicon wave. An energetic electron current is carried on the wave when the magnetic field is 90 G; but there is minimal energetic electron current when the magnetic field is 100 G in one particular plasma source. Similar performance can be expected from other helicon sources by properly adjusting the magnetic field and power to the particular geometry. This control for adjusting the production of energetic electrons can be used in the semiconductor and thin-film manufacture process. By applying energetic electrons to the insulator layer, such as silicon oxide, etching ions are attracted to the insulator layer and bombard the insulator layer at higher energy than areas that have not accumulated the energetic electrons. Thus, silicon and metal layers, which can neutralize the energetic electron currents will etch at a slower or non-existent rate. This procedure is especially advantageous in the multilayer semiconductor manufacturing because trenches can be formed that are in the range of 0.18--0.35 mm or less. 16 figs.

Molvik, A.W.; Ellingboe, A.R.

1998-10-20T23:59:59.000Z

259

Mospec Semiconductor Corp | Open Energy Information  

Open Energy Info (EERE)

Mospec Semiconductor Corp Mospec Semiconductor Corp Jump to: navigation, search Name Mospec Semiconductor Corp Place Tainan, Taiwan Sector Solar Product Taiwanese semiconductor products producer; offers monocrystalline silicon wafers and as of April 2008, ingots for the solar industry. Coordinates 22.99721°, 120.180862° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":22.99721,"lon":120.180862,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

260

Hemlock Semiconductor Corp HSC | Open Energy Information  

Open Energy Info (EERE)

Hemlock Semiconductor Corp HSC Hemlock Semiconductor Corp HSC Jump to: navigation, search Name Hemlock Semiconductor Corp (HSC) Place Hemlock, Michigan Zip 48626 Sector Solar Product US-based manufacturer polycrystalline silicon for semiconductor and solar industries. Coordinates 39.589497°, -82.153275° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":39.589497,"lon":-82.153275,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

Note: This page contains sample records for the topic "band-gap semiconductor oxide" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Climate VISION: Private Sector Initiatives: Semiconductors  

Office of Scientific and Technical Information (OSTI)

Letters of Intent/Agreements Letters of Intent/Agreements The U.S. semiconductor industry, represented by the members of the Environmental Protection Agency's PFC Reduction/Climate Partnership for the Semiconductor Industry, has committed to reduce absolute perfluorocompound (PFC) emissions by 10% below the 1995 baseline level by the year 2010. Perfluorocompounds include the most potent and long-lived greenhouse gases such as perfluorocarbons (e.g., CF4, C2F6, C3F8), trifluoromethane (CHF3), nitrogen trifluoride (NF3), and sulfur hexafluoride (SF6). The Environmental Protection Agency's (EPA) voluntary semiconductor industry partnership was developed collaboratively with the Semiconductor Industry Association (SIA). EPA, SIA, and the Partner companies (listed below) are working to reduce industry greenhouse gas (GHG) emissions. EPA's

262

Sandia National Laboratories: wide-bandgap semiconductor  

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

electroluminescence was first reported by H.J. Round in 1907, and the first light-emitting diode (LED) was reported by O.V. Losev in 1927. Not until the birth of semiconductor...

263

ITRS: The International Technology Roadmap for Semiconductors  

Science Journals Connector (OSTI)

In a move singular for the world’s industry, the semiconductor industry established a quantitative strategy for its progress with the establishment of the ITRS. In its 17th year, it has been extended in 2009 t...

Bernd Hoefflinger

2012-01-01T23:59:59.000Z

264

Wide Bandgap Semiconductors: Pursuing the Promise  

Broader source: Energy.gov [DOE]

Wide bandgap semiconductor materials are more efficient than their silicon-based counterparts; making it possible to reduce weight, volume, and life-cycle costs in a wide range of power applications.

265

Gaining creative control over semiconductor nanowires  

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

Gaining creative control over semiconductor nanowires Gaining creative control over semiconductor nanowires Gaining creative control over semiconductor nanowires Using a microfluidic reactor, Los Alamos researchers transformed the SLS process into a flow-based technique. September 26, 2013 Growth of nanowire precursors in a flowing carrier solvent Growth of nanowire precursors in a flowing carrier solvent The new "flow" solution-liquid-solid method allows scientists to slow down growth and thereby capture mechanistic details as the nanowires grow in solution. A Los Alamos research team has transformed the synthesis process of semiconductor nanowires for use in solar cells, batteries, electronics, sensors and photonics using a solution-liquid-solid (SLS) batch approach to achieve unprecedented control over growth rates, nanowire size and internal

266

Optical temperature indicator using thermochromic semiconductors  

DOE Patents [OSTI]

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.

Kronberg, J.W.

1995-01-01T23:59:59.000Z

267

All-optical logic gates based on vertical cavity semiconductor optical amplifiers  

E-Print Network [OSTI]

in International Technology Roadmap for Semiconductors 2007in International Technology Roadmap for Semiconductors 2007The 2007 International Technology Roadmap for Semiconductors

Gauss, Veronica Andrea

2009-01-01T23:59:59.000Z

268

E-Print Network 3.0 - area semiconductor laser Sample Search...  

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

areas of semiconductor... for conducting research on wide bandgap semiconductor optoelectronics in my research group, within the Center... bandgap III-Nitride semiconductor...

269

Electrolytic photodissociation of chemical compounds by iron oxide photochemical diodes  

DOE Patents [OSTI]

Chemical compounds can be dissociated by contacting the same with a p/n type semi-conductor photochemical diode having visible light as its sole source of energy. The photochemical diode consists of low cost, readily available materials, specifically polycrystalline iron oxide doped with silicon in the case of the n-type semi-conductor electrode, and polycrystalline iron oxide doped with magnesium in the case of the p-type electrode. So long as the light source has an energy greater than 2.2 electron volts, no added energy source is needed to achieve dissociation.

Somorjai, Gabor A. (Berkeley, CA); Leygraf, Christofer H. (Berkeley, CA)

1985-01-01T23:59:59.000Z

270

Electrolytic photodissociation of chemical compounds by iron oxide electrodes  

DOE Patents [OSTI]

Chemical compounds can be dissociated by contacting the same with a p/n type semi-conductor diode having visible light as its sole source of energy. The diode consists of low cost, readily available materials, specifically polycrystalline iron oxide doped with silicon in the case of the n-type semi-conductor electrode, and polycrystalline iron oxide doped with magnesium in the case of the p-type electrode. So long as the light source has an energy greater than 2.2 electron volts, no added energy source is needed to achieve dissociation.

Somorjai, Gabor A. (Berkeley, CA); Leygraf, Christofer H. (Berkeley, CA)

1984-01-01T23:59:59.000Z

271

Tuning laser-induced band gaps in graphene Hernn L. Calvo,1,2  

E-Print Network [OSTI]

Statistischen Physik, RWTH Aachen University, D-52056 Aachen, Germany 3 CIN2 (ICN­CSIC), Catalan Institute-infrared laser technology in a transport setup, thereby opening prom- ising prospects for graphene to the Dirac points K and K . Since we consider a clean sample and given that the ac field does not introduce

272

3+1 dimensional integrated optics with localized light in a photonic band gap  

E-Print Network [OSTI]

," Phys. Rev. Lett. 58, 2486­ 2489 (1987). 3. D. Wiersma, P. Bartolini, A. Lagendijk, and R. Righini

John, Sajeev

273

Broadband optical coupling between microstructured fibers and photonic band gap circuits: Two-dimensional paradigms  

E-Print Network [OSTI]

simple two-dimensional design models. We demonstrate an effective large- bandwidth small-footprint beam platform for integrated optics. Unlike conventional paradigms such as silicon on insulator SOI waveguides that guide light on a chip by total internal reflection index guiding , PBG-based microcircuits can guide

John, Sajeev

274

Fano-Hopfield model and photonic band gaps for an arbitrary atomic lattice  

SciTech Connect (OSTI)

We study the light dispersion relation in a periodic ensemble of atoms at fixed positions in the Fano-Hopfield model (the atomic dipole being modeled with harmonic oscillators). Compared to earlier works, we do not restrict to cubic lattices, and we do not regularize the theory by hand but we renormalize it in a systematic way using a Gaussian cutoff in momentum space. Whereas no omnidirectional spectral gap is known for light in a Bravais atomic lattice, we find that, for a wide range of parameters, an omnidirectional gap occurs in a diamond atomic lattice, which may be realized in an experiment with ultracold atoms. The long-wavelength limit of the theory also provides a Lorentz-Lorenz (or Clausius-Mossotti) relation for an arbitrary lattice.

Antezza, Mauro; Castin, Yvan [Laboratoire Kastler Brossel, Ecole Normale Superieure, CNRS and UPMC, 24 rue Lhomond, 75231 Paris (France)

2009-07-15T23:59:59.000Z

275

Fano-Hopfield model and photonic band gaps for an arbitrary atomic lattice  

Science Journals Connector (OSTI)

We study the light dispersion relation in a periodic ensemble of atoms at fixed positions in the Fano-Hopfield model (the atomic dipole being modeled with harmonic oscillators). Compared to earlier works, we do not restrict to cubic lattices, and we do not regularize the theory by hand but we renormalize it in a systematic way using a Gaussian cutoff in momentum space. Whereas no omnidirectional spectral gap is known for light in a Bravais atomic lattice, we find that, for a wide range of parameters, an omnidirectional gap occurs in a diamond atomic lattice, which may be realized in an experiment with ultracold atoms. The long-wavelength limit of the theory also provides a Lorentz-Lorenz (or Clausius-Mossotti) relation for an arbitrary lattice.

Mauro Antezza and Yvan Castin

2009-07-21T23:59:59.000Z

276

Final Report: Laser-Material Interactions Relevant to Analytic Spectroscopy of Wide Band Gap Materials  

SciTech Connect (OSTI)

We summarize our studies aimed at developing an understanding of the underlying physics and chemistry in terms of laser materials interactions relevant to laser-based sampling and chemical analysis of wide bandgap materials. This work focused on the determination of mechanisms for the emission of electrons, ions, atoms, and molecules from laser irradiation of surfaces. We determined the important role of defects on these emissions, the thermal, chemical, and physical interactions responsible for matrix effects and mass-dependent transport/detection. This work supported development of new techniques and technology for the determination of trace elements contained such as nuclear waste materials.

Dickinson, J. T. [Washington State University] [Washington State University

2014-04-05T23:59:59.000Z

277

Photonic band gap of a graphene-embedded quarter-wave stack  

SciTech Connect (OSTI)

Here, we present a mechanism for tailoring the photonic band structure of a quarter-wave stack without changing its physical periods by embedding conductive sheets. Graphene is utilized and studied as a realistic, two-dimensional conductive sheet. In a graphene-embedded quarter-wave stack, the synergic actions of Bragg scattering and graphene conductance contributions open photonic gaps at the center of the reduced Brillouin zone that are nonexistent in conventional quarter-wave stacks. Such photonic gaps show giant, loss-independent density of optical states at the fixed lower-gap edges, of even-multiple characteristic frequency of the quarter-wave stack. The conductive sheet-induced photonic gaps provide a platform for the enhancement of light-matter interactions.

Fan, Yuancheng [Ames Laboratory; Wei, Zeyong [Tongji University; Li, Hongqiang [Tongji University; Chen, Hong [Tongji University; Soukoulis, Costas M [Ames Laboratory

2013-12-10T23:59:59.000Z

278

Low Band Gap Poly(thienylene vinylene)/Fullerene Bulk Heterojunction Photovoltaic Cells  

Science Journals Connector (OSTI)

This work was funded by the Initiative for Renewable Energy and the Environment (IREE) at the University of Minnesota (UMN) and the Xcel Energy Renewable Development Fund. ...

Jung Yong Kim; Yang Qin; Derek M. Stevens; Ozan Ugurlu; Vivek Kalihari; Marc A. Hillmyer; C. Daniel Frisbie

2009-05-21T23:59:59.000Z

279

Strain-tunable Photonic Band Gap Microcavity Waveguides in Silicon at 1.55 m  

E-Print Network [OSTI]

+ , Sang-Gook Kim+ * Columbia University, New York, NY 10027 + Massachusetts Institute of Technology for reconfiguration of the optical characteristics based on user-demand, but also for compensation against external the Optical Response of Photonic Bandgap Structures, edited by Philippe M. Fauchet, Paul V. Braun, Proceedings

280

Tunable band gap in graphene with a noncentrosymmetric superlattice potential Rakesh P. Tiwari and D. Stroud  

E-Print Network [OSTI]

and a hexagonal Brillouin zone BZ . The Fermi-energy EF of homogeneous, neutral graphene lies at the so A number of workers have investigated the possibility of building graphene electronic circuits without of the low-energy charge carriers is anisotropically renormalized,11 while a corrugated graphene sheet

Stroud, David

Note: This page contains sample records for the topic "band-gap semiconductor oxide" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Development of Low Band Gap Polymers for Roll-to-Roll Coated Polymer Solar Cell Modules  

Science Journals Connector (OSTI)

Organic photovoltaics (OPV) have the potential for low production cost. Additionally, there has been an increase in both efficiency and stability of small-area OPV devices prepared in research laboratories wor...

Eva Bundgaard; Frederik Krebs

2011-01-01T23:59:59.000Z

282

E-Print Network 3.0 - accurate band gaps Sample Search Results  

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

Technological University Collection: Physics 7 Improving the efficiency of bulk heterojunction solar cells Summary: the amount of photons absorbed by the film by decreasing the...

283

Novel wide band gap materials for highly efficient thin film tandem solar cells  

SciTech Connect (OSTI)

Tandem solar cells (TSCs), which use two or more materials to absorb sunlight, have achieved power conversion efficiencies of >25% versus 11-20% for commercialized single junction solar cell modules. The key to widespread commercialization of TSCs is to develop the wide-band, top solar cell that is both cheap to fabricate and has a high open-circuit voltage (i.e. >1V). Previous work in TSCs has generally focused on using expensive processing techniques with slow growth rates resulting in costs that are two orders of magnitude too expensive to be used in conventional solar cell modules. The objective of the PLANT PV proposal was to investigate the feasibility of using Ag(In,Ga)Se2 (AIGS) as the wide-bandgap absorber in the top cell of a thin film tandem solar cell (TSC). Despite being studied by very few in the solar community, AIGS solar cells have achieved one of the highest open-circuit voltages within the chalcogenide material family with a Voc of 949mV when grown with an expensive processing technique (i.e. Molecular Beam Epitaxy). PLANT PV�s goal in Phase I of the DOE SBIR was to 1) develop the chemistry to grow AIGS thin films via solution processing techniques to reduce costs and 2) fabricate new device architectures with high open-circuit voltage to produce full tandem solar cells in Phase II. PLANT PV attempted to translate solution processing chemistries that were successful in producing >12% efficient Cu(In,Ga)Se2 solar cells by replacing copper compounds with silver. The main thrust of the research was to determine if it was possible to make high quality AIGS thin films using solution processing and to fully characterize the materials properties. PLANT PV developed several different types of silver compounds in an attempt to fabricate high quality thin films from solution. We found that silver compounds that were similar to the copper based system did not result in high quality thin films. PLANT PV was able to deposit AIGS thin films using a mixture of solution and physical vapor deposition processing, but these films lacked the p-type doping levels that are required to make decent solar cells. Over the course of the project PLANT PV was able to fabricate efficient CIGS solar cells (8.7%) but could not achieve equivalent performance using AIGS. During the nine-month grant PLANT PV set up a variety of thin film characterization tools (e.g. drive-level capacitance profiling) at the Molecular Foundry, a Department of Energy User Facility, that are now available to both industrial and academic researchers via the grant process. PLANT PV was also able to develop the back end processing of thin film solar cells at Lawrence Berkeley National Labs to achieve 8.7% efficient CIGS solar cells. This processing development will be applied to other types of thin film PV cells at the Lawrence Berkeley National Labs. While PLANT PV was able to study AIGS film growth and optoelectronic properties we concluded that AIGS produced using these methods would have a limited efficiency and would not be commercially feasible. PLANT PV did not apply for the Phase II of this grant.

Brian E. Hardin, Stephen T. Connor, Craig H. Peters

2012-06-11T23:59:59.000Z

284

Optimizing the Q value in three-dimensional metallic photonic band gap crystals  

E-Print Network [OSTI]

, and for improving solar energy collection.12 The complementary inductive metallic patches are also FSS with a low in the transmission are created by removing portions of the metallic rods in a single defect layer. A high quality composed of material with a high dielectric constant in a lower dielec- tric background such as air

Soukoulis, Costas

285

Engineering the electromagnetic vacuum for controlling light with light in a photonic-band-gap microchip  

E-Print Network [OSTI]

laser beams ( 1 W steady-state holding power and 5 nW switching power) through mutual coherent resonant broadened collection of "atoms" situated adjacent to the waveguide channel. The "inverted" atomic system can the PBG, light cannot propagate, leading to some fundamentally new opti- cal phenomena

John, Sajeev

286

Second harmonic generation from direct band gap quantum dots pumped by femtosecond laser pulses  

SciTech Connect (OSTI)

We report on nonlinear optical experiments performed on Cu{sub 2}S quantum dots (QDs) pumped by femtosecond laser pulses. We conduct a theoretical simulation and experiments to determine their second harmonic generation characteristics. Furthermore, we demonstrate that the QDs have a second harmonic generation conversion efficiency of up to 76%. Our studies suggest that these Cu{sub 2}S QDs can be used for solar cells, bioimaging, biosensing, and electric detection.

Liu, Liwei, E-mail: liulw@cust.edu.cn; Wang, Yue; Hu, Siyi; Ren, Yu; Huang, Chen [School of Science, Changchun University of Science and Technology, Changchun, Jilin 130022, People's Republic of China and International Joint Research Center for Nanophotonics and Biophotonics, Changchun University of Science and Technology, Changchun, Jilin 130022 (China)

2014-02-21T23:59:59.000Z

287

Sandia National Labs: PCNSC: Departments: Semiconductor and Optical  

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

Semiconductor & Optical Sciences Semiconductor & Optical Sciences > Semiconductor Material & Device Sciences > Advanced Materials Sciences > Lasers, Optics & Remote Sensing Energy Sciences Small Science Cluster Business Office News Partnering Research Jeff Nelson Jerry A. Simmons Sr. Manager Idabelle Idabelle Courtney Admin. Asst. Departments Semiconductor and Optical Sciences The Semiconductor and Optical Sciences Department oversees the operations of the following departments providing new scientific knowledge that can lead to technology solutions in the areas of: Compound semiconductor optoelectronic materials and devices Chemical science to materials technologies, emphasizing the science and engineering of Metal Organic Chemical Vapor Deposition (MOCVD) Remote sensing and detection of WMD proliferation activities

288

Extracting hot carriers from photoexcited semiconductor nanocrystals  

SciTech Connect (OSTI)

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.

Zhu, Xiaoyang

2014-12-10T23:59:59.000Z

289

Light sources based on semiconductor current filaments  

DOE Patents [OSTI]

The present invention provides a new type of semiconductor light source that can produce a high peak power output and is not injection, e-beam, or optically pumped. The present invention is capable of producing high quality coherent or incoherent optical emission. The present invention is based on current filaments, unlike conventional semiconductor lasers that are based on p-n junctions. The present invention provides a light source formed by an electron-hole plasma inside a current filament. The electron-hole plasma can be several hundred microns in diameter and several centimeters long. A current filament can be initiated optically or with an e-beam, but can be pumped electrically across a large insulating region. A current filament can be produced in high gain photoconductive semiconductor switches. The light source provided by the present invention has a potentially large volume and therefore a potentially large energy per pulse or peak power available from a single (coherent) semiconductor laser. Like other semiconductor lasers, these light sources will emit radiation at the wavelength near the bandgap energy (for GaAs 875 nm or near infra red). Immediate potential applications of the present invention include high energy, short pulse, compact, low cost lasers and other incoherent light sources.

Zutavern, Fred J. (Albuquerque, NM); Loubriel, Guillermo M. (Albuquerque, NM); Buttram, Malcolm T. (Sandia Park, NM); Mar, Alan (Albuquerque, NM); Helgeson, Wesley D. (Albuquerque, NM); O'Malley, Martin W. (Edgewood, NM); Hjalmarson, Harold P. (Albuquerque, NM); Baca, Albert G. (Albuquerque, NM); Chow, Weng W. (Cedar Crest, NM); Vawter, G. Allen (Albuquerque, NM)

2003-01-01T23:59:59.000Z

290

Studies on transparent spinel magnesium indium oxide thin films prepared by chemical spray pyrolysis  

Science Journals Connector (OSTI)

Ternary semiconducting oxide compound magnesium indium oxide films (MgIn2O4), manifesting high transparency were prepared by metal organic chemical spray pyrolysis technique. Precursors prepared for various cationic ratios of Mg/In = 0.35, 0.40, 0.45 and 0.50 were thermally sprayed onto quartz substrates, decomposed at 450 °C and the spinel phase evolution was studied. X-ray diffraction, Rutherford backscattering and X-ray photoelectron spectroscopy studies have been conducted to confirm the formation of single-phase MgIn2O4 films with Mg/In ratio 0.50. From optical transmission studies, the observed optical band gaps varied from 3.18 to 3.86 eV (0.35 < Mg/In < 0.5). The electrical conductivity variations of these films were measured in the temperature range between 30 and 150 °C by four-probe technique (34.07–1.44 × 10? 5 S cm? 1) and the Hall coefficient showed n-type electrical conduction and high carrier concentration (0.16 × 1020–0.89 × 17 cm? 3).

A. Moses Ezhil Raj; V. Senthilkumar; V. Swaminathan; Joachim Wollschläger; M. Suendorf; M. Neumann; M. Jayachandran; C. Sanjeeviraja

2008-01-01T23:59:59.000Z

291

Zecon Solar Semiconductor Inc | Open Energy Information  

Open Energy Info (EERE)

Zecon Solar Semiconductor Inc Zecon Solar Semiconductor Inc Jump to: navigation, search Name Zecon Solar & Semiconductor Inc Place Cupertino, California Zip 95014 Sector Solar Product Focused on large-scale solar building integrated PV systems. Coordinates 37.31884°, -122.029244° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":37.31884,"lon":-122.029244,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

292

Two-Photon Emission from Semiconductors  

E-Print Network [OSTI]

We report the first experimental observations of two-photon emission from semiconductors, to the best of our knowledge, and develop a corresponding theory for the room-temperature process. Spontaneous two-photon emission is demonstrated in optically-pumped bulk GaAs and in electrically-driven GaInP/AlGaInP quantum wells. Singly-stimulated two-photon emission measurements demonstrate the theoretically predicted two-photon optical gain in semiconductors - a necessary ingredient for any realizations of future two-photon semiconductor lasers. Photon-coincidence experiment validates the simultaneity of the electrically-driven GaInP/AlGaInP two-photon emission, limited only by detector's temporal resolution.

Alex Hayat; Pavel Ginzburg; Meir Orenstein

2007-10-25T23:59:59.000Z

293

Substrate solder barriers for semiconductor epilayer growth  

DOE Patents [OSTI]

During the growth of compound semiconductors by epitaxial processes, substrates are typically mounted to a support. In modular beam epitaxy, mounting is done using indium as a solder. This method has two drawbacks: the indium reacts with the substrate, and it is difficult to uniformly wet the back of a large diameter substrate. Both of these problems have been successfully overcome by sputter coating the back of the substrate with a thin layer of tungsten carbide or tungsten carbide and gold. In addition to being compatible with the growth of high quality semiconductor epilayers this coating is also inert in all standard substrate cleaning etchants used for compound semiconductors, and provides uniform distribution of energy in radiant heating.

Drummond, T.J.; Ginley, D.S.; Zipperian, T.E.

1989-05-09T23:59:59.000Z

294

Substrate solder barriers for semiconductor epilayer growth  

DOE Patents [OSTI]

During the growth of compound semiconductors by epitaxial processes, substrates are typically mounted to a support. In molecular beam epitaxy, mounting is done using indium as a solder. This method has two drawbacks: the indium reacts with the substrate, and it is difficult to uniformly wet the back of a large diameter substrate. Both of these problems have been successfully overcome by sputter coating the back of the substrate with a thin layer of tungsten carbide or tungsten carbide and gold. In addition to being compatible with the growth of high quality semiconductor epilayers this coating is also inert in all standard substate cleaning etchants used for compound semiconductors, and provides uniform distribution of energy in radiant heating. 1 tab.

Drummond, T.J.; Ginley, D.S.; Zipperian, T.E.

1987-10-23T23:59:59.000Z

295

Emissivity Correcting Pyrometry of Semiconductor Growth  

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

Emissivity Correcting Pyrometry of Semiconductor Growth Emissivity Correcting Pyrometry of Semiconductor Growth by W. G. Breiland, L. A. Bruskas, A. A. Allerman, and T. W. Hargett Motivation-Temperature is a critical factor in the growth of thin films by either chemical vapor deposition (CVD) or molecular beam epitaxy (MBE). It is particularly important in compound semiconductor growth because one is often challenged to grow materials with specific chemical compositions in order to maintain stringent lattice-matching conditions or to achieve specified bandgap values. Optical pyrometry can be used to measure surface temperatures, but the thin film growth causes significant changes in the emissivity of the surface, leading to severe errors in the pyrometer measurement. To avoid these errors, emissivity changes must be measured and

296

Charged steps on III-V compound semiconductor surfaces  

Science Journals Connector (OSTI)

The electrical charge of steps on (110) surfaces of InP, GaP, and GaAs is probed by scanning tunneling microscopy. It is demonstrated that step edges, with and without kinks, are charged and have localized defect states in the band gap. The charge of indium-terminated step edges on p-type doped InP(110) after annealing is found to be independent of the step orientation, while a strong orientation dependence is observed for phosphorus-terminated steps. This is explained by a partial compensation of the charge due to rebonding after phosphorus desorption. The magnitude of charge is estimated to be in the range of +1e to +3e per lattice spacing. © 1996 The American Physical Society.

M. Heinrich, C. Domke, Ph. Ebert, and K. Urban

1996-04-15T23:59:59.000Z

297

Semiconductor Equipment and Materials International SEMI | Open Energy  

Open Energy Info (EERE)

Semiconductor Equipment and Materials International SEMI Semiconductor Equipment and Materials International SEMI Jump to: navigation, search Name Semiconductor Equipment and Materials International (SEMI) Place San Jose, California Zip 95134 2127 Product Global trade association, publisher and conference organiser representing the semiconductor and flat panel display equipment manufacturers. References Semiconductor Equipment and Materials International (SEMI)[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Semiconductor Equipment and Materials International (SEMI) is a company located in San Jose, California . References ↑ "Semiconductor Equipment and Materials International (SEMI)" Retrieved from "http://en.openei.org/w/index.php?title=Semiconductor_Equipment_and_Materials_International_SEMI&oldid=350739

298

A New Cleanroom for a Next-Generation Semiconductor Research...  

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

A New Cleanroom for a Next-Generation Semiconductor Research Tool A New Cleanroom for a Next-Generation Semiconductor Research Tool Print The new Sector 12 cleanroom under...

299

Silicon Carbide Power Semiconductor Devices in the Cleanroom...  

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

Silicon Carbide Power Semiconductor Devices in the Cleanroom Silicon Carbide Power Semiconductor Devices in the Cleanroom Ron Olson 2012.10.04 I would like to introduce Zach Stum,...

300

DECENTRALIZING SEMICONDUCTOR CAPACITY PLANNING VIA INTERNAL MARKET COORDINATION  

E-Print Network [OSTI]

1 DECENTRALIZING SEMICONDUCTOR CAPACITY PLANNING VIA INTERNAL MARKET COORDINATION SULEYMAN KARABUK semiconductor manufacturer: marketing managers reserve capacity from manufacturing based on product demands, while attempting to maximize profit; manufacturing managers allocate capacity to competing marketing

Wu, David

Note: This page contains sample records for the topic "band-gap semiconductor oxide" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

APPLIED PHYSICS REVIEWS Semi-insulating semiconductor heterostructures: Optoelectronic  

E-Print Network [OSTI]

APPLIED PHYSICS REVIEWS Semi-insulating semiconductor heterostructures: Optoelectronic properties of optoelectronic properties of and uses for semi-insulating semiconductor heterostructures and thin films. The principal optical and optoelectronic properties of semi-insulating epilayers and heterostructures

Nolte, David D.

302

Taiwan Semiconductor Manufacturing Co Ltd TSMC | Open Energy Information  

Open Energy Info (EERE)

Semiconductor Manufacturing Co Ltd TSMC Semiconductor Manufacturing Co Ltd TSMC Jump to: navigation, search Name Taiwan Semiconductor Manufacturing Co Ltd (TSMC) Place Hsinchu, Taiwan Zip 300 Sector Solar Product Taiwan-based semiconductor company. The firm is also venturing into solar and LED production. References Taiwan Semiconductor Manufacturing Co Ltd (TSMC)[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Taiwan Semiconductor Manufacturing Co Ltd (TSMC) is a company located in Hsinchu, Taiwan . References ↑ "Taiwan Semiconductor Manufacturing Co Ltd (TSMC)" Retrieved from "http://en.openei.org/w/index.php?title=Taiwan_Semiconductor_Manufacturing_Co_Ltd_TSMC&oldid=352012"

303

Method Of Transferring A Thin Crystalline Semiconductor Layer  

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

Method Of Transferring A Thin Crystalline Semiconductor Layer Method Of Transferring A Thin Crystalline Semiconductor Layer Method Of Transferring A Thin Crystalline Semiconductor Layer A method for transferring a thin semiconductor layer from one substrate to another substrate involves depositing a thin epitaxial monocrystalline semiconductor layer on a substrate having surface contaminants. Available for thumbnail of Feynman Center (505) 665-9090 Email Method Of Transferring A Thin Crystalline Semiconductor Layer A method for transferring a thin semiconductor layer from one substrate to another substrate involves depositing a thin epitaxial monocrystalline semiconductor layer on a substrate having surface contaminants. An interface that includes the contaminants is formed in between the deposited layer and the substrate. Hydrogen atoms are introduced into the structure

304

Moessbauer studies of two-electron centers with negative correlation energy in crystalline and amorphous semiconductors  

SciTech Connect (OSTI)

The results of the study of donor U{sup -}-centers of tin and germanium in lead chalcogenides by Moessbauer emission spectroscopy are discussed. The published data regarding the identification of amphoteric U{sup -}-centers of tin in glassy binary arsenic and germanium chalcogenides using Moessbauer emission spectroscopy, and in multicomponent chalcogenide glasses using Moessbauer absorption spectroscopy are considered. Published data concerning the identification of two-atom U{sup -}-centers of copper in lattices of semimetal copper oxides by Moessbauer emission spectroscopy are analyzed. The published data on the detection of spatial inhomogeneity of the Bose-Einstein condensate in superconducting semiconductors and semimetal compounds, and on the existence of the correlation between the electron density in lattice sites and the superconducting transition temperature are presented. The principal possibility of using Moessbauer U{sup -}-centers as a tool for studying the Bose-Einstein condensation of electron pairs during the superconducting phase transition in semiconductors and semimetals is considered.

Bordovsky, G. A. [Alexander Herzen State Pedagogical University of Russia (Russian Federation); Nemov, S. A. [St Petersburg State Polytechnical University (Russian Federation); Marchenko, A. V.; Seregin, P. P., E-mail: ppseregin@mail.ru [Alexander Herzen State Pedagogical University of Russia (Russian Federation)

2012-01-15T23:59:59.000Z

305

Structural and magnetic characterization of norbornenedeuterated norbornene dicarboxylic acid diblock copolymers doped with iron oxide  

E-Print Network [OSTI]

, Ag, Pd, Pt, Cu) [5­9] and semiconductor nanoclusters (PbS, CdS, ZnS) [10­12] were synthesized within diblock copolymers doped with iron oxide nanoparticles Pinar Akcoraa , Xin Zhangb , Bindhu Varughesec 2005 Available online 29 April 2005 Abstract A series of iron oxide doped norbornene (NOR

Rubloff, Gary W.

306

Porous Diblock Copolymer Thin Films in High-Performance Semiconductor Microelectronics  

SciTech Connect (OSTI)

The engine fueling more than 40 years of performance improvements in semiconductor integrated circuits (ICs) has been industry's ability to pattern circuit elements at ever-higher resolution and with ever-greater precision. Steady advances in photolithography - the process wherein ultraviolet light chemically changes a photosensitive polymer resist material in order to create a latent image - have resulted in scaling of minimum printed feature sizes from tens of microns during the 1980s to sub-50 nanometer transistor gate lengths in today's state-of-the-art ICs. The history of semiconductor technology scaling as well as future technology requirements is documented in the International Technology Roadmap for Semiconductors (ITRS). The progression of the semiconductor industry to the realm of nanometer-scale sizes has brought enormous challenges to device and circuit fabrication, rendering performance improvements by conventional scaling alone increasingly difficult. Most often this discussion is couched in terms of field effect transistor (FET) feature sizes such as the gate length or gate oxide thickness, however these challenges extend to many other aspects of the IC, including interconnect dimensions and pitch, device packing density, power consumption, and heat dissipation. The ITRS Technology Roadmap forecasts a difficult set of scientific and engineering challenges with no presently-known solutions. The primary focus of this chapter is the research performed at IBM on diblock copolymer films composed of polystyrene (PS) and poly(methyl-methacrylate) (PMMA) (PS-b-PMMA) with total molecular weights M{sub n} in the range of {approx}60K (g/mol) and polydispersities (PD) of {approx}1.1. These materials self assemble to form patterns having feature sizes in the range of 15-20nm. PS-b-PMMA was selected as a self-assembling patterning material due to its compatibility with the semiconductor microelectronics manufacturing infrastructure, as well as the significant body of existing research on understanding its material properties.

Black, C.T.

2011-02-01T23:59:59.000Z

307

Semiconductor nanowires DOI: 10.1002/smll.200500094  

E-Print Network [OSTI]

of a semiconductor Si nanowire, synthesized via the VLS pro- cess, into metallic nickel silicide through parameters. Anisotropic growth of a metal onto a semiconductor nanowire (or a semicon- ductor on a metal approach to prepare metal/semiconductor nano- wire heterostructures by transforming specific sections

Rogers, John A.

308

High-Frequency Conductivity of Degenerate Semiconductors  

Science Journals Connector (OSTI)

The problem of high-frequency conductivity of a degenerate semiconductor is investigated by a kinetic description. The finite duration of encounters is taken into account in a self-consistent fashion which properly includes collective effects. This treatment is an extension for quantum plasmas of the Dawson-Oberman method given for classical plasmas.

Amiram Ron and Narkis Tzoar

1963-09-01T23:59:59.000Z

309

Semiconductor Nanowire Optical Antenna Solar Absorbers  

E-Print Network [OSTI]

technology. KEYWORDS Solar cell, semiconductor nanowires, optical antennas, photon management, light trapping a clear, intuitive guidance for the design of efficient NW solar cells. The presented approach to exhibit a strongly angle-dependent optical response and the resulting solar cells require bulky solar

Fan, Shanhui

310

Semiconductor detectors with proximity signal readout  

SciTech Connect (OSTI)

Semiconductor-based radiation detectors are routinely used for the detection, imaging, and spectroscopy of x-rays, gamma rays, and charged particles for applications in the areas of nuclear and medical physics, astrophysics, environmental remediation, nuclear nonproliferation, and homeland security. Detectors used for imaging and particle tracking are more complex in that they typically must also measure the location of the radiation interaction in addition to the deposited energy. In such detectors, the position measurement is often achieved by dividing or segmenting the electrodes into many strips or pixels and then reading out the signals from all of the electrode segments. Fine electrode segmentation is problematic for many of the standard semiconductor detector technologies. Clearly there is a need for a semiconductor-based radiation detector technology that can achieve fine position resolution while maintaining the excellent energy resolution intrinsic to semiconductor detectors, can be fabricated through simple processes, does not require complex electrical interconnections to the detector, and can reduce the number of required channels of readout electronics. Proximity electrode signal readout (PESR), in which the electrodes are not in physical contact with the detector surface, satisfies this need.

Asztalos, Stephen J. [XIA, LLC, Hayward, CA (United States)

2014-01-30T23:59:59.000Z

311

Organic conductive films for semiconductor electrodes  

DOE Patents [OSTI]

According to the present invention, improved electrodes overcoated with conductive polymer films and preselected catalysts are provided. The electrodes typically comprise an inorganic semiconductor over-coated with a charge conductive polymer film comprising a charge conductive polymer in or on which is a catalyst or charge-relaying agent.

Frank, A.J.

1984-01-01T23:59:59.000Z

312

Defect Tolerant Semiconductors for Solar Energy Conversion  

Science Journals Connector (OSTI)

Defect Tolerant Semiconductors for Solar Energy Conversion ... He obtained his Ph.D. in Physics at Paris-Sud University where he modeled Hot Carrier Solar Cells by means of Ensemble Monte Carlo methods. ... These surface energies are significantly lower compared to 96 and 102 meV/Å2 for (1010) and (1120) low energy nonpolar GaN surfaces respectively. ...

Andriy Zakutayev; Christopher M. Caskey; Angela N. Fioretti; David S. Ginley; Julien Vidal; Vladan Stevanovic; Eric Tea; Stephan Lany

2014-03-13T23:59:59.000Z

313

HYDROGEN LOCAL VIBRATIONAL MODES IN COMPOUND SEMICONDUCTORS  

E-Print Network [OSTI]

HYDROGEN LOCAL VIBRATIONAL MODES IN COMPOUND SEMICONDUCTORS M.D. MCCLUSKEY* University) spectroscopy of hydrogen and deuterium in GaP, AlSb, ZnSe, and GaN has provided important information about the structures of dopant- hydrogen complexes and their interaction with the host lattice. In GaN:Mg, for example

McCluskey, Matthew

314

Optical temperature sensor using thermochromic semiconductors  

DOE Patents [OSTI]

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.

Kronberg, J.W.

1994-01-01T23:59:59.000Z

315

High resolution scintillation detector with semiconductor readout  

DOE Patents [OSTI]

A novel high resolution scintillation detector array for use in radiation imaging such as high resolution Positron Emission Tomography (PET) which comprises one or more parallelepiped crystals with at least one long surface of each crystal being in intimate contact with a semiconductor photodetector such that photons generated within each crystal by gamma radiation passing therethrough is detected by the photodetector paired therewith.

Levin, Craig S. (Santa Monica, CA); Hoffman, Edward J. (Los Angeles, CA)

2000-01-01T23:59:59.000Z

316

Metal Oxides  

Science Journals Connector (OSTI)

Metal oxides are the class of materials having the widest application in gas sensors. This chapter presents information related to the application of various metal oxides in gas sensors designed on different p...

Ghenadii Korotcenkov

2013-01-01T23:59:59.000Z

317

A Spintronic Semiconductor with Selectable Charge Carriers  

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

A Spintronic Semiconductor with Selectable Charge Carriers Print A Spintronic Semiconductor with Selectable Charge Carriers Print Accentuating the Positive (or the Negative) Spintronics-a type of electronics that makes use of electron spin as well as charge-is already here to a certain extent. The discovery of giant magnetoresistance, a spin-based effect, has revolutionized the information storage industry. Beyond this, however, scientists envision the possibility of combining storage and processing functions in one integrated system. In electronics, processing is done using semiconductor materials like silicon and germanium that have the requisite properties to perform logical operations with both electrons (negative n-type charge carriers) and holes (positive p-type charge carriers). Thus, a spintronically desirable semiconductor would simultaneously have discrete spin-up and spin-down states as well as both positive and negative charge carriers. Strategies for developing spintronic semiconductors have been based on surface doping or on alloying, both of which have drawbacks such as chemical instability or reduced mobility. In BiTeI, however, electron and hole conduction is achieved without modifying the ideal crystal structure. One of the things discovered by Crepaldi et al. was that the electronic band structure of BiTeI bends in different ways near the surface depending on which layer is on top. That, in turn, means that the Fermi level (which determines a material's conductivity) can be located in either the valence band (for positive charge carriers) or the conduction band (for negative charge carriers). With techniques such as molecular-beam epitaxy and chemical vapor deposition, it is realistic to consider that regions with opposite band bending could be patterned on a substrate, opening new possibilities for the manipulation of spin-polarized states.

318

A Spintronic Semiconductor with Selectable Charge Carriers  

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

A Spintronic Semiconductor with Selectable Charge Carriers Print A Spintronic Semiconductor with Selectable Charge Carriers Print Accentuating the Positive (or the Negative) Spintronics-a type of electronics that makes use of electron spin as well as charge-is already here to a certain extent. The discovery of giant magnetoresistance, a spin-based effect, has revolutionized the information storage industry. Beyond this, however, scientists envision the possibility of combining storage and processing functions in one integrated system. In electronics, processing is done using semiconductor materials like silicon and germanium that have the requisite properties to perform logical operations with both electrons (negative n-type charge carriers) and holes (positive p-type charge carriers). Thus, a spintronically desirable semiconductor would simultaneously have discrete spin-up and spin-down states as well as both positive and negative charge carriers. Strategies for developing spintronic semiconductors have been based on surface doping or on alloying, both of which have drawbacks such as chemical instability or reduced mobility. In BiTeI, however, electron and hole conduction is achieved without modifying the ideal crystal structure. One of the things discovered by Crepaldi et al. was that the electronic band structure of BiTeI bends in different ways near the surface depending on which layer is on top. That, in turn, means that the Fermi level (which determines a material's conductivity) can be located in either the valence band (for positive charge carriers) or the conduction band (for negative charge carriers). With techniques such as molecular-beam epitaxy and chemical vapor deposition, it is realistic to consider that regions with opposite band bending could be patterned on a substrate, opening new possibilities for the manipulation of spin-polarized states.

319

A Spintronic Semiconductor with Selectable Charge Carriers  

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

A Spintronic Semiconductor with Selectable Charge Carriers Print A Spintronic Semiconductor with Selectable Charge Carriers Print Accentuating the Positive (or the Negative) Spintronics-a type of electronics that makes use of electron spin as well as charge-is already here to a certain extent. The discovery of giant magnetoresistance, a spin-based effect, has revolutionized the information storage industry. Beyond this, however, scientists envision the possibility of combining storage and processing functions in one integrated system. In electronics, processing is done using semiconductor materials like silicon and germanium that have the requisite properties to perform logical operations with both electrons (negative n-type charge carriers) and holes (positive p-type charge carriers). Thus, a spintronically desirable semiconductor would simultaneously have discrete spin-up and spin-down states as well as both positive and negative charge carriers. Strategies for developing spintronic semiconductors have been based on surface doping or on alloying, both of which have drawbacks such as chemical instability or reduced mobility. In BiTeI, however, electron and hole conduction is achieved without modifying the ideal crystal structure. One of the things discovered by Crepaldi et al. was that the electronic band structure of BiTeI bends in different ways near the surface depending on which layer is on top. That, in turn, means that the Fermi level (which determines a material's conductivity) can be located in either the valence band (for positive charge carriers) or the conduction band (for negative charge carriers). With techniques such as molecular-beam epitaxy and chemical vapor deposition, it is realistic to consider that regions with opposite band bending could be patterned on a substrate, opening new possibilities for the manipulation of spin-polarized states.

320

A Spintronic Semiconductor with Selectable Charge Carriers  

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

A Spintronic Semiconductor with Selectable Charge Carriers Print A Spintronic Semiconductor with Selectable Charge Carriers Print Accentuating the Positive (or the Negative) Spintronics-a type of electronics that makes use of electron spin as well as charge-is already here to a certain extent. The discovery of giant magnetoresistance, a spin-based effect, has revolutionized the information storage industry. Beyond this, however, scientists envision the possibility of combining storage and processing functions in one integrated system. In electronics, processing is done using semiconductor materials like silicon and germanium that have the requisite properties to perform logical operations with both electrons (negative n-type charge carriers) and holes (positive p-type charge carriers). Thus, a spintronically desirable semiconductor would simultaneously have discrete spin-up and spin-down states as well as both positive and negative charge carriers. Strategies for developing spintronic semiconductors have been based on surface doping or on alloying, both of which have drawbacks such as chemical instability or reduced mobility. In BiTeI, however, electron and hole conduction is achieved without modifying the ideal crystal structure. One of the things discovered by Crepaldi et al. was that the electronic band structure of BiTeI bends in different ways near the surface depending on which layer is on top. That, in turn, means that the Fermi level (which determines a material's conductivity) can be located in either the valence band (for positive charge carriers) or the conduction band (for negative charge carriers). With techniques such as molecular-beam epitaxy and chemical vapor deposition, it is realistic to consider that regions with opposite band bending could be patterned on a substrate, opening new possibilities for the manipulation of spin-polarized states.

Note: This page contains sample records for the topic "band-gap semiconductor oxide" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

A Spintronic Semiconductor with Selectable Charge Carriers  

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

A Spintronic Semiconductor with Selectable Charge Carriers Print A Spintronic Semiconductor with Selectable Charge Carriers Print Accentuating the Positive (or the Negative) Spintronics-a type of electronics that makes use of electron spin as well as charge-is already here to a certain extent. The discovery of giant magnetoresistance, a spin-based effect, has revolutionized the information storage industry. Beyond this, however, scientists envision the possibility of combining storage and processing functions in one integrated system. In electronics, processing is done using semiconductor materials like silicon and germanium that have the requisite properties to perform logical operations with both electrons (negative n-type charge carriers) and holes (positive p-type charge carriers). Thus, a spintronically desirable semiconductor would simultaneously have discrete spin-up and spin-down states as well as both positive and negative charge carriers. Strategies for developing spintronic semiconductors have been based on surface doping or on alloying, both of which have drawbacks such as chemical instability or reduced mobility. In BiTeI, however, electron and hole conduction is achieved without modifying the ideal crystal structure. One of the things discovered by Crepaldi et al. was that the electronic band structure of BiTeI bends in different ways near the surface depending on which layer is on top. That, in turn, means that the Fermi level (which determines a material's conductivity) can be located in either the valence band (for positive charge carriers) or the conduction band (for negative charge carriers). With techniques such as molecular-beam epitaxy and chemical vapor deposition, it is realistic to consider that regions with opposite band bending could be patterned on a substrate, opening new possibilities for the manipulation of spin-polarized states.

322

A Spintronic Semiconductor with Selectable Charge Carriers  

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

A Spintronic Semiconductor with Selectable Charge Carriers Print A Spintronic Semiconductor with Selectable Charge Carriers Print Accentuating the Positive (or the Negative) Spintronics-a type of electronics that makes use of electron spin as well as charge-is already here to a certain extent. The discovery of giant magnetoresistance, a spin-based effect, has revolutionized the information storage industry. Beyond this, however, scientists envision the possibility of combining storage and processing functions in one integrated system. In electronics, processing is done using semiconductor materials like silicon and germanium that have the requisite properties to perform logical operations with both electrons (negative n-type charge carriers) and holes (positive p-type charge carriers). Thus, a spintronically desirable semiconductor would simultaneously have discrete spin-up and spin-down states as well as both positive and negative charge carriers. Strategies for developing spintronic semiconductors have been based on surface doping or on alloying, both of which have drawbacks such as chemical instability or reduced mobility. In BiTeI, however, electron and hole conduction is achieved without modifying the ideal crystal structure. One of the things discovered by Crepaldi et al. was that the electronic band structure of BiTeI bends in different ways near the surface depending on which layer is on top. That, in turn, means that the Fermi level (which determines a material's conductivity) can be located in either the valence band (for positive charge carriers) or the conduction band (for negative charge carriers). With techniques such as molecular-beam epitaxy and chemical vapor deposition, it is realistic to consider that regions with opposite band bending could be patterned on a substrate, opening new possibilities for the manipulation of spin-polarized states.

323

Chemical Bonding, Interfaces and Defects in Hafnium Oxide/Germanium Oxynitride Gate Stacks on Ge (100)  

SciTech Connect (OSTI)

Correlations among interface properties and chemical bonding characteristics in HfO{sub 2}/GeO{sub x}N{sub y}/Ge MIS stacks were investigated using in-situ remote nitridation of the Ge (100) surface prior to HfO{sub 2} atomic layer deposition (ALD). Ultra thin ({approx}1.1 nm), thermally stable and aqueous etch-resistant GeO{sub x}N{sub y} interfaces layers that exhibited Ge core level photoelectron spectra (PES) similar to stoichiometric Ge{sub 3}N{sub 4} were synthesized. To evaluate GeO{sub x}N{sub y}/Ge interface defects, the density of interface states (D{sub it}) was extracted by the conductance method across the band gap. Forming gas annealed (FGA) samples exhibited substantially lower D{sub it} ({approx} 1 x 10{sup 12} cm{sup -2} eV{sup -1}) than did high vacuum annealed (HVA) and inert gas anneal (IGA) samples ({approx} 1x 10{sup 13} cm{sup -2} eV{sup -1}). Germanium core level photoelectron spectra from similar FGA-treated samples detected out-diffusion of germanium oxide to the HfO{sub 2} film surface and apparent modification of chemical bonding at the GeO{sub x}N{sub y}/Ge interface, which is related to the reduced D{sub it}.

Oshima, Yasuhiro; /Stanford U., Materials Sci. Dept.; Sun, Yun; /SLAC, SSRL; Kuzum, Duygu; /Stanford U.; Sugawara, Takuya; Saraswat, Krishna C.; Pianetta, Piero; /SLAC, SSRL; McIntyre, Paul C.; /Stanford U., Materials Sci. Dept.

2008-10-31T23:59:59.000Z

324

Novel synthesis of hafnium oxide nanoparticles by precipitation method and its characterization  

SciTech Connect (OSTI)

Highlights: ? HfO{sub 2} NPs were prepared by precipitation method. ? XRD and Raman analysis revealed the presence of monoclinic phase. ? The average particle size of HfO{sub 2} NPs is 20 nm. ? The method is a simple, low cost and eco-friendly approach. -- Abstract: Hafnium oxide nanoparticles (HfO{sub 2} NPs) have been successfully synthesized by means of a novel precipitation method and were characterized by using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Field emission scanning electron microscopy (FESEM), UV–visible, Fourier transform infrared (FTIR) and laser Raman spectroscopy. The XRD and Raman analysis revealed the presence of pure monoclinic HfO{sub 2} NPs. FESEM image showed that the HfO{sub 2} NPs were of spherical shape with an average particle size of about 20 nm. The optical band gap of the HfO{sub 2} NPs was found to be 6.12 eV. Advantages of this method were simple and low cost of synthesis of HfO{sub 2} NPs includes the small and narrow particle size distribution.

Ramadoss, Ananthakumar; Krishnamoorthy, Karthikeyan [Nanomaterials and System Lab, Department of Mechanical System Engineering, Jeju National University, Jeju 690-756 (Korea, Republic of)] [Nanomaterials and System Lab, Department of Mechanical System Engineering, Jeju National University, Jeju 690-756 (Korea, Republic of); Kim, Sang Jae, E-mail: kimsangj@jejunu.ac.kr [Nanomaterials and System Lab, Department of Mechanical System Engineering, Jeju National University, Jeju 690-756 (Korea, Republic of); Department of Mechatronics Engineering, Jeju National University, Jeju 690-756 (Korea, Republic of)

2012-09-15T23:59:59.000Z

325

Structural, Morphological and Optical properties of Sputtered Nickel oxide Thin Films  

SciTech Connect (OSTI)

Nickel oxide (NiO) thin films have been deposited by dc reactive magnetron sputtering technique on glass substrates at various substrate temperatures in the range of 303 to 723 K. The influence of substrate temperature on structural, morphological, compositional and optical properties was analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), energy dispersive spectroscopy (EDS) and spectrophotometer studies. The structural properties of the films were strongly influenced by the substrate temperature. From the microstructural studies, fine and uniform grains were grown with RMS roughness of 9.4 nm at substrate temperature of 523 K. The optical results indicated that the optical transmittance of the films increases with increasing substrate temperature up to 523 K, thereafter decreases. The optical band of the films increases with substrate temperature initially, thereafter decreased at higher temperatures. The Highest optical transmittance of 60 % and optical band gap of 3.82 eV was observed in the present study.

Reddy, A. Mallikarjuna; Reddy, A. Sivasankar; Reddy, P. Sreedhara [Department of Physics, Sri Venkateswara University, Tirupati-517 502 (India)

2011-10-20T23:59:59.000Z

326

Semiconductor P-I-N detector  

DOE Patents [OSTI]

A semiconductor P-I-N detector including an intrinsic wafer, a P-doped layer, an N-doped layer, and a boundary layer for reducing the diffusion of dopants into the intrinsic wafer. The boundary layer is positioned between one of the doped regions and the intrinsic wafer. The intrinsic wafer can be composed of CdZnTe or CdTe, the P-doped layer can be composed of ZnTe doped with copper, and the N-doped layer can be composed of CdS doped with indium. The boundary layers is formed of an undoped semiconductor material. The boundary layer can be deposited onto the underlying intrinsic wafer. The doped regions are then typically formed by a deposition process or by doping a section of the deposited boundary layer.

Sudharsanan, Rengarajan (53 Timber Line Dr., Nashua, NH 03062); Karam, Nasser H. (577 Lowell St., Lexington, MA 02173)

2001-01-01T23:59:59.000Z

327

Method of transferring strained semiconductor structure  

DOE Patents [OSTI]

The transfer of strained semiconductor layers from one substrate to another substrate involves depositing a multilayer structure on a substrate having surface contaminants. An interface that includes the contaminants is formed in between the deposited layer and the substrate. Hydrogen atoms are introduced into the structure and allowed to diffuse to the interface. Afterward, the deposited multilayer structure is bonded to a second substrate and is separated away at the interface, which results in transferring a multilayer structure from one substrate to the other substrate. The multilayer structure includes at least one strained semiconductor layer and at least one strain-induced seed layer. The strain-induced seed layer can be optionally etched away after the layer transfer.

Nastasi, Michael A. (Santa Fe, NM); Shao, Lin (College Station, TX)

2009-12-29T23:59:59.000Z

328

"Magnetically dead" surface layers on ferromagnetic semiconductors  

Science Journals Connector (OSTI)

We perform an exact model calculation for the conduction-band spin structure of ferromagnetic semiconductors. The purpose of this illustrative quasiatomic theory (which is an abstraction of our earlier general theory) is to demonstrate that the case T=0 (i.e., ferromagnetic saturation) exhibits vanishingly small spectral weights of certain quasiparticle or scattering states which, however, become manifest for T>0, and determine the electron-spin polarization. Hence T=0 results cannot be generalized to nonzero temperatures and should not be used to prove or disprove the existence of "magnetically dead" surface layers on ferromagnetic semiconductors. The existence of such dead layers has frequently been postulated to explain the electron-spin polarization in photoemission and field-emission experiments.

W. Nolting and B. Reihl

1983-10-01T23:59:59.000Z

329

Optical cavity furnace for semiconductor wafer processing  

DOE Patents [OSTI]

An optical cavity furnace 10 having multiple optical energy sources 12 associated with an optical cavity 18 of the furnace. The multiple optical energy sources 12 may be lamps or other devices suitable for producing an appropriate level of optical energy. The optical cavity furnace 10 may also include one or more reflectors 14 and one or more walls 16 associated with the optical energy sources 12 such that the reflectors 14 and walls 16 define the optical cavity 18. The walls 16 may have any desired configuration or shape to enhance operation of the furnace as an optical cavity 18. The optical energy sources 12 may be positioned at any location with respect to the reflectors 14 and walls defining the optical cavity. The optical cavity furnace 10 may further include a semiconductor wafer transport system 22 for transporting one or more semiconductor wafers 20 through the optical cavity.

Sopori, Bhushan L.

2014-08-05T23:59:59.000Z

330

Semiconductor Manufacturing International Corp SMIC | Open Energy  

Open Energy Info (EERE)

Manufacturing International Corp SMIC Manufacturing International Corp SMIC Jump to: navigation, search Name Semiconductor Manufacturing International Corp (SMIC) Place Shanghai, Shanghai Municipality, China Zip 201203 Sector Solar Product Semiconductor group launching solar cell production from its recycled silicon wafers. Coordinates 31.247709°, 121.472618° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":31.247709,"lon":121.472618,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

331

A Markovian analysis of semiconductor manufacturing processes  

E-Print Network [OSTI]

) Karan L. Watson (Member) Martin A. Wortman (Member) ep Sastri (Member) o W. Howze (Head of Department) December 1991 ABSTRACT A Markovian Analysis of Semiconductor Manufacturing Processes. (December 1991) Kent Eugene Schultz, B. S. , Iowa... grateful to Dr. Martin Wortman, for his pa- tience and endless stream of examples to help me understand stochastic processes. I would also like to thank Dr. Tep Sastri for his patience and for always having a refer- ence available when I needed it...

Schultz, Kent Eugene

2012-06-07T23:59:59.000Z

332

Electrical Usage Characterization of Semiconductor Processing Tools  

E-Print Network [OSTI]

ELECTRICAL USAGE CHARACTERIZATION OF SEMICONDUCTOR PROCESSING TOOLS Scott R. Hinson Associate Engineer Radian Electronic Systems 15705 Long Vista Drive Austin, TX 78751 Abstract This paper presents the basic concepts in performing... be completed using as much detail as possible. The most often cited reason for aUditing process tools is the large discrepancy between the facilities requirements listed on the tool nameplate and the actual measured usage. I have measured systems...

Hinson, S. R.

333

GaTe semiconductor for radiation detection  

DOE Patents [OSTI]

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.

Payne, Stephen A. (Castro Valley, CA); Burger, Arnold (Nashville, TN); Mandal, Krishna C. (Ashland, MA)

2009-06-23T23:59:59.000Z

334

I n s i t u thermal oxidation for surface cleaning and mask generation prior to selective area epitaxy  

Science Journals Connector (OSTI)

Dry thermal oxidation of GaAs and AlAs has been carried out in an organometallic chemical vapor deposition system. This i n s i t u process performed either before or after an epitaxialgrowth serves the purposes of surface cleaning and mask generation for selective area epitaxy of various III?V semiconductors.AlAsoxidized immediately after growth and patterned for the next regrowth provides better oxide?semiconductor interfaces and minimizes wafer handling. Pre?epitaxy oxidation at 435?°C on a patterned wafer with AlAs/GaAs areas resulted in a selective oxide mask. Since thermal oxides of GaAssublime at temperatures >600?°C a 700?°C pregrowth annealing thus thermally cleans the oxidizedGaAs areas while the oxides of AlAs remain as a mask for the following regrowth. Photoluminescence results indicate that high quality regrown interfaces have been obtained.

Stephen H. Jones; Kei May Lau

1988-01-01T23:59:59.000Z

335

Joint CQSE and CASTS Seminar Weekly Seminar  

E-Print Network [OSTI]

principles calculations, we have explored the effects of mechanical strains on the electronic band gap, VBM/CBM positions, and the effective masses of holes and electrons in anatase TiO2. Our calculations showed of the electronic band gaps of the semiconductor-based photocatalysts such as TiO2 is of great importance

Wu, Yih-Min

336

Wide Bandgap Semiconductors: Essential to Our Technology Future |  

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

Wide Bandgap Semiconductors: Essential to Our Technology Future Wide Bandgap Semiconductors: Essential to Our Technology Future Wide Bandgap Semiconductors: Essential to Our Technology Future January 15, 2014 - 8:00am Addthis Learn how wide bandgap semiconductors could impact clean energy technology and our daily lives. | Video by Sarah Gerrity and Matty Greene, Energy Department. Dr. Ernest Moniz Dr. Ernest Moniz Secretary of Energy What are the key facts? North Carolina State University will lead the Energy Department's new manufacturing innovation institute for the next generation of power electronics, focusing on wide bandgap (WBG) semiconductors. Building America's leadership in WBG semiconductor manufacturing while driving down the cost of the technology could lead to more affordable products for businesses and consumers, billions of dollars in energy

337

Climate VISION: Private Sector Initiatives: Semiconductors: Resources and  

Office of Scientific and Technical Information (OSTI)

Semiconductor Industry Association (SIA) The Semiconductor Industry Association (SIA) is the premier trade association representing the U.S. semiconductor industry. Founded in 1977 by five microelectronics innovators, the SIA has grown to include 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 to advance the competitiveness of the $70 billion U.S. chip industry. Through its national and international network of chief executive officers and working committees, the SIA shapes public policy on issues important to the industry and provides a spectrum of services to help its members grow their businesses. World Semiconductor Council (WSC)

338

Semiconductor and Materials Company Inc SAMCO | Open Energy Information  

Open Energy Info (EERE)

and Materials Company Inc SAMCO and Materials Company Inc SAMCO Jump to: navigation, search Name Semiconductor and Materials Company Inc (SAMCO) Place Kyoto, Kyoto, Japan Zip 612-8443 Sector Solar Product Japanese manufactruer of semiconductor and solar manufacturing equipment such as etching, deposition and cleaning systems. References Semiconductor and Materials Company Inc (SAMCO)[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Semiconductor and Materials Company Inc (SAMCO) is a company located in Kyoto, Kyoto, Japan . References ↑ "Semiconductor and Materials Company Inc (SAMCO)" Retrieved from "http://en.openei.org/w/index.php?title=Semiconductor_and_Materials_Company_Inc_SAMCO&oldid=350738

339

Growth of SiC thin films on graphite for oxidation-protective coating J.-H. Boo,a)  

E-Print Network [OSTI]

, it is necessary to improve its resistance to oxidation. SiC is used as a semiconductor material for high of the SiC layers compared to those grown by thermal MOCVD. The mechanical and oxidation-resistant-2101 00 18204-1 I. INTRODUCTION Graphite, with its advantages of high thermal conductiv- ity, low-thermal

Boo, Jin-Hyo

340

Method and system for powering and cooling semiconductor lasers  

DOE Patents [OSTI]

A semiconductor laser system includes a diode laser tile. The diode laser tile includes a mounting fixture having a first side and a second side opposing the first side and an array of semiconductor laser pumps coupled to the first side of the mounting fixture. The semiconductor laser system also includes an electrical pulse generator thermally coupled to the diode bar and a cooling member thermally coupled to the diode bar and the electrical pulse generator.

Telford, Steven J; Ladran, Anthony S

2014-02-25T23:59:59.000Z

Note: This page contains sample records for the topic "band-gap semiconductor oxide" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Deposition method for producing silicon carbide high-temperature semiconductors  

DOE Patents [OSTI]

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.

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

1987-01-01T23:59:59.000Z

342

Methods and devices for fabricating and assembling printable semiconductor elements  

DOE Patents [OSTI]

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.

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

343

Methods and devices for fabricating and assembling printable semiconductor elements  

DOE Patents [OSTI]

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.

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

344

Methods and devices for fabricating and assembling printable semiconductor elements  

DOE Patents [OSTI]

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.

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

345

Methods and devices for fabricating and assembling printable semiconductor elements  

DOE Patents [OSTI]

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.

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

346

Climate VISION: Private Sector Initiatives: Semiconductors: Resources and  

Office of Scientific and Technical Information (OSTI)

Technical Information Technical Information Download Acrobat Reader Modeling China's Semiconductor Industry Fluorinated Compound Emissions and Drafting a Roadmap for Climate Protection. (PDF 101 KB) 14th Annual International Semiconductor Environment Safety & Health (ISESH) Conference in Jeju, Korea (June 2007) presentation by Scott Bartos, U.S. EPA. Estimating the Impact of Migration to Asian Foundry Production on Attaining the WSC 2010 PFC Reduction Goal. (PDF 458 KB) 11th Annual ISESH Conference in Makuhari, Japan (July 2004) presentation by Scott Bartos, U.S. EPA. Guidelines for Environmental Characterization of Semiconductor Equipment (PDF 361 KB) This document provides guidelines for suppliers of semiconductor processing and abatement equipment to characterize their equipment to meet

347

July 28, 2010, Guiding semiconductor research through collaborative engagement  

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

The SRC ... The SRC ... Guiding semiconductor research through collaborative engagement Elizabeth J. Weitzman Exec. VP, SRC Exec. Director, Focus Center Research Program Semiconductor Research Corporation 2 ... Awarded Nat'l Medal of Technology Presidential Citation: "For building the world's largest and most successful university research force to support the ... semiconductor industry; For proving the concept of collaborative research as the first high-tech research consortium; and For creating the concept and methodology that evolved into the International Technology Roadmap for Semiconductors." 3 Key Attributes of SRC Research Entities 1. Accepted IP model. SRC's model has been

348

Semiconductor research capabilities at the Lawrence Berkeley Laboratory  

SciTech Connect (OSTI)

This document discusses semiconductor research capabilities (advanced materials, processing, packaging) and national user facilities (electron microscopy, heavy-ion accelerators, advanced light source). (DLC)

Not Available

1987-02-01T23:59:59.000Z

349

Method for depositing high-quality microcrystalline semiconductor materials  

DOE Patents [OSTI]

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.

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

2011-03-08T23:59:59.000Z

350

Semiconductor nanowires for photovoltaic and photoelectrochemical energy conversion  

Science Journals Connector (OSTI)

Semiconductor nanowires (NW) possess several beneficial properties for efficient conversion of solar energy into electricity and chemical energy. Due to their efficient absorption of light, short distances for...

Neil P. Dasgupta; Peidong Yang

2014-06-01T23:59:59.000Z

351

Method of transferring a thin crystalline semiconductor layer  

DOE Patents [OSTI]

A method for transferring a thin semiconductor layer from one substrate to another substrate involves depositing a thin epitaxial monocrystalline semiconductor layer on a substrate having surface contaminants. An interface that includes the contaminants is formed in between the deposited layer and the substrate. Hydrogen atoms are introduced into the structure and allowed to diffuse to the interface. Afterward, the thin semiconductor layer is bonded to a second substrate and the thin layer is separated away at the interface, which results in transferring the thin epitaxial semiconductor layer from one substrate to the other substrate.

Nastasi, Michael A. (Sante Fe, NM); Shao, Lin (Los Alamos, NM); Theodore, N. David (Mesa, AZ)

2006-12-26T23:59:59.000Z

352

Multiplex Chaos Synchronization in Semiconductor Lasers with Multiple Optoelectronic Feedbacks  

E-Print Network [OSTI]

Secure chaos based multiplex communication system scheme is proposed utilizing globally coupled semiconductor lasers with multiple variable time delay optoelectronic feedbacks.

E. M. Shahverdiev; K. A. Shore

2011-11-06T23:59:59.000Z

353

Peltier cooling stage utilizing a superconductor-semiconductor junction  

SciTech Connect (OSTI)

This paper describes a Peltier cooling stack. It comprises: a first electrode; a superconducting layer electrically coupled to the first electrode; a semiconducting layer electrically coupled to the superconducting layer; and a second superconducting layer electrically coupled to the semiconductor layer; and a second electrode electrically coupled to the second superconducting layer, electrons flowing under an applied voltage from the first electrode through the first superconducting layer, semiconductor layer, second superconducting layer and second electrode, the electrical junction between the first superconducting layer and semiconductor providing Peltier cooling while the electrical junction between the semiconductor layer and the second superconducting layer providing Peltier heating, whereby a cryogenic Peltier cooling stack is provided.

Skertic, M.M.

1991-04-09T23:59:59.000Z

354

Holey Germanium - New Routes to Ordered Nanoporous Semiconductors  

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

currently exploring a variety of applications for these materials, including nanoscale solar cells and adsorption based chemical sensors. Because the semiconductor surface is...

355

Coherence length tunable semiconductor laser with optical feedback  

Science Journals Connector (OSTI)

We report the experimental results to continuously tune the coherence length of a semiconductor laser using an optical feedback scheme. The coherence length can be controlled by...

Wang, Yuncai; Kong, Lingqin; Wang, Anbang; Fan, Linlin

2009-01-01T23:59:59.000Z

356

Organic Semiconductor Chemistry | MIT-Harvard Center for Excitonics  

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

Organic Semiconductor Chemistry December 13, 2012 at 3pm36-428 Seth Marder Department of ChemistryBiochemistry, Director, Center for Organic Photonics and Electronics, Georgia...

357

Exchange Coupling in the Ferromagnetic Semiconductor GaMnAs.  

E-Print Network [OSTI]

?? The study of ferromagnetic semiconductors (FMS) continues to be of great interest because of their potential for spintronic devices. While there has been much… (more)

Leiner, Jonathan Carl

2012-01-01T23:59:59.000Z

358

Photons, Electrons and Holes: Fundamentals of Photocatalysis with Semiconductors  

Science Journals Connector (OSTI)

Although not all the heterogeneous photocatalysts are semiconductors, this type of solids represents, by far, the most representative and widely investigated photoactive materials. For that reason, the fundamentals

Juan Manuel Coronado

2013-01-01T23:59:59.000Z

359

Exchange interaction studies in magnetic semiconductors by neutron scattering.  

E-Print Network [OSTI]

??Theories predict that making a dilute magnetic semiconductor strongly p -type would allow it to remain ferromagnetic at room temperature. This is of intrest as… (more)

Wiren, Zachary Quincy

2008-01-01T23:59:59.000Z

360

Self-Assembled Monolayers of Alkylphosphonic Acid on GaN Substrates  

Science Journals Connector (OSTI)

In addition to their applications for short-wavelength optoelectronic and high-power electronics, group III nitrides (AlN, GaN, and InN) have been employed as components of chemical and biological sensors for gas and solution samples. ... (27) In the basic solution, ?water decreased quickly to reach a smaller plateau value, probably reflecting the electrostatic repulsion between the deprotonated ODPA and negatively charged gallium oxide surface(46) in addition to the higher solubility of deprotonated ODPA in more basic solution. ... Gallium nitride is a wide band gap semiconductor that demonstrates a unique set of optical and electrical properties as well as aqueous stability and biocompatibility. ...

Takashi Ito; Sarah M. Forman; Chundi Cao; Feng Li; Charles R. Eddy, Jr.; Michael A. Mastro; Ronald T. Holm; Richard L. Henry; Keith L. Hohn; J. H. Edgar

2008-06-04T23:59:59.000Z

Note: This page contains sample records for the topic "band-gap semiconductor oxide" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Pb-free semiconductor ferroelectrics: A theoretical study of Pd-substituted Ba(Ti1-xCex)O3 solid solutions  

E-Print Network [OSTI]

candidates for use as semiconducting ferro- electrics in solar-energy conversion devices. DOI: 10.1103/Phys, though candidate materials are few and far between.1,2 For optimal utilization of the energy in the solar spectrum, a material with a band gap in the range of 1.6­2.0 eV and good charge carrier separation

Rappe, Andrew M.

362

High power semiconductor laser diode arrays  

Science Journals Connector (OSTI)

The cw optical power obtainable from semiconductor laser diodes has been extended to unprecedented levels in recent years through the use of multistripe arrays. By spreading out the optical power with more than 100 stripes single?facet cw output in exces of 5 Watts has been demonstrated and 500 mW cw is now commercially available. Recent improvements to array performance include: arrays up to 1 cm wide that generates quasi?cw (150 usec pulse) output in excesss of 11 Watts and a novel device structure which produces up to 215 mW cw in a single diffraction limited lobe.

Peter S. Cross

1986-01-01T23:59:59.000Z

363

High power semiconductor laser diode arrays  

SciTech Connect (OSTI)

The cw optical power obtainable from semiconductor laser diodes has been extended to unprecedented levels in recent years through the use of multistripe arrays. By spreading out the optical power with more than 100 stripes, single-facet, cw output in exces of 5 Watts has been demonstrated, and 500 mW cw is now commercially available. Recent improvements to array performance include: arrays up to 1 cm wide that generates quasi-cw (150 usec pulse) output in excesss of 11 Watts, and a novel device structure which produces up to 215 mW cw in a single diffraction limited lobe.

Cross, P.S.

1986-08-15T23:59:59.000Z

364

Reusing rinse wastewater at a semiconductor plant  

SciTech Connect (OSTI)

Two pilot rinse wastewater reuse projects were developed as part of a long-term water conservation program for a Motorola semiconductor manufacturing site in Phoenix, Ariz. The conceptual designs for the projects grew out of a detailed wastewater reuse study that characterized wastewater streams at their generation points. Both treatment techniques were specifically researched, bench-tested, and adapted to further water conservation efforts while ensuring 100 percent compliance with appropriate effluent regulations and industrial discharge permit conditions. Together, the pilot projects save the city of Phoenix approximately 45 mil gal (17 {times} 10{sup 4} m{sup 3}) of water annually.

Shah, A.R. [Motorola SCG, McDowell, MD (United States). Environmental, Safety, and Industrial Hygiene Dept.; Ploeser, J.H. [Phoenix Water Services Dept., AZ (United States). Water Conservation Office

1999-08-01T23:59:59.000Z

365

Transient Rayleigh scattering from single semiconductor nanowires  

SciTech Connect (OSTI)

Transient Rayleigh scattering spectroscopy is a new pump-probe technique to study the dynamics and cooling of photo-excited carriers in single semiconductor nanowires. By studying the evolution of the transient Rayleigh spectrum in time after excitation, one can measure the time evolution of the density and temperature of photo-excited electron-hole plasma (EHP) as they equilibrate with lattice. This provides detailed information of dynamics and cooling of carriers including linear and bimolecular recombination properties, carrier transport characteristics, and the energy-loss rate of hot electron-hole plasma through the emission of LO and acoustic phonons.

Montazeri, Mohammad; Jackson, Howard E.; Smith, Leigh M. [Department of Physics, University of Cincinnati, Cincinnati, OH 45221-0011 (United States); Yarrison-Rice, Jan M. [Department of Physics, Miami University, Oxford, OH 45056 (United States); Kang, Jung-Hyun; Gao, Qiang; Tan, Hark Hoe; Jagadish, Chennupati [Department of Electronic Materials Engineering, Research School of Physics and Engineering, The Australian National University, Canberra, ACT 0200 (Australia)

2013-12-04T23:59:59.000Z

366

Silicon metal-semiconductor-metal photodetector  

DOE Patents [OSTI]

Silicon MSM photodiodes sensitive to radiation in the visible to near infrared spectral range are produced by altering the absorption characteristics of crystalline Si by ion implantation. The implantation produces a defected region below the surface of the silicon with the highest concentration of defects at its base which acts to reduce the contribution of charge carriers formed below the defected layer. The charge carriers generated by the radiation in the upper regions of the defected layer are very quickly collected between biased Schottky barrier electrodes which form a metal-semiconductor-metal structure for the photodiode.

Brueck, Steven R. J. (Albuquerque, NM); Myers, David R. (Albuquerque, NM); Sharma, Ashwani K. (Albuquerque, NM)

1997-01-01T23:59:59.000Z

367

Silicon metal-semiconductor-metal photodetector  

DOE Patents [OSTI]

Silicon MSM photodiodes sensitive to radiation in the visible to near infrared spectral range are produced by altering the absorption characteristics of crystalline Si by ion implantation. The implantation produces a defected region below the surface of the silicon with the highest concentration of defects at its base which acts to reduce the contribution of charge carriers formed below the defected layer. The charge carriers generated by the radiation in the upper regions of the defected layer are very quickly collected between biased Schottky barrier electrodes which form a metal-semiconductor-metal structure for the photodiode.

Brueck, Steven R. J. (Albuquerque, NM); Myers, David R. (Albuquerque, NM); Sharma, Ashwani K. (Albuquerque, NM)

1995-01-01T23:59:59.000Z

368

Design Enablement and Design-Centric Assessment of Future Semiconductor Technologies  

E-Print Network [OSTI]

ITRa] International Technology Roadmap for Semiconductors,ITRb] International Technology Roadmap for Semiconductors,val- ues from ITRS technology roadmap [ITRb] and typical

Abou Ghaida, Rani

2012-01-01T23:59:59.000Z

369

On a mathematical model for hot carrier injection in semiconductors  

E-Print Network [OSTI]

On a mathematical model for hot carrier injection in semiconductors Naoufel Ben Abdallah (1) Pierre of a semiconductor device heavily depends on the injection mechanism of carriers into the active regions through by the relation V bi = U th log N + N \\Gamma ; where U th = kBT=q is the thermal voltage and N + ; N \\Gamma

Schmeiser, Christian

370

Magnetically and electrically tunable semiconductor quantum waveguide inverter  

E-Print Network [OSTI]

Magnetically and electrically tunable semiconductor quantum waveguide inverter M. J. Gilbert,a) R implementations. We present an electrically tunable semiconductor quantum waveguide implementation of an inverter. On the other hand, if a ``0'' is present in the control bit, then the qubit is inverted. In a recent study

Gilbert, Matthew

371

Semiconductors 4-bit I2C LED dimmer  

E-Print Network [OSTI]

Philips Semiconductors PCA9533 4-bit I2C LED dimmer Product data sheet Supersedes data of 2003 Sep 19 2004 Oct 01 INTEGRATED CIRCUITS #12;Philips Semiconductors Product data sheet PCA95334-bit I2C LED dimmer 22004 Oct 01 FEATURES · 4 LED drivers (on, off, flashing at a programmable rate) · 2 selectable

Berns, Hans-Gerd

372

Communication using Synchronization of Chaos in Semiconductor Lasers with optoelectronic  

E-Print Network [OSTI]

Communication using Synchronization of Chaos in Semiconductor Lasers with optoelectronic feedback S. The Chaos in the single-mode semiconductor lasers is generated by means of an optoelectronic feedback with optoelectronic feedback has been demonstrated for quite slow data rates by using chaotic wavelength fluctuations

Illing, Lucas

373

Multistability in a semiconductor laser with optoelectronic feedback  

E-Print Network [OSTI]

Multistability in a semiconductor laser with optoelectronic feedback Guang-Qiong Xia1,2 , Sze with delayed optoelectronic feedback is observed experimentally. For a given delay time, the observed dynamical-oscillating semiconductor lasers subject to delayed optoelectronic mutual coupling," Phys. Rev. E 73, 047201-1-4 (2006) 8. G

Chan, Sze-Chun

374

Semiconductor Nanowires for Energy Conversion Allon I. Hochbaum*,  

E-Print Network [OSTI]

Semiconductor Nanowires for Energy Conversion Allon I. Hochbaum*, and Peidong Yang* Department. Introduction: Role of Materials in Energy Conversion 527 2. Why Are Semiconductor Nanowires Special? 527 3 of Materials in Energy Conversion Between 2004 and 2030 the annual global consumption of energy is estimated

Wu, Zhigang

375

Photonic switching devices based on semiconductor nanostructures  

E-Print Network [OSTI]

Focusing and guiding light into semiconductor nanostructures can deliver revolutionary concepts for photonic devices, which offer a practical pathway towards next-generation power-efficient optical networks. In this review, we consider the prospects for photonic switches using semiconductor quantum dots (QDs) and photonic cavities which possess unique properties based on their low dimensionality. The optical nonlinearity of such photonic switches is theoretically analyzed by introducing the concept of a field enhancement factor. This approach reveals drastic improvement in both power-density and speed, which is able to overcome the limitations that have beset conventional photonic switches for decades. In addition, the overall power consumption is reduced due to the atom-like nature of QDs as well as the nano-scale footprint of photonic cavities. Based on this theoretical perspective, the current state-of-the-art of QD/cavity switches is reviewed in terms of various optical nonlinearity phenomena which have been utilized to demonstrate photonic switching. Emerging techniques, enabled by cavity nonlinear effects such as wavelength tuning, Purcell-factor tuning and plasmonic effects are also discussed.

Chao-Yuan Jin; Osamu Wada

2014-02-26T23:59:59.000Z

376

Coated semiconductor devices for neutron detection  

DOE Patents [OSTI]

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.

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

2002-01-01T23:59:59.000Z

377

Distributed Quantum Computation Architecture Using Semiconductor Nanophotonics  

E-Print Network [OSTI]

In a large-scale quantum computer, the cost of communications will dominate the performance and resource requirements, place many severe demands on the technology, and constrain the architecture. Unfortunately, fault-tolerant computers based entirely on photons with probabilistic gates, though equipped with "built-in" communication, have very large resource overheads; likewise, computers with reliable probabilistic gates between photons or quantum memories may lack sufficient communication resources in the presence of realistic optical losses. Here, we consider a compromise architecture, in which semiconductor spin qubits are coupled by bright laser pulses through nanophotonic waveguides and cavities using a combination of frequent probabilistic and sparse determinstic entanglement mechanisms. The large photonic resource requirements incurred by the use of probabilistic gates for quantum communication are mitigated in part by the potential high-speed operation of the semiconductor nanophotonic hardware. The system employs topological cluster-state quantum error correction for achieving fault-tolerance. Our results suggest that such an architecture/technology combination has the potential to scale to a system capable of attacking classically intractable computational problems.

Rodney Van Meter; Thaddeus D. Ladd; Austin G. Fowler; Yoshihisa Yamamoto

2009-09-17T23:59:59.000Z

378

Multilayer films of indium tin oxide/TiO2 codoped with vanadium and nitrogen for efficient photocatalytic water splitting  

Science Journals Connector (OSTI)

TiO22 films codoped with V cations and N anions were synthesised by RF-magnetron sputtering. The incorporation of V and N in TiO2 lattice produces isolated energy levels near the conduction and valence bands, respectively, causing an effective narrowing of the band gap to 2.5 eV. Recombination of photo-charges was reduced by depositing multilayer films of indium tin oxide (ITO)/V-N-codoped TiO2 with different numbers of bilayers. In multilayer structure, the generated photoelectrons, travelling into TiO2 film of limited thickness, rapidly enter the space charge interface of the ITO/TiO2 films from where they are instantaneously injected into the ITO layer and then removed towards the cathode. The synergic effects created by band narrowing and enhanced charge separation by using codoping and multilayer structure strategy in TiO2 generate higher photocurrent for water splitting under visible light which definitely exceeds that obtained by doping TiO2 with a single, V or N, element.

Z. El Koura; N. Patel; R. Edla; A. Miotello

2014-01-01T23:59:59.000Z

379

Life-cycle Assessment of Semiconductors  

E-Print Network [OSTI]

of isopropyl alcohol (IPA), CO, NO X , ethyl lactate andHMDS: hexa-methyl disilizane IPA: isopropyl alcohol OMCTS:liquid H 2 SO 4 HCl NH 4 OH IPA oxide CMP slurry, chemicals

Boyd, Sarah B.

2009-01-01T23:59:59.000Z

380

Organic semiconductors for the new millennium  

Science Journals Connector (OSTI)

...millennium 181 active material indiumtin oxide...electrode, or cathode, since the...func- tion materials are better...electron-injectors (cathodes), whereas high work function materials, such as ITO...non-phosphorescent active materials the...

2000-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "band-gap semiconductor oxide" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Holographic Thin Film System for Multijunction Solar Cells  

Science Journals Connector (OSTI)

The efficiency of photovoltaic generators based on different semiconductor materials with optimized band gaps can achieve considerably higher values than those obtained with single junction solar cells. For th...

W. H. Bloss; M. Griesinger; E. R. Reinhardt

1983-01-01T23:59:59.000Z

382

Celebrating Faculty Excellence acclaiming the awards, honors,  

E-Print Network [OSTI]

of the world's foremost experts on doping wide band-gap semiconductors, creating blue and ultraviolet light-emitting diodes (leds) and lasers that have led to improved consumer products, including sharper laser printers

383

Photoluminescence and Extended X-ray Absorption Fine Structure Studies on CdTe Material.  

E-Print Network [OSTI]

??The direct-band-gap semiconductor CdTe is an important material for fabricating high efficiency, polycrystalline thin-film solar cells in a heterojunction configuration. The outstanding physical properties of… (more)

Liu, Xiangxin

2006-01-01T23:59:59.000Z

384

Temperature dependence of electrical characteristics of Pt/GaN Schottky diode fabricated by UHV e-beam evaporation  

Science Journals Connector (OSTI)

GaN has been the subject of strategic research among all compound semiconductors and has been explored widely and rightly for its various characteristics, like direct wide band gap, high breakdown field, high ...

Ashish Kumar; Shamsul Arafin; Markus Christian Amann…

2013-11-01T23:59:59.000Z

385

Visible and Infra-red Light Emission in Boron-Doped Wurtzite Silicon Nanowires  

E-Print Network [OSTI]

Silicon, the mainstay semiconductor in microelectronic circuitry, is considered unsuitable for optoelectronic applications owing to its indirect electronic band gap, which limits its efficiency as a light emitter. Here we ...

Fabbri, Filippo

386

Design of Shallow P-Type Dopants in ZnO: Preprint  

SciTech Connect (OSTI)

This paper describes approaches to lower the acceptor ionization energy in ZnO by codoping acceptors with donor or isovalent atoms and proposes a universal approach to overcome the doping polarity problem for wide-band-gap semiconductors.

Wei, S.-H.; Li, J.; Yan, Y.

2008-05-01T23:59:59.000Z

387

Control of coherence resonance in semiconductor superlattices  

E-Print Network [OSTI]

We study the effect of time-delayed feedback control and Gaussian white noise on the spatio-temporal charge dynamics in a semiconductor superlattice. The system is prepared in a regime where the deterministic dynamics is close to a global bifurcation, namely a saddle-node bifurcation on a limit cycle ({\\it SNIPER}). In the absence of control, noise can induce electron charge front motion through the entire device, and coherence resonance is observed. We show that with appropriate selection of the time-delayed feedback parameters the effect of coherence resonance can either be enhanced or destroyed, and the coherence of stochastic domain motion at low noise intensity is dramatically increased. Additionally, the purely delay-induced dynamics in the system is investigated, and a homoclinic bifurcation of a limit cycle is found.

Johanne Hizanidis; Eckehard Schoell

2008-09-01T23:59:59.000Z

388

Large-area semiconductor detectors of beta radiation  

SciTech Connect (OSTI)

This paper describes silicon semiconductor detectors with a diameter of 90 mm with hole-type conduction. The detectors had been grown with the Czochralski technique and had a specific resistivity lambda - 12 omega /SUP ./ cm and a carrier lifetime tau = 50 usec. In the case of semiconductor detectors for counting, silicon grown from a melt has its advantages because the distribution of the specific resistivity in low-resistivity semiconductor crystals is more homogeneous than in high-resistivity crystals in both longitudinal and transverse direactions relative to the axis of crystal growth.

Azimov, S.A.; Baizakov, B.B.; Karpov, V.S.; Muminov, R.A.

1986-08-01T23:59:59.000Z

389

Ultrathin amorphous zinc-tin-oxide buffer layer for enhancing heterojunction interface quality in  

E-Print Network [OSTI]

-abundant, non-toxic, and air-stable materials represent a promising class of photovoltaic (PV) devices for cost-effective manufacturing. Earth- abundant metal-oxide semiconductors comprise an attractive set of materials for photovoltaic applications, given their auspicious optoelec- tronic properties and chemical

390

Processing and Characterization of P-Type Doped Zinc Oxide Thin Films  

E-Print Network [OSTI]

Applications of zinc oxide (ZnO) for optoelectronic devices, including light emitting diodes, semiconductor lasers, and solar cells have not yet been realized due to the lack of high-quality p-type ZnO. In the research presented herein, pulsed laser...

Myers, Michelle Anne

2013-03-18T23:59:59.000Z

391

A novel "gelsol" strategy to synthesize TiO2 nanorod combining reduced graphene oxide composites  

E-Print Network [OSTI]

Graphene oxide Titanium dioxide Nanostructure Semiconductors Nanorods a b s t r a c t In this studyH value benefits the deprotonation of TEOA for adsorption to the stationary nuclei. Therefore triethanolamine (TEOA) with titanium (IV) isopropoxide (TIPO) at a molar ratio of [TEOA]:[TIPO]¼2:1, was added

Guo, John Zhanhu

392

Two-dimensional Electron Liquid State at Oxide Interfaces J. Mannhart  

E-Print Network [OSTI]

Two-dimensional Electron Liquid State at Oxide Interfaces J. Mannhart Max Planck InstituteAlO3 #12;LaAlO3 - SrTiO3 YBa2Cu3O7 G. Hammerl #12;Interfaces with Standard Semiconductors: Space Charge;Conductance-voltage characteristics It/ Vs Vs were measured using a standard lock-in technique.24 Simulta

Yeh, Nai-Chang

393

Varian Semiconductor Equipment Associates Inc VSEA | Open Energy  

Open Energy Info (EERE)

Varian Semiconductor Equipment Associates Inc VSEA Varian Semiconductor Equipment Associates Inc VSEA Jump to: navigation, search Name Varian Semiconductor Equipment Associates Inc (VSEA) Place Gloucester, Massachusetts Zip 1930 Sector Services Product Massachusetts-based, designs, manufactures, and services semiconductor processing equipment used in the fabrication of integrated circuits. Coordinates 37.413962°, -76.526305° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":37.413962,"lon":-76.526305,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

394

Ramgraber Semiconductor Equipment GmbH | Open Energy Information  

Open Energy Info (EERE)

Ramgraber Semiconductor Equipment GmbH Ramgraber Semiconductor Equipment GmbH Jump to: navigation, search Name Ramgraber Semiconductor Equipment GmbH Place Brunnthal, Germany Zip 85649 Sector Solar Product Makes semiconductor processing equipment, including solar cell manufacturing lines. Coordinates 48.006898°, 11.684687° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":48.006898,"lon":11.684687,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

395

Argonne licenses diamond semiconductor discoveries to AKHAN Technologies |  

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

licenses diamond semiconductor discoveries to AKHAN Technologies licenses diamond semiconductor discoveries to AKHAN Technologies By Joseph Bernstein * By Jared Sagoff * March 4, 2013 Tweet EmailPrint LEMONT, Ill. - The U.S. Department of Energy's Argonne National Laboratory announced today that the laboratory has granted AKHAN Technologies exclusive diamond semiconductor application licensing rights to breakthrough low-temperature diamond deposition technology developed by Argonne's Center for Nanoscale Materials (CNM). The Argonne-developed technology allows for the deposition of nanocrystalline diamond on a variety of wafer substrate materials at temperatures as low as 400 degrees Celsius. The combination of the Argonne's low-temperature diamond technology with AKHAN's Miraj Diamond(tm) process represents the state of the art in diamond semiconductor

396

Printable semiconductor structures and related methods of making and assembling  

DOE Patents [OSTI]

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.

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

397

Printable semiconductor structures and related methods of making and assembling  

DOE Patents [OSTI]

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.

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

398

Printable semiconductor structures and related methods of making and assembling  

DOE Patents [OSTI]

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.

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

399

Generating dispatching rules for semiconductor manufacturing to minimize weighted tardiness  

Science Journals Connector (OSTI)

Dispatching rules play an important role especially in semiconductor manufacturing scheduling, because these fabrication facilities are characterized by high complexity and dynamics. The process of developing and adapting dispatching rules is currently ...

Christoph Pickardt; Jürgen Branke; Torsten Hildebrandt; Jens Heger; Bernd Scholz-Reiter

2010-12-01T23:59:59.000Z

400

Semiconductor Laser Lidar Wind Velocity Sensor for Turbine Control  

Science Journals Connector (OSTI)

A dual line-of-sight CW lidar that measures both wind speed and direction is presented. The wind lidar employs a semiconductor laser, which allows for inexpensive remote sensors geared...

Rodrigo, Peter John; Hu, Qi; Pedersen, Christian

Note: This page contains sample records for the topic "band-gap semiconductor oxide" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Review of the Semiconductor Industry and Technology Roadmap  

Science Journals Connector (OSTI)

The semiconductor industry operates in a constant state of deflation. It is vital to our survival and progress in this knowledge era. The industry is extremely competitive and requires ongoing technological advan...

Sameer Kumar; Nicole Krenner

2002-09-01T23:59:59.000Z

402

Translating semiconductor device physics into nanoparticle films for electronic applications  

E-Print Network [OSTI]

This thesis explores and quantifies some of the important device physics, parameters, and mechanisms of semiconductor nanocrystal quantum dot (QD) electronic devices, and photovoltaic devices in particular. This involves ...

Wanger, Darcy Deborah

2014-01-01T23:59:59.000Z

403

Improving reuse of semiconductor equipment through benchmarking, standardization, and automation  

E-Print Network [OSTI]

The 6D program at Intel® Corporation was set up to improve operations around capital equipment reuse, primarily in their semiconductor manufacturing facilities. The company was faced with a number of challenges, including ...

Silber, Jacob B. (Jacob Bradley)

2006-01-01T23:59:59.000Z

404

Energy Conservation Through Water Usage Reduction in the Semiconductor Industry  

E-Print Network [OSTI]

ENERGY CONSERVATION THROUGH WATER USAGE REDUCTION IN THE SEMICONDUCTOR INDUSTRY Laura Mendicino Kathy McCormack Sarah Gibson Bob Patton Dana Lyon Jeff Covington Engineer Engineer ESrn Manager Engineer Engineer Engineer Motorola Austin, TX...

Mendicino, L.; McCormack, K.; Gibson, S.; Patton, B.; Lyon, D.; Covington, J.

405

Facts and Artifacts in the Blinking Statistics of Semiconductor Nanocrystals  

Science Journals Connector (OSTI)

Since its initial discovery just over a decade ago, blinking of semiconductor nanocrystals has typically been described in terms of probability distributions for durations of bright, or “on,” states and dark, or “off,” states. These distributions are ...

Catherine H. Crouch; Orion Sauter; Xiaohua Wu; Robert Purcell; Claudia Querner; Marija Drndic; Matthew Pelton

2010-04-05T23:59:59.000Z

406

Data sheet acquired from Harris Semiconductor Buffered Inputs  

E-Print Network [OSTI]

1 Data sheet acquired from Harris Semiconductor SCHS121D Features · Buffered Inputs · Typical. The suffixes 96 and R denote tape and reel. The suffix T denotes a small-quantity reel of 250. CAUTION

Kretchmar, R. Matthew

407

Data sheet acquired from Harris Semiconductor Four Operating Modes  

E-Print Network [OSTI]

1 Data sheet acquired from Harris Semiconductor SCHS164F Features · Four Operating Modes - Shift Ld PDIP NOTE: When ordering, use the entire part number. The suffixes 96 and R denote tape and reel

Kretchmar, R. Matthew

408

Semiconductor Aspects of Organic Bulk Heterojunction Solar Cells  

Science Journals Connector (OSTI)

During the last few years organic solar cells have been discussed as a promising alternative to inorganic semiconductors for renewable energy production. These organic photovoltaic devices offer the possibility o...

Christoph J. Brabec

2003-01-01T23:59:59.000Z

409

Ultrafast nonlinear optical properties of passive and active semiconductor devices  

E-Print Network [OSTI]

Nonlinear optical properties and ultrafast carrier dynamics of slab-coupled optical waveguide amplifiers, silicon nanowaveguides, and III-V semiconductor saturable Bragg reflectors are studied. The limits imposed by two ...

Motamedi, Ali Reza

2011-01-01T23:59:59.000Z

410

Phenomenological band structure model of magnetic coupling in semiconductors  

E-Print Network [OSTI]

Phenomenological band structure model of magnetic coupling in semiconductors Gustavo M. Dalpian a,1­18]. Several models have been proposed to explain the phenomena, including the phenomenological Zener

Gong, Xingao

411

Oxidation of Propane by Doped Nickel Oxides  

Science Journals Connector (OSTI)

... present study, however, indicate that in the absence of excess oxygen, direct oxidation of propane by the oxide lattice can occur.

D. W. McKEE

1964-04-11T23:59:59.000Z

412

A Fully Integrated Nanosystem of Semiconductor Nanowires for Direct Solar Water Splitting  

SciTech Connect (OSTI)

Artificial photosynthesis, the biomimetic approach to converting sunlight?s energy directly into chemical fuels, aims to imitate nature by using an integrated system of nanostructures, each of which plays a specific role in the sunlight-to-fuel conversion process. Here we describe a fully integrated system of nanoscale photoelectrodes assembled from inorganic nanowires for direct solar water splitting. Similar to the photosynthetic system in a chloroplast, the artificial photosynthetic system comprises two semiconductor light absorbers with large surface area, an interfacial layer for charge transport, and spatially separated cocatalysts to facilitate the water reduction and oxidation. Under simulated sunlight, a 0.12percent solar-to-fuel conversion efficiency is achieved, which is comparable to that of natural photosynthesis. The result demonstrates the possibility of integrating material components into a functional system that mimics the nanoscopic integration in chloroplasts. It also provides a conceptual blueprint of modular design that allows incorporation of newly discovered components for improved performance.

Liu, Chong; Tang, Jinyao; Chen, HaoMing; Liu, Bin; Yang, Peidong

2013-02-21T23:59:59.000Z

413

Thermally robust semiconductor optical amplifiers and laser diodes  

DOE Patents [OSTI]

A highly heat conductive layer is combined with or placed in the vicinity of the optical waveguide region of active semiconductor components. The thermally conductive layer enhances the conduction of heat away from the active region, which is where the heat is generated in active semiconductor components. This layer is placed so close to the optical region that it must also function as a waveguide and causes the active region to be nearly the same temperature as the ambient or heat sink. However, the semiconductor material itself should be as temperature insensitive as possible and therefore the invention combines a highly thermally conductive dielectric layer with improved semiconductor materials to achieve an overall package that offers improved thermal performance. The highly thermally conductive layer serves two basic functions. First, it provides a lower index material than the semiconductor device so that certain kinds of optical waveguides may be formed, e.g., a ridge waveguide. The second and most important function, as it relates to this invention, is that it provides a significantly higher thermal conductivity than the semiconductor material, which is the principal material in the fabrication of various optoelectronic devices.

Dijaili, Sol P. (Moraga, CA); Patterson, Frank G. (Danville, CA); Walker, Jeffrey D. (El Cerrito, CA); Deri, Robert J. (Pleasanton, CA); Petersen, Holly (Manteca, CA); Goward, William (Antioch, CA)

2002-01-01T23:59:59.000Z

414

Exploring Visible-Light-Responsive Photocatalysts for Water Splitting Based on Novel Band-gap Engineering Strategies  

E-Print Network [OSTI]

Chapter 4 Boron Carbides as Efficient, Metal-Free, Visible-and transition metals, the boron carbide products werex Chapter Boron Carbides as Efficient, Metal-free, Visible-

Liu, Jikai

2013-01-01T23:59:59.000Z

415

Quasiparticle band structure and density-functional theory: Single-particle excitations and band gaps in lattice models  

E-Print Network [OSTI]

ARTICLES Quasiparticle band structure and density-functional theory: Single-particle excitations-particle eigenvalues. Without rigorous basis even for the exact density-functional theory , these are often taken, eigenvalues obtained from density-functional theory DFT , and those from a corresponding LDA. Notable among

Hess, Daryl W.

416

OPTIMIZATION OF GRADED BAND GAP CdHgTe SOLAR CELLS A. BOUAZZI (*), Y. MARFAING and J. MIMILA-ARROYO  

E-Print Network [OSTI]

limited to 6 % in Cu2Te/CdTe junctions [4, 5], 7.9 % in CdS/CdTe heterojunctions and 6 % in homojunc with uniform doping followed by a base region with uni- form gap and doping. Our goal is to find the optimum

Boyer, Edmond

417

One-photon band gap engineering of borate glass doped with ZnO for photonics applications  

SciTech Connect (OSTI)

Lithium tungsten borate glass of the composition (0.56-x)B{sub 2}O{sub 3}-0.4Li{sub 2}O-xZnO-0.04WO{sub 3} (0 {<=}x{<=} 0.1 mol. %) is prepared for photonics applications. The glass is doped with ZnO to tune the glass absorption characteristics in a wide spectrum range (200-2500 nm). Chemical bond approach, including chemical structure, electronegativity, bond ionicity, nearest-neighbor coordination, and other chemical bonding aspect, is used to analyze and to explain the obtained glass properties such as: transmittance, absorption, electronic structure parameters (bandgap, Fermi level, and Urbach exciton-phonon coupling), Wannier free excitons excitation (applying Elliott's model), and two-photon absorption coefficient as a result of replacement of B{sub 2}O{sub 3} by ZnO.

Abdel-Baki, Manal [Glass Department, National Research Centre, Dokki 12311 Giza (Egypt); Abdel-Wahab, Fathy A.; El-Diasty, Fouad [Physics Department, Faculty of Science, Ain Shams University, Abbasia, 11566 Cairo (Egypt)

2012-04-01T23:59:59.000Z

418

Band offsets of Al{sub 2}O{sub 3} and HfO{sub 2} oxides deposited by atomic layer deposition technique on hydrogenated diamond  

SciTech Connect (OSTI)

High-k oxide insulators (Al{sub 2}O{sub 3} and HfO{sub 2}) have been deposited on a single crystalline hydrogenated diamond (H-diamond) epilayer by an atomic layer deposition technique at temperature as low as 120 Degree-Sign C. Interfacial electronic band structures are characterized by X-ray photoelectron spectroscopy. Based on core-level binding energies and valence band maximum values, valence band offsets are found to be 2.9 {+-} 0.2 and 2.6 {+-} 0.2 eV for Al{sub 2}O{sub 3}/H-diamond and HfO{sub 2}/H-diamond heterojunctions, respectively. Band gaps of the Al{sub 2}O{sub 3} and HfO{sub 2} have been determined to be 7.2 {+-} 0.2 and 5.4 {+-} 0.2 eV by measuring O 1s energy loss spectra, respectively. Both the Al{sub 2}O{sub 3}/H-diamond and HfO{sub 2}/H-diamond heterojunctions are concluded to be type-II staggered band configurations with conduction band offsets of 1.2 {+-} 0.2 and 2.7 {+-} 0.2 eV, respectively.

Liu, J. W.; Liao, M. Y.; Imura, M. [Optical and Electronic Materials Unit, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Koide, Y. [Optical and Electronic Materials Unit, National Institute for Materials Science (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)

2012-12-17T23:59:59.000Z

419

The origin of 2.7 eV luminescence and 5.2 eV excitation band in hafnium oxide  

SciTech Connect (OSTI)

The origin of a blue luminescence band at 2.7 eV and a luminescence excitation band at 5.2 eV of hafnia has been studied in stoichiometric and non-stoichiometric hafnium oxide films. Experimental and calculated results from the first principles valence band spectra showed that the stoichiometry violation leads to the formation of the peak density of states in the band gap caused by oxygen vacancies. Cathodoluminescence in the non-stoichiometric film exhibits a band at 2.65 eV that is excited at the energy of 5.2 eV. The optical absorption spectrum calculated for the cubic phase of HfO{sub 2} with oxygen vacancies shows a peak at 5.3?eV. Thus, it could be concluded that the blue luminescence band at 2.7?eV and HfO{sub x} excitation peak at 5.2?eV are due to oxygen vacancies. The thermal trap energy in hafnia was estimated.

Perevalov, T. V., E-mail: timson@isp.nsc.ru [A. V. Rzhanov Institute of Semiconductor Physics of SB RAS, 13 Lavrentieva Ave, 630090 Novosibirsk (Russian Federation); Novosibirsk State University, 2 Pirogova St., 630090 Novosibirsk (Russian Federation); Aliev, V. Sh.; Gritsenko, V. A. [A. V. Rzhanov Institute of Semiconductor Physics of SB RAS, 13 Lavrentieva Ave, 630090 Novosibirsk (Russian Federation); Saraev, A. A. [Boreskov Institute of Catalysis of SB RAS, 5 Lavrentieva Ave, 630090 Novosibirsk (Russian Federation); Kaichev, V. V. [Novosibirsk State University, 2 Pirogova St., 630090 Novosibirsk (Russian Federation); Boreskov Institute of Catalysis of SB RAS, 5 Lavrentieva Ave, 630090 Novosibirsk (Russian Federation); Ivanova, E. V.; Zamoryanskaya, M. V. [Ioffe Physicotechnical Institute of RAS, 26 Politechnicheskaya St., 194021 St. Petersburg (Russian Federation)

2014-02-17T23:59:59.000Z

420

Improved Initial Performance of Si Nanoparticles by Surface Oxide Reduction  

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

Improved Initial Performance of Si Nanoparticles by Surface Oxide Reduction Improved Initial Performance of Si Nanoparticles by Surface Oxide Reduction for Lithium-Ion Battery Application Title Improved Initial Performance of Si Nanoparticles by Surface Oxide Reduction for Lithium-Ion Battery Application Publication Type Journal Article Year of Publication 2011 Authors Xun, Shidi, Xiangyun Song, Michael E. Grass, Daniel K. Roseguo, Z. Liu, Vincent S. Battaglia, and Gao Li Journal Electrochemical Solid-State Letters Volume 14 Start Page A61 Issue 5 Pagination A61-A63 Date Published 02/2001 Keywords Electrochemistry, elemental semiconductors, etching, lithium, nanoparticles, secondary cells, silicon, thermal analysis, transmission electron microscopy, X-ray photoelectron spectra Abstract This study characterizes the native oxide layer of Si nanoparticles and evaluates its effect on their performance for Li-ion batteries. x-ray photoelectron spectroscopy and transmission electron microscopy were applied to identify the chemical state and morphology of the native oxide layer. Elemental and thermogravimetric analysis were used to estimate the oxide content for the Si samples. Hydrofluoric acid was used to reduce the oxide layer. A correlation between etching time and oxide content was established. The initial electrochemical performances indicate that the reversible capacity of etched Si nanoparticles was enhanced significantly compared with that of the as-received Si sample.

Note: This page contains sample records for the topic "band-gap semiconductor oxide" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Growth and properties of crystalline barium oxide on the GaAs(100) substrate  

SciTech Connect (OSTI)

Growing a crystalline oxide film on III-V semiconductor renders possible approaches to improve operation of electronics and optoelectronics heterostructures such as oxide/semiconductor junctions for transistors and window layers for solar cells. We demonstrate the growth of crystalline barium oxide (BaO) on GaAs(100) at low temperatures, even down to room temperature. Photoluminescence (PL) measurements reveal that the amount of interface defects is reduced for BaO/GaAs, compared to Al{sub 2}O{sub 3}/GaAs, suggesting that BaO is a useful buffer layer to passivate the surface of the III-V device material. PL and photoemission data show that the produced junction tolerates the post heating around 600?°C.

Yasir, M.; Dahl, J.; Lång, J.; Tuominen, M.; Punkkinen, M. P. J.; Laukkanen, P., E-mail: pekka.laukkanen@utu.fi; Kokko, K. [Department of Physics and Astronomy, University of Turku, FI-20014 Turku (Finland)] [Department of Physics and Astronomy, University of Turku, FI-20014 Turku (Finland); Kuzmin, M. [Department of Physics and Astronomy, University of Turku, FI-20014 Turku (Finland) [Department of Physics and Astronomy, University of Turku, FI-20014 Turku (Finland); Ioffe Physical-Technical Institute, Russian Academy of Sciences, St. Petersburg 194021 (Russian Federation); Korpijärvi, V.-M.; Polojärvi, V.; Guina, M. [Optoelectronics Research Centre, Tampere University of Technology, FI-33101 Tampere (Finland)] [Optoelectronics Research Centre, Tampere University of Technology, FI-33101 Tampere (Finland)

2013-11-04T23:59:59.000Z

422

OPTICAL AND DYNAMIC PROPERTIES OF UNDOPED AND DOPED SEMICONDUCTOR NANOSTRUCTURES  

SciTech Connect (OSTI)

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.

Grant, C D; Zhang, J Z

2007-09-28T23:59:59.000Z

423

Optoelectronic cooling of mechanical modes in a semiconductor nanomembrane  

E-Print Network [OSTI]

Optical cavity cooling of mechanical resonators has recently become a research frontier. The cooling has been realized with a metal-coated silicon microlever via photo-thermal force and subsequently with dielectric objects via radiation pressure. Here we report cavity cooling with a crystalline semiconductor membrane via a new mechanism, in which the cooling force arises from the interaction between the photo-induced electron-hole pairs and the mechanical modes through the deformation potential coupling. The optoelectronic mechanism is so efficient as to cool a mode down to 4 K from room temperature with just 50 uW of light and a cavity with a finesse of 10 consisting of a standard mirror and the sub-wavelength-thick semiconductor membrane itself. The laser-cooled narrow-band phonon bath realized with semiconductor mechanical resonators may open up a new avenue for photonics and spintronics devices.

K. Usami; A. Naesby; T. Bagci; B. Melholt Nielsen; J. Liu; S. Stobbe; P. Lodahl; E. S. Polzik

2010-11-22T23:59:59.000Z

424

In situ examination of tin oxide atomic layer deposition using quartz crystal microbalance and Fourier transform infrared techniques  

E-Print Network [OSTI]

-type semiconductor metal oxide that has many applications in various fields due to its special optical, electrical capacity anode for next gen- eration lithium ion batteries.3,4 SnO2 can also be used as a catalyst typically around 10-2 cm. The adsorp- tion of O2 from air removes the electron charge carriers from

George, Steven M.

425

Modeling of electroabsorption in semiconductor quantum structures within the eight-band k?p theory  

Science Journals Connector (OSTI)

We have incorporated electric fields into the eight-band k?p theory, which we have applied to heterostructures, in conjunction with the envelope-function approximation. We use the method of Baraff and Gershoni to implement the electric-field effects in a computer program that calculates the optical properties of direct-band-gap heterostructures in one, two, and three dimensions. Using this method, we calculate the interband and intersubband electroabsorption of multiple quantum wells as well as the interband electroabsorption in superlattices. We illustrate the evolution of the Stark localization of the electron wave function under the application of an external electric field in superlattices. Comparison with experimental data, available in the literature, exhibits very good agreement between theory and experiment, with respect to the spectral shape, the absolute magnitude, and the electric-field dependence of the absorption.

Mats-Erik Pistol and David Gershoni

1994-10-15T23:59:59.000Z

426

Electrocoagulation: A Technology for Water Recycle and Wastewater Treatment in Semiconductor Manufacturing  

E-Print Network [OSTI]

Electrocoagulation: A Technology for Water Recycle and Wastewater Treatment in Semiconductor of treating wastewater streams in the semiconductor manufacturing industry. Electrocoagulation involves wastewater is increasing greatly. The objective is that by using EC to treat wastewater streams, this water

Fay, Noah

427

Unusual Bi-Containing Surface Layers of III–V Compound Semiconductors  

Science Journals Connector (OSTI)

In this chapter, it is first described how the surface science and engineering of the III–V compound semiconductors are relevant to developing the semiconductor-based materials, including bismuth (Bi) containi...

Pekka Laukkanen; Marko Punkkinen

2013-01-01T23:59:59.000Z

428

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

DOE Patents [OSTI]

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.

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

2014-08-19T23:59:59.000Z

429

E-Print Network 3.0 - active fabry-perot semiconductor Sample...  

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

Physics 45 The Laser DiodeThe Laser Diode Jason HillJason Hill Summary: to a Light Emitting Diode Active medium is a semiconductor pActive medium is a semiconductor p--n...

430

Thin film reactions on alloy semiconductor substrates  

SciTech Connect (OSTI)

The interactions between Pt and In{sub .53}Ga{sub .47}As have been studied. In{sub .53}Ga{sub .47}As substrates with 70nm Pt films were encapsulated in SiO{sub 2}, and annealed up to 600{degree}C in flowing forming gas. The composition and morphology of the reaction product phases were studied using x-ray diffraction, Auger depth profiling, and transmission electron microscopy. The reaction kinetics were examined with Rutherford Backscattering. Results show that Pt/In{sub .53}Ga{sub .47}As reacts to form many of the reaction products encountered in the Pt/GaAs and Pt/InP reactions: PtGa, Pt{sub 3}Ga, and PtAs{sub 2}. In addition, a ternary phase, Pt(In:Ga){sub 2}, develops, which is a solid solution between PtIn{sub 2} and PtGa{sub 2}. The amount of Ga in the ternary phase increases with annealing temperature, which causes a decrease in the lattice parameter of the phase. The reaction products show a tendency to form layered structures, especially for higher temperatures and longer annealing times. Unlike the binary case, the PtAs{sub 2}, phase is randomly oriented on the substrate, and is intermingle with a significant amount of Pt(In:Ga){sub 2}. Following Pt/In{sub .53}Ga{sub .47}As reactions, two orientation relationships between the Pt(In:Ga){sub 2} product phase and the substrate were observed, despite the large mismatch with the substrate ({approximately}8%). For many metal/compound semiconductor interactions, the reaction rate is diffusion limited, i.e. exhibits a parabolic dependence on time. An additional result of this study was the development of an In-rich layer beneath the reacted layer. The Auger depth profile showed a substantial increase in the sample at this layer. This is a significant result for the production of ohmic contacts, as the Schottky barrier height in this system lower for higher In concentrations. 216 refs.

Olson, D.A.

1990-11-01T23:59:59.000Z

431

Toward a Unified Treatment of Electronic Processes in Organic Semiconductors  

SciTech Connect (OSTI)

A quantitative study of n-type doping in highly crystalline organic semiconductor films establishes the predominant influence of electrostatic forces in these low-dielectric materials. Based on these findings, a self-consistent model of doped (purposely or not) organic semiconductors is proposed in which: (1) the equilibrium free carrier density, nf, is a small fraction of the total charge density; (2) a superlinear increase in conductivity with doping density is universal; (3) nf increases with applied electric field; and (4) the carrier mobility is field-dependent regardless of crystallinity.

Gregg. B.A.

2005-01-01T23:59:59.000Z

432

Theory and Design of Smith-Purcell Semiconductor Terahertz Sources  

E-Print Network [OSTI]

-power semiconductor devices, but have also been demonstrated to be highly useful in the development of state of the art light emitting diode (LED) technology. One of the more promising LED materials, gallium nitride (GaN) comes from the “three-nitride” (III-N) family...-power semiconductor devices, but have also been demonstrated to be highly useful in the development of state of the art light emitting diode (LED) technology. One of the more promising LED materials, gallium nitride (GaN) comes from the “three-nitride” (III-N) family...

Smith, Don DeeWayne

2013-12-06T23:59:59.000Z

433

POWER SEMICONDUCTORS—STATE OF ART AND FUTURE TRENDS  

Science Journals Connector (OSTI)

The importance of effective energy conversion control including power generation from renewable and environmentally clean energy sources increases due to rising energy demand. Power electronic systems for controlling and converting electrical energy have become the workhorse of modern society in many applications both in industry and at home. Power electronics plays a very important role in traction and can be considered as brawns of robotics and automated manufacturing systems. Power semiconductor devices are the key electronic components used in power electronic systems. Advances in power semiconductor technology have improved the efficiency size weight and cost of power electronic systems.

Vitezslav Benda

2011-01-01T23:59:59.000Z

434

E-Print Network 3.0 - advanced semiconductor devices Sample Search...  

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

Northern Illinois University Collection: Engineering 39 Kompetenzzentrum fr Automobil-und Industrieelektronik Summary: of materials for these advanced semiconductor...

435

Contact formation and gettering of precipitated impurities by multiple firing during semiconductor device fabrication  

DOE Patents [OSTI]

Methods for contact formation and gettering of precipitated impurities by multiple firing during semiconductor device fabrication are provided. In one embodiment, a method for fabricating an electrical semiconductor device comprises: a first step that includes gettering of impurities from a semiconductor wafer and forming a backsurface field; and a second step that includes forming a front contact for the semiconductor wafer, wherein the second step is performed after completion of the first step.

Sopori, Bhushan

2014-05-27T23:59:59.000Z

436

Asphalt Oxidation Kinetics and Pavement Oxidation Modeling  

E-Print Network [OSTI]

Most paved roads in the United States are surfaced with asphalt. These asphalt pavements suffer from fatigue cracking and thermal cracking, aggravated by the oxidation and hardening of asphalt. This negative impact of asphalt oxidation on pavement...

Jin, Xin

2012-07-16T23:59:59.000Z

437

Visible Light Photocatalysis with Platinized Rutile TiO2 for Aqueous Organic Oxidation  

E-Print Network [OSTI]

chemicals containing different functional groups (formic acid, salicylic acid, 4-chlorophenol, 2,4,6-trichlorophenol, diethyl phosphoramidate) were selected for photooxidationtestswith 1/2 wt about 4% of the solar spectrum, the need to develop photocatalysts with smaller band gaps is paramount.6

Boolchand, Punit

438

Laser Cooling of a Semiconductor by 40 Kelvin: An Optical Refrigerator Based on Cadmium Sulfide Nanoribbons  

E-Print Network [OSTI]

of semiconductors using CdS nanoribbons (or nanobelts) in this work. This net cooling effect is found: Optical refrigeration, Laser cooling of semiconductors, CdS nanobelts, anti-Stokes luminescence 1) doped crystals or glasses and direct bandgap semiconductors. Rare-earth doped materials were proposed

Xiong, Qihua

439

Streamlining the supply chain information system of the semiconductor industry using multi-XML schema  

Science Journals Connector (OSTI)

This study develops a supply chain informational infrastructure that streamlines message exchange among partners in the semiconductor industry to enhance the performance of the semiconductor industry's supply chain system, from the upstream IC design ... Keywords: XML), e-commerce, electronic commerce, extensible markup language (, metadata 1, production information management, semiconductor industry supply chain

Ruey-Shun Chen; Kung-Yung Lu; Yen-Ming Chu

2004-05-01T23:59:59.000Z

440

A High Through-put Combinatorial Growth Technique for Semiconductor Thin Film Search  

SciTech Connect (OSTI)

Conventional semiconductor material growth technique is costly and time-consuming. Here we developed a new method to growth semiconductor thin films using high through-put combinatorial technique. In this way, we have successfully fabricated tens of semiconductor libraries with high crystallinity and high product of {mu}{tau} for the purpose of radiation detection.

Ma, Z. X.; Hao, H. Y.; Xiao, P.; Oehlerking, L. J.; Liu, D. F.; Zhang, X. J.; Yu, K.-M.; Walukiewicz, W.; Mao, S. S. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Yu, P. Y. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Department of Physics, University of California, Berkeley, CA 94720 (United States)

2011-12-23T23:59:59.000Z

Note: This page contains sample records for the topic "band-gap semiconductor oxide" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Advanced semiconductor fabrication process control using dual filter exponentially weighted moving average  

Science Journals Connector (OSTI)

Semiconductor industry needs to meet high standards to ensure survival and success in the 21st century. Rising expectations from the customers are demanding the semiconductor industry to manufacture products with both accuracy and precision. To comply ... Keywords: Dual filter EWMA, EWMA, Process control, Run-to-run, Semiconductor fabrication process

Hyo-Heon Ko; Jihyun Kim; Sang-Hoon Park; Jun-Geol Baek; Sung-Shick Kim

2012-06-01T23:59:59.000Z

442

CASP | U.S. DOE Office of Science (SC)  

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

CASP CASP Energy Frontier Research Centers (EFRCs) EFRCs Home Centers Research Science Highlights News & Events Publications Contact BES Home Centers CASP Print Text Size: A A A RSS Feeds FeedbackShare Page Center for Advanced Solar Photophysics (CASP) Director(s): Victor I. Klimov Lead Institution: Los Alamos National Laboratory Mission: To capitalize on recent advances in the science of how nanoparticles interact with light to design highly efficient materials for the conversion of sunlight into electricity. Research Topics: solar (photovoltaic), solar (fuels), solid state lighting, bio-inspired, electrodes - solar, defects, charge transport, materials and chemistry by design, optics, synthesis (novel materials), synthesis (scalable processing) Materials Studied: MATERIALS: semiconductor, wide band-gap semiconductor, metal, oxide,

443

Ados Co Ltd Dong Yang Semiconductor | Open Energy Information  

Open Energy Info (EERE)

Ados Co Ltd Dong Yang Semiconductor Ados Co Ltd Dong Yang Semiconductor Jump to: navigation, search Name Ados Co Ltd (Dong Yang Semiconductor) Place Seoul, Seoul, Korea (Republic) Product Korean manufacturer of semiconductors; through Ersol's technology, will develop PV plants and begin to roll out crystalline silicon wafers and cells by H2 2007. Coordinates 37.557121°, 126.977379° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":37.557121,"lon":126.977379,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

444

Semiconductor Components Industries, LLC, 2004 July, 2004 -Rev. 13  

E-Print Network [OSTI]

© Semiconductor Components Industries, LLC, 2004 July, 2004 - Rev. 13 Publication Order Number: LM339/D 1 LM339, LM239, LM2901, LM2901V, NCV2901, MC3302 Single Supply Quad Comparators://onsemi.com TSSOP-14 DTB SUFFIX CASE 948G 1 14 #12;LM339, LM239, LM2901, LM2901V, NCV2901, MC3302 http

Ravikumar, B.

445

Electric-dipole-induced spin resonance in disordered semiconductors  

E-Print Network [OSTI]

ARTICLES Electric-dipole-induced spin resonance in disordered semiconductors MATHIAS DUCKHEIM One of the hallmarks of spintronics is the control of magnetic moments by electric fields enabled in such structures is electric-dipole-induced spin resonance (EDSR), where the radio-frequency fields driving

Loss, Daniel

446

Freescale Semiconductor Successfully Implements an Energy Management System  

Broader source: Energy.gov [DOE]

This case study describes how Freescale Semiconductor implemented projects at its Oak Hill Fab plant in Austin, Texas, that reduced annual plant-wide energy consumption by 28 million kilowatt hours (kWh) of electricity and 26,000 million British thermal units (Btu) of natural gas between 2006 and 2009, saving more than $2 million each year.

447

Optical absorption intensity of semiconductor single-wall carbon nanotubes  

E-Print Network [OSTI]

Optical absorption intensity of semiconductor single-wall carbon nanotubes Y. Oyama1 , R. Saito1. The optical absorption intensity is inversely proportional to the diameter in the unit of per carbon atom of single-wall carbon nanotubes (SWNT) synthesized by alcohol CCVD (ACCVD) method and HiPco method [1

Maruyama, Shigeo

448

Wide Bandgap Semiconductors for Power Electronics, Optoelectronics, and Advanced Communications  

E-Print Network [OSTI]

Wide Bandgap Semiconductors for Power Electronics, Optoelectronics, and Advanced Communications with material composition over a range of 0.7 to 5 eV. This factor allows them to be used for optoelectronic. Improvement in growth quality and doping of GaN is needed to improve the performance of optoelectronics

Li, Mo

449

CHARACTERISATION OF SEMICONDUCTOR OPTICAL AMPLIFIERS FOR ALL-OPTICAL REGENERATION  

E-Print Network [OSTI]

electrical pumping, broad spectral range and opportunities for integration and mass production. Among these components, the semiconductor optical amplifier (SOA) with gain saturation, low optical and electrical power Various SOAs from Alcatel-Thales III-V lab were characterized in the framework of the French project FUTUR

Paris-Sud XI, Université de

450

Electronic displays using optically pumped luminescent semiconductor nanocrystals  

SciTech Connect (OSTI)

A multicolor electronic display is based on an array of luminescent semiconductor nanocrystals. Nanocrystals which emit tight of different colors are grouped into pixels. The nanocrystals are optically pumped to produce a multicolor display. Different sized nanocrystals are used to produce the different colors. A variety of pixel addressing systems can be used.

Weiss, Shimon; Schlam, Michael C; Alivisatos, A. Paul

2014-03-25T23:59:59.000Z

451

Profiling the Thermoelectric Power of Semiconductor Junctions with  

E-Print Network [OSTI]

sources realize energy conversion between heat and electricity without the use of moving me- chanical the thermoelectric power, band struc- tures, and carrier concentrations of semiconductor junctions that constitute S is governed by local carrier statistics, SThEM allows us to profile precise elec- tronic junction locations

452

Hydrogen in compound semiconductors M. D. McCluskeya)  

E-Print Network [OSTI]

Hydrogen in compound semiconductors M. D. McCluskeya) and N. M. Johnson Xerox Palo Alto Research Center, Palo Alto, California 94304 Received 9 October 1998; accepted 18 December 1998 Hydrogen can consequence of hydrogenation is the passivation of dopant impurities, which leads to a decrease

McCluskey, Matthew

453

FLUID MECHANICS AND HEAT TRANSFER OF ELECTRON FLOW IN SEMICONDUCTORS  

E-Print Network [OSTI]

= heat, f = LO-mode, g = LO, h = LA-mode, i = negligible, j = remote heat sink 7/ 70 #12;Heat conductionFLUID MECHANICS AND HEAT TRANSFER OF ELECTRON FLOW IN SEMICONDUCTORS Mihir Sen Department · Shallow water analogy · Vorticity dynamics · Linear stability analysis · Numerical simulations of heat

Sen, Mihir

454

Semiconductor gamma radiation detectors: band structure effects in energy resolution  

E-Print Network [OSTI]

high precision and in a broad energy range, the number of created pairs N is just proportional (referred to as the pair excitation energy). For semiconductor materials the pair excitation energy becomes important in the search for materials with improved energy resolution. #12;Theoretical models used

Luryi, Serge

455

Method for altering the luminescence of a semiconductor  

DOE Patents [OSTI]

A method is described for altering the luminescence of a light emitting semiconductor (LES) device. In particular, a method is described whereby a silicon LES device can be selectively irradiated with a radiation source effective for altering the intensity of luminescence of the irradiated region. 4 figs.

Barbour, J.C.; Dimos, D.B.

1999-01-12T23:59:59.000Z

456

Fully Integrated Complementary Metal Oxide Semiconductor (CMOS) Bio-Assay Platform  

E-Print Network [OSTI]

PON IVD platform, namely high bio- chemical sensitivity andthat this platform had the bio- chemical selectivityThe bio-chemical sensitivity of this platform was evaluated

Florescu, Octavian

2010-01-01T23:59:59.000Z

457

Atomic scale studies of interface formation between oxides and III-V semiconductor surfaces  

E-Print Network [OSTI]

112 Figure 35. Reaction of IPA with InAs(0 0 1)-(4 × 2) vs.116 Figure 36. IPA dosing at 25 °C and annealing at 200 °C,121 vii STS measurements for IPA, H 2 O, HOOH on n- and p-

Clemens, Jonathon Boyd

2010-01-01T23:59:59.000Z

458

Synthesis, Characterization, and Ultrafast Dynamics of Metal, Metal Oxide, and Semiconductor Nanomaterials  

E-Print Network [OSTI]

electron storage, electrochromic, and photoelectrochromicV. Thin Solid Films Electrochromic and photoelectrochemical

Wheeler, Damon Andreas

2013-01-01T23:59:59.000Z

459

Atomic scale studies of interface formation between oxides and III-V semiconductor surfaces  

E-Print Network [OSTI]

King, CRC Handbook of Chemistry and Physics, 89th Edition,Luo, CRC Handbook of Chemistry and Physics, 89th Edition,in CRC Handbook of Chemistry and Physics, 90th edition (

Clemens, Jonathon Boyd

2010-01-01T23:59:59.000Z

460

Synthesis, Characterization, and Ultrafast Dynamics of Metal, Metal Oxide, and Semiconductor Nanomaterials  

E-Print Network [OSTI]

cancer treatment, sensors, lasers, and solar cells. Onedetectors, solar energy conversion, sensors, and manydetectors, solar energy conversion, lasers, and sensors. A

Wheeler, Damon Andreas

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "band-gap semiconductor oxide" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

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

E-Print Network [OSTI]

energy conversion, and other high temperature applications.[1-5] Since the efficiency of those energy conversion applications relies heavily on the carrier transport properties of the materials used, it is very by Molecular Beam Epitaxy (MBE) has demonstrated its usefulness in thermoelectric energy conversion

Bowers, John

462

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

E-Print Network [OSTI]

energy conversion, and other high-temperature applications.1­4 Since the efficiency of these energy conversion applications relies heavily on the carrier transport properties of the materials used, it is very by molecular beam epitaxy (MBE) has demonstrated its useful- ness in thermoelectric energy conversion

463

Synthesis, Characterization, and Ultrafast Dynamics of Metal, Metal Oxide, and Semiconductor Nanomaterials  

E-Print Network [OSTI]

S. R. ; Cowan, A. J. ; Barroso, M. ; Sivula, K. ; Ye, J. ;3861. (167) Pendlebury, S. R. ; Barroso, M. ; Cowan, A. J. ;+. (199) Pendlebury, S. ; Barroso, M. ; Cowan, A. ; Sivula,

Wheeler, Damon Andreas

2013-01-01T23:59:59.000Z

464

Atomic scale studies of interface formation between oxides and III-V semiconductor surfaces  

E-Print Network [OSTI]

Kelvin probe microscopy in UHV conditions is an exception.TMA trimethyl aluminum UHV ultra high vacuum VASP Vienna abthe tools necessary for my UHV chamber to produce the data

Clemens, Jonathon Boyd

2010-01-01T23:59:59.000Z

465

Photoinduced electron transfer from semiconductor quantum dots to metal oxide nanoparticles  

Science Journals Connector (OSTI)

...particle and QD, respectively, e is the elementary charge, RQD and {epsilon}QD are the radius and dielectric...architectures designed to reduce grain boundary resistance (25, 46, 47). Although a full understanding of the relationship...theorem, the radial component of the electric field is D r ¼ 1 r2 Z r o x x2dx...

Kevin Tvrdy; Pavel A. Frantsuzov; Prashant V. Kamat

2011-01-01T23:59:59.000Z

466

Semiconductor nanocrystal probes for biological applications and process for making and using such probes  

DOE Patents [OSTI]

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.

Weiss, Shimon; Bruchez, Marcel; Alivisatos, Paul

2014-01-28T23:59:59.000Z

467

High-efficiency turquoise-blue electrophosphorescence from a Pt(II)-pyridyltriazolate complex in phosphine oxide host  

SciTech Connect (OSTI)

We have demonstrated high-efficiency turquoise-blue electrophosphorescence from the complex Pt(ptp)2 = bis[3,5–bis(2–pyridyl)–1,2,4–triazolato]platinum(II) doped in the wide band-gap, ambipolar phosphine oxide host HM-A1 = 4-(diphenylphosphoryl)-N,N-diphenylaniline. For devices with 5% Pt(ptp)2 doping in HM-A1, we have achieved a peak external quantum efficiency and power efficiency of (11.8 ± 0.6) % and (61.2 ± 5.9) lm/W with high-pixel values of 13.1 % and 70.6 lm/W, respectively. These parameters maintained (10.6 ± 0.2) % and (40.3 ± 1.2) lm/W at a brightness of 1000 cd/m2 with high-pixel values of 10.8 % and 41.6 lm/W. Examination of several device structures suggests that the high performance is due to improved charge transport and exciton confinement in the emissive region. Devices with 1-10% doping concentration exhibit turquoise-blue emissions (?max ~ 480 nm) with a monotonic decrease in monomer/excimer intensity ratio upon increasing the doping concentration. Devices with 5% doping exhibit sufficient blue contribution to attain white light upon combination with highly-doped or neat emissive layers of the same phosphor; the work herein represents a significant backdrop toward optimizing such white OLEDs given the performance metrics above, which to our knowledge represent the highest performance for OLEDs that exhibit blue emission maxima.

Bhansali, Unnat S.; Polikarpov, Evgueni; Swensen, James S.; Chen, Wei; Jia, Huiping; Gaspar, Daniel J.; Gnade, Bruce E.; Padmaperuma, Asanga B.; Omary, Mohammad A.

2009-12-10T23:59:59.000Z

468

A New Route to Nanoscale Conducting Channels in Insulating Oxides  

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

A New Route to Nanoscale Conducting Channels in Insulating Oxides Print A New Route to Nanoscale Conducting Channels in Insulating Oxides Print Two-dimensional electron gases (2DEGs)-narrow conducting channels at the surfaces and interfaces of semiconductor materials-are the bedrock of conventional electronics. The startling 2004 discovery that such 2DEGs could be engineered at the interface between two insulating transition-metal oxides, SrTiO3 and LaAlO3, initiated a worldwide effort to harness the functionality of oxide materials for advanced electronic applications. Now, an international collaboration working at the ALS has shown that the interface is not required. Using only intense synchrotron light, the group has been able to create and control 2DEGs at the bare surfaces of the insulating oxides SrTiO3 and KTaO3. As well as suggesting a potential methodology to spatially pattern 2DEGs in a wide variety of complex oxides, this discovery opens a new avenue for spectroscopic investigation of these novel electronic systems.

469

A New Route to Nanoscale Conducting Channels in Insulating Oxides  

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

New Route to Nanoscale Conducting Channels in Insulating Oxides Print New Route to Nanoscale Conducting Channels in Insulating Oxides Print Two-dimensional electron gases (2DEGs)-narrow conducting channels at the surfaces and interfaces of semiconductor materials-are the bedrock of conventional electronics. The startling 2004 discovery that such 2DEGs could be engineered at the interface between two insulating transition-metal oxides, SrTiO3 and LaAlO3, initiated a worldwide effort to harness the functionality of oxide materials for advanced electronic applications. Now, an international collaboration working at the ALS has shown that the interface is not required. Using only intense synchrotron light, the group has been able to create and control 2DEGs at the bare surfaces of the insulating oxides SrTiO3 and KTaO3. As well as suggesting a potential methodology to spatially pattern 2DEGs in a wide variety of complex oxides, this discovery opens a new avenue for spectroscopic investigation of these novel electronic systems.

470

A New Route to Nanoscale Conducting Channels in Insulating Oxides  

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

A New Route to Nanoscale Conducting Channels in Insulating Oxides Print A New Route to Nanoscale Conducting Channels in Insulating Oxides Print Two-dimensional electron gases (2DEGs)-narrow conducting channels at the surfaces and interfaces of semiconductor materials-are the bedrock of conventional electronics. The startling 2004 discovery that such 2DEGs could be engineered at the interface between two insulating transition-metal oxides, SrTiO3 and LaAlO3, initiated a worldwide effort to harness the functionality of oxide materials for advanced electronic applications. Now, an international collaboration working at the ALS has shown that the interface is not required. Using only intense synchrotron light, the group has been able to create and control 2DEGs at the bare surfaces of the insulating oxides SrTiO3 and KTaO3. As well as suggesting a potential methodology to spatially pattern 2DEGs in a wide variety of complex oxides, this discovery opens a new avenue for spectroscopic investigation of these novel electronic systems.

471

A New Route to Nanoscale Conducting Channels in Insulating Oxides  

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

A New Route to Nanoscale Conducting Channels in Insulating Oxides Print A New Route to Nanoscale Conducting Channels in Insulating Oxides Print Two-dimensional electron gases (2DEGs)-narrow conducting channels at the surfaces and interfaces of semiconductor materials-are the bedrock of conventional electronics. The startling 2004 discovery that such 2DEGs could be engineered at the interface between two insulating transition-metal oxides, SrTiO3 and LaAlO3, initiated a worldwide effort to harness the functionality of oxide materials for advanced electronic applications. Now, an international collaboration working at the ALS has shown that the interface is not required. Using only intense synchrotron light, the group has been able to create and control 2DEGs at the bare surfaces of the insulating oxides SrTiO3 and KTaO3. As well as suggesting a potential methodology to spatially pattern 2DEGs in a wide variety of complex oxides, this discovery opens a new avenue for spectroscopic investigation of these novel electronic systems.

472

A New Route to Nanoscale Conducting Channels in Insulating Oxides  

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

A New Route to Nanoscale Conducting Channels in Insulating Oxides Print A New Route to Nanoscale Conducting Channels in Insulating Oxides Print Two-dimensional electron gases (2DEGs)-narrow conducting channels at the surfaces and interfaces of semiconductor materials-are the bedrock of conventional electronics. The startling 2004 discovery that such 2DEGs could be engineered at the interface between two insulating transition-metal oxides, SrTiO3 and LaAlO3, initiated a worldwide effort to harness the functionality of oxide materials for advanced electronic applications. Now, an international collaboration working at the ALS has shown that the interface is not required. Using only intense synchrotron light, the group has been able to create and control 2DEGs at the bare surfaces of the insulating oxides SrTiO3 and KTaO3. As well as suggesting a potential methodology to spatially pattern 2DEGs in a wide variety of complex oxides, this discovery opens a new avenue for spectroscopic investigation of these novel electronic systems.

473

A New Route to Nanoscale Conducting Channels in Insulating Oxides  

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

A New Route to Nanoscale Conducting Channels in Insulating Oxides Print A New Route to Nanoscale Conducting Channels in Insulating Oxides Print Two-dimensional electron gases (2DEGs)-narrow conducting channels at the surfaces and interfaces of semiconductor materials-are the bedrock of conventional electronics. The startling 2004 discovery that such 2DEGs could be engineered at the interface between two insulating transition-metal oxides, SrTiO3 and LaAlO3, initiated a worldwide effort to harness the functionality of oxide materials for advanced electronic applications. Now, an international collaboration working at the ALS has shown that the interface is not required. Using only intense synchrotron light, the group has been able to create and control 2DEGs at the bare surfaces of the insulating oxides SrTiO3 and KTaO3. As well as suggesting a potential methodology to spatially pattern 2DEGs in a wide variety of complex oxides, this discovery opens a new avenue for spectroscopic investigation of these novel electronic systems.

474

A New Route to Nanoscale Conducting Channels in Insulating Oxides  

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

A New Route to Nanoscale A New Route to Nanoscale Conducting Channels in Insulating Oxides A New Route to Nanoscale Conducting Channels in Insulating Oxides Print Wednesday, 29 August 2012 00:00 Two-dimensional electron gases (2DEGs)-narrow conducting channels at the surfaces and interfaces of semiconductor materials-are the bedrock of conventional electronics. The startling 2004 discovery that such 2DEGs could be engineered at the interface between two insulating transition-metal oxides, SrTiO3 and LaAlO3, initiated a worldwide effort to harness the functionality of oxide materials for advanced electronic applications. Now, an international collaboration working at the ALS has shown that the interface is not required. Using only intense synchrotron light, the group has been able to create and control 2DEGs at the bare surfaces of the insulating oxides SrTiO3 and KTaO3. As well as suggesting a potential methodology to spatially pattern 2DEGs in a wide variety of complex oxides, this discovery opens a new avenue for spectroscopic investigation of these novel electronic systems.

475

Nano-/microstructure improved photocatalytic activities of semiconductors  

Science Journals Connector (OSTI)

...hydrothermal method [52] and micro-arc oxidation [53]). Among those preparation...special synthetic techniques, some micro-/nanostructures are being...films prepared on titanium by micro-arc oxidation. Mater. Sci. Eng. A 476...

2013-01-01T23:59:59.000Z

476

Reduction of native oxides on InAs by atomic layer deposited Al{sub 2}O{sub 3} and HfO{sub 2}  

SciTech Connect (OSTI)

Thin high-{kappa} oxide films on InAs, formed by atomic layer deposition, are the key to achieve high-speed metal-oxide-semiconductor devices. We have studied the native oxide and the interface between InAs and 2 nm thick Al{sub 2}O{sub 3} or HfO{sub 2} layers using synchrotron x-ray photoemission spectroscopy. Both films lead to a strong oxide reduction, obtaining less than 10% of the native As-oxides and between 10% and 50% of the native In-oxides, depending on the deposition temperature. The ratio of native In- to As-oxides is determined to be 2:1. The exact composition and the influence of different oxidation states and suboxides is discussed in detail.

Timm, R.; Fian, A.; Hjort, M.; Thelander, C.; Lind, E.; Andersen, J. N.; Wernersson, L.-E.; Mikkelsen, A. [Department of Physics, Nanometer Structure Consortium, Lund University, P.O. Box 118, 22 100 Lund (Sweden)

2010-09-27T23:59:59.000Z

477

EXAFS and XANES analysis of oxides at the nanoscale  

Science Journals Connector (OSTI)

This work presents a discussion of the possibilities offered by X-ray absorption spectroscopy (XAS) to study the local structure of nanomaterials. The current state of the art for the interpretation of extended X-ray absorption fine structure (EXAFS), including an advanced approach based on the use of classical molecular dynamics, is described and exemplified in the case of NiO nanoparticles. In addition, the limits and possibilities of X-ray absorption near-edge spectroscopy (XANES) in determining several effects associated with the nanocrystalline nature of materials are also discussed in connection with the development of ZnO-based dilute magnetic semiconductors and iron oxide nanoparticles.

Kuzmin, A.

2014-10-31T23:59:59.000Z

478

Oxidation of propylene over copper oxide catalysts  

E-Print Network [OSTI]

to the study of propylene oxidation. Dunlop (17) reported that small quantities of iron compounds substantially enhanced the catalytic activity of chromia-alumina catalysts with respect to propylene oxidation, Woodharn (72) has suggested that under... between 360 C and 430oC the rate of propane oxidation decreases as the teznperature is increased, and the rate of conversion to olefins, especially propylene, becomes progressively greater. Above 430 C the proportion of propane converted to ethylene in...

Billingsley, David Stuart

2012-06-07T23:59:59.000Z

479

Alternative Gate Dielectrics on Semiconductors for MOSFET Device Applications  

SciTech Connect (OSTI)

We have investigated the synthesis and properties of deposited oxides on Si and Ge for use as alternative gate dielectrics in MOSFET applications. The capacitance and leakage current behavior of polycrystalline Y{sub 2}O{sub 3} films synthesized by pulsed-laser deposition is reported. In addition, we also discuss the growth of epitaxial oxide structures. In particular, we have investigated the use of silicide termination for oxide growth on (001) Si using laser-molecular beam epitaxy. In addition, we discuss a novel approach involving the use of hydrogen to eliminate native oxide during initial dielectric oxide nucleation on (001) Ge.

Norton, D.P.; Budai, J.D.; Chisholm, M.F.; Pennycook, S.J.; McKee, R.; Walker, F.; Lee, Y.; Park, C.

1999-12-06T23:59:59.000Z

480

Domain formation on oxidized graphene  

Science Journals Connector (OSTI)

Using first-principles calculations within density functional theory, we demonstrate that the adsorption of a single oxygen atom results in significant electron transfer from graphene to oxygen. This strongly disturbs the charge landscape of the C-C bonds at the proximity. Additional oxygen atoms adsorbing to graphene prefer always the C-C bonds having the highest charge density and, consequently, they have the tendency to form domain structure. While oxygen adsorption to one side of graphene ends with significant buckling, the adsorption to both sides with similar domain pattern is favored. The binding energy displays an oscillatory variation and the band gap widens with increasing oxygen coverage. While a single oxygen atom migrates over the C-C bonds on the graphene surface, a repulsive interaction prevents two oxygen adatoms from forming an oxygen molecule. Our first-principles study together with finite-temperature ab initio molecular dynamics calculations conclude that oxygen adatoms on graphene can not desorb easily without the influence of external agents.

M. Topsakal and S. Ciraci

2012-11-01T23:59:59.000Z

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481

Operation and performance of the ATLAS semiconductor tracker  

E-Print Network [OSTI]

The semiconductor tracker is a silicon microstrip detector forming part of the inner tracking system of the ATLAS experiment at the LHC. The operation and performance of the semiconductor tracker during the first years of LHC running are described. More than 99% of the detector modules were operational during this period, with an average intrinsic hit efficiency of (99.74 +/- 0.04)%. The evolution of the noise occupancy is discussed, and measurements of the Lorentz angle, delta-ray production and energy loss presented. The alignment of the detector is found to be stable at the few-micron level over long periods of time. Radiation damage measurements, which include the evolution of detector leakage currents, are found to be consistent with predictions and are used in the verification of radiation background simulations.

Aad, Georges; Abdallah, Jalal; Abdel Khalek, Samah; Abdinov, Ovsat; Aben, Rosemarie; Abi, Babak; Abolins, Maris; AbouZeid, Ossama; Abramowicz, Halina; Abreu, Henso; Abreu, Ricardo; Abulaiti, Yiming; Acharya, Bobby Samir; Adamczyk, Leszek; Adams, David; Adelman, Jahred; Adomeit, Stefanie; Adye, Tim; Agatonovic-Jovin, Tatjana; Aguilar-Saavedra, Juan Antonio; Agustoni, Marco; Ahlen, Steven; Ahmad, Ashfaq; Ahmadov, Faig; Aielli, Giulio; Åkesson, Torsten Paul Ake; Akimoto, Ginga; Akimov, Andrei; Alberghi, Gian Luigi; Albert, Justin; Albrand, Solveig; Alconada Verzini, Maria Josefina; Aleksa, Martin; Aleksandrov, Igor; Alexa, Calin; Alexander, Gideon; Alexandre, Gauthier; Alexopoulos, Theodoros; Alhroob, Muhammad; Alimonti, Gianluca; Alio, Lion; Alison, John; Allbrooke, Benedict; Allison, Lee John; Allport, Phillip; Allwood-Spiers, Sarah; Almond, John; Aloisio, Alberto; Alonso, Alejandro; Alonso, Francisco; Alpigiani, Cristiano; Altheimer, Andrew David; Alvarez Gonzalez, Barbara; Alviggi, Mariagrazia; Amako, Katsuya; Amaral Coutinho, Yara; Amelung, Christoph; Amidei, Dante; Amor Dos Santos, Susana Patricia; Amorim, Antonio; Amoroso, Simone; Amram, Nir; Amundsen, Glenn; Anastopoulos, Christos; Ancu, Lucian Stefan; Andari, Nansi; Andeen, Timothy; Anders, Christoph Falk; Anders, Gabriel; Anderson, Kelby; Andreazza, Attilio; Andrei, George Victor; Anduaga, Xabier; Angelidakis, Stylianos; Angelozzi, Ivan; Anger, Philipp; Angerami, Aaron; Anghinolfi, Francis; Anisenkov, Alexey; Anjos, Nuno; Annovi, Alberto; Antonaki, Ariadni; Antonelli, Mario; Antonov, Alexey; Antos, Jaroslav; Anulli, Fabio; Aoki, Masato; Aperio Bella, Ludovica; Apolle, Rudi; Arabidze, Giorgi; Aracena, Ignacio; Arai, Yasuo; Araque, Juan Pedro; Arce, Ayana; Arguin, Jean-Francois; Argyropoulos, Spyridon; Arik, Metin; Armbruster, Aaron James; Arnaez, Olivier; Arnal, Vanessa; Arnold, Hannah; Arslan, Ozan; Artamonov, Andrei; Artoni, Giacomo; Asai, Shoji; Asbah, Nedaa; Ashkenazi, Adi; Ask, Stefan; Åsman, Barbro; Asquith, Lily; Assamagan, Ketevi; Astalos, Robert; Atkinson, Markus; Atlay, Naim Bora; Auerbach, Benjamin; Augsten, Kamil; Aurousseau, Mathieu; Avolio, Giuseppe; Azuelos, Georges; Azuma, Yuya; Baak, Max; Bacci, Cesare; Bachacou, Henri; Bachas, Konstantinos; Backes, Moritz; Backhaus, Malte; Backus Mayes, John; Badescu, Elisabeta; Bagiacchi, Paolo; Bagnaia, Paolo; Bai, Yu; Bain, Travis; Baines, John; Baker, Oliver Keith; Baker, Sarah; Balek, Petr; Balli, Fabrice; Banas, Elzbieta; Banerjee, Swagato; Banfi, Danilo; Bangert, Andrea Michelle; Bannoura, Arwa A E; Bansal, Vikas; Bansil, Hardeep Singh; Barak, Liron; Baranov, Sergei; Barberio, Elisabetta Luigia; Barberis, Dario; Barbero, Marlon; Barillari, Teresa; Barisonzi, Marcello; Barklow, Timothy; Barlow, Nick; Barnett, Bruce; Barnett, Michael; Barnovska, Zuzana; Baroncelli, Antonio; Barone, Gaetano; Barr, Alan; Barreiro, Fernando; Barreiro Guimarães da Costa, João; Bartoldus, Rainer; Barton, Adam Edward; Bartos, Pavol; Bartsch, Valeria; Bassalat, Ahmed; Basye, Austin; Bates, Richard; Batkova, Lucia; Batley, Richard; Battistin, Michele; Bauer, Florian; Bawa, Harinder Singh; Beau, Tristan; Beauchemin, Pierre-Hugues; Beccherle, Roberto; Bechtle, Philip; Beck, Hans Peter; Becker, Anne Kathrin; Becker, Sebastian; Beckingham, Matthew; Becot, Cyril; Beddall, Andrew; Beddall, Ayda; Bedikian, Sourpouhi; Bednyakov, Vadim; Bee, Christopher; Beemster, Lars; Beermann, Thomas; Begel, Michael; Behr, Katharina; Belanger-Champagne, Camille; Bell, Paul; Bell, William; Bella, Gideon; Bellagamba, Lorenzo; Bellerive, Alain; Bellomo, Massimiliano; Belloni, Alberto; Belotskiy, Konstantin; Beltramello, Olga; Benary, Odette; Benchekroun, Driss; Bendtz, Katarina; Benekos, Nektarios; Benhammou, Yan; Benhar Noccioli, Eleonora; Benitez Garcia, Jorge-Armando; Benjamin, Douglas; Bensinger, James; Benslama, Kamal; Bentvelsen, Stan; Berge, David; Bergeaas Kuutmann, Elin; Berger, Nicolas; Berghaus, Frank; Berglund, Elina; Beringer, Jürg; Bernabéu, José; Bernard, Clare; Bernat, Pauline; Bernius, Catrin; Bernlochner, Florian Urs; Berry, Tracey; Berta, Peter; Bertella, Claudia; Bertolucci, Federico; Besana, Maria Ilaria; Besjes, Geert-Jan; Bessidskaia, Olga; Besson, Nathalie; Betancourt, Christopher; Bethke, Siegfried; Bhimji, Wahid; Bianchi, Riccardo-Maria; Bianchini, Louis; Bianco, Michele; Biebel, Otmar; Bieniek, Stephen Paul; Bierwagen, Katharina; Biesiada, Jed; Biglietti, Michela; Bilbao De Mendizabal, Javier; Bilokon, Halina; Bindi, Marcello; Binet, Sebastien; Bingul, Ahmet; Bini, Cesare; Black, Curtis; Black, James; Black, Kevin

2014-01-01T23:59:59.000Z

482

Operation and performance of the ATLAS semiconductor tracker  

E-Print Network [OSTI]

The semiconductor tracker is a silicon microstrip detector forming part of the inner tracking system of the ATLAS experiment at the LHC. The operation and performance of the semiconductor tracker during the first years of LHC running are described. More than 99% of the detector modules were operational during this period, with an average intrinsic hit efficiency of (99.74 +/- 0.04)%. The evolution of the noise occupancy is discussed, and measurements of the Lorentz angle, delta-ray production and energy loss presented. The alignment of the detector is found to be stable at the few-micron level over long periods of time. Radiation damage measurements, which include the evolution of detector leakage currents, are found to be consistent with predictions and are used in the verification of radiation background simulations.

ATLAS Collaboration

2014-04-29T23:59:59.000Z

483

Semiconductor laser devices having lateral refractive index tailoring  

DOE Patents [OSTI]

A broad-area semiconductor laser diode includes an active lasing region interposed between an upper and a lower cladding layer, the laser diode further comprising structure for controllably varying a lateral refractive index profile of the diode to substantially compensate for an effect of junction heating during operation. In embodiments disclosed the controlling structure comprises resistive heating strips or non-radiative linear junctions disposed parallel to the active region. Another embodiment discloses a multi-layered upper cladding region selectively disordered by implanted or diffused dopant impurities. Still another embodiment discloses an upper cladding layer of variable thickness that is convex in shape and symmetrically disposed about a central axis of the active region. The teaching of the invention is also shown to be applicable to arrays of semiconductor laser diodes.

Ashby, Carol I. H. (Edgewood, NM); Hadley, G. Ronald (Alburquerque, NM); Hohimer, John P. (Albuquerque, NM); Owyoung, Adelbert (Albuquerque, NM)

1990-01-01T23:59:59.000Z

484

Hybrid high-temperature superconductor-semiconductor tunnel diode  

E-Print Network [OSTI]

We report the demonstration of hybrid high-Tc-superconductor-semiconductor tunnel junctions, enabling new interdisciplinary directions in condensed matter research. The devices were fabricated by our newly-developed mechanical bonding technique, resulting in high-Tc-semiconductor planar junctions acting as superconducting tunnel diodes. Tunneling-spectra characterization of the hybrid junctions of Bi2Sr2CaCu2O8+{\\delta} combined with bulk GaAs, or a GaAs/AlGaAs quantum well, exhibits excess voltage and nonlinearity - in good agreement with theoretical predictions for a d-wave superconductor-normal material junction, and similar to spectra obtained in scanning tunneling microscopy. Additional junctions are demonstrated using Bi2Sr2CaCu2O8+{\\delta} combined with graphite or Bi2Te3. Our results pave the way for new methods in unconventional superconductivity studies, novel materials and quantum technology applications.

Alex Hayat; Parisa Zareapour; Shu Yang F. Zhao; Achint Jain; Igor G. Savelyev; Marina Blumin; Zhijun Xu; Alina Yang; G. D. Gu; Harry E. Ruda; Shuang Jia; R. J. Cava; Aephraim M. Steinberg; Kenneth S. Burch

2013-01-09T23:59:59.000Z

485

Hybrid High-Temperature-Superconductor–Semiconductor Tunnel Diode  

Science Journals Connector (OSTI)

We report the demonstration of hybrid high-Tc-superconductor–semiconductor tunnel junctions, enabling new interdisciplinary directions in condensed matter research. The devices are fabricated by our newly developed mechanical-bonding technique, resulting in high-Tc-superconductor–semiconductor tunnel diodes. Tunneling-spectra characterization of the hybrid junctions of Bi2Sr2CaCu2O8+? combined with bulk GaAs, or a GaAs/AlGaAs quantum well, exhibits excess voltage and nonlinearity, similarly to spectra obtained in scanning-tunneling microscopy, and is in good agreement with theoretical predictions for a d-wave-superconductor–normal-material junction. Additional junctions are demonstrated using Bi2Sr2CaCu2O8+? combined with graphite or Bi2Te3. Our results pave the way for new methods in unconventional superconductivity studies, novel materials, and quantum technology applications.

Alex Hayat; Parisa Zareapour; Shu Yang F. Zhao; Achint Jain; Igor G. Savelyev; Marina Blumin; Zhijun Xu; Alina Yang; G. D. Gu; Harry E. Ruda; Shuang Jia; R. J. Cava; Aephraim M. Steinberg; Kenneth S. Burch

2012-12-27T23:59:59.000Z

486

First-principles simulations of exciton diffusion in organic semiconductors  

Science Journals Connector (OSTI)

Exciton diffusion is crucial for the performance of organic semiconductors in photovoltaic and solid state lighting applications. We propose a first-principles approach that can predict exciton dynamics in organic semiconductors. The method is based on time-dependent density functional theory to describe the energy and many-body wave functions of excitons. Nonadiabatic ab initio molecular dynamics is used to calculate phonon-assisted transition rates between localized exciton states. Using Monte Carlo simulations, we determine the exciton diffusion length, lifetime, diffusivity, and harvesting efficiency in poly(3-hexylthiophene) polymers at different temperatures, which agree very well with the experiments. We find that exciton diffusion is primarily determined by the density of states of low-energy excitons. A widely speculated diffusion mechanism, namely an initial downhill migration followed by thermally activated migration, is confirmed and elucidated by the simulations. Some general guidelines for designing more efficient organic solar cells are obtained from the simulations.

Xu Zhang; Zi Li; Gang Lu

2011-12-22T23:59:59.000Z

487

Semiconductor Nanocrystals-Based White Light Emitting Diodes  

SciTech Connect (OSTI)

In response to the demands for energy and the concerns of global warming and climate change, energy efficient and environmentally friendly solid state lighting, such as white light emitting diodes (WLEDs), is considered to be the most promising and suitable light source. Because of their small size, high efficiency, and long lifetime, WLEDs based on colloidal semiconductor nanocrystals (or quantum dots) are emerging as a completely new technology platform for the development of flat-panel displays and solid state lighting, exhibiting the potential to replace the conventionally used incandescent and fluorescent lamps. This replacement could cut the ever-increasing energy consumption, solve the problem of rapidly depleting fossil fuel reserves, and improve the quality of the global environment. In this review, we highlight the recent progress in semiconductor nanocrystals-based WLEDs, compare different approaches for generating white light, and discuss the benefits and challenges of the solid state lighting technology.

Dai, Quanqin [ORNL; Hu, Michael Z. [ORNL; Duty, Chad E [ORNL

2010-01-01T23:59:59.000Z

488

Semiconductor-Nanocrystals-Based White Light-Emitting Diodes  

SciTech Connect (OSTI)

In response to the demands for energy and the concerns of global warming and climate change, energy efficient and environmentally friendly solid-state lighting, such as white lightemitting diodes (WLEDs), is considered to be the most promising and suitable light source. Because of their small size, high efficiency, and long lifetime, WLEDs based on colloidal semiconductor nanocrystals (or quantum dots) are emerging as a completely new technology platform for the development of flat-panel displays and solid-state lighting, exhibiting the potential to replace the conventionally used incandescent and fluorescent lamps. This replacement can cut the ever-increasing level of energy consumption, solve the problem of rapidly depleting fossil fuel reserves, and improve the quality of the global environment. In this review, the recent progress in semiconductor-nanocrystals-based WLEDs is highlighted, the different approaches for generating white light are compared, and the benefits and challenges of the solid-state lighting technology are discussed.

Dai, Quanqin [ORNL; Duty, Chad E [ORNL; Hu, Michael Z. [ORNL

2010-01-01T23:59:59.000Z

489

Neutron detection using boron gallium nitride semiconductor material  

SciTech Connect (OSTI)

In this study, we developed a new neutron-detection device using a boron gallium nitride (BGaN) semiconductor in which the B atom acts as a neutron converter. BGaN and gallium nitride (GaN) samples were grown by metal organic vapor phase epitaxy, and their radiation detection properties were evaluated. GaN exhibited good sensitivity to ?-rays but poor sensitivity to ?-rays. Moreover, we confirmed that electrons were generated in the depletion layer under neutron irradiation. This resulted in a neutron-detection signal after ?-rays were generated by the capture of neutrons by the B atoms. These results prove that BGaN is useful as a neutron-detecting semiconductor material.

Atsumi, Katsuhiro [Department of Electrical and Electronic Engineering, Graduate School of Engineering, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8561 (Japan); Inoue, Yoku; Nakano, Takayuki, E-mail: ttnakan@ipc.shizuoka.ac.jp [Department of Electrical and Materials Science, Graduate School of Engineering, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8561 (Japan); Mimura, Hidenori; Aoki, Toru [Research Institute of Electronics, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8011 (Japan)

2014-03-01T23:59:59.000Z

490

Method for measuring the drift mobility in doped semiconductors  

DOE Patents [OSTI]

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.

Crandall, R.S.

1982-03-09T23:59:59.000Z

491

Imaging of semiconductors using a flying laser spot scanning system  

E-Print Network [OSTI]

be obsezved in the wavelength vs. absorption coefficient curves shown in Figure 1 for both a direct and an indirect semiconductor material (gallium-arsenide and silicon). It is only in the direct absorption and subsequent generation of a hole electron pair... in wavelength of light used to generate carriers pro- vides some contzol over the depth of the material analyzed. Long wavelength energy (- 1 micrometer) penetrates deeply into silicon, while gallium phosphide is considered almost transparent for a typical...

Richardson, Thomas William

2012-06-07T23:59:59.000Z

492

Contacts Between Metals and Between a Metal and a Semiconductor  

Science Journals Connector (OSTI)

The problem of contacts between metals and between a metal and a semiconductor is treated classically with the help of the results of wave mechanical theory of electron energy states in solids. The potential and electron density distributions in the two bodies near the contact are discussed. The bodies are assumed to be in immediate contact. The problem of a body in vacuum and the problem of two bodies separated by a gap are discussed qualitatively.

H. Y. Fan

1942-10-01T23:59:59.000Z

493

Electronic Structure and Magnetism in Diluted Magnetic Semiconductors  

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

Electronic Structure and Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print Wednesday, 29 November 2006 00:00 The possibility of using electrons' spins in addition to their charge in information technology has created much enthusiasm for a new field of electronics popularly known as "spintronics." An intensely studied approach to obtaining spin-polarized carriers for data-storage devices is the use of diluted magnetic semiconductors created by doping ions like Mn, Fe, or Co having a net spin into a semiconducting host such as GaAs, ZnO, or GaN. The interaction among these spins leads to ferromagnetic order at low temperatures, which is necessary to create spin-polarized carriers. A research team working at ALS Beamline 4.0.2 and European Synchrotron Radiation Facility Beamline ID8 made a big leap forward in clarifying the microscopic picture of magnetism and anisotropy in Mn-doped GaAs by resolving localized and hybridized d states using angle-dependent x-ray magnetic circular dichroism (XMCD) measurements.