Sample records for materials semiconductor organic

  1. Theory of Organic Magnetoresistance in Disordered Organic Semiconductors

    E-Print Network [OSTI]

    Flatte, Michael E.

    Theory of Organic Magnetoresistance in Disordered Organic Semiconductors Nicholas J. Harmon semiconductors, disordered semiconductors, organic magnetoresistance, percolation theory, spin transport organic semiconductors. The theory proposed here maps the complex phenomena of spin-dependent hopping onto

  2. High-Throughput Transfer Imprinting for Organic Semiconductors

    E-Print Network [OSTI]

    Choo, Gihoon

    2013-08-06T23:59:59.000Z

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

  3. Charge-carrier transport in amorphous organic semiconductors

    E-Print Network [OSTI]

    Limketkai, Benjie, 1982-

    2008-01-01T23:59:59.000Z

    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 ...

  4. Spin injection and manipulation in organic semiconductors

    E-Print Network [OSTI]

    Venkataraman, Karthik (Karthik Raman)

    2011-01-01T23:59:59.000Z

    The use of organic semiconductors to enable organic spintronic devices requires the understanding of transport and control of the spin state of the carriers. This thesis deals with the above issue, focusing on the interface ...

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

    E-Print Network [OSTI]

    Steckel, Jonathan S. (Jonathan Stephen)

    2006-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

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

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

    DOE Patents [OSTI]

    Sopori, Bhushan; Rangappan, Anikara

    2014-11-25T23:59:59.000Z

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

  8. Electroluminescence in ion gel gated organic polymer semiconductor transistors

    E-Print Network [OSTI]

    Bhat, Shrivalli

    2011-07-12T23:59:59.000Z

    This thesis reports the light emission in ion gel gated, thin film organic semiconductor transistors and investigates the light emission mechanism behind these devices. We report that ion gel gated organic polymer semiconductor transistors emit...

  9. Method of doping organic semiconductors

    DOE Patents [OSTI]

    Kloc,; Christian Leo (Constance, DE); Ramirez; Arthur Penn (Summit, NJ); So, Woo-Young (New Providence, NJ)

    2010-10-26T23:59:59.000Z

    An apparatus has a crystalline organic semiconducting region that includes polyaromatic molecules. A source electrode and a drain electrode of a field-effect transistor are both in contact with the crystalline organic semiconducting region. A gate electrode of the field-effect transistor is located to affect the conductivity of the crystalline organic semiconducting region between the source and drain electrodes. A dielectric layer of a first dielectric that is substantially impermeable to oxygen is in contact with the crystalline organic semiconducting region. The crystalline organic semiconducting region is located between the dielectric layer and a substrate. The gate electrode is located on the dielectric layer. A portion of the crystalline organic semiconducting region is in contact with a second dielectric via an opening in the dielectric layer. A physical interface is located between the second dielectric and the first dielectric.

  10. Seebeck coefficient in organic semiconductors

    E-Print Network [OSTI]

    Venkateshvaran, Deepak

    2014-07-01T23:59:59.000Z

    of this PhD thesis lie in building cost-effective and environmentally friendly waste-heat to useful energy converters based on organic polymers. The efficiency of heat to energy conversion by organic polymers tends to be higher than that for conventional...

  11. Method of doping organic semiconductors

    DOE Patents [OSTI]

    Kloc, Christian Leo (Constance, DE); Ramirez, Arthur Penn (Summit, NJ); So, Woo-Young (New Providence, NJ)

    2012-02-28T23:59:59.000Z

    A method includes the steps of forming a contiguous semiconducting region and heating the region. The semiconducting region includes polyaromatic molecules. The heating raises the semiconducting region to a temperature above room temperature. The heating is performed in the presence of a dopant gas and the absence of light to form a doped organic semiconducting region.

  12. Semiconductor bridge, SCB, ignition of energetic materials

    SciTech Connect (OSTI)

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

    1997-04-01T23:59:59.000Z

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

  13. Exploring Electron Transfer in Organic Semiconductors | MIT-Harvard...

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

    Electron Transfer in Organic Semiconductors January 28, 2009 at 3pm36-428 Troy Van Voorhis Department of Chemistry, Massachusetts Institute of Technology vanvoorhis2000 abstract:...

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

    SciTech Connect (OSTI)

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

    1998-11-01T23:59:59.000Z

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

  15. Room temperature triplet state spectroscopy of organic semiconductors

    E-Print Network [OSTI]

    Reineke, Sebastian

    2013-01-01T23:59:59.000Z

    Organic light emitting devices and solar cells are machines that create, manipulate and destroy excited states in organic semiconductors. It is crucial to characterize these excited states, or excitons, to optimize device performance in applications like displays and solar energy harvesting. This is complicated if the excited state is a triplet because the electronic transition is dark with a vanishing oscillator strength. As a consequence, triplet state spectroscopy must usually be performed at cryogenic temperatures to reduce competition from non-radiative rates. Here, we control non-radiative rates by engineering a solid-state host matrix containing the target molecule, allowing the observation of phosphorescence at room temperature and alleviating constraints of cryogenic experiments. We test these techniques on a wide range of materials with functionalities spanning multi-exciton generation (singlet exciton fission), organic light emitting device host materials, and thermally activated delayed fluorescen...

  16. Method for depositing high-quality microcrystalline semiconductor materials

    DOE Patents [OSTI]

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

    2011-03-08T23:59:59.000Z

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

  17. Method of preparing nitrogen containing semiconductor material

    DOE Patents [OSTI]

    Barber, Greg D.; Kurtz, Sarah R.

    2004-09-07T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

    Zhu, Xiaoyang

    2014-12-10T23:59:59.000Z

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

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

    DOE Patents [OSTI]

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

    1985-10-11T23:59:59.000Z

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

  20. High-Throughput Transfer Imprinting for Organic Semiconductors 

    E-Print Network [OSTI]

    Choo, Gihoon

    2013-08-06T23:59:59.000Z

    . In this work, nanoimprint-based transfer imprinting of organic semiconductor is studied. In the same time the suggested technique is simulated with COMSOL multi-physics simulator to understand its mechanism. This transfer printing technique utilize thermal...

  1. Optically Detected Magnetic Resonance and Thermal Activation Spectroscopy Study of Organic Semiconductors

    SciTech Connect (OSTI)

    Chang-Hwan Kim

    2003-12-12T23:59:59.000Z

    Organic electronic materials are a new class of emerging materials. Organic light emitting devices (OLEDs) are the most promising candidates for future flat panel display technologies. The photophysical characterization is the basic research step one must follow to understand this new class of materials and devices. The light emission properties are closely related to the transport properties of these materials. The objective of this dissertation is to probe the relation between transport and photophysical properties of organic semiconductors. The transport characteristics were evaluated by using thermally stimulated current and thermally stimulated luminescence techniques. The photoluminescence detected magnetic resonance and photoluminescence quantum yield studies provide valuable photophysical information on this class of materials. OLEDs are already in the market. However, detailed studies on the degradation mechanisms are still lacking. Since both optically detected magnetic resonance and thermal activation spectroscopy probe long-lived defect-related states in organic semiconductors, the combined study generates new insight on the OLED operation and degradation mechanisms.

  2. Organic conductive films for semiconductor electrodes

    DOE Patents [OSTI]

    Frank, A.J.

    1984-01-01T23:59:59.000Z

    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.

  3. Synthetic Control of Organic Semiconductor Excited States

    E-Print Network [OSTI]

    Clem, Tabitha Ann

    2010-01-01T23:59:59.000Z

    Molecules for Organic Photovoltaics Abstract The synthesis,with a particular focus on photovoltaics. The first chapterfor Organic Photovoltaics Chapter 3: Cyclometalated Platinum

  4. Chemistry of Organic Electronic Materials 6483-Fall

    E-Print Network [OSTI]

    Sherrill, David

    Chemistry of Organic Electronic Materials 6483- Fall Tuesdays organic materials. The discussion will include aspects of synthesis General introduction to the electronic structure of organic materials with connection

  5. Wafer Fusion for Integration of Semiconductor Materials and Devices

    SciTech Connect (OSTI)

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

    1999-05-01T23:59:59.000Z

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

  6. Measurement of molecular motion in organic semiconductors by thermal diffuse electron scattering

    E-Print Network [OSTI]

    Eggeman, Alexander S; Illig, Steffen; Troisi, Alessandro; Sirringhaus, Henning; Midgley, Paul A

    2013-07-28T23:59:59.000Z

    in localisation of the charge carriers (3). Recently, it has been reported that this dynamic disorder model provides a consistent framework for understanding the electrical and optical properties of charge carriers in crystalline, high mobility molecular... The final version of this article can be accessed at: Nature Materials 12, 1045-1049 (2013) http://www.nature.com/doifinder/10.1038/nmat3710 1 Title: Direct Measurement of Molecular Motion in Organic Semiconductors Authors: Alexander S. Eggeman,1...

  7. Photocatalytic Oxidation of Aqueous Organic Contaminants by Semiconductors using Visible Light Radiation

    E-Print Network [OSTI]

    Meyers, Steven D.

    Photocatalytic Oxidation of Aqueous Organic Contaminants by Semiconductors using Visible Light semiconductor, InVO4, mechanically alloyed to TiO2, to shift photo-initiation into the visible range. 3, the ratio of semiconductors had no significant impact on the reaction rate. Long term goal - develop

  8. Physical properties and design of light-emitting devices based on organic materials and nanoparticles

    E-Print Network [OSTI]

    Anikeeva, Polina Olegovna

    2009-01-01T23:59:59.000Z

    This thesis presents the detailed experimental and theoretical characterization of light-emitting devices (LEDs) based on organic semiconductors and colloidal quantum dots (QDs). This hybrid material system has several ...

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

    DOE Patents [OSTI]

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

    1998-05-26T23:59:59.000Z

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

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

    DOE Patents [OSTI]

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

    1998-01-01T23:59:59.000Z

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

  11. Electrical bistability and spin valve effect in a ferromagnet/organic semiconductor/ferromagnet heterojunction

    E-Print Network [OSTI]

    Eom, Chang Beom

    Letter Electrical bistability and spin valve effect in a ferromagnet/organic semiconductor online 2 April 2010 Keywords: Bistable device Spin valve Organic semiconductor Magnetoresistance a b s t r a c t We report a study of the electrical bistability and bias-controlled spin valve effect

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

    DOE Patents [OSTI]

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

    2007-04-27T23:59:59.000Z

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

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

    DOE Patents [OSTI]

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

    1995-01-01T23:59:59.000Z

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

  14. Apparatus for measuring minority carrier lifetimes in semiconductor materials

    DOE Patents [OSTI]

    Ahrenkiel, Richard K. (Lakewood, CO)

    1999-01-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

    None

    2009-12-11T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    2014-04-15T23:59:59.000Z

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

  17. Electronic Properties of Disordered Organic Semiconductors via QM/MM Simulations

    E-Print Network [OSTI]

    Difley, Seth

    Organic semiconductors (OSCs) have recently received significant attention for their potential use in photovoltaic, light emitting diode, and field effect transistor devices. Part of the appeal of OSCs is the disordered, ...

  18. Laboratory Thin-Film Encapsulation of Air-Sensitive Organic Semiconductor Devices

    E-Print Network [OSTI]

    Subbarao, Samuel P.

    We present an approach, which is compatible with both glass and polymer substrates, to in-laboratory handling and intra-laboratory shipping of air-sensitive organic semiconductors. Encapsulation approaches are presented ...

  19. Singlet exciton fission, a multi-exciton generation process, in organic semiconductor solar cells

    E-Print Network [OSTI]

    Jadhav, Priyadarshani

    2012-01-01T23:59:59.000Z

    Organic semiconductor photovoltaics hold the promise of cheap production and low manufacturing setup costs. The highest efficiency seen in research labs, ~10% today, is still too low for production. In this work we explore ...

  20. Isotopically controlled semiconductors

    E-Print Network [OSTI]

    Haller, Eugene E.

    2001-01-01T23:59:59.000Z

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

  1. Apparatus for measuring minority carrier lifetimes in semiconductor materials

    DOE Patents [OSTI]

    Ahrenkiel, R.K.

    1999-07-27T23:59:59.000Z

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

  2. Elastomeric organic material for switching application

    SciTech Connect (OSTI)

    Shiju, K., E-mail: shijuvenus@gmail.com, E-mail: pravymon@gmail.com, E-mail: ppredeep@gmail.com; Praveen, T., E-mail: shijuvenus@gmail.com, E-mail: pravymon@gmail.com, E-mail: ppredeep@gmail.com; Preedep, P., E-mail: shijuvenus@gmail.com, E-mail: pravymon@gmail.com, E-mail: ppredeep@gmail.com [Laboratory for Molecular Photonics and Electronics (LAMP), Department of Physics, National Institute of Technology, Calicut, Kerala, 673601 (India)

    2014-10-15T23:59:59.000Z

    Organic Electronic devices like OLED, Organic Solar Cells etc are promising as, cost effective alternatives to their inorganic counterparts due to various reasons. However the organic semiconductors currently available are not attractive with respect to their high cost and intricate synthesis protocols. Here we demonstrate that Natural Rubber has the potential to become a cost effective solution to this. Here an attempt has been made to fabricate iodine doped poly isoprene based switching device. In this work Poly methyl methacrylate is used as dielectric layer and Aluminium are employed as electrodes.

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

    DOE Patents [OSTI]

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

    2011-12-06T23:59:59.000Z

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

  4. Mismatched semiconductor nanowires: growth and characterization

    E-Print Network [OSTI]

    Yim, Joanne Wing Lan

    2011-01-01T23:59:59.000Z

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

  5. Spectroscopy of Charge Carriers and Traps in Field-Doped Organic Semiconductors

    SciTech Connect (OSTI)

    Zhu, Xiaoyang; Frisbie, C Daniel

    2012-08-13T23:59:59.000Z

    This research project aims to achieve quantitative and molecular level understanding of charge carriers and traps in field-doped organic semiconductors via in situ optical absorption spectroscopy, in conjunction with time-resolved electrical measurements. During the funding period, we have made major progress in three general areas: (1) probed charge injection at the interface between a polymeric semiconductor and a polymer electrolyte dielectric and developed a thermodynamic model to quantitatively describe the transition from electrostatic to electrochemical doping; (2) developed vibrational Stark effect to probe electric field at buried organic semiconductor interfaces; (3) used displacement current measurement (DCM) to study charge transport at organic/dielectric interfaces and charge injection at metal/organic interfaces.

  6. Porous Materials -Metal-Organic Frameworks

    E-Print Network [OSTI]

    Tsymbal, Evgeny Y.

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

  7. Electronic coupling in organic-inorganic semiconductor hybrid structures with type-II energy level alignment

    E-Print Network [OSTI]

    Peters, Achim

    Electronic coupling in organic-inorganic semiconductor hybrid structures with type-II energy level Electronic coupling in a hybrid structure made of ZnMgO and a spirobifluorene derivative SP6 is inves- tigated in the situation where the energy level alignment at the organic/inorganic interface revealed

  8. Sandia National Laboratories: organic PV materials

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

    organic PV materials Sandians Win 'Best Paper' Award at Photovoltaic Conference in Japan On March 4, 2015, in Computational Modeling & Simulation, Energy, Facilities, News, News &...

  9. Strain-induced vertical self-organization of semiconductor quantum dots: A computational study

    SciTech Connect (OSTI)

    Shtinkov, N., E-mail: nshtinkov@uottawa.ca [Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa (Ontario) K1N 6N5 (Canada)

    2013-12-28T23:59:59.000Z

    Atomistic strain simulations based on the valence force field method are employed to study the vertical arrangements of semiconductor quantum dot (QD) multilayers. The effects of the QD shape, dimensions, and materials parameters are systematically investigated, varying independently the following parameters: spacer width H, QD lateral spacing D, base b, and height h, slope of the side facets, elastic properties of the dot and the substrate materials, and lattice mismatch between the dot and the substrate. The transition between vertically aligned and anti-aligned structures is found to be determined mainly by the ratios H/D and b/D, as well as by the strain anisotropy of the substrate and to a lesser extent of the QD. The dependence on the QD height h is significant only for steep side facets and large aspect ratios h/b, and the effects of the lattice mismatch strain and the bulk elastic moduli are found to be negligible. The comparison with experimental data shows an excellent agreement with the results from the simulations, demonstrating that the presented analysis results in precise theoretical predictions for the vertical self-organization regime in a wide range of QD materials systems.

  10. Rational Design and Preparation of Organic Semiconductors for use in Field Effect Transistors and Photovoltaic Cells

    E-Print Network [OSTI]

    Mauldin, Clayton Edward

    2010-01-01T23:59:59.000Z

    Distyryl Oligothiophene Semiconductors Abstract We describebonded Oligothiophene Semiconductor Side Chains Abstract Ato assemble oligothiophene semiconductors and control their

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

    E-Print Network [OSTI]

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

  12. Apparatus and method for oxidizing organic materials

    DOE Patents [OSTI]

    Surma, J.E.; Bryan, G.H.; Geeting, J.G.H.; Butner, R.S.

    1998-01-13T23:59:59.000Z

    The invention is a method and apparatus using high cerium concentration in the anolyte of an electrochemical cell to oxidize organic materials. The method and apparatus further use an ultrasonic mixer to enhance the oxidation rate of the organic material in the electrochemical cell. 6 figs.

  13. Exciton/Charge-transfer Electronic Couplings in Organic Semiconductors

    E-Print Network [OSTI]

    Difley, Seth

    Charge transfer (CT) states and excitons are important in energy conversion processes that occur in organic light emitting devices (OLEDS) and organic solar cells. An ab initio density functional theory (DFT) method for ...

  14. Evaluation of Radiation Resistance for Organic Materials

    E-Print Network [OSTI]

    McDonald, Kirk

    for organic materials used in atomic energy- related facilities J-PARC ITER Si-polymer Forming : fiber : "Radiation Resistivity of Polymeric Materials with Data Tables" (in Japanese) JAERI-Data/Code 2003 of Polymeric Materials with Data Tables" (in Japanese) JAERI-Data/Code 2003-015 C C H H H H n Polyethylene (PE

  15. High-Performance Solution-Processed Amorphous-Oxide-Semiconductor TFTs with Organic Polymeric Gate Dielectrics

    E-Print Network [OSTI]

    Pecunia, Vincenzo; Banger, Kulbinder; Sirringhaus, Henning

    2015-01-13T23:59:59.000Z

    energy offsets (? 1 eV) between the conduction/valence bands of the semiconductor and the gate dielectric are needed to confine the charge carriers at the active interface and minimize undesirable charge injection from the semiconductor into the gate... in solution, all the other polymers came in the form of pellets or powder and were dissolved in suitable anhydrous organic solvents: P?MS was dissolved in xylene at a concentration of 60 mg mL-1; SAN in butyronitrile at 40 mg mL-1; PC in 1,2-dichlorobenzene...

  16. Two-photon Photoemission of Organic Semiconductor Molecules on Ag(111)

    E-Print Network [OSTI]

    Yang, Aram

    2008-01-01T23:59:59.000Z

    Supramolecular organization in ultra-thin ?lms of alpha-sexithiophene on sili- con dioxide. Nature Materials,

  17. Quantum interference measurement of spin interactions in a bio-organic/semiconductor device structure

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

    Deo, Vincent [Ecole Polytechnique, Palaiseau (France); Virginia Tech, Blacksburg, VA (United States); Zhang, Yao [Virginia Tech, Blacksburg, VA (United States); Soghomonian, Victoria [Virginia Tech, Blacksburg, VA (United States); Heremans, Jean J. [Virginia Tech, Blacksburg, VA (United States)

    2015-03-30T23:59:59.000Z

    Quantum interference is used to measure the spin interactions between an InAs surface electron system and the iron center in the biomolecule hemin in nanometer proximity in a bio-organic/semiconductor device structure. The interference quantifies the influence of hemin on the spin decoherence properties of the surface electrons. The decoherence times of the electrons serve to characterize the biomolecule, in an electronic complement to the use of spin decoherence times in magnetic resonance. Hemin, prototypical for the heme group in hemoglobin, is used to demonstrate the method, as a representative biomolecule where the spin state of a metal ion affects biological functions. The electronic determination of spin decoherence properties relies on the quantum correction of antilocalization, a result of quantum interference in the electron system. Spin-flip scattering is found to increase with temperature due to hemin, signifying a spin exchange between the iron center and the electrons, thus implying interactions between a biomolecule and a solid-state system in the hemin/InAs hybrid structure. The results also indicate the feasibility of artificial bioinspired materials using tunable carrier systems to mediate interactions between biological entities.

  18. Quantum interference measurement of spin interactions in a bio-organic/semiconductor device structure

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

    Deo, Vincent; Zhang, Yao; Soghomonian, Victoria; Heremans, Jean J.

    2015-03-30T23:59:59.000Z

    Quantum interference is used to measure the spin interactions between an InAs surface electron system and the iron center in the biomolecule hemin in nanometer proximity in a bio-organic/semiconductor device structure. The interference quantifies the influence of hemin on the spin decoherence properties of the surface electrons. The decoherence times of the electrons serve to characterize the biomolecule, in an electronic complement to the use of spin decoherence times in magnetic resonance. Hemin, prototypical for the heme group in hemoglobin, is used to demonstrate the method, as a representative biomolecule where the spin state of a metal ion affects biologicalmore »functions. The electronic determination of spin decoherence properties relies on the quantum correction of antilocalization, a result of quantum interference in the electron system. Spin-flip scattering is found to increase with temperature due to hemin, signifying a spin exchange between the iron center and the electrons, thus implying interactions between a biomolecule and a solid-state system in the hemin/InAs hybrid structure. The results also indicate the feasibility of artificial bioinspired materials using tunable carrier systems to mediate interactions between biological entities.« less

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

    E-Print Network [OSTI]

    Yuan, Long; Yang, Jinlong

    2012-01-01T23:59:59.000Z

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

  20. Superatoms and Metal-Semiconductor Motifs for Cluster Materials

    SciTech Connect (OSTI)

    Castleman, A. W.

    2013-10-11T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Bishop, Sarah R.

    2010-01-01T23:59:59.000Z

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

  2. System for characterizing semiconductor materials and photovoltaic device

    DOE Patents [OSTI]

    Sopori, B.L.

    1996-12-03T23:59:59.000Z

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

  3. Exfoliation of self-assembled 2D organic-inorganic perovskite semiconductors

    E-Print Network [OSTI]

    Steiner, Ullrich

    Exfoliation of self-assembled 2D organic-inorganic perovskite semiconductors Wendy Niu,1,a) Anna-inorganic perovskite (C6H9C2H4NH3)2PbI4 are produced using micromechanical exfoliation. Mono- and few-layer areas microme- chanical exfoliation of 2D PbI perovskites and explore the few-layer behaviour of such systems

  4. Dry Lithography of Large-Area, Thin-Film Organic Semiconductors Using Frozen CO[subscript 2] Resists

    E-Print Network [OSTI]

    Mendoza, Hiroshi A.

    To address the incompatibility of organic semiconductors with traditional photolithography, an inert, frozen CO[subscript 2] resist is demonstrated that forms an in situ shadow mask. Contact with a room-temperature ...

  5. Organic materials for fusion-reactor applications

    SciTech Connect (OSTI)

    Hurley, G.F.; Coltman, R.R. Jr.

    1983-09-01T23:59:59.000Z

    Organic materials requirements for fusion-reactor magnets are described with reference to the temperature, radiation, and electrical and mechanical stress environment expected in these magnets. A review is presented of the response to gamma-ray and neutron irradiation at low temperatures of candidate organic materials; i.e. laminates, thin films, and potting compounds. Lifetime-limiting features of this response as well as needed testing under magnet operating conditions not yet adequately investigated are identified and recomendations for future work are made.

  6. Hydrogen in semiconductors and insulators

    E-Print Network [OSTI]

    Van de Walle, Chris G.

    2007-01-01T23:59:59.000Z

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

  7. Dynamics of excitons and charges in organic materials and semiconductor

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisitingContract ManagementDiscovering HowAnaDynamic Switching of the

  8. Effects of PMMA-transfer residues on the growth of organic semiconductor molecules on CVD graphene

    E-Print Network [OSTI]

    Kratzer, Markus; Bayer, Bernhard C.; Kidambi, Piran R.; Matkovi?, Aleksandar; Gaji?, Radoš; Cabrero-Vilatela, Andrea; Weatherup, Robert S.; Hofmann, Stephan; Teichert, Christian

    2015-03-09T23:59:59.000Z

    Scalably grown and transferred graphene is a highly promising material for organic electronic applications, but controlled interfacing of graphene thereby remains a key challenge. Here, we study the growth characteristics of the important organic...

  9. Sandia National Laboratories: metal-organic framework materials

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

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

  10. Shock-induced chemistry in organic materials

    SciTech Connect (OSTI)

    Dattelbaum, Dana M [Los Alamos National Laboratory; Sheffield, Steve [Los Alamos National Laboratory; Engelke, Ray [Los Alamos National Laboratory; Manner, Virginia [Los Alamos National Laboratory; Chellappa, Raja [Los Alamos National Laboratory; Yoo, Choong - Shik [WASHINGTON STATE UNIV

    2011-01-20T23:59:59.000Z

    The combined 'extreme' environments of high pressure, temperature, and strain rates, encountered under shock loading, offer enormous potential for the discovery of new paradigms in chemical reactivity not possible under more benign conditions. All organic materials are expected to react under these conditions, yet we currently understand very little about the first bond-breaking steps behind the shock front, such as in the shock initiation of explosives, or shock-induced reactivity of other relevant materials. Here, I will present recent experimental results of shock-induced chemistry in a variety of organic materials under sustained shock conditions. A comparison between the reactivity of different structures is given, and a perspective on the kinetics of reaction completion under shock drives.

  11. Organic materials with nonlinear optical properties

    DOE Patents [OSTI]

    Stupp, S.I.; Son, S.; Lin, H.C.

    1995-05-02T23:59:59.000Z

    The present invention is directed to organic materials that have the ability to double or triple the frequency of light that is directed through the materials. Particularly, the present invention is directed to the compound 4-[4-(2R)-2-cyano-7-(4{prime}-pentyloxy-4-biphenylcarbonyloxy)phenylheptylidenephenylcarbonyloxy]benzaldehyde, which can double the frequency of light that is directed through the compound. The invention is also directed to the compound (12-hydroxy-5,7-dodecadiynyl)-4{prime}-[(4{prime}-pentyloxy-4-biphenyl)carbonyloxy]-4-biphenylcarboxylate, and its polymeric form. The polymeric form can triple the frequency of light directed through it. 4 figs.

  12. Organic photosensitive cells grown on rough electrode with nano-scale morphology control

    DOE Patents [OSTI]

    Yang, Fan (Piscataway, NJ); Forrest, Stephen R. (Ann Arbor, MI)

    2011-06-07T23:59:59.000Z

    An optoelectronic device and a method for fabricating the optoelectronic device includes a first electrode disposed on a substrate, an exposed surface of the first electrode having a root mean square roughness of at least 30 nm and a height variation of at least 200 nm, the first electrode being transparent. A conformal layer of a first organic semiconductor material is deposited onto the first electrode by organic vapor phase deposition, the first organic semiconductor material being a small molecule material. A layer of a second organic semiconductor material is deposited over the conformal layer. At least some of the layer of the second organic semiconductor material directly contacts the conformal layer. A second electrode is deposited over the layer of the second organic semiconductor material. The first organic semiconductor material is of a donor-type or an acceptor-type relative to the second organic semiconductor material, which is of the other material type.

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

    SciTech Connect (OSTI)

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

    1997-07-01T23:59:59.000Z

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

  14. PHYSICAL REVIEW B 85, 075204 (2012) Semiclassical theory of magnetoresistance in positionally disordered organic semiconductors

    E-Print Network [OSTI]

    Flatte, Michael E.

    2012-01-01T23:59:59.000Z

    December 2011; published 7 February 2012) A recently introduced percolative theory of unipolar organic transport in organic materials is percolation theory.22,23 Recently a model24 has been developed of OMARPHYSICAL REVIEW B 85, 075204 (2012) Semiclassical theory of magnetoresistance in positionally

  15. Photoluminescence polarization anisotropy for studying long-range structural ordering within semiconductor multi-atomic alloys and organic crystals

    SciTech Connect (OSTI)

    Prutskij, T.; Percino, J. [Instituto de Ciencias, BUAP, Privada 17 Norte, No 3417, col. San Miguel Huyeotlipan, 72050, Puebla, Pue. (Mexico); Orlova, T. [Department of Chemical and Biochemical Engineering, University of Notre Dame, Notre Dame, IN (United States); Vavilova, L. [Ioffe Physical-Technical Institute, 26 Polytekhnicheskaya, St Petersburg 194021, Russian Federation (Russian Federation)

    2013-12-04T23:59:59.000Z

    Long-range structural ordering within multi-component semiconductor alloys and organic crystals leads to significant optical anisotropy and, in particular, to anisotropy of the photoluminescence (PL) emission. The PL emission of ternary and quaternary semiconductor alloys is polarized if there is some amount of the atomic ordering within the crystal structure. We analyze the polarization of the PL emission from the quaternary GaInAsP semiconductor alloy grown by Liquid Phase Epitaxy (LPE) and conclude that it could be caused by low degree atomic ordering within the crystal structure together with the thermal biaxial strain due to difference between the thermal expansion coefficients of the layer and the substrate. We also study the state of polarization of the PL from organic crystals in order to identify different features of the crystal PL spectrum.

  16. Modeling of the Thermoelectric Properties of Quasi-One-Dimensional Organic Semiconductors , A.A. Balandin2

    E-Print Network [OSTI]

    Modeling of the Thermoelectric Properties of Quasi-One-Dimensional Organic Semiconductors A. Casian Electrical conductivity , Seebeck coefficient S, electronic thermal conductivity e and the thermoelectric the general principles of solid state physics there is no upper limit for the thermoelectric figure of merit

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

    DOE Patents [OSTI]

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

    2001-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Kaindl, Robert A

    2011-01-01T23:59:59.000Z

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

  19. Organic Light-Emitting Diodes (OLEDs) and Optically-Detected Magnetic Resonance (ODMR) studies on organic materials

    SciTech Connect (OSTI)

    Cai, Min

    2011-11-30T23:59:59.000Z

    Organic semiconductors have evolved rapidly over the last decades and currently are considered as the next-generation technology for many applications, such as organic light-emitting diodes (OLEDs) in flat-panel displays (FPDs) and solid state lighting (SSL), and organic solar cells (OSCs) in clean renewable energy. This dissertation focuses mainly on OLEDs. Although the commercialization of the OLED technology in FPDs is growing and appears to be just around the corner for SSL, there are still several key issues that need to be addressed: (1) the cost of OLEDs is very high, largely due to the costly current manufacturing process; (2) the efficiency of OLEDs needs to be improved. This is vital to the success of OLEDs in the FPD and SSL industries; (3) the lifetime of OLEDs, especially blue OLEDs, is the biggest technical challenge. All these issues raise the demand for new organic materials, new device structures, and continued lower-cost fabrication methods. In an attempt to address these issues, we used solution-processing methods to fabricate highly efficient small molecule OLEDs (SMOLEDs); this approach is costeffective in comparison to the more common thermal vacuum evaporation. We also successfully made efficient indium tin oxide (ITO)-free SMOLEDs to further improve the efficiency of the OLEDs. We employed the spin-dependent optically-detected magnetic resonance (ODMR) technique to study the luminescence quenching processes in OLEDs and organic materials in order to understand the intrinsic degradation mechanisms. We also fabricated polymer LEDs (PLEDs) based on a new electron-accepting blue-emitting polymer and studied the effect of molecular weight on the efficiency of PLEDs. All these studies helped us to better understand the underlying relationship between the organic semiconductor materials and the OLEDs’ performance, and will subsequently assist in further enhancing the efficiency of OLEDs. With strongly improved device performance (in addition to other OLEDs' attributes such as mechanical flexibility and potential low cost), the OLED technology is promising to successfully compete with current technologies, such as LCDs and inorganic LEDs.

  20. Features of the spectral dependences of transmittance of organic semiconductors based on tert-butyl substituted lutetium phthalocyanine molecules

    SciTech Connect (OSTI)

    Belogorokhov, I. A., E-mail: jugqwerty@mail.ru [State Research and Project Institute of Rare-Metal Industry GIREDMET (Russian Federation); Tikhonov, E. V. [Moscow State University (Russian Federation); Dronov, M. A. [Russian Academy of Sciences, Prokhorov General Physics Institute (Russian Federation); Belogorokhova, L. I. [Moscow State University (Russian Federation); Ryabchikov, Yu. V. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Tomilova, L. G.; Khokhlov, D. R. [Moscow State University (Russian Federation)

    2011-11-15T23:59:59.000Z

    Vibronic properties of organic semiconductors based on tert-butyl substituted phthalocyanine lutetium diphthalocyanine molecules are studied by IR and Raman spectroscopy. It is shown that substitution of several carbon atoms in initial phthalocyanine (Pc) ligands with {sup 13}C isotope atoms causes a spectral shift in the main absorption lines attributed to benzene, isoindol, and peripheral C-H groups. A comparison of spectral characteristics showed that the shift can vary from 3 to 1 cm{sup -1}.

  1. X-ray characterization of solid small molecule organic materials

    SciTech Connect (OSTI)

    Billinge, Simon; Shankland, Kenneth; Shankland, Norman; Florence, Alastair

    2014-06-10T23:59:59.000Z

    The present invention provides, inter alia, methods of characterizing a small molecule organic material, e.g., a drug or a drug product. This method includes subjecting the solid small molecule organic material to x-ray total scattering analysis at a short wavelength, collecting data generated thereby, and mathematically transforming the data to provide a refined set of data.

  2. Exploring and enhancing conductivity in semiconductor nanoparticle films

    E-Print Network [OSTI]

    Porter, Venda Jane

    2007-01-01T23:59:59.000Z

    Semiconductor nanocrystals (NCs) are a promising material for use in opto-electronic devices as their optical properties tune with particle size. NCs formed via colloidal synthesis are suspended in solution by the organic ...

  3. Photoconversion of gasified organic materials into biologically-degradable plastics

    DOE Patents [OSTI]

    Weaver, Paul F. (Golden, CO); Maness, Pin-Ching (Golden, CO)

    1993-01-01T23:59:59.000Z

    A process is described for converting organic materials (such as biomass wastes) into a bioplastic suitable for use as a biodegradable plastic. In a preferred embodiment the process involves thermally gasifying the organic material into primarily carbon monoxide and hydrogen, followed by photosynthetic bacterial assimilation of the gases into cell material. The process is ideally suited for waste recycling and for production of useful biodegradable plastic polymer.

  4. Photoconversion of gasified organic materials into biologically-degradable plastics

    DOE Patents [OSTI]

    Weaver, P.F.; Pinching Maness.

    1993-10-05T23:59:59.000Z

    A process is described for converting organic materials (such as biomass wastes) into a bioplastic suitable for use as a biodegradable plastic. In a preferred embodiment the process involves thermally gasifying the organic material into primarily carbon monoxide and hydrogen, followed by photosynthetic bacterial assimilation of the gases into cell material. The process is ideally suited for waste recycling and for production of useful biodegradable plastic polymer. 3 figures.

  5. Graphene Produces More Efficient Charge Transport Inside an Organic

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

    Graphene Produces More Efficient Charge Transport Inside an Organic Semiconductor Graphene, a two dimensional semi-metal made of sp 2 hybridized carbon, is an outstanding material...

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

    E-Print Network [OSTI]

    Branham, Matthew S

    2008-01-01T23:59:59.000Z

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

  7. White organic light-emitting diodes: Status and perspective

    E-Print Network [OSTI]

    Reineke, Sebastian

    White organic light-emitting diodes (OLEDs) are ultrathin, large-area light sources made from organic semiconductor materials. Over the past decades, much research has been spent on finding suitable materials to realize ...

  8. Lithium-based inorganic-organic framework materials

    E-Print Network [OSTI]

    Yeung, Hamish Hei-Man

    2013-01-01T23:59:59.000Z

    This dissertation describes research into lithium-based inorganic-organic frameworks, which has led to an increased understanding of the structural diversity and properties of these materials. The crystal structures of 11 new forms of lithium...

  9. High mobility high efficiency organic films based on pure organic materials

    DOE Patents [OSTI]

    Salzman, Rhonda F. (Ann Arbor, MI); Forrest, Stephen R. (Ann Arbor, MI)

    2009-01-27T23:59:59.000Z

    A method of purifying small molecule organic material, performed as a series of operations beginning with a first sample of the organic small molecule material. The first step is to purify the organic small molecule material by thermal gradient sublimation. The second step is to test the purity of at least one sample from the purified organic small molecule material by spectroscopy. The third step is to repeat the first through third steps on the purified small molecule material if the spectroscopic testing reveals any peaks exceeding a threshold percentage of a magnitude of a characteristic peak of a target organic small molecule. The steps are performed at least twice. The threshold percentage is at most 10%. Preferably the threshold percentage is 5% and more preferably 2%. The threshold percentage may be selected based on the spectra of past samples that achieved target performance characteristics in finished devices.

  10. Center Organization | Center for Energy Efficient Materials

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWPSuccess StoriesFebruaryMetal nanoparticlesCenter Organization People

  11. Organic Photovoltaics | Center for Energy Efficient Materials

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItemResearch > TheNuclear Astrophysics One ofSpeedingthis siteOrg ChartOrganic

  12. Organic light emitting device architecture for reducing the number of organic materials

    DOE Patents [OSTI]

    D'Andrade, Brian (Westampton, NJ); Esler, James (Levittown, PA)

    2011-10-18T23:59:59.000Z

    An organic light emitting device is provided. The device includes an anode and a cathode. A first emissive layer is disposed between the anode and the cathode. The first emissive layer includes a first non-emitting organic material, which is an organometallic material present in the first emissive layer in a concentration of at least 50 wt %. The first emissive layer also includes a first emitting organic material. A second emissive layer is disposed between the first emissive layer and the cathode, preferably, in direct contact with the first emissive layer. The second emissive material includes a second non-emitting organic material and a second emitting organic material. The first and second non-emitting materials, and the first and second emitting materials, are all different materials. A first non-emissive layer is disposed between the first emissive layer and the anode, and in direct contact with the first emissive layer. The first non- emissive layer comprises the first non-emissive organic material.

  13. artificial organ materials: Topics by E-print Network

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

    artificial organ materials First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Deformable Organisms: An...

  14. Nitride semiconductor Surface and interface characterization and device design

    E-Print Network [OSTI]

    Zhang, Hongtao

    2006-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

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

  16. Photoconversion of organic materials into single-cell protein

    DOE Patents [OSTI]

    Weaver, Paul F. (13130 W. 66th Pl., Golden, CO 80401)

    2001-01-01T23:59:59.000Z

    A process is described for converting organic materials (such as biomass wastes) into sterile, high-grade bacterial protein suitable for use an animal feed or human food supplements. In a preferred embodiment the process involves thermally gasifying the organic material into primarily carbon monoxide, hydrogen and nitrogen products, followed by photosynthetic bacterial assimilation of the gases into cell material, which can be as high as 65% protein. The process is ideally suited for waste recycling and for food production under zero-gravity or extra-terrestrial conditions.

  17. Organic materials and devices for detecting ionizing radiation

    DOE Patents [OSTI]

    Doty, F. Patrick (Livermore, CA); Chinn, Douglas A. (Livermore, CA)

    2007-03-06T23:59:59.000Z

    A .pi.-conjugated organic material for detecting ionizing radiation, and particularly for detecting low energy fission neutrons. The .pi.-conjugated materials comprise a class of organic materials whose members are intrinsic semiconducting materials. Included in this class are .pi.-conjugated polymers, polyaromatic hydrocarbon molecules, and quinolates. Because of their high resistivities (.gtoreq.10.sup.9 ohmcm), these .pi.-conjugated organic materials exhibit very low leakage currents. A device for detecting and measuring ionizing radiation can be made by applying an electric field to a layer of the .pi.-conjugated polymer material to measure electron/hole pair formation. A layer of the .pi.-conjugated polymer material can be made by conventional polymer fabrication methods and can be cast into sheets capable of covering large areas. These sheets of polymer radiation detector material can be deposited between flexible electrodes and rolled up to form a radiation detector occupying a small volume but having a large surface area. The semiconducting polymer material can be easily fabricated in layers about 10 .mu.m to 100 .mu.m thick. These thin polymer layers and their associated electrodes can be stacked to form unique multi-layer detector arrangements that occupy small volume.

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

    SciTech Connect (OSTI)

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

    2012-11-06T23:59:59.000Z

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

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

    DOE Patents [OSTI]

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

    2013-09-17T23:59:59.000Z

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

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

    DOE Patents [OSTI]

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

    2011-02-15T23:59:59.000Z

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

  1. Organic materials for second harmonic generation. Final report

    SciTech Connect (OSTI)

    Twieg, R.J. (comp.)

    1985-03-31T23:59:59.000Z

    Materials were chosen by screening the Cambridge Crystallographic Index for new noncentrosymmetric crystalline compounds, by screening commercially available materials or by synthesis of unique new substances. Measurements were then made on the powder form of these materials. Langmuir-Blodgett films were deposited and studied. In addition to the above studies, a computer program was developed to calculate (hyper) polarizabilities of organic molecules and thus aid in the selection of materials for testing. The nonlinear molecules have been divided into three classes according to absorption cutoff: 400 to 500 nm, 300 to 400 nm, and 200 to 300 nm. 108 refs., 7 tabs. (WRF)

  2. Rational Design and Preparation of Organic Semiconductors for use in Field Effect Transistors and Photovoltaic Cells

    E-Print Network [OSTI]

    Mauldin, Clayton Edward

    2010-01-01T23:59:59.000Z

    in thin film organic photovoltaic cells (OPVs) is presented.efficient organic photovoltaic cells with power conversionEffect Transistors and Photovoltaic Cells By Clayton Edward

  3. Design, Synthesis, and Evaluation of Next Generation Technologies in Stimulus-Responsive Materials and Organic Electronics

    E-Print Network [OSTI]

    Unruh, Jr, David Allen

    2011-01-01T23:59:59.000Z

    Building Blocks in Organic Electronics Abstract The donor-performing organic electronics. Inspired by the desirableMaterials and Organic Electronics by David Allen Unruh, Jr.

  4. Method of photocatalytic conversion of C-H organics

    DOE Patents [OSTI]

    Camaioni, Donald M. (Richland, WA); Lilga, Michael A. (Richland, WA)

    1998-01-01T23:59:59.000Z

    The present invention is the addition of a semiconductor material and energy to the reaction mixture of organic, acid (for example, trifluoroacetate), and oxygen. A transition metal ion may be added to the reaction mixture. The semiconductor material converts energy to oxidants thereby promoting oxidation of the organic. Alternatively, using metal in combination with exposure to light may be used.

  5. Method of photocatalytic conversion of C-H organics

    DOE Patents [OSTI]

    Camaioni, D.M.; Lilga, M.A.

    1998-01-13T23:59:59.000Z

    The present invention is the addition of a semiconductor material and energy to the reaction mixture of organic, acid (for example, trifluoroacetate), and oxygen. A transition metal ion may be added to the reaction mixture. The semiconductor material converts energy to oxidants thereby promoting oxidation of the organic. Alternatively, using metal in combination with exposure to light may be used.

  6. High performance organic field-effect transistors with ultra-thin HfO{sub 2} gate insulator deposited directly onto the organic semiconductor

    SciTech Connect (OSTI)

    Ono, S., E-mail: shimpei@criepi.denken.or.jp [Central Research Institute of Electric Power Industry, Komae, Tokyo 201-8511 (Japan); Häusermann, R. [Central Research Institute of Electric Power Industry, Komae, Tokyo 201-8511 (Japan) [Central Research Institute of Electric Power Industry, Komae, Tokyo 201-8511 (Japan); Laboratory for Solid State Physics, ETH Zurich, Zurich 8093 (Switzerland); Chiba, D. [Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan) [Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho Kawaguchi, Saitama 322-0012 (Japan); Department of Applied Physics, University of Tokyo, Tokyo 113-8656 (Japan); Shimamura, K.; Ono, T. [Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)] [Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Batlogg, B. [Laboratory for Solid State Physics, ETH Zurich, Zurich 8093 (Switzerland)] [Laboratory for Solid State Physics, ETH Zurich, Zurich 8093 (Switzerland)

    2014-01-06T23:59:59.000Z

    We have produced stable organic field-effect transistors (OFETs) with an ultra-thin HfO{sub 2} gate insulator deposited directly on top of rubrene single crystals by atomic layer deposition (ALD). We find that ALD is a gentle deposition process to grow thin films without damaging rubrene single crystals, as results these devices have a negligibly small threshold voltage and are very stable against gate-bias-stress, and the mobility exceeds 1 cm{sup 2}/V s. Moreover, the devices show very little degradation even when kept in air for more than 2 months. These results demonstrate thin HfO{sub 2} layers deposited by ALD to be well suited as high capacitance gate dielectrics in OFETs operating at small gate voltage. In addition, the dielectric layer acts as an effective passivation layer to protect the organic semiconductor.

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

    DOE Patents [OSTI]

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

    2000-01-01T23:59:59.000Z

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

  8. Inorganic Chemistry Solutions to Semiconductor Nanocrystal Problems

    SciTech Connect (OSTI)

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

    2014-03-15T23:59:59.000Z

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

  9. Semiconductor bridge (SCB) detonator

    DOE Patents [OSTI]

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

    1999-01-19T23:59:59.000Z

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

  10. Semiconductor bridge (SCB) detonator

    DOE Patents [OSTI]

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

    1999-01-01T23:59:59.000Z

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

  11. On the inapplicability of electron-hopping models for the organic semiconductor Phenyl-C61-butyric Acid Methyl Ester (PCBM)

    SciTech Connect (OSTI)

    Gajdos, Fruzsina; Oberhofer, Harald; Dupuis, Michel; Blumberger, Jochen

    2013-03-21T23:59:59.000Z

    Phenyl-C61-butyric Acid Methyl Ester (PCBM) is one of the most popular semiconductors in organic photovoltaic cells, but the electron transport mechanism in the microcrystalline domains of this material as well as its preferred packing structure remains unclear. Here we use density functional theory to calculate electronic coupling matrix elements, reorganization energies and activation energies for available experimental and model crystal structures. We find that the picture of an excess electron hopping from one fullerene to another does not apply for any of the crystalline phases, rendering traditional rate equations inappropriate. We also find that the cohesive energy increases in the order body-centred-cubic < hexagonal < simple cubic < monoclinic < triclinic, independently on the type of dispersion correction used. Our results indicate that the electron-ion dynamics needs to be solved explicitly in order to obtain a realistic description of charge transfer in this material. M.D. was supported by the U.S. Department of Energy (DOE), Office of Basic Energy Sciences (BES), Division of Chemical Sciences, Geosciences and Biosciences. PNNL is a multiprogram national laboratory operated for DOE by Battelle.

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

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

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

  13. Rational Design and Preparation of Organic Semiconductors for use in Field Effect Transistors and Photovoltaic Cells

    E-Print Network [OSTI]

    Mauldin, Clayton Edward

    2010-01-01T23:59:59.000Z

    in thin film organic photovoltaic cells (OPVs) is presented.Effect Transistors and Photovoltaic Cells By Clayton EdwardEffect Transistors and Photovoltaic Cells By Clayton Edward

  14. 2012 DEFECTS IN SEMICONDUCTORS GORDON RESEARCH CONFERENCE, AUGUST 12-17, 2012

    SciTech Connect (OSTI)

    GLASER, EVAN

    2012-08-17T23:59:59.000Z

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

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

    DOE Patents [OSTI]

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

    2002-01-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

    Geisz, J.

    2010-07-01T23:59:59.000Z

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

  17. DOI: 10.1002/adem.200800289 Dewetting of an Organic Semiconductor Thin Film Observed

    E-Print Network [OSTI]

    Peters, Achim

    with controlled lateral distances and size. It has recently been shown that dewetting and thermal stability such as thin film transistors,[6] organic photovoltaics and organic light emitting diodes. In this paper we study the planar aromatic molecule diindenoperylene (DIP) as a model system, which has been shown

  18. Pattern Replication in Organic-Inorganic Hybrid Materials

    E-Print Network [OSTI]

    Nedelcu, Mihaela

    2014-05-27T23:59:59.000Z

    of an impeding fuel shortage and the need for clean renewable sources of energy, considerable effort has been made to reduce the cost of solar cells by primarily addressing the material processing techniques. Photo-electrochemical solar cells are an emerging... metal and the mesoporous TiO2 and Nb2O5, which have applications in dye sen- sitized solar cells. The first part of the thesis presents an overview of pattern formation in organic and inorganic materials and the working principles of dye sensitized solar...

  19. Method of doping a semiconductor

    DOE Patents [OSTI]

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

    1983-01-01T23:59:59.000Z

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

  20. Rational Design and Preparation of Organic Semiconductors for use in Field Effect Transistors and Photovoltaic Cells

    E-Print Network [OSTI]

    Mauldin, Clayton Edward

    2010-01-01T23:59:59.000Z

    supramolecular chemistry are central to the design and development of these materialssupramolecular comb polymer structures. 5. Methods 5.1 Materials.

  1. Novel patterning techniques for manufacturing organic and nanostructured electronics

    E-Print Network [OSTI]

    Chen, Jianglong, 1976-

    2007-01-01T23:59:59.000Z

    Molecular organic semiconductors and nanometer size particles are two new classes of functional materials allowing fabrication of electronic devices on low-cost and large area substrates. Patterning these electronic materials ...

  2. Alternative methods and materials for patterning organic thin film electronics

    E-Print Network [OSTI]

    Bahlke, Matthias Erhard

    2014-01-01T23:59:59.000Z

    Photolithography's accuracy and scalability have made it the method for sub-micronscale definition of single-crystal semiconductor devices for over half a century. The ultimate goal for OLED manufacturing, however, is to ...

  3. The Development of Semiconducting Materials for Organic Photovoltaics

    E-Print Network [OSTI]

    Douglas, Jessica D.

    2013-01-01T23:59:59.000Z

    of Organic Photovoltaic Device Efficiency……………………………..4of Organic Photovoltaic Device Efficiency The efficiency atpower conversion efficiency of organic photovoltaic devices.

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

    DOE Patents [OSTI]

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

    2014-12-30T23:59:59.000Z

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

  5. Predictions of Hole Mobilities in Oligoacene Organic Semiconductors from Quantum Mechanical Calculations

    E-Print Network [OSTI]

    Goddard III, William A.

    hole mobility. Electronic band structure calculations have previously been used to predict charge the reorganization energy and electron-transfer coupling matrix elements and molecular dynamics (MD) to do Calculations Wei-Qiao Deng and William A. Goddard III* Materials and Process Simulation Center, California

  6. Method of passivating semiconductor surfaces

    DOE Patents [OSTI]

    Wanlass, Mark W. (Golden, CO)

    1990-01-01T23:59:59.000Z

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

  7. Method of passivating semiconductor surfaces

    DOE Patents [OSTI]

    Wanlass, M.W.

    1990-06-19T23:59:59.000Z

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

  8. Testing of organic waste surrogate materials in support of the Hanford organic tank program. Final report

    SciTech Connect (OSTI)

    Turner, D.A. [Westinghouse Hanford Co., Richland, WA (United States); Miron, Y. [Bureau of Mines (United States)

    1994-01-01T23:59:59.000Z

    To address safety issues regarding effective waste management efforts of underground organic waste storage tanks at the Hanford Site, the Bureau of Mines conducted a series of tests, at the request of the Westinghouse Hanford company. In this battery of tests, the thermal and explosive characteristics of surrogate materials, chosen by Hanford, were determined. The surrogate materials were mixtures of inorganic and organic sodium salts, representing fuels and oxidants. The oxidants were sodium nitrate and sodium nitrite. The fuels were sodium salts of oxalate, citrate and ethylenediamine tetraacetic acid (EDTA). Polyethylene powder was also used as a fuel with the oxidant(s). Sodium aluminate was used as a diluent. In addition, a sample of FeCN, supplied by Hanford was also investigated.

  9. The Development of Semiconducting Materials for Organic Photovoltaics

    E-Print Network [OSTI]

    Douglas, Jessica D.

    2013-01-01T23:59:59.000Z

    F. C. ; Norrman, K. Prog. Photovoltaics 2007, 15, 697–712.Processed Organic Photovoltaics that Generate Chargepolymer-based organic photovoltaics (OPVs) have attracted

  10. Faculty and Instructional Staff in the UW-Madison Department of Materials Science & Engineering

    E-Print Network [OSTI]

    Wisconsin at Madison, University of

    , nuclear fuels, energy policy, sustainability of nuclear energy. Mark A Eriksson Professor, Physics: photovoltaic solar cells, organic light emitting diodes; materials for alternative energy and energy storage synthesis and characterization, electronic and semiconductor materials, solar energy and photovoltaics

  11. High liquid yield process for retorting various organic materials including oil shale

    DOE Patents [OSTI]

    Coburn, Thomas T. (Livermore, CA)

    1990-01-01T23:59:59.000Z

    This invention is a continuous retorting process for various high molecular weight organic materials, including oil shale, that yields an enhanced output of liquid product. The organic material, mineral matter, and an acidic catalyst, that appreciably adsorbs alkenes on surface sites at prescribed temperatures, are mixed and introduced into a pyrolyzer. A circulating stream of olefin enriched pyrolysis gas is continuously swept through the organic material and catalyst, whereupon, as the result of pyrolysis, the enhanced liquid product output is provided. Mixed spent organic material, mineral matter, and cool catalyst are continuously withdrawn from the pyrolyzer. Combustion of the spent organic material and mineral matter serves to reheat the catalyst. Olefin depleted pyrolysis gas, from the pyrolyzer, is enriched in olefins and recycled into the pyrolyzer. The reheated acidic catalyst is separated from the mineral matter and again mixed with fresh organic material, to maintain the continuously cyclic process.

  12. A high liquid yield process for retorting various organic materials including oil shale

    DOE Patents [OSTI]

    Coburn, T.T.

    1988-07-26T23:59:59.000Z

    This invention is a continuous retorting process for various high molecular weight organic materials, including oil shale, that yields an enhanced output of liquid product. The organic material, mineral matter, and an acidic catalyst, that appreciably adsorbs alkenes on surface sites at prescribed temperatures, are mixed and introduced into a pyrolyzer. A circulating stream of olefin enriched pyrolysis gas is continuously swept through the organic material and catalyst, whereupon, as the result of pyrolysis, the enhanced liquid product output is provided. Mixed spent organic material, mineral matter, and cool catalyst are continuously withdrawn from the pyrolyzer. Combustion of the spent organic material and mineral matter serves to reheat the catalyst. Olefin depleted pyrolysis gas, from the pyrolyzer, is enriched in olefins and recycled into the pyrolyzer. The reheated acidic catalyst is separated from the mineral matter and again mixed with fresh organic material, to maintain the continuously cyclic process. 2 figs.

  13. Variable temperature semiconductor film deposition

    DOE Patents [OSTI]

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

    1998-01-01T23:59:59.000Z

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

  14. Process for producing chalcogenide semiconductors

    DOE Patents [OSTI]

    Noufi, R.; Chen, Y.W.

    1985-04-30T23:59:59.000Z

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

  15. Variable temperature semiconductor film deposition

    DOE Patents [OSTI]

    Li, X.; Sheldon, P.

    1998-01-27T23:59:59.000Z

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

  16. Process for producing chalcogenide semiconductors

    DOE Patents [OSTI]

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

    1987-01-01T23:59:59.000Z

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

  17. The Development of Semiconducting Materials for Organic Photovoltaics

    E-Print Network [OSTI]

    Douglas, Jessica D.

    2013-01-01T23:59:59.000Z

    photovoltaics (OPVs) has led to a significant increase in their power conversion efficiencies (Photovoltaics…………………………..………1 Motivation and Current Technology………………………………………………………1 Organic Photovoltaic Device Operation and Structure……………………………………2 Characterization of Organic Photovoltaic Device Efficiency……………………………..

  18. Polymer and carbon nanotube materials for chemical sensors and organic electronics

    E-Print Network [OSTI]

    Wang, Fei, Ph. D. Massachusetts Institute of Technology

    2010-01-01T23:59:59.000Z

    This thesis details the development of new materials for high-performance chemical sensing as well as organic electronic applications. In Chapter 2, we develop a chemiresistive material based on single-walled carbon nanotubes ...

  19. Spectroscopy of semiconductor materials

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

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

  20. Isotopically controlled semiconductors

    E-Print Network [OSTI]

    Haller, Eugene E.

    2006-01-01T23:59:59.000Z

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

  1. Raman scattering in organic semiconductors based on erbium biphthalocyanine molecules and chlorine-containing europium-lutetium triphthalocyanine molecules

    SciTech Connect (OSTI)

    Belogorokhov, I. A., E-mail: jugqwerty@mail.ru [Federal State Research and Design Institute for Rare-Metal Industry (Russian Federation); Mamichev, D. A.; Dronov, M. A.; Pushkarev, V. E.; Tomilova, L. G.; Khokhlov, D. R. [Moscow State University (Russian Federation)

    2010-08-15T23:59:59.000Z

    The Raman spectra of semiconductor structures based on erbium biphthalocyanine molecules and chlorine-substituted europium-lutetium triphthalocyanine molecules are studied on excitation with Ar{sup +} laser radiation at the wavelength 514 nm. The data on the spectral position of Raman intensity peaks related to vibronic states of the basic molecular groups forming the semiconductor are obtained. Raman lines irrelevant to the known vibronic states of the basic phthalocyanine molecular groups are observed in the ranges 100-500 and 500-900 cm{sup -1}. It is shown that, in the spectra of triphthalocyanine, some lines are structurally complex and shifted with respect to the characteristic lines of molecular groups by several inverse centimeters.

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

    E-Print Network [OSTI]

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

  3. Micromachined printheads for the direct evaporative patterning of organic materials

    E-Print Network [OSTI]

    Leblanc, Valérie, Ph. D. Massachusetts Institute of Technology

    2007-01-01T23:59:59.000Z

    Organic optoelectronic devices are appealing for low-performance applications on very low cost and flexible substrates, due to their low-temperature processing. However, it still remains a challenge to develop suitable ...

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

    DOE Patents [OSTI]

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

    2014-08-05T23:59:59.000Z

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

  5. INVITED REVIEW Self-organized nanotube materials and their

    E-Print Network [OSTI]

    Cai, Long

    toward the multiscale self-assembly of materials from the molecular or nano- structure level upwards with this trend, research on supramolecular nanotube architectures2­8 with a well-defined hollow cylindrical to the function of these hollow cylinders themselves, such as their encapsulation ability.8,27 On the other hand

  6. Microporous Materials Strategies for Hydrogen Storage in MetalOrganic

    E-Print Network [OSTI]

    Yaghi, Omar M.

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

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

    E-Print Network [OSTI]

    Park, Jinhee

    2013-04-19T23:59:59.000Z

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

  8. Measurement and control of exciton spin in organic light emitting devices

    E-Print Network [OSTI]

    Segal, Michael, Ph. D. Massachusetts Institute of Technology

    2007-01-01T23:59:59.000Z

    Organic semiconductors are a promising new material set for electronic and optoelectronic devices. Their properties can be precisely controlled through chemistry, and they are well-suited for large-area, flexible, and ...

  9. Purchasing and Materials Management Organization, Sandia National Laboratories annual report, fiscal year 1993

    SciTech Connect (OSTI)

    Martin, D.R.

    1994-02-01T23:59:59.000Z

    This report summarizes the purchasing and transportation activities of the Purchasing and Materials Management Organization for Fiscal Year 1993. Activities for both the New Mexico and California locations are included.

  10. Chemistry and Applications of Metal-Organic Materials

    E-Print Network [OSTI]

    Zhao, Dan

    2012-02-14T23:59:59.000Z

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

  11. Controlled growth of larger heterojunction interface area for organic photosensitive devices

    DOE Patents [OSTI]

    Yang, Fan (Somerset, NJ); Forrest, Stephen R. (Ann Arbor, MI)

    2009-12-29T23:59:59.000Z

    An optoelectronic device and a method of fabricating a photosensitive optoelectronic device includes depositing a first organic semiconductor material on a first electrode to form a continuous first layer having protrusions, a side of the first layer opposite the first electrode having a surface area at least three times greater than an underlying lateral cross-sectional area; depositing a second organic semiconductor material directly on the first layer to form a discontinuous second layer, portions of the first layer remaining exposed; depositing a third organic semiconductor material directly on the second layer to form a discontinuous third layer, portions of at least the second layer remaining exposed; depositing a fourth organic semiconductor material on the third layer to form a continuous fourth layer, filling any exposed gaps and recesses in the first, second, and third layers; and depositing a second electrode on the fourth layer, wherein at least one of the first electrode and the second electrode is transparent, and the first and third organic semiconductor materials are both of a donor-type or an acceptor-type relative to second and fourth organic semiconductor materials, which are of the other material type.

  12. Hybrid metal organic scintillator materials system and particle detector

    DOE Patents [OSTI]

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

    2011-07-26T23:59:59.000Z

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

  13. Factors Affecting the Battery Performance of Anthraquinone-based Organic Cathode Materials

    SciTech Connect (OSTI)

    Xu, Wu; Read, Adam L.; Koech, Phillip K.; Hu, Dehong; Wang, Chong M.; Xiao, Jie; Padmaperuma, Asanga B.; Graff, Gordon L.; Liu, Jun; Zhang, Jiguang

    2012-02-01T23:59:59.000Z

    Two organic cathode materials based on poly(anthraquinonyl sulfide) structure with different substitution positions were synthesized and their electrochemical behavior and battery performances were investigated. The substitution positions on the anthraquinone structure, binders for electrode preparation and electrolyte formulations have been found to have significant effects on the battery performances of such organic cathode materials. The substitution position with less steric stress has higher capacity, longer cycle life and better high-rate capability. Polyvinylidene fluoride binder and ether-based electrolytes are favorable for the high capacity and long cycle life of the quinonyl organic cathodes.

  14. SEMICONDUCTOR DETECTORS - AN INTRODUCTION

    E-Print Network [OSTI]

    Goulding, F.S.

    2011-01-01T23:59:59.000Z

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

  15. Isotopically controlled semiconductors

    E-Print Network [OSTI]

    Haller, E.E.

    2004-01-01T23:59:59.000Z

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

  16. Semiconductor Nanowires: What's Next?

    E-Print Network [OSTI]

    Yang, Peidong

    2011-01-01T23:59:59.000Z

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

  17. Testing of organic waste surrogate materials in support of the Hanford organic tank program. Final supplementary report, Supplement 1

    SciTech Connect (OSTI)

    Turner, D.A. [Westinghouse Hanford Co., Richland, WA (United States); Miron, Y. [Bureau of Mines (United States)

    1994-01-01T23:59:59.000Z

    To address safety issues regarding effective waste management efforts of underground organic waste storage tanks at the Hanford Site, the Bureau of Mines conducted a series of supplemental tests, at the request of the Westinghouse Hanford Company. In this series of supplemental tests, the thermal characteristics of surrogate materials, chosen by Hanford, were determined. The surrogate materials were mixtures of organic and inorganic sodium salts, representing fuels and oxidants. The oxidants were sodium nitrate and sodium nitrite. The fuels were sodium salts of acetate, stearate, and oxalate. Sodium hydroxide was also an ingredient of the mixtures, used to maintain basic conditions. The fuels and all the mixtures of this report were tested by differential scanning calorimetry and by thermogravimetric analysis.

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

    E-Print Network [OSTI]

    Zhao, Yuxiao

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

  19. Charge migration in organic materials: Can propagating charges affect the key physical quantities controlling their motion?

    E-Print Network [OSTI]

    Gollub, C; Gutierrez, R; Berlin, Y; Cuniberti, G

    2012-01-01T23:59:59.000Z

    Charge migration is a ubiquitous phenomenon with profound implications throughout many areas of chemistry, physics, biology and materials science. The long-term vision of designing functional materials with tailored molecular scale properties has triggered an increasing quest to identify prototypical systems where truly molecular conduction pathways play a fundamental role. Such pathways can be formed due to the molecular organization of various organic materials and are widely used to discuss electronic properties at the nanometer scale. Here, we present a computational methodology to study charge propagation in organic molecular stacks at nano and sub-nanoscales and exploit this methodology to demonstrate that moving charge carriers strongly affect the values of the physical quantities controlling their motion. The approach is also expected to find broad application in the field of charge migration in soft matter systems.

  20. Method for the catalytic conversion of organic materials into a product gas

    DOE Patents [OSTI]

    Elliott, Douglas C. (Richland, WA); Sealock, Jr., L. John (Richland, WA); Baker, Eddie G. (Richland, WA)

    1997-01-01T23:59:59.000Z

    A method for converting organic material into a product gas includes: a) providing a liquid reactant mixture containing liquid water and liquid organic material within a pressure reactor; b) providing an effective amount of a reduced metal catalyst selected from the group consisting of ruthenium, rhodium, osmium and iridium or mixtures thereof within the pressure reactor; and c) maintaining the liquid reactant mixture and effective amount of reduced metal catalyst in the pressure reactor at temperature and pressure conditions of from about 300.degree. C. to about 450.degree. C.; and at least 130 atmospheres for a period of time, the temperature and pressure conditions being effective to maintain the reactant mixture substantially as liquid, the effective amount of reduced metal catalyst and the period of time being sufficient to catalyze a reaction of the liquid organic material to produce a product gas composed primarily of methane, carbon dioxide and hydrogen.

  1. Method for the catalytic conversion of organic materials into a product gas

    DOE Patents [OSTI]

    Elliott, D.C.; Sealock, L.J. Jr.; Baker, E.G.

    1997-04-01T23:59:59.000Z

    A method for converting organic material into a product gas includes: (a) providing a liquid reactant mixture containing liquid water and liquid organic material within a pressure reactor; (b) providing an effective amount of a reduced metal catalyst selected from the group consisting of ruthenium, rhodium, osmium and iridium or mixtures thereof within the pressure reactor; and (c) maintaining the liquid reactant mixture and effective amount of reduced metal catalyst in the pressure reactor at temperature and pressure conditions of from about 300 C to about 450 C; and at least 130 atmospheres for a period of time, the temperature and pressure conditions being effective to maintain the reactant mixture substantially as liquid, the effective amount of reduced metal catalyst and the period of time being sufficient to catalyze a reaction of the liquid organic material to produce a product gas composed primarily of methane, carbon dioxide and hydrogen. 5 figs.

  2. CONTRIBUTION OF SEMI-VOLATILE ORGANIC MATERIAL TO AMBIENT PM2.5

    SciTech Connect (OSTI)

    Delbert J. Eatough; William K. Modey; Rebecca Sizemore; Michael Simpson

    2004-04-01T23:59:59.000Z

    Both annual 24-h average and seasonal diurnal samples collected at NETL during the research program have been analyzed. The fine particulate components determined include PM{sub 2.5} mass, ammonium sulfate, ammonium nitrate, elemental and organic carbonaceous material and trace elements. The analysis of the nitrate and organic material includes both the identification of nonvolatile material retained by the particle collection filter and semi-volatile material lost from the particles during sample collection. The results obtained in these analyses indicate that both the semivolatile and nonvolatile organic material in the fine particles sampled at the NETL site originate from mobile emissions in the local area. However, the majority of the nonvolatile material is associated with primary emissions and the majority of the semi-volatile material is secondary, being formed from photochemical processes in the atmosphere. In contrast, the fine particulate sulfate does not originate from the local area but is transported into the study region, mostly from sources in the Ohio River Valley. These observations have been supported by both detailed meteorological and apportionment analysis of the data.

  3. 1.0. Semiconductor Diodes 1 of 27 1.2 Ideal Diode

    E-Print Network [OSTI]

    Allen, Gale

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

  4. Back-side readout semiconductor photomultiplier

    DOE Patents [OSTI]

    Choong, Woon-Seng; Holland, Stephen E

    2014-05-20T23:59:59.000Z

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

  5. ICA PreConference: What is an Organization? Materiality, Agency and Discourse, Montral, May 21-22, 2008

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    complexity theory are widely used in organization theory. However, research on complexity in organization can be no more than metaphorical (Stacey et al., 2000). Metaphors are commonly found in organization theory1 ICA PreConference: What is an Organization? Materiality, Agency and Discourse, Montréal, May 21

  6. Mn-Substituted Inorganic-Organic Hybrid Materials Based on ZnSe

    E-Print Network [OSTI]

    Li, Jing

    for optoelectronics and information storage technology. In this study, we demonstrate that the hybrid nanostructuresMn-Substituted Inorganic-Organic Hybrid Materials Based on ZnSe: Nanostructures That May Lead are highly desirable and extremely attractive in the development of new multifunctional devices

  7. Life in the Solar System Assume we need energy, liquid water, and organic materials.

    E-Print Network [OSTI]

    Shirley, Yancy

    high pressure, no sunlight, high temperature. Not much chance of life there. Gas Giants #12;The moonsLife in the Solar System Assume we need energy, liquid water, and organic materials. #12;Size N2 Titan Thick atmo Thick atmo Thin atmo #12;Small rocky bodies are unlikely to host life: too hot

  8. What is compost? Composting refers to biological decomposition and stabilization of organic materials by microorganisms under

    E-Print Network [OSTI]

    Mukhtar, Saqib

    What is compost? Composting refers to biological decomposition and stabilization of organic materials by microorganisms under aerobic conditions (in the presence of oxygen). During the composting is production of good-quality compost that is biologically stable, relatively uniform in appearance, free

  9. Iodine as a tracer of organic material: 129 I results from gas hydrate

    E-Print Network [OSTI]

    Fehn, Udo

    Iodine as a tracer of organic material: 129 I results from gas hydrate systems and fore arc fluids of this system, investigations of gas hydrates from the Peru Margin (ODP 201, Site 1230) and of fluids collected for these fluids. The results are in good agreement with earlier investigations of gas hydrate systems at Blake

  10. Stretchable semiconductor elements and stretchable electrical circuits

    DOE Patents [OSTI]

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

    2009-07-07T23:59:59.000Z

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

  11. Layered semiconductor neutron detectors

    DOE Patents [OSTI]

    Mao, Samuel S; Perry, Dale L

    2013-12-10T23:59:59.000Z

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

  12. Wafer-fused semiconductor radiation detector

    DOE Patents [OSTI]

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

    2002-01-01T23:59:59.000Z

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

  13. Patterning Organic Electronics Based on Nanoimprint Lithography

    E-Print Network [OSTI]

    Lo, Yi-Chen

    2014-04-25T23:59:59.000Z

    with organic semiconductors. This technique was then used to fabricate passive-matrix organic light-emitting diode (PMOLED) arrays for flat-panel display applications. Fabrication of a self-aligned bottom gate electrode for organic metal semiconductor field...

  14. Silicon surface passivation by an organic overlayer of 9,10-phenanthrenequinone

    E-Print Network [OSTI]

    ,10-phenanthrenequinone, PQ . PQ reacts with the dangling bonds, thus providing a bridge between organic semiconductors in integrating organic and silicon-based semiconductor devices.1­3 Organic- semiconductor/silicon interfaces can

  15. Megahertz organic/polymer diodes

    DOE Patents [OSTI]

    Katz, Howard Edan; Sun, Jia; Pal, Nath Bhola

    2012-12-11T23:59:59.000Z

    Featured is an organic/polymer diode having a first layer composed essentially of one of an organic semiconductor material or a polymeric semiconductor material and a second layer formed on the first layer and being electrically coupled to the first layer such that current flows through the layers in one direction when a voltage is applied in one direction. The second layer is essentially composed of a material whose characteristics and properties are such that when formed on the first layer, the diode is capable of high frequency rectifications on the order of megahertz rectifications such as for example rectifications at one of above 100KHz, 500KhZ, IMHz, or 10 MHz. In further embodiments, the layers are arranged so as to be exposed to atmosphere.

  16. The role of inertial and spatial confinement in laser interaction with organic materials Leonid V. Zhigilei,1)

    E-Print Network [OSTI]

    ], and manufacturing of electronic devices [4,5]. A complete understanding of the laser-induced processes is required#12;215 The role of inertial and spatial confinement in laser interaction with organic materials author, e-mail: lz2n@virginia.edu ABSTRACT Short-pulse laser irradiation of organic material performed

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

    E-Print Network [OSTI]

    Li, Jing

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

  18. Methods of chemical analysis for organic waste constituents in radioactive materials: A literature review

    SciTech Connect (OSTI)

    Clauss, S.A.; Bean, R.M.

    1993-02-01T23:59:59.000Z

    Most of the waste generated during the production of defense materials at Hanford is presently stored in 177 underground tanks. Because of the many waste treatment processes used at Hanford, the operations conducted to move and consolidate the waste, and the long-term storage conditions at elevated temperatures and radiolytic conditions, little is known about most of the organic constituents in the tanks. Organics are a factor in the production of hydrogen from storage tank 101-SY and represent an unresolved safety question in the case of tanks containing high organic carbon content. In preparation for activities that will lead to the characterization of organic components in Hanford waste storage tanks, a thorough search of the literature has been conducted to identify those procedures that have been found useful for identifying and quantifying organic components in radioactive matrices. The information is to be used in the planning of method development activities needed to characterize the organics in tank wastes and will prevent duplication of effort in the development of needed methods.

  19. Preparation of a semiconductor thin film

    DOE Patents [OSTI]

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

    1998-01-27T23:59:59.000Z

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

  20. Preparation of a semiconductor thin film

    DOE Patents [OSTI]

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

    1998-01-01T23:59:59.000Z

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

  1. Development and Utilization of Host Materials for White Phosphorescent Organic Light-Emitting Diodes

    SciTech Connect (OSTI)

    Tang, Ching; Chen, Shaw

    2013-05-31T23:59:59.000Z

    Our project was primarily focused on the MYPP 2015 goal for white phosphorescent organic devices (PhOLEDs or phosphorescent organic light-emitting diodes) for solid-state lighting with long lifetimes and high efficiencies. Our central activity was to synthesize and evaluate a new class of host materials for blue phosphors in the PhOLEDs, known to be a weak link in the device operating lifetime. The work was a collaborative effort between three groups, one primarily responsible for chemical design and characterization (Chen), one primarily responsible for device development (Tang) and one primarily responsible for mechanistic studies and degradation analysis (Rothberg). The host materials were designed with a novel architecture that chemically links groups with good ability to move electrons with those having good ability to move “holes” (positive charges), the main premise being that we could suppress the instability associated with physical separation and crystallization of the electron conducting and hole conducting materials that might cause the devices to fail. We found that these materials do prevent crystallization and that this will increase device lifetimes but that efficiencies were reduced substantially due to interactions between the materials creating new low energy “charge transfer” states that are non-luminescent. Therefore, while our proposed strategy could in principle improve device lifetimes, we were unable to find a materials combination where the efficiency was not substantially compromised. In the course of our project, we made several important contributions that are peripherally related to the main project goal. First, we were able to prepare the proposed new family of materials and develop synthetic routes to make them efficiently. These types of materials that can transport both electrons and holes may yet have important roles to play in organic device technology. Second we developed an important new method for controlling the deposition profile of material so that arbitrary concentration gradients can be implemented in layers with mixed composition. These concentration profiles are known to increase device efficiency and longevity and we confirmed that experimentally. Third, we investigated a new method for analyzing degradation in devices using mass spectrometry to look for degradation products. We showed that these methods are not simple to interpret unambiguously and need to be used with caution.

  2. Method for removing semiconductor layers from salt substrates

    DOE Patents [OSTI]

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

    1985-08-27T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Deng, Xunming

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

  4. Neural network system and methods for analysis of organic materials and structures using spectral data

    DOE Patents [OSTI]

    Meyer, Bernd J. (Athens, GA); Sellers, Jeffrey P. (Suwanee, GA); Thomsen, Jan U. (Fredricksberg, DK)

    1993-01-01T23:59:59.000Z

    Apparatus and processes for recognizing and identifying materials. Characteristic spectra are obtained for the materials via spectroscopy techniques including nuclear magnetic resonance spectroscopy, infrared absorption analysis, x-ray analysis, mass spectroscopy and gas chromatography. Desired portions of the spectra may be selected and then placed in proper form and format for presentation to a number of input layer neurons in an offline neural network. The network is first trained according to a predetermined training process; it may then be employed to identify particular materials. Such apparatus and processes are particularly useful for recognizing and identifying organic compounds such as complex carbohydrates, whose spectra conventionally require a high level of training and many hours of hard work to identify, and are frequently indistinguishable from one another by human interpretation.

  5. Neural network system and methods for analysis of organic materials and structures using spectral data

    DOE Patents [OSTI]

    Meyer, B.J.; Sellers, J.P.; Thomsen, J.U.

    1993-06-08T23:59:59.000Z

    Apparatus and processes are described for recognizing and identifying materials. Characteristic spectra are obtained for the materials via spectroscopy techniques including nuclear magnetic resonance spectroscopy, infrared absorption analysis, x-ray analysis, mass spectroscopy and gas chromatography. Desired portions of the spectra may be selected and then placed in proper form and format for presentation to a number of input layer neurons in an offline neural network. The network is first trained according to a predetermined training process; it may then be employed to identify particular materials. Such apparatus and processes are particularly useful for recognizing and identifying organic compounds such as complex carbohydrates, whose spectra conventionally require a high level of training and many hours of hard work to identify, and are frequently indistinguishable from one another by human interpretation.

  6. Life-cycle Assessment of Semiconductors

    E-Print Network [OSTI]

    Boyd, Sarah B.

    2009-01-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    2008-09-01T23:59:59.000Z

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

  8. Phase Transitions and Phase Miscibility of Mixed Particles of Ammonium Sulfate, Toluene-Derived Secondary Organic Material,

    E-Print Network [OSTI]

    related to air quality and climate. The phases of particles containing secondary organic materials (SOMs humidity (RH), and temperature.2-5 Phase transitions of crystalline inorganic materials commonly found-8 These materials change from a crystalline solid to a saturated aqueous solution at the deliquescence relative

  9. Direct comparative study on the energy level alignments in unoccupied/occupied states of organic semiconductor/electrode interface by constructing in-situ photoemission spectroscopy and Ar gas cluster ion beam sputtering integrated analysis system

    SciTech Connect (OSTI)

    Yun, Dong-Jin, E-mail: Dongjin.yun@samsung.com; Chung, JaeGwan; Kim, Yongsu; Park, Sung-Hoon; Kim, Seong-Heon; Heo, Sung [Analytical Science Laboratory of Samsung Advanced Institute of Technology, PO Box 14-1, Yongin 446-712 (Korea, Republic of)

    2014-10-21T23:59:59.000Z

    Through the installation of electron gun and photon detector, an in-situ photoemission and damage-free sputtering integrated analysis system is completely constructed. Therefore, this system enables to accurately characterize the energy level alignments including unoccupied/occupied molecular orbital (LUMO/HOMO) levels at interface region of organic semiconductor/electrode according to depth position. Based on Ultraviolet Photoemission Spectroscopy (UPS), Inverse Photoemission Spectroscopy (IPES), and reflective electron energy loss spectroscopy, the occupied/unoccupied state of in-situ deposited Tris[4-(carbazol-9-yl)phenyl]amine (TCTA) organic semiconductors on Au (E{sub LUMO}: 2.51?eV and E{sub HOMO}: 1.35?eV) and Ti (E{sub LUMO}: 2.19?eV and E{sub HOMO}: 1.69?eV) electrodes are investigated, and the variation of energy level alignments according to work function of electrode (Au: 4.81?eV and Ti: 4.19?eV) is clearly verified. Subsequently, under the same analysis condition, the unoccupied/occupied states at bulk region of TCTA/Au structures are characterized using different Ar gas cluster ion beam (Ar GCIB) and Ar ion sputtering processes, respectively. While the Ar ion sputtering process critically distorts both occupied and unoccupied states in UPS/IPES spectra, the Ar GCIB sputtering process does not give rise to damage on them. Therefore, we clearly confirm that the in-situ photoemission spectroscopy in combination with Ar GCIB sputtering allows of investigating accurate energy level alignments at bulk/interface region as well as surface region of organic semiconductor/electrode structure.

  10. Inorganic-organic hybrid materials and abrasion resistant coatings based on a sol-gel approach

    SciTech Connect (OSTI)

    Betrabet, C.S.

    1993-01-01T23:59:59.000Z

    Attempts to synthesize hybrid materials from polytetramethylene oxide (PTMO) end-functionalized with triethoxy silyl groups and, tetraethylorthosilicate (TEOS) under basic conditions met with only partial success. The films obtained had low mechanical stability. In contrast, films with good mechanical stability were obtained when the TEOS was replaced with tritanium tetraisopropoxide (TIOPR). The microstructure of the TIOPR/PTMO hybrid synthesized under near neutral conditions was generally similar to the acid catalyzed PTMO/TIOPR hybrids. In another closely related study, the effect of subjecting acid catalyzed hybrid materials to aqueous and basic solutions was examined. Two chemically different systems were chosen which were namely the PTMO-TEOS system and the PTMO-TIOPR system. In addition to the difference in the reactivity between the TEOS and TIOPR, another point of differentiation was the relative solubility of the silicon oxide in basic aqueous solutions in contrast to the relative insolubility of the titanium oxide species in all but the very concentrated basic solutions. An application of the hybrid materials in the area of abrasion resistant coatings was also studied. The effects of the various organic structures on abrasion resistance, the extent of reaction and the mechanism of abrasion was examined. Various low molecular weight organics were functionalized triethoxy silyl groups and coated on polycarbonate and cured. They were then subjected to a Taber abrader test. The results showed that all the functionalized organics showed better abrasion resistance than the polycarbonate if sufficiently cured. NMR data showed that the reaction of the functionalized coatings was limited by vitrification and the extent of reaction was influenced by the basicity of the organic backbone. SEM observations of the abraded surfaces showed that the polycarbonate was abraded by a mechanism different from the functionalized coatings.

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

    DOE Patents [OSTI]

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

    2014-08-19T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    2014-12-22T23:59:59.000Z

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

  13. Method for acid oxidation of radioactive, hazardous, and mixed organic waste materials

    DOE Patents [OSTI]

    Pierce, Robert A. (Aiken, SC); Smith, James R. (Corrales, NM); Ramsey, William G. (Aiken, SC); Cicero-Herman, Connie A. (Aiken, SC); Bickford, Dennis F. (Folly Beach, SC)

    1999-01-01T23:59:59.000Z

    The present invention is directed to a process for reducing the volume of low level radioactive and mixed waste to enable the waste to be more economically stored in a suitable repository, and for placing the waste into a form suitable for permanent disposal. The invention involves a process for preparing radioactive, hazardous, or mixed waste for storage by contacting the waste starting material containing at least one organic carbon-containing compound and at least one radioactive or hazardous waste component with nitric acid and phosphoric acid simultaneously at a contacting temperature in the range of about 140.degree. C. to about 210 .degree. C. for a period of time sufficient to oxidize at least a portion of the organic carbon-containing compound to gaseous products, thereby producing a residual concentrated waste product containing substantially all of said radioactive or inorganic hazardous waste component; and immobilizing the residual concentrated waste product in a solid phosphate-based ceramic or glass form.

  14. Role of minerals in thermal alteration of organic matter. II. A material balance

    SciTech Connect (OSTI)

    Tannenbaum, E.; Huizinga, B.J.; Kaplan, I.R.

    1986-09-01T23:59:59.000Z

    Pyrolysis experiments were performed on Green River and Monterey Formation kerogens (Types I and II, respectively) with and without calcite, illite, or montmorillonite at 300/sup 0/C for 2 to 1000 hours under dry and hydrous conditions. Pyrolysis products were identified and quantified, and a material balance of product and reactants resulted. Applying the results to maturation of organic matter in natural environments, they suggest that a given type of organic matter associated with different minerals in source rocks will yield different products. Furthermore, the different adsorption capacities of minerals exert a significant influence on the migration of polar and high molecular weight compounds generated from the breakdown of kerogen. Therefore, the overall accumulated products from carbonate source rocks are mainly heavy oils with some gas, whereas light oils and gases are the main products from source rocks that contain expandable clays with catalytic and adsorptive properties. 8 figures, 2 tables.

  15. Optical temperature indicator using thermochromic semiconductors

    DOE Patents [OSTI]

    Kronberg, J.W.

    1995-01-01T23:59:59.000Z

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

  16. Optical temperature sensor using thermochromic semiconductors

    DOE Patents [OSTI]

    Kronberg, James W. (Aiken, SC)

    1998-01-01T23:59:59.000Z

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

  17. Optical temperature sensor using thermochromic semiconductors

    DOE Patents [OSTI]

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

    1996-01-01T23:59:59.000Z

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

  18. Optical temperature indicator using thermochromic semiconductors

    DOE Patents [OSTI]

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

    1996-01-01T23:59:59.000Z

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

  19. Optical temperature sensor using thermochromic semiconductors

    DOE Patents [OSTI]

    Kronberg, J.W.

    1996-08-20T23:59:59.000Z

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

  20. Optical temperature sensor using thermochromic semiconductors

    DOE Patents [OSTI]

    Kronberg, J.W.

    1998-06-30T23:59:59.000Z

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

  1. Sandia National Laboratories: Light Creation Materials

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

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

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

    SciTech Connect (OSTI)

    Shengbai Zhang and Nancy Ryan Gray

    2009-09-16T23:59:59.000Z

    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.

  3. Wide band gap semiconductor templates

    DOE Patents [OSTI]

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

    2010-12-14T23:59:59.000Z

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

  4. Failure of the Shockley-Haynes Mobility Experiment with organic semiconducting materials

    E-Print Network [OSTI]

    Boehme, Hollis Clyde

    1961-01-01T23:59:59.000Z

    requirements for the degree of NASTER OF SCIENCE August 1961 Major Subjectt Physics PAILUHE OP THE SHOCKLEY-HAYNES MO31LITY EXPERIMENT I/ITH ORGANIC SEMICONDUCTING MATERIALS s nl A rA X W R i 0 0 g A Thesis HOLLIS CLYDE BOEHME Approved... s . ~pa '"e iii List of Tables I. Intro4uotion II. Sample Prepare. tion III. Nobility FEeasurement Attempts IV. Contacts. V. Discussion of Results BlblioEErap?y 16 52 LIST Oy r IQURr', S ~pa e l. Experimental arrangement of Shockley and Haynes...

  5. Optimisation of the material properties of indium tin oxide layers for use in organic photovoltaics

    SciTech Connect (OSTI)

    Doggart, P.; Bristow, N.; Kettle, J., E-mail: j.kettle@bangor.ac.uk [School of Electronic Engineering, Bangor University, Dean St., Bangor, Gwynedd, Wales LL57 1UT (United Kingdom)

    2014-09-14T23:59:59.000Z

    The influence of indium tin oxide [(In{sub 2}O{sub 3}:Sn), ITO] material properties on the output performance of organic photovoltaic (OPV) devices has been modelled and investigated. In particular, the effect of altering carrier concentration (n), thickness (t), and mobility (?{sub e}) in ITO films and their impact on the optical performance, parasitic resistances and overall efficiency in OPVs was studied. This enables optimal values of these parameters to be calculated for solar cells made with P3HT:PC{sub 61}BM and PCPDTBT:PC{sub 71}BM active layers. The optimal values of n, t and ?{sub e} are not constant between different OPV active layers and depend on the absorption spectrum of the underlying active layer material system. Consequently, design rules for these optimal values as a function of donor bandgap in bulk-heterojunction active layers have been formulated.

  6. Infrared spectroscopy of novel semiconductors /

    E-Print Network [OSTI]

    Chapler, Brian Caleb

    2014-01-01T23:59:59.000Z

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

  7. Novel room temperature ferromagnetic semiconductors

    E-Print Network [OSTI]

    Gupta, Amita

    2004-01-01T23:59:59.000Z

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

  8. Process for forming shaped group III-V semiconductor nanocrystals, and product formed using process

    DOE Patents [OSTI]

    Alivisatos, A. Paul (Oakland, CA); Peng, Xiaogang (Fayetteville, AR); Manna, Liberato (Palo del Colle, IT)

    2001-01-01T23:59:59.000Z

    A process for the formation of shaped Group III-V semiconductor nanocrystals comprises contacting the semiconductor nanocrystal precursors with a liquid media comprising a binary mixture of phosphorus-containing organic surfactants capable of promoting the growth of either spherical semiconductor nanocrystals or rod-like semiconductor nanocrystals, whereby the shape of the semiconductor nanocrystals formed in said binary mixture of surfactants is controlled by adjusting the ratio of the surfactants in the binary mixture.

  9. Process for forming shaped group II-VI semiconductor nanocrystals, and product formed using process

    DOE Patents [OSTI]

    Alivisatos, A. Paul (Oakland, CA); Peng, Xiaogang (Fayetteville, AR); Manna, Liberato (Palo del Colle, IT)

    2001-01-01T23:59:59.000Z

    A process for the formation of shaped Group II-VI semiconductor nanocrystals comprises contacting the semiconductor nanocrystal precursors with a liquid media comprising a binary mixture of phosphorus-containing organic surfactants capable of promoting the growth of either spherical semiconductor nanocrystals or rod-like semiconductor nanocrystals, whereby the shape of the semiconductor nanocrystals formed in said binary mixture of surfactants is controlled by adjusting the ratio of the surfactants in the binary mixture.

  10. Optical temperature sensor using thermochromic semiconductors

    DOE Patents [OSTI]

    Kronberg, J.W.

    1994-01-01T23:59:59.000Z

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

  11. Formation of helix-containing rods in a hybrid inorganic-organic material

    SciTech Connect (OSTI)

    Yuan Zhanhui [School of Chemistry, Newcastle University, Newcastle upon Tyne NE1 7RU (United Kingdom); Clegg, William, E-mail: w.clegg@ncl.ac.u [School of Chemistry, Newcastle University, Newcastle upon Tyne NE1 7RU (United Kingdom); Attfield, Martin P., E-mail: m.attfield@manchester.ac.u [Centre for Nanoporous Materials, School of Chemistry, University of Manchester, Brunswick Street, Manchester M13 9PL (United Kingdom)

    2009-11-15T23:59:59.000Z

    The novel aluminum ethylenediphosphonate fluoride, [HN(CH{sub 2}CH{sub 2}NH{sub 3}){sub 3}][Al{sub 2}(O{sub 3}PCH{sub 2}CH{sub 2}PO{sub 3}){sub 2}F{sub 2}].H{sub 2}O (1) (monoclinic, P2{sub 1}/n, a=12.145(4) A, b=9.265(3) A, c=20.422(6) A, beta=104.952(4){sup o}, Z=3, R{sub 1}=0.092, wR{sub 2}=0.196) has been synthesized by solvothermal methods in the presence of tris(2-aminoethyl)amine and its structure determined using single microcrystal X-ray diffraction data. Compound 1 is a one-dimensional extended chain structure composed of well-separated anionic [Al{sub 2}(O{sub 3}PCH{sub 2}CH{sub 2}PO{sub 3}){sub 2}F{sub 2}]{sup 4-} rods containing helical chains of corner-shared cis-AlO{sub 4}F{sub 2} octahedra at their core. The charge-compensating tris(2-aminoethyl)ammonium cations separate the anionic [Al{sub 2}(O{sub 3}PCH{sub 2}CH{sub 2}PO{sub 3}){sub 2}F{sub 2}]{sup 4-} rods that contain either left- or right-handed helical chains. The incorporation of the organic components into this hybrid material has aided the adoption of one-dimensionality by the compound and defined the pitch of the helical AlO{sub 4}F chain. - Graphical abstract: Helical chains of corner-shared cis-AlO{sub 4}F{sub 2} octahedra form the core of well-separated anionic [Al{sub 2}(O{sub 3}PCH{sub 2}CH{sub 2}PO{sub 3}){sub 2}F{sub 2}]{sup 4-} rods in the novel hybrid aluminum diphosphonate material, (H{sub 4}tren)[Al{sub 2}(O{sub 3}PCH{sub 2}CH{sub 2}PO{sub 3}){sub 2}F{sub 2}].(H{sub 2}O). The incorporation of the organic components into this hybrid material has aided the adoption of a uni-dimensional structure and a specific structural aspect, the helical pitch, within the resulting material, which indicates the potential of this approach to form particular structural features within hybrid materials.

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

    DOE Patents [OSTI]

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

    2013-08-20T23:59:59.000Z

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

  13. Nuclear magnetic resonance of laser-polarized noble gases in molecules, materials and organisms

    SciTech Connect (OSTI)

    Goodson, Boyd M.

    1999-12-01T23:59:59.000Z

    Conventional nuclear magnetic resonance (NMR) spectroscopy and magnetic resonance imaging (MRI) are fundamentally challenged by the insensitivity that stems from the ordinarily low spin polarization achievable in even the strongest NMR magnets. However, by transferring angular momentum from laser light to electronic and nuclear spins, optical pumping methods can increase the nuclear spin polarization of noble gases by several orders of magnitude, thereby greatly enhancing their NMR sensitivity. This dissertation is primarily concerned with the principles and practice of optically pumped nuclear magnetic resonance (OPNMR). The enormous sensitivity enhancement afforded by optical pumping noble gases can be exploited to permit a variety of novel NMR experiments across many disciplines. Many such experiments are reviewed, including the void-space imaging of organisms and materials, NMR and MRI of living tissues, probing structure and dynamics of molecules in solution and on surfaces, and zero-field NMR and MRI.

  14. Annual report: Purchasing and Materials Management Organization, Sandia National Laboratories, fiscal year 1992

    SciTech Connect (OSTI)

    Zaeh, R.A.

    1993-04-01T23:59:59.000Z

    This report summarizes the purchasing and transportation activities of the Purchasing and Materials Management Organization for Fiscal Year 1992. Activities for both the New Mexico and California locations are included. Topics covered in this report include highlights for fiscal year 1992, personnel, procurements (small business procurements, disadvantaged business procurements, woman-owned business procurements, New Mexico commercial business procurements, Bay area commercial business procurements), commitments by states and foreign countries, and transportation activities. Also listed are the twenty-five commercial contractors receiving the largest dollar commitments, commercial contractors receiving commitments of $1,000 or more, integrated contractor and federal agency commitments of $1,000 or more from Sandia National Laboratories/New Mexico and California, and transportation commitments of $1,000 or more from Sandia National Laboratories/New Mexico and California.

  15. Photovoltaic healing of non-uniformities in semiconductor devices

    DOE Patents [OSTI]

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

    2006-08-29T23:59:59.000Z

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

  16. Catalysts for the hydrodenitrogenation of organic materials and process for the preparation of the catalysts

    DOE Patents [OSTI]

    Laine, R.M.; Hirschon, A.S.; Wilson, R.B. Jr.

    1987-12-29T23:59:59.000Z

    A process is described for the preparation of a multimetallic catalyst for the hydrodenitrogenation of an organic feedstock, which process comprises: (a) forming a precatalyst itself comprising: (1) a first metal compound selected from compounds of nickel, cobalt or mixtures thereof; (2) a second metal compound selected from compounds of chromium, molybdenum, tungsten, or mixtures thereof; and (3) an inorganic support; (b) heating the precatalyst of step (a) with a source of sulfide in a first non-oxidizing gas at a temperature and for a time effective to presulfide the precatalyst; (c) adding in a second non-oxidizing gas to the sulfided precatalyst of step (b) an organometallic transition metal moiety selected from compounds of iridium, rhodium, iron, ruthenium, tungsten or mixtures thereof for a time and at a temperature effective to chemically combine the metal components; and (d) optionally heating the chemically combined catalyst of step (b) in vacuum at a temperature and for a time effective to remove residual volatile organic materials. 12 figs.

  17. Adsorption and desorption of atrazine and deethylatrazine by low organic carbon geologic materials

    SciTech Connect (OSTI)

    Roy, W.R.; Krapac, I.G. [Illinois State Geological Survey, Champaign, IL (United States)

    1994-05-01T23:59:59.000Z

    The adsorption and desorption of atrazine (2-chloro-4-ethylamino-6- isopropylamino-s-triazine) and a primary metabolite, deethylatrazine (2-amino-4-chloro-6-isopropylamino-s-triazine; DEA), by low organic C ({le} 3.3 g kg{sup -1}) materials were measured by batch-equilibrium techniques. The adsorbents were samples of glacial outwash sand, till, and stream sediments. The adsorption of both atrazine and DEA conformed to linear isotherms. The adsorption of atrazine by most of the absorbents yielded apparent K, values that were in excess of those based on surface agricultural soils. Adsorption correlated with only the pH of the sand-water suspensions. The desorption of atrazine was hysteretic under the conditions of the measurement. DEA had a lower affinity for the same adsorbents; the mean ratio of Kd values of DEA to those of atrazine was 0.37 {+-} 0.20. DEA adsorption did not correlate with organic C, surface area, clay content of the adsorbents, or with the pH of the suspensions. DEA adsorption, unlike atrazine, tended to be reversible. There was a linear relationship between the adsorption constants of atrazine and those of DEA. 40 refs., 8 figs., 3 tabs.

  18. Nitric-phosphoric acid oxidation of solid and liquid organic materials

    SciTech Connect (OSTI)

    Pierce, R.A.; Smith, J.R.; Poprik, D.C.

    1995-02-01T23:59:59.000Z

    Nitric-phosphoric acid oxidation has been developed specifically to address issues that face the Savannah River Site, other defense-related facilities, private industry, and small-volume generators such as university and medical laboratories. Initially tested to destroy and decontaminate SRS solid, Pu-contaminated job-control waste, the technology has also exhibited potential for remediating hazardous and mixed-hazardous waste forms. The process is unique to Savannah River and offers a valuable alternative to other oxidation processes that require extreme temperatures and/or elevated pressures. To address the broad categories of waste, many different organic compounds which represent a cross-section of the waste that must be treated have been successfully oxidized. Materials that have been quantitatively oxidized at atmospheric pressure below 180{degrees}C include neoprene, cellulose, EDTA, tributylphosphate, and nitromethane. More stable compounds such as benzoic acid, polyethylene, oils, and resins have been completely decomposed below 200{degrees}C and 10 psig. The process uses dilute nitric acid in a concentrated phosphoric acid media as the main oxidant for the organic compounds. Phosphoric acid allow nitric acid to be retained in solution well above its normal boiling point. The reaction forms NOx vapors which can be reoxidized and recycled using air and water. The addition of 0.001M Pd(II) reduces CO generation to near 1% of the released carbon gases. The advantages of this process are that it is straightforward, uses relatively inexpensive reagents, operates at relatively low temperature and pressure, and produces final solutions which are compatible with stainless steel equipment. For organic wastes, all carbon, hydrogen, and nitrogen are converted to gaseous products. If interfaced with an acid recovery system which converts NOx back to nitric acid, the net oxidizer would be oxygen from air.

  19. Organic and inorganic hazardous waste stabilization utilizing fossil fuel combustion waste materials

    SciTech Connect (OSTI)

    Netzel, D.A.; Lane, D.C.; Brown, M.A.; Raska, K.A.; Clark, J.A.; Rovani, J.F.

    1993-09-01T23:59:59.000Z

    A laboratory study was conducted at the Western Research Institute to evaluate the ability of innovative clean coal technology (ICCT) waste to stabilize organic and inorganic constituents of hazardous wastes. The four ICCT wastes used in this study were: (1) the Tennessee Valley Authority (TVA) atmospheric fluidized bed combustor (AFBC) waste, (2) the TVA spray dryer waste, (3) the Laramie River Station spray dryer waste, and (4) the Colorado-Ute AFBC waste. Four types of hazardous waste stream materials were obtained and chemically characterized for use in evaluating the ability of the ICCT wastes to stabilize hazardous organic and inorganic wastes. The wastes included an API separator sludge, mixed metal oxide-hydroxide waste, metal-plating sludge, and creosote-contaminated soil. The API separator sludge and creosote-contaminated soil are US Environmental Protection Agency (EPA)-listed hazardous wastes and contain organic contaminants. The mixed metal oxide-hydroxide waste and metal-plating sludge (also an EPA-listed waste) contain high concentrations of heavy metals. The mixed metal oxide-hydroxide waste fails the Toxicity Characteristic Leaching Procedure (TCLP) for cadmium, and the metal-plating sludge fails the TCLP for chromium. To evaluate the ability of the ICCT wastes to stabilize the hazardous wastes, mixtures involving varying amounts of each of the ICCT wastes with each of the hazardous wastes were prepared, allowed to equilibrate, and then leached with deionized, distilled water. The leachates were analyzed for the hazardous constituent(s) of interest using the Toxicity Characteristic Leaching Procedure.

  20. Viscosity of ?-pinene secondary organic material and implications for particle growth and reactivity

    SciTech Connect (OSTI)

    Renbaum-Wolff, Lindsay; Grayson, James W.; Bateman, Adam P.; Kuwata, Mikinori; Sellier, Mathieu; Murray, Benjamin J.; Shilling, John E.; Martin, Scot T.; Bertram, Allan K.

    2013-05-14T23:59:59.000Z

    Particles composed of secondary organic material (SOM) are abundant in the lower troposphere and play important roles in climate, air quality, and health. The viscosity of these particles is a fundamental property that is presently poorly quantified for conditions relevant to the lower troposphere. Using two new techniques, namely a bead-mobility technique and a poke-flow technique, in conjunction with simulations of fluid flow, we measure the viscosity of the watersoluble component of SOM produced by ?-pinene ozonolysis. The viscosity is comparable to that of honey at 90% relative humidity (RH), comparable to that of peanut butter at 70% RH and greater than or comparable to that of bitumen for ? 30% RH, implying that the studied SOM ranges from liquid to semisolid/solid at ambient relative humidities. With the Stokes-Einstein relation, the measured viscosities further imply that the growth and evaporation of SOM by the exchange of organic molecules between the gas and condensed phases may be confined to the surface region when RH ? 30%, suggesting the importance of an adsorption-type mechanism for partitioning in this regime. By comparison, for RH ? 70% partitioning of organic molecules may effectively occur by an absorption mechanism throughout the bulk of the particle. Finally, the net uptake rates of semi-reactive atmospheric oxidants such as O3 are expected to decrease by two to five orders of magnitude for a change in RH from 90% to ? 30% RH, with possible implications for the rates of chemical aging of SOM particles in the atmosphere.

  1. Controlled growth of semiconductor crystals

    DOE Patents [OSTI]

    Bourret-Courchesne, E.D.

    1992-07-21T23:59:59.000Z

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

  2. Controlled growth of semiconductor crystals

    DOE Patents [OSTI]

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

    1992-01-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    2014-09-08T23:59:59.000Z

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

  4. Study of the transport properties of organic semiconductors based on europium diphthalocyanine and bi-tris-phthalocyanine complexes with ortho-bis(oxymethyl)phenyl bridge and based on erbium and europium dinaphthalocyanine complexes

    SciTech Connect (OSTI)

    Belogorokhov, I. A., E-mail: jugqwerty@mail.ru [State Research and Project Institute of Rare-Metal Industry GIREDMET (Russian Federation); Tikhonov, E. V. [Moscow State University (Russian Federation); Dronov, M. A. [Russian Academy of Sciences, Prokhorov General Physics Institute (Russian Federation); Ryabchikov, Yu. V. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Pashkova, N. V.; Kladova, E. I. [State Research and Project Institute of Rare-Metal Industry GIREDMET (Russian Federation); Belogorokhova, L. I.; Tomilova, L. G.; Khokhlov, D. R. [Moscow State University (Russian Federation)

    2011-11-15T23:59:59.000Z

    The transport properties of organic semiconductors based on europium diphthalocyanine and bitris-phthalocyanine complexes with ortho-bis(oxymethyl)phenyl bridge and based on europium and erbium dinaphthalocyanine are studied. The temperature dependences of the dc conductivity for all types of the structures under study are obtained; it is shown that all dependences include two activation portions. For high-temperature portions, the activation energies are determined as 0.85 eV for europium diphthalocyanine with the ortho-bis(oxymethyl)phenyl bridge, 1.135 eV for europium bi-tris-phthalocyanine with the orthobis(oxymethyl)phenyl bridge, 0.98 eV for europium dinaphthalocyanine, and 1.18 eV for erbium dinaphthalocyanine. For the low-temperature activation portion, it is shown that lanthanide ions and their bond with a ligand make the dominant contribution to the conductivity of the structures under study.

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

    E-Print Network [OSTI]

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

    2012-01-01T23:59:59.000Z

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

  6. Unitary lens semiconductor device

    DOE Patents [OSTI]

    Lear, Kevin L. (Albuquerque, NM)

    1997-01-01T23:59:59.000Z

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

  7. Charge Transport in Organic Semiconductors Veaceslav Coropceanu, Jero^me Cornil,, Demetrio A. da Silva Filho, Yoann Olivier, Robert Silbey,# and

    E-Print Network [OSTI]

    Wu, Zhigang

    electrodes in the case of light-emitting diodes or field-effect transistors or generated within the materials

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

    SciTech Connect (OSTI)

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

    2008-08-06T23:59:59.000Z

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

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

    DOE Patents [OSTI]

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

    2009-11-24T23:59:59.000Z

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

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

    DOE Patents [OSTI]

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

    2014-03-04T23:59:59.000Z

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

  11. Graded core/shell semiconductor nanorods and nanorod barcodes

    DOE Patents [OSTI]

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

    2013-03-26T23:59:59.000Z

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

  12. Graded core/shell semiconductor nanorods and nanorod barcodes

    DOE Patents [OSTI]

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

    2010-12-14T23:59:59.000Z

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

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

    DOE Patents [OSTI]

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

    1987-01-01T23:59:59.000Z

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

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

    DOE Patents [OSTI]

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

    2013-05-14T23:59:59.000Z

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

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

    DOE Patents [OSTI]

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

    2011-07-19T23:59:59.000Z

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

  16. Semiconductor Nanocomposites DOI: 10.1002/anie.201100200

    E-Print Network [OSTI]

    Lin, Zhiqun

    Semiconductor Nanocomposites DOI: 10.1002/anie.201100200 Semiconductor Anisotropic Nanocomposites-based organic/inorganic hybrid solar cells (e.g., CP/QD composites) are favorable alternatives to inorganic elegant approach is to chemically tether CPs on the QD surface (i.e., preparing CP­QD nanocomposites

  17. Electron gas grid semiconductor radiation detectors

    DOE Patents [OSTI]

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

    2002-01-01T23:59:59.000Z

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

  18. Resole resin products derived from fractionated organic and aqueous condensates made by fast-pyrolysis of biomass materials

    DOE Patents [OSTI]

    Chum, Helena L. (8448 Allison Ct., Arvada, CO 80005); Black, Stuart K. (4976 Raleigh St., Denver, CO 80212); Diebold, James P. (57 N. Yank Way, Lakewood, CO 80228); Kreibich, Roland E. (4201 S. 344th, Auburn, WA 98001)

    1993-01-01T23:59:59.000Z

    A process for preparing phenol-formaldehyde resole resins by fractionating organic and aqueous condensates made by fast-pyrolysis of biomass materials while using a carrier gas to move feed into a reactor to produce phenolic-containing/neutrals in which portions of the phenol normally contained in said resins are replaced by a phenolic/neutral fractions extract obtained by fractionation.

  19. Resole resin products derived from fractionated organic and aqueous condensates made by fast-pyrolysis of biomass materials

    DOE Patents [OSTI]

    Chum, H.L.; Black, S.K.; Diebold, J.P.; Kreibich, R.E.

    1993-08-10T23:59:59.000Z

    A process for preparing phenol-formaldehyde resole resins by fractionating organic and aqueous condensates made by fast-pyrolysis of biomass materials while using a carrier gas to move feed into a reactor to produce phenolic-containing/neutrals in which portions of the phenol normally contained in said resins are replaced by a phenolic/neutral fractions extract obtained by fractionation.

  20. 2012 ELECTRONIC PROCESSES IN ORGANIC MATERIALS GORDON RESEARCH SEMINAR, JUNE 2-8, 2012

    SciTech Connect (OSTI)

    Eisele, Dorthe

    2012-06-08T23:59:59.000Z

    This meeting focuses on the latest progress and challenges regarding organic electronics devices, artificial light-harvesting systems, and inorganic/organic hybrid nanoscale systems and especially on the synergy between these fields.

  1. Studies of solution-processed organic light-emitting diodes and their materials

    SciTech Connect (OSTI)

    Hellerich, Emily [Ames Laboratory] [Ames Laboratory

    2013-05-15T23:59:59.000Z

    A hitherto unexplored approach is presented in which a small molecule is used as a host to polymer guests in solution-processed OLEDs. We find that the small molecule host results in much more efficient devices than the often-used alternative polymer host when used for the guests presented. It is likely that nano- and microstructural differences between the hosts contribute to the improvements, which highlights some interesting characteristics that can help to better understand the nature of these mixtures. A number of the guests used in this study were newly synthesized benzobisoxazole-based copolymers. New organic copolymers are presented that are based on the chemical structure of benzobisoxazoles, which have been shown in the past to have good electron transporting properties. The novel concept in this publication pertains to a change in the direction of polymerization, also known as the conjugation pathway, which we show increases the emission efficiency. This work highlights a unique and useful property of organic semiconducting materials in that they can be synthesized to create the desired characteristics. Earlier work is described that kick-started in our research group the use of small molecules in solution-processed OLEDs. Originally these devices were to be used in magnetoresistance studies, but the project took a different path when the devices were more efficient than expected. The efficient use of small molecules in solution-processed OLEDs is highlighted, which at the time was not often the case. Also, the important observation of the effect of solvent choice on the resultant film is emphasized, with discussion of the likely cause of these effects. Microcavity OLEDs are introduced in which the transparent anode ITO is replaced with semi-transparent thin silver, which creates an optical cavity within the devices. The goal was to expand a previous work that created an on-chip spectrometer covering wavelengths 493 to 639 nm. In this case, a spin-coated mixed emitting layer (EML) is used, consisting of a polymer and a small molecule that both emit in the near UV and blue. The resulting combined spectra gives a wide band that can be used to create narrow microcavity emission peaks of 373 to 469 nm, depending on the device thickness (i.e. the cavity’s optical length). In the process of this effort, the mixed EML presented interesting complexities that we attempt to explain via simulation and morphology study.

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

    SciTech Connect (OSTI)

    Ozpineci, B.

    2004-01-02T23:59:59.000Z

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

  3. Dry etching method for compound semiconductors

    DOE Patents [OSTI]

    Shul, R.J.; Constantine, C.

    1997-04-29T23:59:59.000Z

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

  4. Dry etching method for compound semiconductors

    DOE Patents [OSTI]

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

    1997-01-01T23:59:59.000Z

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

  5. Interconnected semiconductor devices

    DOE Patents [OSTI]

    Grimmer, Derrick P. (White Bear Lake, MN); Paulson, Kenneth R. (North St. Paul, MN); Gilbert, James R. (St. Paul, MN)

    1990-10-23T23:59:59.000Z

    Semiconductor layer and conductive layer formed on a flexible substrate, divided into individual devices and interconnected with one another in series by interconnection layers and penetrating terminals.

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

    DOE Patents [OSTI]

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

    2013-10-29T23:59:59.000Z

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

  7. Organo luminescent semiconductor nanocrystal probes for biological applications and process for making and using such probes

    DOE Patents [OSTI]

    Weiss, Shimon (Pinole, CA); Bruchez, Jr., Marcel (Albany, CA); Alivisatos, Paul (Oakland, CA)

    2008-01-01T23:59:59.000Z

    A semiconductor nanocrystal compound is described capable of linking to an affinity molecule. The compound comprises (1) a semiconductor nanocrystal capable of emitting electromagnetic radiation and/or absorbing energy, and/or scattering or diffracting electromagnetic radiation--when excited by an electromagnetic radiation source or a particle beam; and (2) an affinity molecule linked to the semiconductor nanocrystal. The semiconductor nanocrystal is linked to an affinity molecule to form a semiconductor nanocrystal probe capable of bonding with a detectable substance. Exposure of the semiconductor nanocrystal to excitation energy will excite the semiconductor nanocrystal causing the emission of electromagnetic radiation. Further described are processes for respectively: making the luminescent semiconductor nanocrystal compound; making the semiconductor nanocrystal probe; and using the probe to determine the presence of a detectable substance in a material.

  8. Band gap engineering at a semiconductor - crystalline oxide interface

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

    Moghadam, Jahangir-Moghadam; Shen, Xuan; Chrysler, Matthew; Ahmadi-Majlan, Kamyar; Su, Dong; Ngai, Joseph H.

    2015-03-01T23:59:59.000Z

    The epitaxial growth of crystalline oxides on semiconductors provides a pathway to introduce new functionalities to semiconductor devices. Key to integrating the functionalities of oxides onto semiconductors is controlling the band alignment at interfaces between the two materials. Here we apply principles of band gap engineering traditionally used at heterojunctions between conventional semiconductors to control the band offset between a single crystalline oxide and a semiconductor. Reactive molecular beam epitaxy is used to realize atomically abrupt and structurally coherent interfaces between SrZrxTi1-xO? and Ge, in which the band gap of the former is enhanced with Zr content x. We presentmore »structural and electrical characterization of SrZrxTi1-xO?-Ge heterojunctions and demonstrate a type-I band offset can be achieved. These results demonstrate that band gap engineering can be exploited to realize functional semiconductor crystalline oxide heterojunctions.« less

  9. Wide-Bandgap Semiconductors

    SciTech Connect (OSTI)

    Chinthavali, M.S.

    2005-11-22T23:59:59.000Z

    With the increase in demand for more efficient, higher-power, and higher-temperature operation of power converters, design engineers face the challenge of increasing the efficiency and power density of converters [1, 2]. Development in power semiconductors is vital for achieving the design goals set by the industry. Silicon (Si) power devices have reached their theoretical limits in terms of higher-temperature and higher-power operation by virtue of the physical properties of the material. To overcome these limitations, research has focused on wide-bandgap materials such as silicon carbide (SiC), gallium nitride (GaN), and diamond because of their superior material advantages such as large bandgap, high thermal conductivity, and high critical breakdown field strength. Diamond is the ultimate material for power devices because of its greater than tenfold improvement in electrical properties compared with silicon; however, it is more suited for higher-voltage (grid level) higher-power applications based on the intrinsic properties of the material [3]. GaN and SiC power devices have similar performance improvements over Si power devices. GaN performs only slightly better than SiC. Both SiC and GaN have processing issues that need to be resolved before they can seriously challenge Si power devices; however, SiC is at a more technically advanced stage than GaN. SiC is considered to be the best transition material for future power devices before high-power diamond device technology matures. Since SiC power devices have lower losses than Si devices, SiC-based power converters are more efficient. With the high-temperature operation capability of SiC, thermal management requirements are reduced; therefore, a smaller heat sink would be sufficient. In addition, since SiC power devices can be switched at higher frequencies, smaller passive components are required in power converters. Smaller heat sinks and passive components result in higher-power-density power converters. With the advent of the use of SiC devices it is imperative that models of these be made available in commercial simulators. This enables power electronic designers to simulate their designs for various test conditions prior to fabrication. To build an accurate transistor-level model of a power electronic system such as an inverter, the first step is to characterize the semiconductor devices that are present in the system. Suitable test beds need to be built for each device to precisely test the devices and obtain relevant data that can be used for modeling. This includes careful characterization of the parasitic elements so as to emulate the test setup as closely as possible in simulations. This report is arranged as follows: Chapter 2--The testing and characterization of several diodes and power switches is presented. Chapter 3--A 55-kW hybrid inverter (Si insulated gate bipolar transistor--SiC Schottky diodes) device models and test results are presented. A detailed description of the various test setups followed by the parameter extraction, modeling, and simulation study of the inverter performance is presented. Chapter 4--A 7.5-kW all-SiC inverter (SiC junction field effect transistors (JFET)--SiC Schottky diodes) was built and tested. The models built in Saber were validated using the test data and the models were used in system applications in the Saber simulator. The simulation results and a comparison of the data from the prototype tests are discussed in this chapter. Chapter 5--The duration test results of devices utilized in buck converters undergoing reliability testing are presented.

  10. 2 www.trnmag.com Technology Research News February 23/March 2, 2005 Process yields semiconductor foam

    E-Print Network [OSTI]

    Ruina, Andy L.

    Wayne State University have made crystalline aerogels -- new semiconductor materials that are very porous, giving them very high surface areas. Unlike conventional aerogels, the researchers' materials

  11. Features of the electric-field distribution in anisotropic semiconductor wafers in a transverse magnetic field

    SciTech Connect (OSTI)

    Filippov, V. V., E-mail: wwfilippow@mail.ru [Lipetsk State Pedagogical University (Russian Federation); Bormontov, E. N. [Voronezh State University (Russian Federation)

    2013-07-15T23:59:59.000Z

    A macroscopic model of the Hall effects and magnetoresistance in anisotropic semiconductor wafers is developed. The results obtained by solving the electrodynamic boundary problem allow the potential and eddy currents in anisotropic semiconductors to be calculated at different current-contact locations, depending on the parameters of the sample material's anisotropy. The results of this study are of great practical importance for investigating the physical properties of anisotropic semiconductors and simulating the electron-transport phenomena in devices based on anisotropic semiconductors.

  12. Heavy atom induced phosphorescence of organic materials using mono- and trifunctional organomercury derivatives

    E-Print Network [OSTI]

    Burress, Charlotte Nicole

    2009-05-15T23:59:59.000Z

    This dissertation focuses on the phosphorescence of organic chromophores using perfluoro-ortho-phenylene mercury (1) and bis(pentafluorophenyl)mercury (2) as external heavy atom effect inducers. To ascertain the suitability of these luminescent...

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

    DOE Patents [OSTI]

    Farha, Omar K; Hupp, Joseph T

    2013-06-25T23:59:59.000Z

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

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

    DOE Patents [OSTI]

    Farha, Omar K.; Hupp, Joseph T.

    2012-09-11T23:59:59.000Z

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

  15. Weathered Diesel oil as a sorptive phase for hydrophobic organic compounds in aquifer materials

    E-Print Network [OSTI]

    Hudson, Rondall James

    1994-01-01T23:59:59.000Z

    The sorptive properties of weathered diesel oil were investigated by conducting miscible displacement experiments with three hydrophobic organic compounds (HOCs), acenapthene, fluorene, and dibenzothiophene, as tracers in columns containing aquifer...

  16. Panoramic view of electrochemical pseudocapacitor and organic solar cell research in molecularly engineered energy materials (MEEM)

    E-Print Network [OSTI]

    2014-01-01T23:59:59.000Z

    al. The State of Organic Solar Cells?A Meta Analysis. Sol.Efficiency in Polymer Solar Cells. Adv. Funct. Mater. 2009,Bulk- Heterojunction Solar Cells. J. Phys. Chem. C 2011,

  17. Assembly of a Bacteriophage-Based Template for the Organization of Materials into Nanoporous Networks

    E-Print Network [OSTI]

    Hammond, Paula T.

    M13 bacteriophages are assembled via a covalent layer-by-layer process to form a highly nanoporous network capable of organizing nanoparticles and acting as a scaffold for templating metal-oxides. The morphological and ...

  18. Weathered Diesel oil as a sorptive phase for hydrophobic organic compounds in aquifer materials 

    E-Print Network [OSTI]

    Hudson, Rondall James

    1994-01-01T23:59:59.000Z

    The sorptive properties of weathered diesel oil were investigated by conducting miscible displacement experiments with three hydrophobic organic compounds (HOCs), acenapthene, fluorene, and dibenzothiophene, as tracers in columns containing aquifer...

  19. Method and apparatus for use of III-nitride wide bandgap semiconductors in optical communications

    DOE Patents [OSTI]

    Hui, Rongqing (Lenexa, KS); Jiang,Hong-Xing (Manhattan, KS); Lin, Jing-Yu (Manhattan, KS)

    2008-03-18T23:59:59.000Z

    The present disclosure relates to the use of III-nitride wide bandgap semiconductor materials for optical communications. In one embodiment, an optical device includes an optical waveguide device fabricated using a III-nitride semiconductor material. The III-nitride semiconductor material provides for an electrically controllable refractive index. The optical waveguide device provides for high speed optical communications in an infrared wavelength region. In one embodiment, an optical amplifier is provided using optical coatings at the facet ends of a waveguide formed of erbium-doped III-nitride semiconductor materials.

  20. Carrier-lifetime-controlled selective etching process for semiconductors using photochemical etching

    DOE Patents [OSTI]

    Ashby, Carol I. H. (Edgewood, NM); Myers, David R. (Albuquerque, NM)

    1992-01-01T23:59:59.000Z

    The minority carrier lifetime is significantly much shorter in semiconductor materials with very high impurity concentrations than it is in semiconductor materials with lower impurity concentration levels. This phenomenon of reduced minority carrier lifetime in semiconductor materials having high impurity concentration is utilized to advantage for permitting highly selective semiconductor material etching to be achieved using a carrier-driven photochemical etching reaction. Various means may be employed for increasing the local impurity concentration level in specific near-surface regions of a semiconductor prior to subjecting the semiconductor material to a carrier-driven photochemical etching reaction. The regions having the localized increased impurity concentration form a self-aligned mask inhibiting photochemical etching at such localized regions while the adjacent regions not having increased impurity concentrations are selectively photochemically etched. Liquid- or gas-phase etching may be performed.

  1. New Materials for Spintronics. | EMSL

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

    Abstract: One of the critical materials needs for the development of spin electronics is diluted magnetic semiconductors (DMS) which retain their ferromagnetism at and...

  2. The Constitution of Highly Reliable Practices: Materializing Communication as Constitutive of Organizing

    E-Print Network [OSTI]

    Spradley, Robert Tyler

    2012-10-19T23:59:59.000Z

    on collective mind, this study uses a practice-based communication approach to examine the material interplay of bodies, objects, and sites using ethnography and grounded theory. In-depth interviews, participant observations, and organizational documents were...

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

    E-Print Network [OSTI]

    Nolte, David D.

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

  4. Organic Spintronics: Influence of Interface Structure and Magnetism...

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

    of organic spintronics. The complexity of the charge and spin transport in organic semiconductors (OS) makes their study extremely challenging. These properties need to be...

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

    DOE Patents [OSTI]

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

    1988-11-08T23:59:59.000Z

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

  6. Semiconductor Engineers in a Global Economy

    E-Print Network [OSTI]

    Brown, Clair; Linden, Greg

    2007-01-01T23:59:59.000Z

    Technology: The Case of Semiconductors. Brookings Institute:Society, Space, and Semiconductors in The Restructuring Ofin the Global Semiconductor Industry. ” California

  7. Synthesis and Characterization of Mesoporous Semiconductors

    E-Print Network [OSTI]

    Kang, Chris Byung-hwa

    2012-01-01T23:59:59.000Z

    Brock, S. L. “Porous semiconductor chalcogenide aerogels. ”Nanostructured Semiconductor. ” J. Am. Chem. Soc. , 127,in mesostructured semiconductors based on the [SnSe 4 ]4-

  8. Semiconductor Nanowires and Nanotubes for Energy Conversion

    E-Print Network [OSTI]

    Fardy, Melissa Anne

    2010-01-01T23:59:59.000Z

    Thermoelectricity in semiconductor nanostructures. Science,splitting using semiconductor electrodes. InternationalChalcogenides, Monographs in Semiconductor Physics, ed. L.S.

  9. Extracting hot carriers from photoexcited semiconductor nanocrystals

    SciTech Connect (OSTI)

    Zhu, Xiaoyang

    2014-12-10T23:59:59.000Z

    This research program addresses a fundamental question related to the use of nanomaterials in solar energy -- namely, whether semiconductor nanocrystals (NCs) can help surpass the efficiency limits, the so-called “Shockley-Queisser” limit, in conventional solar cells. In these cells, absorption of photons with energies above the semiconductor bandgap generates “hot” charge carriers that quickly “cool” to the band edges before they can be utilized to do work; this sets the solar cell efficiency at a limit of ~31%. If instead, all of the energy of the hot carriers could be captured, solar-to-electric power conversion efficiencies could be increased, theoretically, to as high as 66%. A potential route to capture this energy is to utilize semiconductor nanocrystals. In these materials, the quasi-continuous conduction and valence bands of the bulk semiconductor become discretized due to confinement of the charge carriers. Consequently, the energy spacing between the electronic levels can be much larger than the highest phonon frequency of the lattice, creating a “phonon bottleneck” wherein hot-carrier relaxation is possible via slower multiphonon emission. For example, hot-electron lifetimes as long as ~1 ns have been observed in NCs grown by molecular beam epitaxy. In colloidal NCs, long lifetimes have been demonstrated through careful design of the nanocrystal interfaces. Due to their ability to slow electronic relaxation, semiconductor NCs can in principle enable extraction of hot carriers before they cool to the band edges, leading to more efficient solar cells.

  10. Development and Applications Of Photosensitive Device Systems To Studies Of Biological And Organic Materials

    SciTech Connect (OSTI)

    Gruner, Sol

    2012-01-20T23:59:59.000Z

    The primary focus of the grant is the development of new x-ray detectors for biological and materials work at synchrotron sources, especially Pixel Array Detectors (PADs), and the training of students via research applications to problems in biophysics and materials science using novel x-ray methods. This Final Progress Report provides a high-level overview of the most important accomplishments. These major areas of accomplishment include: (1) Development and application of x-ray Pixel Array Detectors; (2) Development and application of methods of high pressure x-ray crystallography as applied to proteins; (3) Studies on the synthesis and structure of novel mesophase materials derived from block co-polymers.

  11. Solution Phase Routes to Functional Nanostructured Materials for Energy Applications

    E-Print Network [OSTI]

    Rauda, Iris Ester

    2012-01-01T23:59:59.000Z

    bridge between the structural complexity of templated porous materials, and the electronic and optical complexity of semiconductor

  12. Semiconductor nanocrystal probes for biological applications and process for making and using such probes

    DOE Patents [OSTI]

    Weiss, Shimon; Bruchez, Marcel; Alivisatos, Paul

    2012-10-16T23:59:59.000Z

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

  13. Semiconductor nanocrystal probes for biological applications and process for making and using such probes

    DOE Patents [OSTI]

    Weiss, Shimon (Pinole, CA); Bruchez, Marcel (Newark, CA); Alivisatos, Paul (Oakland, CA)

    2011-12-06T23:59:59.000Z

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

  14. Semiconductor nanocrystal probes for biological applications and process for making and using such probes

    DOE Patents [OSTI]

    Weiss, Shimon (Pinole, CA); Bruchez, Marcel (Newark, CA); Alivisatos, Paul (Oakland, CA)

    2011-12-20T23:59:59.000Z

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

  15. Semiconductor nanocrystal probes for biological applications and process for making and using such probes

    DOE Patents [OSTI]

    Weiss, Shimon; Bruchez, Marcel; Alivisatos, Paul

    2014-01-28T23:59:59.000Z

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

  16. Total-scattering pair-distribution function of organic material from powder electron diffraction data

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

    Gorelik, Tatiana E.; Billinge, Simon J. L.; Schmidt, Martin U.; Kolb, Ute

    2015-04-01T23:59:59.000Z

    This paper shows for the first time that pair-distribution function analyses can be carried out on organic and organo-metallic compounds from powder electron diffraction data. Different experimental setups are demonstrated, including selected area electron diffraction (SAED) and nanodiffraction in transmission electron microscopy (TEM) or nanodiffraction in scanning transmission electron microscopy (STEM) modes. The methods were demonstrated on organo-metallic complexes (chlorinated and unchlorinated copper-phthalocyanine) and on purely organic compounds (quinacridone). The PDF curves from powder electron diffraction data, called ePDF, are in good agreement with PDF curves determined from X-ray powder data demonstrating that the problems of obtaining kinematical scattering datamore »and avoiding beam-damage of the sample are possible to resolve.« less

  17. Deposition of hole-transport materials in solid-state dye-sensitized solar cells by doctor-blading

    E-Print Network [OSTI]

    McGehee, Michael

    Deposition of hole-transport materials in solid-state dye-sensitized solar cells by doctor Accepted 19 April 2010 Available online xxxx Keywords: Dye-sensitized solar cells Organic semiconductors)-9,90 -spirobifluorene) in solid-state dye-sensitized solar cells. Doctor-blading is a roll

  18. Electronic-carrier-controlled photochemical etching process in semiconductor device fabrication

    DOE Patents [OSTI]

    Ashby, C.I.H.; Myers, D.R.; Vook, F.L.

    1988-06-16T23:59:59.000Z

    An electronic-carrier-controlled photochemical etching process for carrying out patterning and selective removing of material in semiconductor device fabrication includes the steps of selective ion implanting, photochemical dry etching, and thermal annealing, in that order. In the selective ion implanting step, regions of the semiconductor material in a desired pattern are damaged and the remainder of the regions of the material not implanted are left undamaged. The rate of recombination of electrons and holes is increased in the damaged regions of the pattern compared to undamaged regions. In the photochemical dry etching step which follows ion implanting step, the material in the undamaged regions of the semiconductor are removed substantially faster than in the damaged regions representing the pattern, leaving the ion-implanted, damaged regions as raised surface structures on the semiconductor material. After completion of photochemical dry etching step, the thermal annealing step is used to restore the electrical conductivity of the damaged regions of the semiconductor material.

  19. In situ self-assembled organic interface layers for the controlled growth of oligothiophene thin films on ferroelectric Pb(Zr{sub 0.2}Ti{sub 0.8})O{sub 3}

    SciTech Connect (OSTI)

    Milde, P., E-mail: Peter.Milde@iapp.de; Zerweck-Trogisch, U.; Eng, L. M. [Institute of Applied Photophysics, Technische Universität Dresden, D-01062 Dresden (Germany)] [Institute of Applied Photophysics, Technische Universität Dresden, D-01062 Dresden (Germany); Schönfelder, R.; Koitzsch, A. [Institute for Solid State Research, IFW-Dresden, P.O. Box 270116, DE-01171 Dresden (Germany)] [Institute for Solid State Research, IFW-Dresden, P.O. Box 270116, DE-01171 Dresden (Germany); Haubner, K.; Jaehne, E. [Institute of Macromolecular Chemistry and Textile Chemistry, Technische Universität Dresden, D-01062 Dresden (Germany)] [Institute of Macromolecular Chemistry and Textile Chemistry, Technische Universität Dresden, D-01062 Dresden (Germany)

    2013-12-07T23:59:59.000Z

    We introduce an in situ vacuum procedure for the optimal preparation and analysis of self-assembled monolayers (SAMs) as used in organic molecular electronics on ferroelectric lead zirconate titanate (PZT) substrates. Excellent ordering of oligothiophene semiconductor layers is heavily promoted through the presence of an interfacial bi-functional SAM layer that binds to both the oxidic PZT surface and the organic semiconductor molecules. The described method can be extended to other material combinations, featuring a variety of substrate materials and molecular functionalities.

  20. Method for destroying hazardous organics and other combustible materials in a subcritical/supercritical reactor

    DOE Patents [OSTI]

    Janikowski, Stuart K. (Idaho Falls, ID)

    2000-01-01T23:59:59.000Z

    A waste destruction method using a reactor vessel to combust and destroy organic and combustible waste, including the steps of introducing a supply of waste into the reactor vessel, introducing a supply of an oxidant into the reactor vessel to mix with the waste forming a waste and oxidant mixture, introducing a supply of water into the reactor vessel to mix with the waste and oxidant mixture forming a waste, water and oxidant mixture, reciprocatingly compressing the waste, water and oxidant mixture forming a compressed mixture, igniting the compressed mixture forming a exhaust gas, and venting the exhaust gas into the surrounding atmosphere.

  1. Electrocatalytic Materials and Techniques for the Anodic Oxidation of Various Organic Compounds

    SciTech Connect (OSTI)

    Stephen Everett Treimer

    2002-06-27T23:59:59.000Z

    The focus of this thesis was first to characterize and improve the applicability of Fe(III) and Bi(V) doped PbO{sub 2} film electrodes for use in anodic O-transfer reactions of toxic and waste organic compounds, e.g. phenol, aniline, benzene, and naphthalene. Further, they investigated the use of alternative solution/electrode interfacial excitation techniques to enhance the performance of these electrodes for remediation and electrosynthetic applications. Finally, they have attempted to identify a less toxic metal oxide film that may hold promise for future studies in the electrocatalysis and photoelectrocatalysis of O-transfer reactions using metal oxide film electrodes.

  2. Materials Science and Engineering Program Objectives

    E-Print Network [OSTI]

    Lin, Zhiqun

    Materials Science and Engineering Program Objectives Within the scope of the MSE mission, the objectives of the Materials Engineering Program are to produce graduates who: A. practice materials engineering in a broad range of industries including materials production, semiconductors, medical

  3. Novel room temperature ferromagnetic semiconductors

    SciTech Connect (OSTI)

    Gupta, Amita

    2004-11-01T23:59:59.000Z

    Today's information world, bits of data are processed by semiconductor chips, and stored in the magnetic disk drives. But tomorrow's information technology may see magnetism (spin) and semiconductivity (charge) combined in one 'spintronic' device that exploits both charge and 'spin' to carry data (the best of two worlds). Spintronic devices such as spin valve transistors, spin light emitting diodes, non-volatile memory, logic devices, optical isolators and ultra-fast optical switches are some of the areas of interest for introducing the ferromagnetic properties at room temperature in a semiconductor to make it multifunctional. The potential advantages of such spintronic devices will be higher speed, greater efficiency, and better stability at a reduced power consumption. This Thesis contains two main topics: In-depth understanding of magnetism in Mn doped ZnO, and our search and identification of at least six new above room temperature ferromagnetic semiconductors. Both complex doped ZnO based new materials, as well as a number of nonoxides like phosphides, and sulfides suitably doped with Mn or Cu are shown to give rise to ferromagnetism above room temperature. Some of the highlights of this work are discovery of room temperature ferromagnetism in: (1) ZnO:Mn (paper in Nature Materials, Oct issue, 2003); (2) ZnO doped with Cu (containing no magnetic elements in it); (3) GaP doped with Cu (again containing no magnetic elements in it); (4) Enhancement of Magnetization by Cu co-doping in ZnO:Mn; (5) CdS doped with Mn, and a few others not reported in this thesis. We discuss in detail the first observation of ferromagnetism above room temperature in the form of powder, bulk pellets, in 2-3 mu-m thick transparent pulsed laser deposited films of the Mn (<4 at. percent) doped ZnO. High-resolution transmission electron microscopy (HRTEM) and electron energy loss spectroscopy (EELS) spectra recorded from 2 to 200nm areas showed homogeneous distribution of Mn substituting for Zn a 2+ state in the ZnO lattice. Ferromagnetic Resonance (FMR) technique is used to confirm the existence of ferromagnetic ordering at temperatures as high as 425K. The ab initio calculations were found to be consistent with the observation of ferromagnetism arising from fully polarized Mn 2+ state. The key to observed room temperature ferromagnetism in this system is the low temperature processing, which prevents formation of clusters, secondary phases and the host ZnO from becoming n-type. The electronic structure of the same Mn doped ZnO thin films studied using XAS, XES and RIXS, revealed a strong hybridization between Mn 3d and O 2p states, which is an important characteristic of a Dilute magnetic Semiconductor (DMS). It is shown that the various processing conditions like sintering temperature, dopant concentration and the properties of precursors used for making of DMS have a great influence on the final properties. Use of various experimental techniques to verify the physical properties, and to understand the mechanism involved to give rise to ferromagnetism is presented. Methods to improve the magnetic moment in Mn doped ZnO are also described. New promising DMS materials (such as Cu doped ZnO are explored). The demonstrated new capability to fabricate powder, pellets, and thin films of room temperature ferromagnetic semiconductors thus makes possible the realization of a wide range of complex elements for a variety of new multifunctional phenomena related to Spintronic devices as well as magneto-optic components.

  4. Role of minerals in formation of hydrocarbons during pyrolysis of organic matter - a material balance approach

    SciTech Connect (OSTI)

    Tannenbaum, E.; Huizinga, B.J.; Kaplan, I.R.

    1985-02-01T23:59:59.000Z

    Monterey Formation and Green River Formation kerogens (types II and I, respectively) were isolated, mixed with common sedimentary minerals, and pyrolyzed under dry and hydrous conditions for various times and temperatures. Analysis of all the pyrolyses products were conducted to perform a material balance and to infer reaction kinetics and mechanisms. Material balance of the pyrolyses products, in the presence and absence of minerals, reveals that the kerogen degradation results in the formation of bitumen rich in high molecular weight compounds in the initial stages, followed by additional cracking of kerogen and bitumen. However, amount and type of hydrocarbons in the pyrolyses products of kerogen in the presence of montmorillonite are markedly different from those produced by heating kerogen alone or with other minerals. The initial amounts of products in the presence of montmorillonite, and in particular the quantities of low molecular weight hydrocarbons, are higher than those in the presence of illite, calcite, and kerogen alone. The composition of these low molecular weight compounds is dominated by branched hydrocarbons, indicating catalytic cracking via carbonium ion mechanism, which is initiated on acidic sites of the clay. Composition differences are evident also in the distribution of n-alkanes and in the pristane/phytane ratio. The catalytic effect of montmorillonite, however, disappears in the presence of excess water. These differences may have important implications for the composition and quantities of petroleum generated from source rocks with different mineralogies.

  5. Printable semiconductor structures and related methods of making and assembling

    DOE Patents [OSTI]

    Nuzzo, Ralph G. (Champaign, IL); Rogers, John A. (Champaign, IL); Menard, Etienne (Urbana, IL); Lee, Keon Jae (Tokyo, JP); Khang, Dahl-Young (Urbana, IL); Sun, Yugang (Westmont, IL); Meitl, Matthew (Champaign, IL); Zhu, Zhengtao (Rapid City, SD); Ko, Heung Cho (Urbana, IL); Mack, Shawn (Goleta, CA)

    2010-09-21T23:59:59.000Z

    The present invention provides a high yield pathway for the fabrication, transfer and assembly of high quality printable semiconductor elements having selected physical dimensions, shapes, compositions and spatial orientations. The compositions and methods of the present invention provide high precision registered transfer and integration of arrays of microsized and/or nanosized semiconductor structures onto substrates, including large area substrates and/or flexible substrates. In addition, the present invention provides methods of making printable semiconductor elements from low cost bulk materials, such as bulk silicon wafers, and smart-materials processing strategies that enable a versatile and commercially attractive printing-based fabrication platform for making a broad range of functional semiconductor devices.

  6. Printable semiconductor structures and related methods of making and assembling

    DOE Patents [OSTI]

    Nuzzo, Ralph G.; Rogers, John A.; Menard, Etienne; Lee, Keon Jae; Khang; , Dahl-Young; Sun, Yugang; Meitl, Matthew; Zhu, Zhengtao; Ko, Heung Cho; Mack, Shawn

    2013-03-12T23:59:59.000Z

    The present invention provides a high yield pathway for the fabrication, transfer and assembly of high quality printable semiconductor elements having selected physical dimensions, shapes, compositions and spatial orientations. The compositions and methods of the present invention provide high precision registered transfer and integration of arrays of microsized and/or nanosized semiconductor structures onto substrates, including large area substrates and/or flexible substrates. In addition, the present invention provides methods of making printable semiconductor elements from low cost bulk materials, such as bulk silicon wafers, and smart-materials processing strategies that enable a versatile and commercially attractive printing-based fabrication platform for making a broad range of functional semiconductor devices.

  7. Printable semiconductor structures and related methods of making and assembling

    DOE Patents [OSTI]

    Nuzzo, Ralph G. (Champaign, IL); Rogers, John A. (Champaign, IL); Menard, Etienne (Durham, NC); Lee, Keon Jae (Tokyo, JP); Khang, Dahl-Young (Urbana, IL); Sun, Yugang (Westmont, IL); Meitl, Matthew (Raleigh, NC); Zhu, Zhengtao (Rapid City, SD); Ko, Heung Cho (Urbana, IL); Mack, Shawn (Goleta, CA)

    2011-10-18T23:59:59.000Z

    The present invention provides a high yield pathway for the fabrication, transfer and assembly of high quality printable semiconductor elements having selected physical dimensions, shapes, compositions and spatial orientations. The compositions and methods of the present invention provide high precision registered transfer and integration of arrays of microsized and/or nanosized semiconductor structures onto substrates, including large area substrates and/or flexible substrates. In addition, the present invention provides methods of making printable semiconductor elements from low cost bulk materials, such as bulk silicon wafers, and smart-materials processing strategies that enable a versatile and commercially attractive printing-based fabrication platform for making a broad range of functional semiconductor devices.

  8. Mat. Res. Soc. Symp. Proc. Vol. 628 2000 Materials Research Society Hybrid Inorganic/Organic Diblock Copolymers. Nanostructure in Polyhedral Oligomeric

    E-Print Network [OSTI]

    Mather, Patrick T.

    Our main approach to the synthesis and study of hybrid organic/inorganic materials involvesMat. Res. Soc. Symp. Proc. Vol. 628 © 2000 Materials Research Society CC2.6.1 Hybrid Inorganic the synthesis of melt processable, linear hybrid polymers containing pendent inorganic clusters, and allows us

  9. Energy resolution in semiconductor gamma radiation detectors using heterojunctions and methods of use and preparation thereof

    DOE Patents [OSTI]

    Nikolic, Rebecca J.; Conway, Adam M.; Nelson, Art J.; Payne, Stephen A.

    2012-09-04T23:59:59.000Z

    In one embodiment, a system comprises a semiconductor gamma detector material and a hole blocking layer adjacent the gamma detector material, the hole blocking layer resisting passage of holes therethrough. In another embodiment, a system comprises a semiconductor gamma detector material, and an electron blocking layer adjacent the gamma detector material, the electron blocking layer resisting passage of electrons therethrough, wherein the electron blocking layer comprises undoped HgCdTe. In another embodiment, a method comprises forming a hole blocking layer adjacent a semiconductor gamma detector material, the hole blocking layer resisting passage of holes therethrough. Additional systems and methods are also presented.

  10. Quantum Semiconductor Modeling Ansgar Jungel

    E-Print Network [OSTI]

    Jüngel, Ansgar

    Quantum Semiconductor Modeling Ansgar J¨ungel Vienna University of Technology, Austria www.jungel.at.vu Ansgar J¨ungel (TU Wien) Quantum Semiconductor Modeling www.jungel.at.vu 1 / 154 #12;Contents 1 Introduction 2 Semiconductor modeling 3 Microscopic quantum models Density matrices Schr¨odinger models Wigner

  11. Polaron spin current transport in organic semiconductors

    E-Print Network [OSTI]

    Watanabe, Shun; Ando, Kazuya; Kang, Keehoon; Mooser, Sebastian; Vaynzof, Yana; Kurebayashi, Hidekazu; Saitoh, Eiji; Sirringhaus, Henning

    2014-03-16T23:59:59.000Z

    due to unintentional dop- ing and/or thermal injection from the electrodes (see SI sections C and D). The resistivity of the PBTTT film was determined to be 1.8 G? cm. As a result of this high resistivity the PBTTT films provide electrical isolation... of the nonmagnetic metal (NM) layer. The voltage signal for a Ni80Fe20 (10 nm)/PBTTT (40 nm)/Au (40 nm), in which Pt is replaced by Au, significantly decreases (Fig. 2d), and no voltage signals were detected in a Ni80Fe20 (10 nm)/PBTTT (40 nm)/Cu (300 nm) trilayer...

  12. Synthetic Control of Organic Semiconductor Excited States

    E-Print Network [OSTI]

    Clem, Tabitha Ann

    2010-01-01T23:59:59.000Z

    controlled Keithley 236 SMU. References Thompson, B. ;controlled Keithley 236 SMU. References Markov, D. E. ;controlled Keithley 236 SMU. Polymer mobility was measured

  13. Synthetic Control of Organic Semiconductor Excited States

    E-Print Network [OSTI]

    Clem, Tabitha Ann

    2010-01-01T23:59:59.000Z

    Properties and Photovoltaic Performance. Abstract Theproperties, and photovoltaic performance of a small moleculeproperties, and photovoltaic performance of a small molecule

  14. Synthetic Control of Organic Semiconductor Excited States

    E-Print Network [OSTI]

    Clem, Tabitha Ann

    2010-01-01T23:59:59.000Z

    obtained (J sc or short-circuit current density) and thephotocurrent, the short circuit current density in the Pt-

  15. Structural Phase Contrast in Polycrystalline Organic Semiconductor

    E-Print Network [OSTI]

    Peinke, Joachim

    electronics", with devices such as light- emitting diodes, lasers, photovoltaic cells, field-effect transis

  16. Organo luminescent semiconductor nanocrystal probes for biological applications and process for making and using such probes

    DOE Patents [OSTI]

    Weiss, Shimon (Pinole, CA); Bruchez, Jr., Marcel (Albany, CA); Alivisatos, Paul (Oakland, CA)

    2002-01-01T23:59:59.000Z

    A semiconductor nanocrystal compound is described capable of linking to an affinity molecule. The compound comprises (1) a semiconductor nanocrystal capable of emitting electromagnetic radiation and/or absorbing energy, and/or scattering or diffracting electromagnetic radiation--when excited by an electromagnetic radiation source or a particle beam; and (2) at least one linking agent, having a first portion linked to the semiconductor nanocrystal and a second portion capable of linking to an affity molecule. The compound is linked to an affinity molecule to form a semiconductor nanocrystal probe capable of bonding with a detectable substance. Subsequent exposure to excitation energy will excite the semiconductor nanocrystal in he probe, causing the emission of electromagnetic radiation. Further described are processes for respectively: making the semiconductor nanocrystal compound; making the semiconductor nanocrystal probe; and using the probe to determine the presence of a detectable substance in a material.

  17. Organo luminescent semiconductor nanocrystal probes for biological applications and process for making and using such probes

    DOE Patents [OSTI]

    Weiss, Shimon (Pinole, CA); Bruchez, Jr., Marcel (Albany, CA); Alivisatos, Paul (Oakland, CA)

    2004-03-02T23:59:59.000Z

    A semiconductor nanocrystal compound is described capable of linking to an affinity molecule. The compound comprises (1) a semiconductor nanocrystal capable of emitting electromagnetic radiation and/or absorbing energy, and/or scattering or diffracting electromagnetic radiation--when excited by an electromagnetic radiation source or a particle beam; and (2) at least one linking agent, having a first portion linked to the semiconductor nanocrystal and a second portion capable of linking to an affinity molecule. The compound is linked to an affinity molecule to form a semiconductor nanocrystal probe capable of bonding with a detectable substance. Subsequent exposure to excitation energy will excite the semiconductor nanocrystal in the probe, causing the emission of electromagnetic radiation. Further described are processes for respectively: making the semiconductor nanocrystal compound; making the semiconductor nanocrystal probe; and using the probe to determine the presence of a detectable substance in a material.

  18. Organo luminescent semiconductor nanocrystal probes for biological applications and process for making and using such probes

    DOE Patents [OSTI]

    Weiss, Shimon; Bruchez, Jr., Marcel; Alivisatos, Paul

    2005-08-09T23:59:59.000Z

    A semiconductor nanocrystal compound is described capable of linking to an affinity molecule. The compound comprises (1) a semiconductor nanocrystal capable of emitting electromagnetic radiation and/or absorbing energy, and/or scattering or diffracting electromagnetic radiation--when excited by an electromagnetic radiation source or a particle beam; and (2) at least one linking agent, having a first portion linked to the semiconductor nanocrystal and a second portion capable of linking to an affinity molecule. The compound is linked to an affinity molecule to form a semiconductor nanocrystal probe capable of bonding with a detectable substance. Subsequent exposure to excitation energy will excite the semiconductor nanocrystal in the probe causing the emission of electromagnetic radiation. Further described are processes for respectively: making the luminescent semiconductor nanocrystal compound; making the semiconductor nanocrystal probe; and using the probe to determine the presence of a detectable substance in a material.

  19. Organo luminescent semiconductor nanocrystal probes for biological applications and process for making and using such probes

    DOE Patents [OSTI]

    Weiss, Shimon; Bruchez, Jr., Marcel; Alivisatos, Paul

    2006-09-05T23:59:59.000Z

    A semiconductor nanocrystal compound is described capable of linking to an affinity molecule. The compound comprises (1) a semiconductor nanocrystal capable of emitting electromagnetic radiation and/or absorbing energy, and/or scattering or diffracting electromagnetic radiation--when excited by an electromagnetic radiation source or a particle beam; and (2) at least one linking agent, having a first portion linked to the semiconductor nanocrystal and a second portion capable of linking to an affinity molecule. The compound is linked to an affinity molecule to form a semiconductor nanocrystal probe capable of bonding with a detectable substance. subsequent exposure to excitation energy will excite the semiconductor nanocrystal in the probe causing the emission of electromagnetic radiation. Further described are processes for respectively: making the luminescent semiconductor nanocrystal compound; making the semiconductor nanocrystal probe; and using the probe to determine the presence of a detectable substance in a material.

  20. GaTe semiconductor for radiation detection

    DOE Patents [OSTI]

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

    2009-06-23T23:59:59.000Z

    GaTe semiconductor is used as a room-temperature radiation detector. GaTe has useful properties for radiation detectors: ideal bandgap, favorable mobilities, low melting point (no evaporation), non-hygroscopic nature, and availability of high-purity starting materials. The detector can be used, e.g., for detection of illicit nuclear weapons and radiological dispersed devices at ports of entry, in cities, and off shore and for determination of medical isotopes present in a patient.

  1. Scanning probe microscopy studies of semiconductor surfaces

    SciTech Connect (OSTI)

    Weinberg, W.H. [Univ. of California, Santa Barbara, CA (United States)

    1996-10-01T23:59:59.000Z

    Recent work involving atomic force microscopy and scanning tunneling microscopy is discussed which involves strain-induced, self-assembling nanostructures in compound semiconductor materials. Specific examples include one-dimensional quantum wires of InAs grown by MBE on GaAs(001) and zero-dimensional quantum dots of InP grown by MOCVD on InGaP which is lattice matched to GaAs(001).

  2. Kansas Advanced Semiconductor Project

    SciTech Connect (OSTI)

    Baringer, P.; Bean, A.; Bolton, T.; Horton-Smith, G.; Maravin, Y.; Ratra, B.; Stanton, N.; von Toerne, E.; Wilson, G.

    2007-09-21T23:59:59.000Z

    KASP (Kansas Advanced Semiconductor Project) completed the new Layer 0 upgrade for D0, assumed key electronics projects for the US CMS project, finished important new physics measurements with the D0 experiment at Fermilab, made substantial contributions to detector studies for the proposed e+e- international linear collider (ILC), and advanced key initiatives in non-accelerator-based neutrino physics.

  3. Influence of image charge effect on exciton fine structure in an organic-inorganic quantum well material

    SciTech Connect (OSTI)

    Takagi, Hidetsugu; Kunugita, Hideyuki; Ema, Kazuhiro [Department of Physics, Sophia University, 7-1 Kioi-cho, Chiyoda-ku, Tokyo 102-8554 (Japan); Sato, Mikio; Takeoka, Yuko [Department of Materials and Life Sciences, Sophia University, 7-1 Kioi-cho, Chiyoda-ku, Tokyo 102-8554 (Japan)

    2013-12-04T23:59:59.000Z

    We have investigated experimentally excitonic properties in organic-inorganic hybrid multi quantum well crystals, (C{sub 4}H{sub 9}NH{sub 3}){sub 2}PbBr{sub 4} and (C{sub 6}H{sub 5}?C{sub 2}H{sub 4}NH{sub 3}){sub 2}PbBr{sub 4}, by measuring photoluminescence, reflectance, photoluminescence excitation spectra. In these materials, the excitonic binding energies are enhanced not only by quantum confinement effect (QCE) but also by image charge effect (ICE), since the dielectric constant of the barrier layers is much smaller than that of the well layers. By comparing the 1s-exciton and 2s-exciton energies, we have investigated the influence of ICE with regard to the difference of the Bohr radius.

  4. Materials

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes |IsLove Your Home andDisposition | NationalMaterials

  5. Synthesis and Characterization of Mesoporous Semiconductors and Their Energy Applications

    E-Print Network [OSTI]

    Kang, Chris Byung-hwa

    2013-01-01T23:59:59.000Z

    Biomaterials, Ceramics, and Semiconductors. ” Science, 277,I. “Nanostructured Semiconductors Templated by Cholesteryl-Nanostructured Semiconductor. ” J. Am. Chem. Soc. , 127,

  6. A Novel Class of High-TC Ferromagnetic Semiconductors

    E-Print Network [OSTI]

    Shlyk, L. V.

    2008-01-01T23:59:59.000Z

    Diluted magnetic semiconductor or clustering effect? ”,ferromagnetism in semiconductors”, J. Appl. Phys. , inMaking nonmagnetic semiconductors ferromagnetic”, Science,

  7. Magnetization dynamics and spin diffusion in semiconductors and metals

    E-Print Network [OSTI]

    Cywi?ski, ?ukasz

    2007-01-01T23:59:59.000Z

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

  8. MICROSTRUCTURE-PROPERTY RELATIONSHIPS OF A ZINC OXIDE VARISTOR MATERIAL

    E-Print Network [OSTI]

    Williama, Pamela Louise

    2011-01-01T23:59:59.000Z

    RELATIONSHIPS OF A ZINC OXIDE VARISTOR MATERIAL Pamelaresistors, and zinc oxide varistors are semiconductorRELATIONSHIPS OF A ZINC OXIDE VARISTOR MATERIAL CONTENTS

  9. Solution Phase Routes to Functional Nanostructured Materials for Energy Applications

    E-Print Network [OSTI]

    Rauda, Iris Ester

    2012-01-01T23:59:59.000Z

    synthesis of inorganic semiconductor-based nanostructured materials;inorganic materials. 16,35,62?72 In the synthesis, we begin

  10. Topsil Semiconductor Materials AS | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty Edit withTianlin Baxin Hydropower Station Jump to:TiogaTongdaoToolToppan Printing

  11. Thermoelectric power factor in semiconductors with buried epitaxial semimetallic nanoparticles

    E-Print Network [OSTI]

    Bowers, John

    Thermoelectric power factor in semiconductors with buried epitaxial semimetallic nanoparticles J. M, mobility, and Seebeck coefficient of these materials and discuss their potential for use in thermoelectric on thermoelectric materials has focused on the ability of heterostructures and quantum con- finement to increase

  12. Methods of forming semiconductor devices and devices formed using such methods

    DOE Patents [OSTI]

    Fox, Robert V; Rodriguez, Rene G; Pak, Joshua

    2013-05-21T23:59:59.000Z

    Single source precursors are subjected to carbon dioxide to form particles of material. The carbon dioxide may be in a supercritical state. Single source precursors also may be subjected to supercritical fluids other than supercritical carbon dioxide to form particles of material. The methods may be used to form nanoparticles. In some embodiments, the methods are used to form chalcopyrite materials. Devices such as, for example, semiconductor devices may be fabricated that include such particles. Methods of forming semiconductor devices include subjecting single source precursors to carbon dioxide to form particles of semiconductor material, and establishing electrical contact between the particles and an electrode.

  13. Scientists Connect Thermoelectric Materials and Topological Insulators...

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

    that does not occur in normal semiconductors. Thermoelectric materials enable scalable direct conversion of heat to electricity in solid state devices, and have potential for...

  14. Semiconductor radiation detector

    DOE Patents [OSTI]

    Patt, Bradley E. (Sherman Oaks, CA); Iwanczyk, Jan S. (Los Angeles, CA); Tull, Carolyn R. (Orinda, CA); Vilkelis, Gintas (Westlake Village, CA)

    2002-01-01T23:59:59.000Z

    A semiconductor radiation detector is provided to detect x-ray and light photons. The entrance electrode is segmented by using variable doping concentrations. Further, the entrance electrode is physically segmented by inserting n+ regions between p+ regions. The p+ regions and the n+ regions are individually biased. The detector elements can be used in an array, and the p+ regions and the n+ regions can be biased by applying potential at a single point. The back side of the semiconductor radiation detector has an n+ anode for collecting created charges and a number of p+ cathodes. Biased n+ inserts can be placed between the p+ cathodes, and an internal resistor divider can be used to bias the n+ inserts as well as the p+ cathodes. A polysilicon spiral guard can be implemented surrounding the active area of the entrance electrode or surrounding an array of entrance electrodes.

  15. Semiconductor nanocrystals covalently bound to solid inorganic surfaces using self-assembled monolayers

    DOE Patents [OSTI]

    Alivisatos, A.P.; Colvin, V.L.

    1998-05-12T23:59:59.000Z

    Methods are described for attaching semiconductor nanocrystals to solid inorganic surfaces, using self-assembled bifunctional organic monolayers as bridge compounds. Two different techniques are presented. One relies on the formation of self-assembled monolayers on these surfaces. When exposed to solutions of nanocrystals, these bridge compounds bind the crystals and anchor them to the surface. The second technique attaches nanocrystals already coated with bridge compounds to the surfaces. Analyses indicate the presence of quantum confined clusters on the surfaces at the nanolayer level. These materials allow electron spectroscopies to be completed on condensed phase clusters, and represent a first step towards synthesis of an organized assembly of clusters. These new products are also disclosed. 10 figs.

  16. Semiconductor nanocrystals covalently bound to solid inorganic surfaces using self-assembled monolayers

    DOE Patents [OSTI]

    Alivisatos, A. Paul (Berkeley, CA); Colvin, Vicki L. (Berkeley, CA)

    1998-01-01T23:59:59.000Z

    Methods are described for attaching semiconductor nanocrystals to solid inorganic surfaces, using self-assembled bifunctional organic monolayers as bridge compounds. Two different techniques are presented. One relies on the formation of self-assembled monolayers on these surfaces. When exposed to solutions of nanocrystals, these bridge compounds bind the crystals and anchor them to the surface. The second technique attaches nanocrystals already coated with bridge compounds to the surfaces. Analyses indicate the presence of quantum confined clusters on the surfaces at the nanolayer level. These materials allow electron spectroscopies to be completed on condensed phase clusters, and represent a first step towards synthesis of an organized assembly of clusters. These new products are also disclosed.

  17. White organic light-emitting diodes: Status and perspective

    E-Print Network [OSTI]

    Reineke, Sebastian; Lüssem, Björn; Leo, Karl

    2013-01-01T23:59:59.000Z

    White organic light-emitting diodes (OLEDs) are ultra-thin, large-area light sources made from organic semiconductor materials. Over the last decades, much research has been spent on finding the suitable materials to realize highly efficient monochrome and white OLEDs. With their high efficiency, color-tunability, and color-quality, white OLEDs are emerging to become one of the next generation light sources. In this review, we discuss the physics of a variety of device concepts that are introduced to realize white OLEDs based on both polymer and small molecule organic materi als. Owing to the fact that about 80 % of the internally generated photons are trapped within the thin-film layer structure, we put a second focus on reviewing promising concepts for improved light outcoupling.

  18. Semiconductor Ion Implanters

    SciTech Connect (OSTI)

    MacKinnon, Barry A. [Isys, 2727 Walsh Ave., Suite 103, Santa Clara, CA 95051 (United States); Ruffell, John P. [Group 3, LLC, Sunnyvale, CA 94086 (United States)

    2011-06-01T23:59:59.000Z

    In 1953 the Raytheon CK722 transistor was priced at $7.60. Based upon this, an Intel Xeon Quad Core processor containing 820,000,000 transistors should list at $6.2 billion. Particle accelerator technology plays an important part in the remarkable story of why that Intel product can be purchased today for a few hundred dollars. Most people of the mid twentieth century would be astonished at the ubiquity of semiconductors in the products we now buy and use every day. Though relatively expensive in the nineteen fifties they now exist in a wide range of items from high-end multicore microprocessors like the Intel product to disposable items containing 'only' hundreds or thousands like RFID chips and talking greeting cards. This historical development has been fueled by continuous advancement of the several individual technologies involved in the production of semiconductor devices including Ion Implantation and the charged particle beamlines at the heart of implant machines. In the course of its 40 year development, the worldwide implanter industry has reached annual sales levels around $2B, installed thousands of dedicated machines and directly employs thousands of workers. It represents in all these measures, as much and possibly more than any other industrial application of particle accelerator technology. This presentation discusses the history of implanter development. It touches on some of the people involved and on some of the developmental changes and challenges imposed as the requirements of the semiconductor industry evolved.

  19. WWW.MOTOROLA.COM/SEMICONDUCTORS Microcontrollers

    E-Print Network [OSTI]

    Song, Joe

    WWW.MOTOROLA.COM/SEMICONDUCTORS M68HC11 Microcontrollers M68HC11RM/D Rev. 6, 4/2002 M68HC11 Reference Manual FreescaleSemiconductor,I Freescale Semiconductor, Inc. For More Information On This Product, Go to: www.freescale.com nc... #12;FreescaleSemiconductor,I Freescale Semiconductor, Inc. For More

  20. Semiconductor Probes of Light Dark Matter

    E-Print Network [OSTI]

    Peter W. Graham; David E. Kaplan; Surjeet Rajendran; Matthew T. Walters

    2012-11-12T23:59:59.000Z

    Dark matter with mass below about a GeV is essentially unobservable in conventional direct detection experiments. However, newly proposed technology will allow the detection of single electron events in semiconductor materials with significantly lowered thresholds. This would allow detection of dark matter as light as an MeV in mass. Compared to other detection technologies, semiconductors allow enhanced sensitivity because of their low ionization energy around an eV. Such detectors would be particularly sensitive to dark matter with electric and magnetic dipole moments, with a reach many orders of magnitude beyond current bounds. Observable dipole moment interactions can be generated by new particles with masses as great as 1000 TeV, providing a window to scales beyond the reach of current colliders.

  1. Alternative p-doped hole transport material for low operating voltage and high efficiency organic light-emitting diodes

    SciTech Connect (OSTI)

    Murawski, Caroline, E-mail: caroline.murawski@iapp.de; Fuchs, Cornelius; Hofmann, Simone; Leo, Karl [Institut für Angewandte Photophysik, Technische Universität Dresden, George-Bähr-Str. 1, 01062 Dresden (Germany); Gather, Malte C. [Institut für Angewandte Photophysik, Technische Universität Dresden, George-Bähr-Str. 1, 01062 Dresden (Germany); SUPA, School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, KY16 9SS Scotland (United Kingdom)

    2014-09-15T23:59:59.000Z

    We investigate the properties of N,N?-[(Diphenyl-N,N?-bis)9,9,-dimethyl-fluoren-2-yl]-benzidine (BF-DPB) as hole transport material (HTL) in organic light-emitting diodes (OLEDs) and compare BF-DPB to the commonly used HTLs N,N,N?,N?-tetrakis(4-methoxyphenyl)-benzidine (MeO-TPD), 2,2?,7,7?-tetrakis(N,N?-di-p-methylphenylamino)-9,9?-spirobifluorene (Spiro-TTB), and N,N?-di(naphtalene-1-yl)-N,N?-diphenylbenzidine (NPB). The influence of 2,2?-(perfluoronaphthalene-2,6-diylidene)dimalononitrile (F6-TCNNQ p-dopant) concentration in BF-DPB on the operation voltage and efficiency of red and green phosphorescent OLEDs is studied; best results are achieved at 4?wt. % doping. Without any light extraction structure, BF-DPB based red (green) OLEDs achieve a luminous efficacy of 35?.1?lm/W (74?.0?lm/W) at 1000?cd/m{sup 2} and reach a very high brightness of 10?000 cd/m{sup 2} at a very low voltage of 3.2 V (3.1 V). We attribute this exceptionally low driving voltage to the high ionization potential of BF-DPB which enables more efficient hole injection from BF-DPB to the adjacent electron blocking layer. The high efficiency and low driving voltage lead to a significantly lower luminous efficacy roll-off compared to the other compounds and render BF-DPB an excellent HTL material for highly efficient OLEDs.

  2. EMSL - organic materials

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

    of microbial RiPPs and apply it for lanthipeptide discovery. RiPPquest uses genomics to limit search space to the vicinity of RiPP biosynthetic genes and proteomics to...

  3. organic materials | EMSL

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

    of microbial RiPPs and apply it for lanthipeptide discovery. RiPPquest uses genomics to limit search space to the vicinity of RiPP biosynthetic genes and proteomics to...

  4. Low temperature production of large-grain polycrystalline semiconductors

    DOE Patents [OSTI]

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

    2007-04-10T23:59:59.000Z

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

  5. Sandia National Laboratories: compound semiconductor

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

    compound semiconductor Sandia and EMCORE: Solar Photovoltaics, Fiber Optics, MODE, and Energy Efficiency On March 29, 2013, in Concentrating Solar Power, Energy, Partnership,...

  6. Noise and synamics in semiconductor lasers

    E-Print Network [OSTI]

    Rana, Farhan, 1971-

    2003-01-01T23:59:59.000Z

    In this thesis, theoretical and experimental work on the noise and dynamics in continuous wave and mode-locked semiconductor lasers is presented. The main focus is on semiconductor cascade lasers and semiconductor mode-locked ...

  7. Semiconductors: From Manipulated to Managed Trade

    E-Print Network [OSTI]

    Tyson, Laura D'Andrea; Yoffie, David B.

    1991-01-01T23:59:59.000Z

    o f the Japanese semiconductor industry is a sucecsslul aridcommodnv product Ol the semiconductor industry. They are afor maJtini: semiconductors: »nc

  8. Electron vortices in semiconductors devicesa... Kamran Mohsenib

    E-Print Network [OSTI]

    Electron vortices in semiconductors devicesa... Kamran Mohsenib Aerospace Engineering Sciencies; published online 3 October 2005 The hydrodynamic model of electron transport in semiconductors is analyzed vorticity effects. Furthermore, conditions for observation of electron vortices in semiconductor devices

  9. Recent advances in solid-state organic lasers

    E-Print Network [OSTI]

    Chenais, Sébastien; 10.1002/pi.3173

    2011-01-01T23:59:59.000Z

    Organic solid-state lasers are reviewed, with a special emphasis on works published during the last decade. Referring originally to dyes in solid-state polymeric matrices, organic lasers also include the rich family of organic semiconductors, paced by the rapid development of organic light emitting diodes. Organic lasers are broadly tunable coherent sources are potentially compact, convenient and manufactured at low-costs. In this review, we describe the basic photophysics of the materials used as gain media in organic lasers with a specific look at the distinctive feature of dyes and semiconductors. We also outline the laser architectures used in state-of-the-art organic lasers and the performances of these devices with regard to output power, lifetime, and beam quality. A survey of the recent trends in the field is given, highlighting the latest developments in terms of wavelength coverage, wavelength agility, efficiency and compactness, or towards integrated low-cost sources, with a special focus on the gr...

  10. Method for measuring the drift mobility in doped semiconductors

    DOE Patents [OSTI]

    Crandall, R.S.

    1982-03-09T23:59:59.000Z

    A method for measuring the drift mobility of majority carriers in semiconductors consists of measuring the current transient in a Schottky-barrier device following the termination of a forward bias pulse. An example is given using an amorphous silicon hydrogenated material doped with 0.2% phosphorus. The method is particularly useful with material in which the dielectric relaxation time is shorter than the carrier transit time. It is particularly useful in material useful in solar cells. 10 figs.

  11. Method for measuring the drift mobility in doped semiconductors

    DOE Patents [OSTI]

    Crandall, Richard S. (Princeton, NJ)

    1982-01-01T23:59:59.000Z

    A method for measuring the drift mobility of majority carriers in semiconductors consists of measuring the current transient in a Schottky-barrier device following the termination of a forward bias pulse. An example is given using an amorphous silicon hydrogenated material doped with 0.2% phosphorous. The method is particularly useful with material in which the dielectric relaxation time is shorter than the carrier transit time. It is particularly useful in material useful in solar cells.

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

    SciTech Connect (OSTI)

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

    2014-01-07T23:59:59.000Z

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

  13. Climate VISION: Private Sector Initiatives: Semiconductors

    Office of Scientific and Technical Information (OSTI)

    Agreements The U.S. semiconductor industry, represented by the members of the Environmental Protection Agency's PFC ReductionClimate Partnership for the Semiconductor...

  14. Climate VISION: Private Sector Initiatives: Semiconductors: Resources...

    Office of Scientific and Technical Information (OSTI)

    over 100 companies that account for more than 83% of U.S.-based semiconductor production. The SIA provides a forum for domestic semiconductor companies to work collectively...

  15. Characterization of Amorphous Zinc Tin Oxide Semiconductors....

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

    Amorphous Zinc Tin Oxide Semiconductors. Characterization of Amorphous Zinc Tin Oxide Semiconductors. Abstract: Amorphous zinc tin oxide (ZTO) was investigated to determine the...

  16. Opportunities for Wide Bandgap Semiconductor Power Electronics...

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

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

  17. Graphene Produces More Efficient Charge Transport Inside an Organic...

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

    Graphene Produces More Efficient Charge Transport Inside an Organic Semiconductor Friday, January 30, 2015 Graphene, a two dimensional semi-metal made of sp2 hybridized carbon, is...

  18. Physics with isotopically controlled semiconductors

    SciTech Connect (OSTI)

    Haller, E. E., E-mail: eehaller@lbl.gov [University of California at Berkeley, Department of Materials Science and Engineering (United States)

    2010-07-15T23:59:59.000Z

    This paper is based on a tutorial presentation at the International Conference on Defects in Semiconductors (ICDS-25) held in Saint Petersburg, Russia in July 2009. The tutorial focused on a review of recent research involving isotopically controlled semiconductors. Studies with isotopically enriched semiconductor structures experienced a dramatic expansion at the end of the Cold War when significant quantities of enriched isotopes of elements forming semiconductors became available for worldwide collaborations. Isotopes of an element differ in nuclear mass, may have different nuclear spins and undergo different nuclear reactions. Among the latter, the capture of thermal neutrons which can lead to neutron transmutation doping, is the most prominent effect for semiconductors. Experimental and theoretical research exploiting the differences in all the properties has been conducted and will be illustrated with selected examples.

  19. New N-Type Polymers for Organic Photovoltaics: Cooperative Research and Development Final Report, CRADA Number CRD-06-177

    SciTech Connect (OSTI)

    Olson, D.

    2014-08-01T23:59:59.000Z

    This CRADA will develop improved thin film organic solar cells using a new n-type semiconducting polymer. High efficiency photovoltaics (PVs) based on inorganic semiconductors have good efficiencies (up to 30%) but are extremely expensive to manufacture. Organic PV technology has the potential to overcome this problem through the use of high-throughput production methods like reel-to-reel printing on flexible substrates. Unfortunately, today's best organic PVs have only a few percent efficiency, a number that is insufficient for virtually all commercial applications. The limited choice of stable n-type (acceptor) organic semiconductor materials is one of the key factors that prevent the further improvement of organic PVs. TDA Research, Inc. (TDA) previously developed a new class of electron-deficient (n-type) conjugated polymers for use in organic light emitting diodes (OLEDs). During this project TDA in collaboration with the National Renewable Energy Laboratory (NREL) will incorporate these electron-deficient polymers into organic photovoltaics and investigate their performance. TDA Research, Inc. (TDA) is developing new materials and polymers to improve the performance of organic solar cells. Materials being developed at TDA include spin coated transparent conductors, charge injection layers, fullerene derivatives, electron-deficient polymers, and three-phase (fullerene/polythiophene/dye) active layer inks.

  20. Beyond modulation doping: Engineering a semiconductor to be ambipolar, or making an ON-OFF-ON transistor

    SciTech Connect (OSTI)

    Gupta, K. Das, E-mail: kdasgupta@phy.iitb.ac.in [Department of Physics, Indian Institute of Technology Bombay, Mumbai-400076 (India); Croxall, A. F.; Zheng, B.; Sfigakis, F.; Farrer, I.; Nicoll, C. A.; Beere, H. E.; Ritchie, D. A. [Semiconductor Physics Group, Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE (United Kingdom)

    2014-04-24T23:59:59.000Z

    Semiconductors are traditionaly either p-type or n-type, meaning that the mobile charge carriers in them are either 'holes' in the valence band or electrons in the conduction band. Ambipolar conduction implies that the experimenter should be able to populate the same channel with either electrons or holes in a controlled manner. This has been shown to be possible in newer materials like Graphene and some organic semiconductors. 'Ambipolarity' can open up new device possibilities as well as new ways to study fundamental scattering mechanisms in semiconductors. However, achieving this in a conventional high mobility structure like a GaAs-AlGaAs heterostructure/quantum well requires new thinking. It was realized, that to do this modulation doping must be given up and techniques to make an undoped heterostructure conduct, must be developed first. Such structures have been developed by only a few groups worldwide. They are of great interest to low temperature physicists working with Quantum Hall states and mesoscopic/nano structures in the ballistic regime. We discuss the reason behind this interest and the analysis of scattering mechanisms in such structures. Finally very recent experimental success in developing fully gate controlled ambipolar structures where both electron and hole mobilites exceed 1 million cm{sup 2}/Vs at low temperatures (T?1Kelvin) are discussed. Such gated ambipolar structures can be used to analyse scattering mechanisms in ultra-high mobility 2dimensional electron and hole gases in a way that is not possible using other techniques.

  1. Ge-on-Si Integrated Photonics: New Tricks from an Old Semiconductor

    E-Print Network [OSTI]

    Jifeng, Liu

    We review recent progress in Ge active photonic devices for electronic-photonic integration on Si, demonstrating new tricks in optoelectronics from this “old” semiconductor material used for the first transistor more than ...

  2. Rapid synthesis and size control of CuInS2 semi-conductor nanoparticle...

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

    semi-conductor nanoparticles make them attractive materials for use in next-generation photovoltaics. We have prepared CuInS2 nanoparticles from single source precursors via...

  3. Rapid Synthesis and Size Control of CuInS2 Semi-Conductor Nanoparticle...

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

    semi-conductor nanoparticles make them attractive materials for use in next-generation photovoltaics. We have prepared CuInS2 nanoparticles from single source precursors via...

  4. Growth and characterization of mid-infrared phosphide-based semiconductor diode lasers

    E-Print Network [OSTI]

    Chi, Pei-Chun

    2010-01-01T23:59:59.000Z

    A diode laser emitting at mid-infrared wavelength (2~5 pm) is an ideal light source for petrochemical or industrial-important gas sensing. Antimony-based III-V compound semiconductor material is the most prominent pseudomorphic ...

  5. Semiconductor bridge (SCB) igniter

    DOE Patents [OSTI]

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

    1987-01-01T23:59:59.000Z

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

  6. Semiconductor Bridge Cable Test

    SciTech Connect (OSTI)

    KING, TONY L.

    2002-01-01T23:59:59.000Z

    The semiconductor bridge (SCB) is an electroexplosive device used to initiate detonators. A C cable is commonly used to connect the SCB to a firing set. A series of tests were performed to identify smaller, lighter cables for firing single and multiple SCBs. This report provides a description of these tests and their results. It was demonstrated that lower threshold voltages and faster firing times can be achieved by increasing the wire size, which reduces ohmic losses. The RF 100 appears to be a reasonable substitute for C cable when firing single SCBs. This would reduce the cable volume by 68% and the weight by 67% while increasing the threshold voltage by only 22%. In general, RG 58 outperforms twisted pair when firing multiple SCBs in parallel. The RG 58's superior performance is attributed to its larger conductor size.

  7. Reactive codoping of GaAlInP compound semiconductors

    DOE Patents [OSTI]

    Hanna, Mark Cooper (Boulder, CO); Reedy, Robert (Golden, CO)

    2008-02-12T23:59:59.000Z

    A GaAlInP compound semiconductor and a method of producing a GaAlInP compound semiconductor are provided. The apparatus and method comprises a GaAs crystal substrate in a metal organic vapor deposition reactor. Al, Ga, In vapors are prepared by thermally decomposing organometallic compounds. P vapors are prepared by thermally decomposing phospine gas, group II vapors are prepared by thermally decomposing an organometallic group IIA or IIB compound. Group VIB vapors are prepared by thermally decomposing a gaseous compound of group VIB. The Al, Ga, In, P, group II, and group VIB vapors grow a GaAlInP crystal doped with group IIA or IIB and group VIB elements on the substrate wherein the group IIA or IIB and a group VIB vapors produced a codoped GaAlInP compound semiconductor with a group IIA or IIB element serving as a p-type dopant having low group II atomic diffusion.

  8. Photoacoustic measurement of bandgaps of thermoelectric materials

    E-Print Network [OSTI]

    Ni, George (George Wei)

    2014-01-01T23:59:59.000Z

    Thermoelectric materials are a promising class of direct energy conversion materials, usually consisting of highly doped semiconductors. The key to maximizing their thermal to electrical energy conversion lies in optimizing ...

  9. A proposal for Coulomb assisted laser cooling of piezoelectric semiconductors

    SciTech Connect (OSTI)

    Nia, Iman Hassani; Mohseni, Hooman, E-mail: hmohseni@ece.northwestern.edu [Bio-Inspired Sensors and Optoelectronics Laboratory (BISOL), Department of Electrical Engineering, Northwestern University, Evanston, Illinois 60208 (United States)

    2014-07-28T23:59:59.000Z

    Anti-Stokes laser cooling of semiconductors as a compact and vibration-free method is very attractive. While it has achieved significant milestones, increasing its efficiency is highly desirable. The main limitation is the lack of the pristine material quality with high luminescence efficiency. Here, we theoretically demonstrate that the Coulomb interaction among electrons and holes in piezoelectric heterostructures could lead to coherent damping of acoustic phonons; rendering a significantly higher efficiency that leads to the possibility of cooling a broad range of semiconductors.

  10. Controlled Chemical Doping of Semiconductor Nanocrystals Using Redox Buffers

    SciTech Connect (OSTI)

    Engel, Jesse H.; Surendranath, Yogesh; Alivisatos, Paul

    2013-07-09T23:59:59.000Z

    Semiconductor nanocrystal solids are attractive materials for active layers in next-generation optoelectronic devices; however, their efficient implementation has been impeded by the lack of precise control over dopant concentrations. Herein we demonstrate a chemical strategy for the controlled doping of nanocrystal solids under equilibrium conditions. Exposing lead selenide nanocrystal thin films to solutions containing varying proportions of decamethylferrocene and decamethylferrocenium incrementally and reversibly increased the carrier concentration in the solid by 2 orders of magnitude from their native values. This application of redox buffers for controlled doping provides a new method for the precise control of the majority carrier concentration in porous semiconductor thin films.

  11. Organo Luminescent semiconductor nanocrystal probes for biological applications and process for making and using such probes

    DOE Patents [OSTI]

    Weiss, Shimon (Pinole, CA); Bruchez, Jr., Marcel (Albany, CA); Alivisatos, Paul (Oakland, CA)

    1999-01-01T23:59:59.000Z

    A luminescent semiconductor nanocrystal compound is described which is capable of linking to an affinity molecule. The compound comprises (1) a semiconductor nanocrystal capable of emitting electromagnetic radiation (luminescing) in a narrow wavelength band and/or absorbing energy, and/or scattering or diffracting electromagnetic radiation--when excited by an electromagnetic radiation source (of narrow or broad bandwidth) or a particle beam; and (2) at least one linking agent, having a first portion linked to the semiconductor nanocrystal and a second portion capable of linking to an affinity molecule. The luminescent semiconductor nanocrystal compound is linked to an affinity molecule to form an organo luminescent semiconductor nanocrystal probe capable of bonding with a detectable substance in a material being analyzed, and capable of emitting electromagnetic radiation in a narrow wavelength band and/or absorbing, scattering, or diffracting energy when excited by an electromagnetic radiation source (of narrow or broad bandwidth) or a particle beam. The probe is stable to repeated exposure to light in the presence of oxygen and/or other radicals. Further described is a process for making the luminescent semiconductor nanocrystal compound and for making the organo luminescent semiconductor nanocrystal probe comprising the luminescent semiconductor nanocrystal compound linked to an affinity molecule capable of bonding to a detectable substance. A process is also described for using the probe to determine the presence of a detectable substance in a material.

  12. Mathematical Modeling of Semiconductor Devices

    E-Print Network [OSTI]

    Jüngel, Ansgar

    fibers. · Optoelectronic emitters convert an electronic signal into light. Examples are light-emitting diodes (LED) used in displays and indication lambs and semiconductor lasers used in compact disk systems

  13. Modeling the semiconductor industry dynamics

    E-Print Network [OSTI]

    Wu, Kailiang

    2008-01-01T23:59:59.000Z

    The semiconductor industry is an exciting and challenging industry. Strong demand at the application end, plus the high capital intensity and rapid technological innovation in manufacturing, makes it difficult to manage ...

  14. OPTICAL AND DYNAMIC PROPERTIES OF UNDOPED AND DOPED SEMICONDUCTOR NANOSTRUCTURES

    SciTech Connect (OSTI)

    Grant, C D; Zhang, J Z

    2007-09-28T23:59:59.000Z

    This chapter provides an overview of some recent research activities on the study of optical and dynamic properties of semiconductor nanomaterials. The emphasis is on unique aspects of these properties in nanostructures as compared to bulk materials. Linear, including absorption and luminescence, and nonlinear optical as well as dynamic properties of semiconductor nanoparticles are discussed with focus on their dependence on particle size, shape, and surface characteristics. Both doped and undoped semiconductor nanomaterials are highlighted and contrasted to illustrate the use of doping to effectively alter and probe nanomaterial properties. Some emerging applications of optical nanomaterials are discussed towards the end of the chapter, including solar energy conversion, optical sensing of chemicals and biochemicals, solid state lighting, photocatalysis, and photoelectrochemistry.

  15. Coated semiconductor devices for neutron detection

    DOE Patents [OSTI]

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

    2002-01-01T23:59:59.000Z

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

  16. Design and implementation of a continuous improvement framework, focusing on material and information flow, for the manufacturing of organic photovoltaics

    E-Print Network [OSTI]

    Gogineni, Susheel Teja

    2011-01-01T23:59:59.000Z

    Konarka Technologies is an organic photo voltaic solar panel manufacturing startup and is currently in the process of ramping up their production volumes. The MIT team has worked on numerous improvement activities that ...

  17. Universal alignment of hydrogen levels in semiconductors and insulators

    E-Print Network [OSTI]

    Van de Walle, C G

    2006-01-01T23:59:59.000Z

    including nitride semiconductors and transparent oxides.and C. G. Van de Walle, in Hydrogen in SemiconductorsII, Semiconductors and Semimetals Vol. 61, edited by N. H.

  18. Identifying semiconductors by d.c. ionization conductivity

    E-Print Network [OSTI]

    2006-01-01T23:59:59.000Z

    expected from high-Z semiconductor detectors? ,” IEEE Transand binary compound semiconductors and insulators,” J PhysIdentifying Semiconductors by D.C. Ionization Conductivity

  19. Semiconductor Quantum Rods as Single Molecule Fluorescent Biological Labels

    E-Print Network [OSTI]

    2006-01-01T23:59:59.000Z

    Alivisatos, A.P. Semiconductor nanocrystas for biologicalemission from colloidal semiconductor quantum rods. ScienceLight amplification in semiconductor nanocrystals: Quantum

  20. Enhanced Semiconductor Nanocrystal Conductance via Solution Grown Contacts

    E-Print Network [OSTI]

    Sheldon, Matthew T.

    2010-01-01T23:59:59.000Z

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

  1. Isovalent Anion Substitution in Ga-Mn-pnictide Ferromagnetic Semiconductors

    E-Print Network [OSTI]

    Stone, Peter

    2010-01-01T23:59:59.000Z

    63. O. Madelung, Semiconductors - Basic Data, 2nd Ed. (in Laser Annealing of Semiconductors, edited by J. M. PoateProperties of Semiconductors ("Atom" Publ. House, Moscow,

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

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

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

  3. alternative perovskite materials: Topics by E-print Network

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

    rays is used. Photovoltaics currently relies on three technologies. Monocrystalline and polycrystalline cells are silicon-based. Thin-film cells use semi-conductor materials....

  4. alternative materials wascon: Topics by E-print Network

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

    rays is used. Photovoltaics currently relies on three technologies. Monocrystalline and polycrystalline cells are silicon-based. Thin-film cells use semi-conductor materials....

  5. alternative backfill materials: Topics by E-print Network

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

    rays is used. Photovoltaics currently relies on three technologies. Monocrystalline and polycrystalline cells are silicon-based. Thin-film cells use semi-conductor materials....

  6. alternative refractory materials: Topics by E-print Network

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

    rays is used. Photovoltaics currently relies on three technologies. Monocrystalline and polycrystalline cells are silicon-based. Thin-film cells use semi-conductor materials....

  7. alternative starting materials: Topics by E-print Network

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

    rays is used. Photovoltaics currently relies on three technologies. Monocrystalline and polycrystalline cells are silicon-based. Thin-film cells use semi-conductor materials....

  8. alternative target material: Topics by E-print Network

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

    rays is used. Photovoltaics currently relies on three technologies. Monocrystalline and polycrystalline cells are silicon-based. Thin-film cells use semi-conductor materials....

  9. Activation of molecular catalysts using semiconductor quantum dots

    DOE Patents [OSTI]

    Meyer, Thomas J. (Chapel Hill, NC); Sykora, Milan (Los Alamos, NM); Klimov, Victor I. (Los Alamos, NM)

    2011-10-04T23:59:59.000Z

    Photocatalytic materials based on coupling of semiconductor nanocrystalline quantum dots (NQD) and molecular catalysts. These materials have capability to drive or catalyze non-spontaneous chemical reactions in the presence of visible radiation, ultraviolet radiation, or both. The NQD functions in these materials as a light absorber and charge generator. Following light absorption, the NQD activates a molecular catalyst adsorbed on the surface of the NQD via transfer of one or more charges (either electrons or electron-holes) from the NQD to the molecular catalyst. The activated molecular catalyst can then drive a chemical reaction. A photoelectrolytic device that includes such photocatalytic materials is also described.

  10. Impurity gettering in semiconductors

    DOE Patents [OSTI]

    Sopori, B.L.

    1995-06-20T23:59:59.000Z

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

  11. Impurity gettering in semiconductors

    DOE Patents [OSTI]

    Sopori, Bhushan L. (Denver, CO)

    1995-01-01T23:59:59.000Z

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

  12. Spectrally Narrowed Edge Emission from Organic Light-Emitting Diodes: Evidence for Amplified Spontaneous Emission and Mirrorless Lasing

    E-Print Network [OSTI]

    Yun Tian; Zhengqing Gan; Zhaoqun Zhou; Ji-hun Kang; Q-Han Park; David W. Lynch; Joseph Shinar

    2007-01-14T23:59:59.000Z

    p-Conjugated materials, including small molecules and polymers, are attracting substantial attention as novel gain media in semiconductor lasers; they offer many potential advantages not achievable with conventional inorganic semiconductors: simple processing, low cost, easy tuneability of the spectrum, and large-area integration on flexible substrates. Optically pumped lasing action in various small molecular and polymeric p-conjugated materials has been demonstrated using several resonator configurations. However, electrically pumped organic semiconductor lasers, i.e., organic injection or diode lasers, remain elusive, presumably due to various loss mechanisms, e.g., charge (polaron)-induced absorption and metal electrode absorption. Here we report on evidence for amplified spontaneous emission (ASE), also known as mirrorless lasing (i.e., wherein some of the spontaneously emitted photons are amplified by stimulated emission during their propagation) in DC-driven small molecular organic light-emitting diodes (SMOLEDs). The evidence includes a dramatic spectral line narrowing, with a full width at half maximum (FWHM) of only 5 - 10 nm, and optical gain, of the edge-emission from SMOLEDs at room temperature. However, there is no clear indication of threshold behavior associated with this spectral narrowing. Nevertheless, this discovery should pave the way towards the realization of an organic diode laser.

  13. THE REINCARNATION OF INTERSTELLAR DUST: THE IMPORTANCE OF ORGANIC REFRACTORY MATERIAL IN INFRARED SPECTRA OF COMETARY COMAE AND CIRCUMSTELLAR DISKS

    SciTech Connect (OSTI)

    Kimura, Hiroshi, E-mail: hiroshi_kimura@cps-jp.org [Graduate School of Science, Kobe University, c/o CPS (Center for Planetary Science), Chuo-ku Minatojima Minamimachi 7-1-48, Kobe 650-0047 (Japan)] [Graduate School of Science, Kobe University, c/o CPS (Center for Planetary Science), Chuo-ku Minatojima Minamimachi 7-1-48, Kobe 650-0047 (Japan)

    2013-09-20T23:59:59.000Z

    We consider the reincarnation of interstellar dust to be reborn in protoplanetary disks as aggregates consisting of submicron-sized grains with a crystalline or amorphous silicate core and an organic-rich carbonaceous mantle. We find that infrared spectra of reincarnated interstellar dust reproduce emission peaks at correct wavelengths where the peaks were observed in cometary comae, debris disks, and protoplanetary disks if the volume fraction of organic refractory meets the constraints on elemental abundances. We discuss what we can learn from the infrared spectra of reincarnated interstellar dust in cometary comae and circumstellar disks.

  14. Nanostructured materials for hydrogen storage

    DOE Patents [OSTI]

    Williamson, Andrew J. (Pleasanton, CA); Reboredo, Fernando A. (Pleasanton, CA)

    2007-12-04T23:59:59.000Z

    A system for hydrogen storage comprising a porous nano-structured material with hydrogen absorbed on the surfaces of the porous nano-structured material. The system of hydrogen storage comprises absorbing hydrogen on the surfaces of a porous nano-structured semiconductor material.

  15. IEEE TRANSACTIONS ON SEMICONDUCTOR MANUFACTURING, VOL. 17, NO. 3, AUGUST 2004 455 Dynamic Simulation and Optimization of Cu

    E-Print Network [OSTI]

    Rubloff, Gary W.

    , and health (ESH) im- provements in semiconductor technology and manufacturing. DFE plays a special role in the ESH section of the Interna- tional Technology Roadmap for Semiconductors (ITRS) [1], as Manuscript, and analytical framework which can best enable specific advances in ESH areas such as chemical, materials

  16. WOGOGOB-2004 CONFERENCE MATERIALS. Edited by O. Hints & L. Ainsaar During Kukruse (Caradoc) time, light-brown organ-

    E-Print Network [OSTI]

    unknown authors

    ic matter forming oil shale interlayers in calcareous sediments accumulated in the Baltoscandian Basin (Nestor & Einasto 1997). The oil shale is composed of almost equal portions of carbonate, and clayey siliciclastic and organic matter. The existence of a rich and diverse normal marine bottom

  17. First-principles investigation of organic photovoltaic materials C[subscript 60], C[subscript 70], [C[subscript 60

    E-Print Network [OSTI]

    Qian, Xiaofeng

    We present a first-principles investigation of the excited-state properties of electron acceptors in organic photovoltaics including C[subscript 60], C[subscript 70], [6,6]-phenyl-C[subscript 61]-butyric-acid-methyl-ester ...

  18. Apparatus for the etching for semiconductor devices

    SciTech Connect (OSTI)

    Reinberg, A.R.; Steinberg, G.N.

    1983-01-11T23:59:59.000Z

    Apparatus for the etching of semiconductor devices which includes, in combination, an etching chamber containing the semiconductor device to be etched, an electrodeless etching plasma forming chamber having an inlet connected to a source of continuously flowing etching gas and having an outlet connected to said etching chamber in fluid flow communication; a helical inductive resonator coupler for coupling a source of R.F. electrical power into the electrodeless plasma forming chamber for continuously forming etching plasma from the etching gas flowing therethrough; this inductive resonator coupler including a grounded hollow cylinder of electrically conductive material, with a grounded base member at one end; a helically coiled wire conductor concentrically mounted within the cylinder and spaced from the inner walls thereof; the plasma forming chamber being mounted substantially concentrically within the coil, the end of the coil toward the base member being grounded; and an electrical coupling for applying into the coil an R.F. source of electrical power at a position near, but spaced from, the grounded end thereof.

  19. Correlated exciton dynamics in semiconductor nanostructures

    E-Print Network [OSTI]

    Wen, Patrick, Ph. D. Massachusetts Institute of Technology

    2013-01-01T23:59:59.000Z

    The absorption and dissipation of energy in semiconductor nanostructures are often determined by excited electron dynamics. In semiconductors, one fundamentally important electronic state is an exciton, an excited electron ...

  20. JOURNAL OF MATERIALS SCIENCE LETTERS 21, 2002, 251 255 Organic-inorganic sol-gel coating for corrosion protection

    E-Print Network [OSTI]

    Cao, Guozhong

    for corrosion protection of stainless steel T. P. CHOU Department of Materials Science and Engineering, University of Washington, Seattle, WA, USA E-mail: gzcao@u.washington.edu One of the most effective corrosion example. This is the main reason for the durability and corrosion resistance be- havior of this particular

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

    E-Print Network [OSTI]

    Zeng, Li

    2007-01-01T23:59:59.000Z

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

  2. Semiconductor electrode with improved photostability characteristics

    DOE Patents [OSTI]

    Frank, A.J.

    1985-02-19T23:59:59.000Z

    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.

  3. Semiconductor nanocrystal-based phagokinetic tracking

    DOE Patents [OSTI]

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

    2014-11-18T23:59:59.000Z

    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.

  4. Review: Semiconductor Quantum Light Sources

    E-Print Network [OSTI]

    Andrew J Shields

    2007-04-03T23:59:59.000Z

    Lasers and LEDs display a statistical distribution in the number of photons emitted in a given time interval. New applications exploiting the quantum properties of light require sources for which either individual photons, or pairs, are generated in a regulated stream. Here we review recent research on single-photon sources based on the emission of a single semiconductor quantum dot. In just a few years remarkable progress has been made in generating indistinguishable single-photons and entangled photon pairs using such structures. It suggests it may be possible to realise compact, robust, LED-like semiconductor devices for quantum light generation.

  5. Development of New Absorber Materials to Achieve Organic Photovoltaic Commercial Modules with 15% Efficiency and 20 Years Lifetime: Cooperative Research and Development Final Report, CRADA Number CRD-12-498

    SciTech Connect (OSTI)

    Olson, D.

    2014-08-01T23:59:59.000Z

    Under this CRADA the parties will develop intermediates or materials that can be employed as the active layer in dye sensitized solar cells printed polymer systems, or small molecule organic photovoltaics.

  6. Semiconductor films on flexible iridium substrates

    DOE Patents [OSTI]

    Goyal, Amit

    2005-03-29T23:59:59.000Z

    A laminate semiconductor article includes a flexible substrate, an optional biaxially textured oxide buffer system on the flexible substrate, a biaxially textured Ir-based buffer layer on the substrate or the buffer system, and an epitaxial layer of a semiconductor. Ir can serve as a substrate with an epitaxial layer of a semiconductor thereon.

  7. Ion implantation in compound semiconductors for high-performance electronic devices

    SciTech Connect (OSTI)

    Zolper, J.C.; Baca, A.G.; Sherwin, M.E.; Klem, J.F.

    1996-05-01T23:59:59.000Z

    Advanced electronic devices based on compound semiconductors often make use of selective area ion implantation doping or isolation. The implantation processing becomes more complex as the device dimensions are reduced and more complex material systems are employed. The authors review several applications of ion implantation to high performance junction field effect transistors (JFETs) and heterostructure field effect transistors (HFETs) that are based on compound semiconductors, including: GaAs, AlGaAs, InGaP, and AlGaSb.

  8. Organic salts as super-high rate capability materials for lithium-ion batteries Y. Y. Zhang, Y. Y. Sun, S. X. Du, H.-J. Gao, and S. B. Zhang

    E-Print Network [OSTI]

    Gao, Hongjun

    Organic salts as super-high rate capability materials for lithium-ion batteries Y. Y. Zhang, Y. Y of electrode nanomaterials in lithium-ion battery: The effects of surface stress J. Appl. Phys. 112, 103507://apl.aip.org/about/rights_and_permissions #12;Organic salts as super-high rate capability materials for lithium-ion batteries Y. Y. Zhang,1,2 Y

  9. Modeling direct interband tunneling. I. Bulk semiconductors

    SciTech Connect (OSTI)

    Pan, Andrew, E-mail: pandrew@ucla.edu [Department of Electrical Engineering, University of California, Los Angeles, Los Angeles, California 90095 (United States); Chui, Chi On [Department of Electrical Engineering, University of California, Los Angeles, Los Angeles, California 90095 (United States); California NanoSystems Institute, University of California, Los Angeles, Los Angeles, California 90095 (United States)

    2014-08-07T23:59:59.000Z

    Interband tunneling is frequently studied using the semiclassical Kane model, despite uncertainty about its validity. Revisiting the physical basis of this formula, we find that it neglects coupling to other bands and underestimates transverse tunneling. As a result, significant errors can arise at low and high fields for small and large gap materials, respectively. We derive a simple multiband tunneling model to correct these defects analytically without arbitrary parameters. Through extensive comparison with band structure and quantum transport calculations for bulk InGaAs, InAs, and InSb, we probe the accuracy of the Kane and multiband formulas and establish the superiority of the latter. We also show that the nonlocal average electric field should be used when applying either of these models to nonuniform potentials. Our findings are important for efficient analysis and simulation of bulk semiconductor devices involving tunneling.

  10. Pressure-assisted fabrication of organic light emitting diodes with MoO{sub 3} hole-injection layer materials

    SciTech Connect (OSTI)

    Du, J. [The Princeton Institute for the Science and Technology of Materials (PRISM), Princeton, New Jersey 08544 (United States); Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544 (United States); Anye, V. C.; Vodah, E. O. [Department of Materials Science and Engineering, African University of Science and Technology, Abuja, Federal Capital Territory (Nigeria); Tong, T. [The Princeton Institute for the Science and Technology of Materials (PRISM), Princeton, New Jersey 08544 (United States); Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544 (United States); Zebaze Kana, M. G. [Physics Advanced Laboratory, Sheda Science and Technology Complex, Abuja, Federal Capital Territory (Nigeria); Department of Materials Science and Engineering, Kwara State University, Kwara State (Nigeria); Soboyejo, W. O. [The Princeton Institute for the Science and Technology of Materials (PRISM), Princeton, New Jersey 08544 (United States); Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544 (United States); Department of Materials Science and Engineering, African University of Science and Technology, Abuja, Federal Capital Territory (Nigeria)

    2014-06-21T23:59:59.000Z

    In this study, pressures of ?5 to ?8?MPa were applied to organic light emitting diodes containing either evaporated molybdenum trioxide (MoO{sub 3}) or spin-coated poly(3,4-ethylene dioxythiophene) doped with poly(styrene sulphonate) (PEDOT:PSS) hole-injection layers (HILs). The threshold voltages for both devices were reduced by about half, after the application of pressure. Furthermore, in an effort to understand the effects of pressure treatment, finite element simulations were used to study the evolution of surface contact between the HIL and emissive layer (EML) under pressure. The blister area due to interfacial impurities was also calculated. This was shown to reduce by about half, when the applied pressures were between ?5 and 8?MPa. The finite element simulations used Young's modulus measurements of MoO{sub 3} that were measured using the nanoindentation technique. They also incorporated measurements of the adhesion energy between the HIL and EML (measured by force microscopy during atomic force microscopy). Within a fracture mechanics framework, the implications of the results are then discussed for the pressure-assisted fabrication of robust organic electronic devices.

  11. Mechanical scriber for semiconductor devices

    DOE Patents [OSTI]

    Lin, P.T.

    1985-03-05T23:59:59.000Z

    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.

  12. Mechanical scriber for semiconductor devices

    DOE Patents [OSTI]

    Lin, Peter T. (East Brunswick, NJ)

    1985-01-01T23:59:59.000Z

    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.

  13. Selective observation of photo-induced electric fields inside different material components in bulk-heterojunction organic solar cell

    SciTech Connect (OSTI)

    Chen, Xiangyu; Taguchi, Dai; Manaka, Takaaki; Iwamoto, Mitsumasa, E-mail: iwamoto@pe.titech.ac.jp [Department of Physical Electronics, Tokyo Institute of Technology, 2-12-1, S3-33 O-okayama, Meguro-ku, Tokyo 152-8552 (Japan)] [Department of Physical Electronics, Tokyo Institute of Technology, 2-12-1, S3-33 O-okayama, Meguro-ku, Tokyo 152-8552 (Japan)

    2014-01-06T23:59:59.000Z

    By using electric-field-induced optical second-harmonic generation (EFISHG) measurement at two laser wavelengths of 1000?nm and 860?nm, we investigated carrier behavior inside the pentacene and C{sub 60} component of co-deposited pentacene:C{sub 60} bulk-heterojunctions (BHJs) organic solar cells (OSCs). The EFISHG experiments verified the presence of two carrier paths for electrons and holes in BHJs OSCs. That is, two kinds of electric fields pointing in opposite directions are identified as a result of the selectively probing of SHG activation from C{sub 60} and pentacene. Also, under open-circuit conditions, the transient process of the establishment of open-circuit voltage inside the co-deposited layer has been directly probed, in terms of photovoltaic effect. The EFISHG provides an additional promising method to study carrier path of electrons and holes as well as dissociation of excitons in BHJ OSCs.

  14. Dynamic interplay between spin-crossover and host-guest function in a nanoporous metal-organic framework material.

    SciTech Connect (OSTI)

    Southon, P. D.; Liu, L.; Fellows, E. A.; Price, D. J.; Halder, G. J.; Chapman, K. W.; Moubaraki, B.; Murray, K. S.; Letard, J.F.; Kepert, C. J.; Univ. Sydney; Monash Univ.; Universite Bordeaux

    2009-01-01T23:59:59.000Z

    The nanoporous metal-organic framework [Fe(pz)Ni(CN){sub 4}], 1 (where pz is pyrazine), exhibits hysteretic spin-crossover at ambient conditions and is robust to the adsorption and desorption of a wide range of small molecular guests, both gases (N{sub 2}, O{sub 2}, CO{sub 2}) and vapors (methanol, ethanol, acetone, acetonitrile, and toluene). Through the comprehensive analysis of structure, host-guest properties, and spin-crossover behaviors, it is found that this pillared Hofmann system uniquely displays both guest-exchange-induced changes to spin-crossover and spin-crossover-induced changes to host-guest properties, with direct dynamic interplay between these two phenomena. Guest desorption and adsorption cause pronounced changes to the spin-crossover behavior according to a systematic trend in which larger guests stabilize the high-spin state and therefore depress the spin-crossover temperature of the host lattice. When stabilizing the alternate spin state of the host at any given temperature, these processes directly stimulate the spin-crossover process, providing a chemisensing function. Exploitation of the bistability of the host allows the modification of adsorption properties at a fixed temperature through control of the host spin state, with each state shown to display differing chemical affinities to guest sorption. Guest desorption then adsorption, and vice versa, can be used to switch between spin states in the bistable temperature region, adding a guest-dependent memory effect to this system.

  15. Building Structural Complexity in Semiconductor Nanocrystals through Chemical Transformations

    SciTech Connect (OSTI)

    Sadtler, Bryce F

    2009-05-20T23:59:59.000Z

    Methods are presented for synthesizing nanocrystal heterostructures comprised of two semiconductor materials epitaxially attached within individual nanostructures. The chemical transformation of cation exchange, where the cations within the lattice of an ionic nanocrystal are replaced with a different metal ion species, is used to alter the chemical composition at specific regions ofa nanocrystal. Partial cation exchange was performed in cadmium sulfide (CdS) nanorods of well-defined size and shape to examine the spatial organization of materials within the resulting nanocrystal heterostructures. The selectivity for cation exchange to take place at different facets of the nanocrystal plays an important role in determining the resulting morphology of the binary heterostructure. The exchange of copper (I) (Cu+) cations in CdS nanorods occurs preferentially at the ends of the nanorods. Theoretical modeling of epitaxial attachments between different facets of CdS and Cu2S indicate that the selectivity for cation exchange at the ends of the nanorods is a result of the low formation energy of the interfaces produced. During silver (I) (Ag+) cation exchange in CdS nanorods, non-selective nucleation of silver sulfide (Ag2S), followed by partial phase segregation leads to significant changes in the spatial arrangement of CdS and Ag2S regions at the exchange reaction proceeds through the nanocrystal. A well-ordered striped pattern of alternating CdS and Ag2S segments is found at intermediate fractions of exchange. The forces mediating this spontaneous process are a combination of Ostwald ripening to reduce the interfacial area along with a strain-induced repulsive interaction between Ag2S segments. To elucidate why Cu+ and Ag+ cation exchange with CdS nanorods produce different morphologies, models for epitaxial attachments between various facets of CdS with Cu2S or Ag2S lattices were used to calculate interface formation energies. The formation energies indicate the favorability for interface nucleation at different facets of the nanorod and the stability of the interfaces during growth of the secondary material (Cu2S or Ag2S) within the CdS nanocrystal. The physical properties of the CdS-Ag2S and CdS-Cu2S binary nanorods are discussed in terms of the electronic structure of their components and the heterostructure morphology.

  16. Semiconductor with protective surface coating and method of manufacture thereof. [Patent application

    DOE Patents [OSTI]

    Hansen, W.L.; Haller, E.E.

    1980-09-19T23:59:59.000Z

    Passivation of predominantly crystalline semiconductor devices is provided for by a surface coating of sputtered hydrogenated amorphous semiconductor material. Passivation of a radiation detector germanium diode, for example, is realized by sputtering a coating of amorphous germanium onto the etched and quenched diode surface in a low pressure atmosphere of hydrogen and argon. Unlike prior germanium diode semiconductor devices, which must be maintained in vacuum at cryogenic temperatures to avoid deterioration, a diode processed in the described manner may be stored in air at room temperature or otherwise exposed to a variety of environmental conditions. The coating compensates for pre-existing undesirable surface states as well as protecting the semiconductor device against future impregnation with impurities.

  17. Multi-phonon-assisted absorption and emission in semiconductors and its potential for laser refrigeration

    E-Print Network [OSTI]

    Khurgin, Jacob B

    2014-01-01T23:59:59.000Z

    Laser cooling of semiconductors has been an elusive goal for many years, and while attempts to cool the narrow gap semiconductors such as GaAs are yet to succeed, recently, net cooling has been attained in a wider gap CdS. This raises the question of whether wider gap semiconductors with higher phonon energies and stronger electron-phonon coupling are better suitable for laser cooling. In this work we develop a straightforward theory of phonon-assisted absorption and photoluminescence of semiconductors that involves more than one phonon and use to examine wide gap materials, such as GaN and CdS and compare them with GaAs. The results indicate that while strong electron-phonon coupling in both GaN and CdS definitely improves the prospects of laser cooling, large phonon energy in GaN may be a limitation, which makes CdS a better prospect for laser cooling.

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

    E-Print Network [OSTI]

    Pereira, LMC; Wahl, U

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

  19. Multi-phonon-assisted absorption and emission in semiconductors and its potential for laser refrigeration

    SciTech Connect (OSTI)

    Khurgin, Jacob B., E-mail: jakek@jhu.edu [Johns Hopkins University, Baltimore, Maryland 21208 (United States)

    2014-06-02T23:59:59.000Z

    Laser cooling of semiconductors has been an elusive goal for many years, and while attempts to cool the narrow gap semiconductors such as GaAs are yet to succeed, recently, net cooling has been attained in a wider gap CdS. This raises the question of whether wider gap semiconductors with higher phonon energies and stronger electron-phonon coupling are better suitable for laser cooling. In this work, we develop a straightforward theory of phonon-assisted absorption and photoluminescence of semiconductors that involves more than one phonon and use to examine wide gap materials, such as GaN and CdS and compare them with GaAs. The results indicate that while strong electron-phonon coupling in both GaN and CdS definitely improves the prospects of laser cooling, large phonon energy in GaN may be a limitation, which makes CdS a better prospect for laser cooling.

  20. Joining of dissimilar materials

    DOE Patents [OSTI]

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

    2012-10-16T23:59:59.000Z

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

  1. Fabrication of photonic band gap materials

    DOE Patents [OSTI]

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

    2002-01-15T23:59:59.000Z

    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.

  2. Lateral coupled cavity semiconductor laser

    SciTech Connect (OSTI)

    Salzman, J.; Lang, R.; Yariv, A.

    1985-08-01T23:59:59.000Z

    We report the fabrication and operation of a lateral coupled cavity semiconductor laser that consists of two phase-locked parallel lasers of different lengths and with separate electrical contacts. Mode selectivity that results from the interaction between the two supermodes is investigated experimentally. Frequency selectivity and tunability are obtained by controlling the current to each laser separately. Highly stable single mode operation is also demonstrated.

  3. Compound semiconductor optical waveguide switch

    DOE Patents [OSTI]

    Spahn, Olga B.; Sullivan, Charles T.; Garcia, Ernest J.

    2003-06-10T23:59:59.000Z

    An optical waveguide switch is disclosed which is formed from III-V compound semiconductors and which has a moveable optical waveguide with a cantilevered portion that can be bent laterally by an integral electrostatic actuator to route an optical signal (i.e. light) between the moveable optical waveguide and one of a plurality of fixed optical waveguides. A plurality of optical waveguide switches can be formed on a common substrate and interconnected to form an optical switching network.

  4. Routing for analog chip design at NXP semiconductors

    E-Print Network [OSTI]

    Utrecht, Universiteit

    Routing for analog chip design at NXP semiconductors Marjan van den Akker Theo Beelen Rob H.O. Box 80.089 3508 TB Utrecht The Netherlands #12;Routing for analog chip designs at NXP Semiconductors.1 NXP Semiconductors NXP Semiconductors N.V. (Nasdaq: NXPI) is a global semiconductor company and a long

  5. A two-fold interpenetrating 3D metal-organic framework material constructed from helical chains linked via 4,4'-H{sub 2}bpz fragments

    SciTech Connect (OSTI)

    Xie Yiming [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 35002 (China); College of Materials Science and Engineering, Huaqiao University, the Key Laboratory for Functional Materials of Fujian Higher Education, Quanzhou, Fujian 362021 (China); Zhao Zhenguo; Wu Xiaoyuan; Zhang Qisheng; Chen Lijuan; Wang Fei; Chen Shanci [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 35002 (China); Lu Canzhong [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 35002 (China)], E-mail: czlu@fjirsm.ac.cn

    2008-12-15T23:59:59.000Z

    A 3-connected dia-f-type metal-organic framework compound {l_brace}[Ag(L){sub 3/2}H{sub 2}PO{sub 4}]{r_brace}{sub n} (1) has been synthesized by self-assembly of 4,4'-H{sub 2}bpz (L=4,4'-H{sub 2}bpz=3,3',5,5'-tetramethyl-4,4'-bipyrazole) and Ag{sub 4}P{sub 2}O{sub 7} under hydrothermal conditions. It crystallizes in the tetragonal space group I4{sub 1}/acd with a=21.406(4) A, b=21.406(4) A, c=36.298(8) A, Z=32. X-ray single-crystal diffraction reveals that 1 has a three-dimensional framework with an unprecedented alternate left- and right-handed helices structure, featuring a non-uniform two-fold interpenetrated (4.14{sup 2}) net. Photoluminescent investigation reveals that the title compound displays interesting emissions in a wide region, which shows that the title compound may be a good potential candidate as a photoelectric material. - Graphical abstract: A 3-connected dia-f-type metal-organic framework compound [Ag(4,4'-bpz){sub 3/2}H{sub 2}PO{sub 4}] shows unprecedented alternating left- and right-handed helices structure, featuring a non-uniform two-fold interpenetrated (4.14{sup 2}) net.

  6. Characterization of Hydrogen Complex Formation in III-V Semiconductors

    SciTech Connect (OSTI)

    Williams, Michael D.

    2006-09-28T23:59:59.000Z

    Atomic hydrogen has been found to react with some impurity species in semiconductors. Hydrogenation is a methodology for the introduction of atomic hydrogen into the semiconductor for the express purpose of forming complexes within the material. Efforts to develop hydrogenation as an isolation technique for AlGaAs and Si based devices failed to demonstrate its commercial viability. This was due in large measure to the low activation energies of the formed complexes. Recent studies of dopant passivation in long wavelength (0.98 - 1.55?m) materials suggested that for the appropriate choice of dopants much higher activation energies can be obtained. This effort studied the formation of these complexes in InP, This material is extensively used in optoelectronics, i.e., lasers, modulators and detectors. The experimental techniques were general to the extent that the results can be applied to other areas such as sensor technology, photovoltaics and to other material systems. The activation energies for the complexes have been determined and are reported in the scientific literature. The hydrogenation process has been shown by us to have a profound effect on the electronic structure of the materials and was thoroughly investigated. The information obtained will be useful in assessing the long term reliability of device structures fabricated using this phenomenon and in determining new device functionalities.

  7. Optical devices featuring textured semiconductor layers

    DOE Patents [OSTI]

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

    2012-08-07T23:59:59.000Z

    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.

  8. Optical devices featuring textured semiconductor layers

    DOE Patents [OSTI]

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

    2011-10-11T23:59:59.000Z

    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.

  9. Flexible semi-transparent organic spin valve based on bathocuproine

    SciTech Connect (OSTI)

    Sun, Xiangnan; Bedoya-Pinto, Amilcar; Llopis, Roger [CIC nanoGUNE, Tolosa Hiribidea 76, 20018 Donostia San Sebastian (Spain); Casanova, Fèlix; Hueso, Luis E., E-mail: l.hueso@nanogune.eu [CIC nanoGUNE, Tolosa Hiribidea 76, 20018 Donostia San Sebastian (Spain); IKERBASQUE, Basque Foundation for Science, 48011 Bilbao (Spain)

    2014-08-25T23:59:59.000Z

    Organic semiconductors are attractive materials for advanced spintronic applications due to their long spin lifetimes and, simultaneously, their mechanical flexibility. With the aim of combining these advantages in a single device, we report on the fabrication and properties of a mechanically flexible bathocuproine-based spin valve. This organic spin device shows great stability on both electrical and magneto-transport properties upon mechanical bending at different radius (up to r?=?5?mm), while featuring long-lasting endurance (on bending over 50 times). The room-temperature magnetoresistance ratio reaches up to 3.5%, and is notably preserved under air atmosphere. The observation of spin transport at room-temperature, combined with the outstanding mechanical properties and air stability, highlights the potential of bathocuproine-based spin devices towards applications.

  10. Reflection technique for thermal mapping of semiconductors

    DOE Patents [OSTI]

    Walter, Martin J. (Lee, NY)

    1989-06-20T23:59:59.000Z

    Semiconductors may be optically tested for their temperatures by illuminating them with tunable monochromatic electromagnetic radiation and observing the light reflected off of them. A transition point will occur when the wavelength of the light corresponds with the actual band gap energy of the semiconductor. At the transition point, the image of the semiconductor will appreciably darken as the light is transmitted through it, rather than being reflected off of it. The wavelength of the light at the transition point corresponds to the actual band gap energy and the actual temperature of the semiconductor.

  11. 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...

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

    Office of Scientific and Technical Information (OSTI)

    of EPA. The plan describes actions the industry intends to take to achieve its Climate VISION goal by 2010. Read the Semiconductor Industry Association Work Plan (PDF 94...

  13. Climate VISION: Private Sector Initiatives: Semiconductors: Resources...

    Office of Scientific and Technical Information (OSTI)

    to reduce high global warming potential (GWP) greenhouse gas emissions by following a pollution prevention strategy. Today, nearly 80 percent of U.S. semiconductor manufacturers...

  14. Electrical transport properties of (BN)-rich hexagonal (BN)C semiconductor alloys

    SciTech Connect (OSTI)

    Uddin, M. R.; Doan, T. C.; Li, J.; Lin, J. Y.; Jiang, H. X., E-mail: hx.jiang@ttu.edu [Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, TX 79409 (United States); Ziemer, K. S. [Department of Chemical Engineering, Northeastern University, Boston, MA 02115 (United States)

    2014-08-15T23:59:59.000Z

    The layer structured hexagonal boron nitride carbon semiconductor alloys, h-(BN)C, offer the unique abilities of bandgap engineering (from 0 for graphite to ?6.4 eV for h-BN) and electrical conductivity control (from semi-metal for graphite to insulator for undoped h-BN) through alloying and have the potential to complement III-nitride wide bandgap semiconductors and carbon based nanostructured materials. Epilayers of (BN)-rich h-(BN){sub 1-x}(C{sub 2}){sub x} alloys were synthesized by metal-organic chemical vapor deposition (MOCVD) on (0001) sapphire substrates. Hall-effect measurements revealed that homogeneous (BN)-rich h-(BN){sub 1-x}(C{sub 2}){sub x} alloys are naturally n-type. For alloys with x = 0.032, an electron mobility of about 20 cm{sup 2}/Vs at 650?°K was measured. X-ray photoelectron spectroscopy (XPS) was used to determine the chemical composition and analyze chemical bonding states. Both composition and chemical bonding analysis confirm the formation of alloys. XPS results indicate that the carbon concentration in the alloys increases almost linearly with the flow rate of the carbon precursor (propane (C{sub 3}H{sub 8})) employed during the epilayer growth. XPS chemical bonding analysis showed that these MOCVD grown alloys possess more C-N bonds than C-B bonds, which possibly renders the undoped h-(BN){sub 1-x}(C{sub 2}){sub x} alloys n-type and corroborates the Hall-effect measurement results.

  15. Modifying the organic/electrode interface in Organic Solar Cells (OSCs) and improving the efficiency of solution-processed phosphorescent Organic Light-Emitting Diodes (OLEDs)

    SciTech Connect (OSTI)

    Xiao, Teng

    2012-04-27T23:59:59.000Z

    Organic semiconductors devices, such as, organic solar cells (OSCs), organic light-emitting diodes (OLEDs) and organic field-effect transistors (OFETs) have drawn increasing interest in recent decades. As organic materials are flexible, light weight, and potentially low-cost, organic semiconductor devices are considered to be an alternative to their inorganic counterparts. This dissertation will focus mainly on OSCs and OLEDs. As a clean and renewable energy source, the development of OSCs is very promising. Cells with 9.2% power conversion efficiency (PCE) were reported this year, compared to < 8% two years ago. OSCs belong to the so-called third generation solar cells and are still under development. While OLEDs are a more mature and better studied field, with commercial products already launched in the market, there are still several key issues: (1) the cost of OSCs/OLEDs is still high, largely due to the costly manufacturing processes; (2) the efficiency of OSCs/OLEDs needs to be improved; (3) the lifetime of OSCs/OLEDs is not sufficient compared to their inorganic counterparts; (4) the physics models of the behavior of the devices are not satisfactory. All these limitations invoke the demand for new organic materials, improved device architectures, low-cost fabrication methods, and better understanding of device physics. For OSCs, we attempted to improve the PCE by modifying the interlayer between active layer/metal. We found that ethylene glycol (EG) treated poly(3,4-ethylenedioxythiophene): polystyrenesulfonate (PEDOT: PSS) improves hole collection at the metal/polymer interface, furthermore it also affects the growth of the poly(3- hexylthiophene) (P3HT):phenyl-C61-butyric acid methyl ester (PCBM) blends, making the phase segregation more favorable for charge collection. We then studied organic/inorganic tandem cells. We also investigated the effect of a thin LiF layer on the hole-collection of copper phthalocyanine (CuPc)/C70-based small molecular OSCs. A thin LiF layer serves typically as the electron injection layer in OLEDs and electron collection interlayer in the OSCs. However, several reports showed that it can also assist in holeinjection in OLEDs. Here we first demonstrate that it assists hole-collection in OSCs, which is more obvious after air-plasma treatment, and explore this intriguing dual role. For OLEDs, we focus on solution processing methods to fabricate highly efficient phosphorescent OLEDs. First, we investigated OLEDs with a polymer host matrix, and enhanced charge injection by adding hole- and electron-transport materials into the system. We also applied a hole-blocking and electron-transport material to prevent luminescence quenching by the cathode. Finally, we substituted the polymer host by a small molecule, to achieve more efficient solution processed small molecular OLEDs (SMOLEDs); this approach is cost-effective in comparison to the more common vacuum thermal evaporation. All these studies help us to better understand the underlying relationship between the organic semiconductor materials and the OSCs and OLEDs’ performance and will subsequently assist in further enhancing the efficiencies of OSCs and OLEDs. With better efficiency and longer lifetime, the OSCs and OLEDs will be competitive with their inorganic counterparts.

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

    E-Print Network [OSTI]

    Church, George M.

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

  17. Isovalent Anion Substitution in Ga-Mn-pnictide Ferromagnetic Semiconductors

    E-Print Network [OSTI]

    Stone, Peter

    2010-01-01T23:59:59.000Z

    a so-called diluted magnetic semiconductor (DMS). DMSs arein heavily doped magnetic semiconductors as the probabilitythis method to magnetic semiconductors, the 6×6 k·p matrix

  18. Performance of Adaptive DualDropping ILUT Preconditioners in Semiconductor

    E-Print Network [OSTI]

    Zhang, Jun

    Performance of Adaptive Dual­Dropping ILUT Preconditioners in Semiconductor Dopant Diffusion for iterative solution of sparse linear systems arising in semiconductor dopant diffusion modeling resolution, timestep in the adaptive ODE integrator and the problem physics. Key words: semiconductor TCAD

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

    E-Print Network [OSTI]

    Arizona, University of

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

  20. Semiconductor Capabilities in the U.S. and Industrializing Asia

    E-Print Network [OSTI]

    Brown, Clair; Linden, Greg

    2008-01-01T23:59:59.000Z

    data. Table 2: U.S. Semiconductor Engineers By Location,medium-sized U.S. semiconductor companies, which togetherto represent all U.S. semiconductor firms. The total

  1. Thin film studies of planar transition metal complexes 

    E-Print Network [OSTI]

    Whyte, Alex

    2013-06-29T23:59:59.000Z

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

  2. Implications of mercury interactions with band-gap semiconductor oxides

    SciTech Connect (OSTI)

    Granite, E.J.; King, W.P.; Stanko, D.C.; Pennline, H.W.

    2008-09-01T23:59:59.000Z

    Titanium dioxide is a well-known photooxidation catalyst. It will oxidize mercury in the presence of ultraviolet light from the sun and oxygen and/or moisture to form mercuric oxide. Several companies manufacture self-cleaning windows. These windows have a transparent coating of titanium dioxide. The titanium dioxide is capable of destroying organic contaminants in air in the presence of ultraviolet light from the sun, thereby keeping the windows clean. The commercially available self-cleaning windows were used to sequester mercury from oxygen–nitrogen mixtures. Samples of the self-cleaning glass were placed into specially designed photo-reactors in order to study the removal of elemental mercury from oxygen–nitrogen mixtures resembling air. The possibility of removing mercury from ambient air with a self-cleaning glass apparatus is examined. The intensity of 365-nm ultraviolet light was similar to the natural intensity from sunlight in the Pittsburgh region. Passive removal of mercury from the air may represent an option in lieu of, or in addition to, point source clean-up at combustion facilities. There are several common band-gap semiconductor oxide photocatalysts. Sunlight (both the ultraviolet and visible light components) and band-gap semiconductor particles may have a small impact on the global cycle of mercury in the environment. The potential environmental consequences of mercury interactions with band-gap semiconductor oxides are discussed. Heterogeneous photooxidation might impact the global transport of elemental mercury emanating from flue gases.

  3. PROTECTIVE SURFACE COATINGS ON SEMICONDUCTOR NUCLEAR RADIATION DETECTORS

    E-Print Network [OSTI]

    Hansen, W.L.

    2010-01-01T23:59:59.000Z

    ON SEMICONDUCTOR NUCLEAR RADIATION DETECTORS W. L. Hansen,COATINGS ON SEMICONDUCTOR NUCLEAR RADIATION DETECTORS* W. L.the use of germanium nuclear radiation detec­ tors, a new

  4. New ALS Technique Guides IBM in Next-Generation Semiconductor...

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

    New ALS Technique Guides IBM in Next-Generation Semiconductor Development New ALS Technique Guides IBM in Next-Generation Semiconductor Development Print Wednesday, 21 January 2015...

  5. 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...

  6. Engineering Density of States of Earth Abundant Semiconductors...

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

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

  7. advanced semiconductor manufacturing: Topics by E-print Network

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

    Websites Summary: Business and Manufacturing Tohru Ogawa Semiconductor Company Sony Corporation 12;WISE 2000 ContentsContents Paradigm Shift in Semiconductor Business...

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

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

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

  9. Optic probe for semiconductor characterization

    DOE Patents [OSTI]

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

    2008-09-02T23:59:59.000Z

    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).

  10. Crystal structure, optical and thermal studies of a new organic nonlinear optical material: L-Histidinium maleate 1.5-hydrate

    SciTech Connect (OSTI)

    Gonsago, C. Alosious [Department of Physics, A. J. College of Engineering, Chennai 603103 (India)] [Department of Physics, A. J. College of Engineering, Chennai 603103 (India); Albert, Helen Merina [Department of Physics, Sathyabama University, Chennai 600119 (India)] [Department of Physics, Sathyabama University, Chennai 600119 (India); Karthikeyan, J. [Department of Chemistry, Sathyabama University, Chennai 600119 (India)] [Department of Chemistry, Sathyabama University, Chennai 600119 (India); Sagayaraj, P. [Department of Physics, Loyola College, Chennai 600034 (India)] [Department of Physics, Loyola College, Chennai 600034 (India); Pragasam, A. Joseph Arul, E-mail: drjosephsu@gmail.com [Department of Physics, Sathyabama University, Chennai 600119 (India)] [Department of Physics, Sathyabama University, Chennai 600119 (India)

    2012-07-15T23:59:59.000Z

    Highlights: ? L-Histidinium maleate 1.5-hydrate, a new organic crystal has been grown for the first time. ? The crystal structure is reported for the first time (CCDC 845975). ? The crystal belongs to monoclinic system with space group P2{sub 1}, Z = 4, a = 11.4656(7) ?, b = 8.0530(5) ?, c = 14.9705(9) ? and ? = 101.657(2)°. ? The optical absorption study substantiates the complete transparency of the crystal. ? Kurtz powder SHG test confirms the nonlinear property of the crystal. -- Abstract: A new organic nonlinear optical material L-histidinium maleate 1.5-hydrate (LHM) with the molecular formula C{sub 10}H{sub 16}N{sub 3}O{sub 7.5} has been successfully synthesized from aqueous solution by slow solvent evaporation method. The structural characterization of the grown crystal was carried out by single crystal X-ray diffraction at 293(2) K. In the crystal, molecules are linked through inter and intramolecular N-H?O and O-H?O hydrogen bonds, generate edge fused ring motif. The hydrogen bonded motifs are linked to each other to form a three dimensional network. The FT-IR spectroscopy was used to identify the functional groups of the synthesized compound. The optical behavior of the grown crystal was examined by UV–visible spectral analysis, which shows that the optical absorption is almost negligible in the wavelength range 280–1300 nm. The nonlinear optical property was confirmed by the powder technique of Kurtz and Perry. The thermal behavior of the grown crystal was analyzed by thermogravimetric analysis.

  11. Research on the electronic and optical properties of polymer and other organic molecular thin films

    SciTech Connect (OSTI)

    NONE

    1997-02-01T23:59:59.000Z

    The main goal of the work is to find materials and methods of optimization of organic layered electroluminescent cells and to study such properties of polymers and other organic materials that can be used in various opto-electronic devices. The summary of results obtained during the first year of work is presented. They are: (1) the possibility to produce electroluminescent cells using a vacuum deposition photoresist technology for commercial photoresists has been demonstrated; (2) the idea to replace the polyaryl polymers by other polymers with weaker hole conductivity for optimization of electroluminescent cells with ITO-Al electrodes has been suggested. The goal is to obtain amorphous processable thin films of radiative recombination layers in electroluminescent devices; (3) procedures of preparation of high-quality vacuum-deposited poly (p-phenylene) (PPP) films on various substrates have been developed; (4) it was found for the first time that the fluorescence intensity of PPP films depends on the degree of polymerization; (5) the role of interfaces between organic compounds, on one side, and metals or semiconductors, on the other side, has been studied and quenching of the fluorescence caused by semiconductor layer in thin sandwiches has been observed; (6) studies of the dynamics of photoexcitations revealed the exciton self-trapping in quasi-one-dimensional aggregates; and (7) conditions for preparation of highly crystalline fullerene C{sub 60} films by vacuum deposition have been found. Composites of C{sub 60} with conjugated polymers have been prepared.

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

    E-Print Network [OSTI]

    G. L. Klimchitskaya; B. Geyer

    2008-02-26T23:59:59.000Z

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

  13. Department of Materials Science and Engineering University of Maryland, College Park, MD

    E-Print Network [OSTI]

    Rubloff, Gary W.

    for engineering practice #12;Topics Covered: I. Electrical and Optical Properties--Organic Photovoltaics A. Introduction: Organic photovoltaics B. Ohm's law C. Energy bands and energy gaps D. Carrier density in metals and semiconductors E. Optical absorption in semiconductors F. Excitons -- Size, Energy, Dynamics G. PN junction H

  14. Acute toxicity of smoke screen materials to aquatic organisms, white phosphorus-felt, red phosphorus-butyl rubber and SGF No. 2 fog oil. Final report

    SciTech Connect (OSTI)

    Poston, T.M.; McFadden, K.M.; Bean, R.M.; Clark, M.L.; Thomas, B.L.; Killand, B.W.; Prohammer, L.A.; Kalkwarf, D.R.

    1986-04-01T23:59:59.000Z

    The acute toxicity of three obscurants was determined for nine freshwater organisms. The materials tested were white phosphorus-felt smoke, red phosphorus-butyl rubber (RP-BR) smoke, and smoke generator fuel (SGF) No. 2 fog oil (bulk and vaporized). The chemistry of WP-F and RP-BR smoke in water and the resulting effects on aquatic organisms are similar. Combustion of these two obscurants and their deposition in water leads to the formation of many complex oxy-phosphoric acids. Rates of hydrolysis of these complex products to ortho-phosphate were inconsistent and unpredictable over time. These products acidify water and produce toxic effects after exhausting the buffering capacity of the water. Acute 96 hr tests using Daphnia magna with neutralized and nonneutralized exposure solutions indicated that the presence of unidentified toxic component(s) acted independently of pH. At pH levels of 6.0 to 7.0, phosphorus combustion products precipitated out of solution leading to a bimodal toxic response in extended 96-hr tests with Daphnia magna. Most components of fog oil had low solubility in water. Saturation was apparent at approximately 0.1 to 0.3 mg/L total oil. Vaporization had no demonstrable effect on the chemistry or toxicity of the fog oil. Neither the bulk fog oil nor the vaporized fog oil was acutely toxic to freshwater animals at concentrations less than 10 mg/L total oil. In oil-water mixes in excess of 1.0 mg/L total oil, fog oil quickly separated and floated to the surface. The primary hazard associated with vaporized and bulk fog oil was the physical effect of oil fouling the organisms. Photolysis increased the concentration of water-soluble components of the fog oil. Acute toxicity was demonstrated in oil-water mixes (approx.10 mg/L total oil) of photolyzed bulk and vaporized fog oil. No difference in toxicity was observed between photolyzed and non-photolyzed dilutions of OWM at comparable levels of total oil.

  15. Nonlinear Peltier effect in semiconductors Mona Zebarjadia

    E-Print Network [OSTI]

    Nonlinear Peltier effect in semiconductors Mona Zebarjadia Department of Electrical Engineering; published online 18 September 2007 Nonlinear Peltier coefficient of a doped InGaAs semiconductor is calculated numerically using the Monte Carlo technique. The Peltier coefficient is also obtained analytically

  16. Ultra-high speed semiconductor lasers

    SciTech Connect (OSTI)

    Lau, K.Y.; Yariv, A.

    1985-02-01T23:59:59.000Z

    Recent progress on semiconductor lasers having a very high direct modulation bandwidth of beyond 10 GHz are described. Issues related to application of these lasers in actual systems are addressed. Possibilities of further extending the bandwidth of semiconductor lasers are examined.

  17. Stable surface passivation process for compound semiconductors

    DOE Patents [OSTI]

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

    2001-01-01T23:59:59.000Z

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

  18. Hybrid anode for semiconductor radiation detectors

    DOE Patents [OSTI]

    Yang, Ge; Bolotnikov, Aleksey E; Camarda, Guiseppe; Cui, Yonggang; Hossain, Anwar; Kim, Ki Hyun; James, Ralph B

    2013-11-19T23:59:59.000Z

    The present invention relates to a novel hybrid anode configuration for a radiation detector that effectively reduces the edge effect of surface defects on the internal electric field in compound semiconductor detectors by focusing the internal electric field of the detector and redirecting drifting carriers away from the side surfaces of the semiconductor toward the collection electrode(s).

  19. Photosynthesis-inspired device architectures for organic photovoltaics

    E-Print Network [OSTI]

    Heidel, Timothy David

    2010-01-01T23:59:59.000Z

    Organic semiconductor photovoltaics offer a promising route to low-cost, scalable, emissions-free electricity generation. However, achieving higher power conversion efficiencies is critical before these devices can play a ...

  20. Field emission from organic materials

    E-Print Network [OSTI]

    Kymissis, Ioannis, 1977-

    2003-01-01T23:59:59.000Z

    Field emission displays (FEDs) show great promise as high performance flat panel displays. The light emission process is efficient, long lifetimes are possible with high brightness, and bright passive matrix displays can ...

  1. Supporting Organizations | Advanced Materials | ORNL

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

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

  2. Optical Nonlinearities and Ultrafast Carrier Dynamics in Semiconductor Quantum Dots

    SciTech Connect (OSTI)

    Klimov, V.; McBranch, D.; Schwarz, C.

    1998-08-10T23:59:59.000Z

    Low-dimensional semiconductors have attracted great interest due to the potential for tailoring their linear and nonlinear optical properties over a wide-range. Semiconductor nanocrystals (NC's) represent a class of quasi-zero-dimensional objects or quantum dots. Due to quantum cordhement and a large surface-to-volume ratio, the linear and nonlinear optical properties, and the carrier dynamics in NC's are significantly different horn those in bulk materials. napping at surface states can lead to a fast depopulation of quantized states, accompanied by charge separation and generation of local fields which significantly modifies the nonlinear optical response in NC's. 3D carrier confinement also has a drastic effect on the energy relaxation dynamics. In strongly confined NC's, the energy-level spacing can greatly exceed typical phonon energies. This has been expected to significantly inhibit phonon-related mechanisms for energy losses, an effect referred to as a phonon bottleneck. It has been suggested recently that the phonon bottleneck in 3D-confined systems can be removed due to enhanced role of Auger-type interactions. In this paper we report femtosecond (fs) studies of ultrafast optical nonlinearities, and energy relaxation and trap ping dynamics in three types of quantum-dot systems: semiconductor NC/glass composites made by high temperature precipitation, ion-implanted NC's, and colloidal NC'S. Comparison of ultrafast data for different samples allows us to separate effects being intrinsic to quantum dots from those related to lattice imperfections and interface properties.

  3. Investigation of redox processes at semiconductor electrode liquid junctions

    SciTech Connect (OSTI)

    Koval, C.A.

    1990-08-01T23:59:59.000Z

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

  4. Materials Synthesis from Atoms to Systems | ORNL

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

    Porous Materials Thin Film Deposition Single Crystal Growth Texture Control Additive Manufacturing Nanomaterials Synthesis Designer Organic Molecules Related Research Materials...

  5. Los Alamos Lab: Materials Physics & Applications Division

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

    ADEPS Materials Physics and Applications, MPA About Us Organization Jobs Materials Physics & Applications Home Center for Integrated Nanotechnologies Superconductivity Technology...

  6. Semiconductor switch geometry with electric field shaping

    DOE Patents [OSTI]

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

    1994-01-01T23:59:59.000Z

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

  7. Semiconductor switch geometry with electric field shaping

    DOE Patents [OSTI]

    Booth, R.; Pocha, M.D.

    1994-08-23T23:59:59.000Z

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

  8. Recent progress in degradation and stabilization of organic solar cells

    SciTech Connect (OSTI)

    Cao, Huanqi; He, Weidong; Mao, Yiwu; Lin, Xiao; Ishikawa, Ken; Dickerson, James H.; Hess, Wayne P.

    2014-10-15T23:59:59.000Z

    Stability is of paramount importance in organic semiconductor devices, especially in organic solar cells (OSCs). Serious degradation in air limits wide applications of these flexible, light-weight and low-cost power-generation devices. Studying the stability of organic solar cells will help us understand degradation mechanisms and further improve the stability of these devices. There are many investigations into the efficiency and stability of OSCs. The efficiency and stability of devices even of the same photoactive materials are scattered in different papers. In particular, the extrinsic degradation that mainly occurs near the interface between the organic layer and the cathode is a major stability concern. In the past few years, researchers have developed many new cathodes and cathode buffer layers, some of which have astonishingly improved the stability of OSCs. In this review article, we discuss the recent developments of these materials and summarize recent progresses in the study of the degradation/stability of OSCs, with emphasis on the extrinsic degradation/stability that is related to the intrusion of oxygen and water. The review provides detailed insight into the current status of research on the stability of OSCs and seeks to facilitate the development of highly-efficient OSCs with enhanced stability.

  9. Organic Superconductors

    SciTech Connect (OSTI)

    Charles Mielke

    2009-02-27T23:59:59.000Z

    Intense magnetic fields are an essential tool for understanding layered superconductors. Fundamental electronic properties of organic superconductors are revealed in intense (60 tesla) magnetic fields. Properties such as the topology of the Fermi surface and the nature of the superconducting order parameter are revealed. With modest maximum critical temperatures~13K the charge transfer salt organic superconductors prove to be incredibly valuable materials as their electronically clean nature and layered (highly anisotropic) structures yield insights to the high temperature superconductors. Observation of de Haas-van Alphen and Shubnikov-de Haas quantum oscillatory phenomena, magnetic field induced superconductivity and re-entrant superconductivity are some of the physical phenomena observed in the charge transfer organic superconductors. In this talk, I will discuss the nature of organic superconductors and give an overview of the generation of intense magnetic fields; from the 60 tesla millisecond duration to the extreme 1000 tesla microsecond pulsed magnetic fields.

  10. Glass-Like Heat Conduction in Crystalline Semiconductors

    SciTech Connect (OSTI)

    Nolas, G.S.; Cohn, J.L.; Chakoumakos, B.C.; Slack, G.A.

    1999-06-13T23:59:59.000Z

    The thermal conductivity and structural properties of polycrystalline and single crystal semiconductor type-1 germanium clathrates are reported. Germanium clathrates exhibit thermal conductivities that are typical of amorphous materials. This behavior occurs in spite of their well-defined crystalline structure. The authors employ temperature dependent neutron diffraction data in investigating the displacements of the caged strontium atoms in Sr{sub 8}Ga{sub 16}Ge{sub 30} and their interaction with the polyhedral cages that entrap them. Their aim is to investigate the correlation between the structural properties and the low, glass-like thermal conductivity observed in this compound.

  11. Phase Transitions, Curve Evolution, and the Control of Semiconductor Manufacturing Processes

    E-Print Network [OSTI]

    Given a material that may exist in either of two phases, how will the boundaries between the phases of the region of phase change vanishes. The motion of the sharp interface may be studied through the limitingPhase Transitions, Curve Evolution, and the Control of Semiconductor Manufacturing Processes Jordan

  12. MOVPE growth of semipolar III-nitride semiconductors on CVD graphene Priti Gupta n

    E-Print Network [OSTI]

    Deshmukh, Mandar M.

    MOVPE growth of semipolar III-nitride semiconductors on CVD graphene Priti Gupta n , A.A. Rahman pressure metalorganic vapor phase epitaxy B1. Graphene B1. Nitrides B2. Semiconducting III­V materials a b on graphene grown by chemical vapour deposition. GaN, AlGaN alloys, and InN layers are grown using an Al

  13. FY08 Annual Report: Amorphous Semiconductors for Gamma Radiation Detection (ASGRAD)

    SciTech Connect (OSTI)

    Johnson, Bradley R.; Riley, Brian J.; Crum, Jarrod V.; Ryan, Joseph V.; Sundaram, S. K.; McCloy, John S.; Rockett, Angus

    2009-02-01T23:59:59.000Z

    This is the annual report for an old project funded by NA22. The purpose of the project was to develop amorphous semiconductors for use as radiation detectors. The annual report contains information about the progress made in synthesizing, characterizing, and radiation response testing of these new materials.

  14. Field emission cooling of thermoelectric semiconductor PbTe M. S. Chung,1,a

    E-Print Network [OSTI]

    Mayer, Alexandre

    Field emission cooling of thermoelectric semiconductor PbTe M. S. Chung,1,a A. Mayer,2 B. L. Weiss due to field emission from n-type PbTe, a typical thermoelectric material. We show that, by calculating the average energies of field and replacement electrons, the energy exchange in field emission

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

    E-Print Network [OSTI]

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

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

    E-Print Network [OSTI]

    Bowers, John

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

  17. EMC/FDTD/MD FOR MULTIPHYSICS CHARACTERIZATION OF SEMICONDUCTORS AT THZ FREQUENCIES

    E-Print Network [OSTI]

    Knezevic, Irena

    EMC/FDTD/MD FOR MULTIPHYSICS CHARACTERIZATION OF SEMICONDUCTORS AT THZ FREQUENCIES by Keely Willis.1 Ensemble Monte Carlo (EMC) . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 2.2 Finite difference) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3 EMC/FDTD for 2D analysis of materials with low carrier density . . . . . . . . . 22 3.1 EMC

  18. Not Your Grandma's Quilt Researchers develop technique to keep cool high-power semiconductor

    E-Print Network [OSTI]

    devices used in wireless applications, traffic lights and electric cars By Sean Nealon On MAY 8, 2012 in everything from traffic lights to electric cars. Gallium Nitride (GaN), a semiconductor material found by the Nano-Device Laboratory research group led byAlexander Balandin, professor of electrical engineering

  19. Organic Semiconductor Chemistry | MIT-Harvard Center for Excitonics

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)IntegratedSpeeding access toTest andOptimize carbon dioxideCONTRACT AWARDSemiconductor

  20. Exploring Electron Transfer in Organic Semiconductors | MIT-Harvard Center

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) Environmental Assessments (EA) /EmailMolecular Solids1 BeamlineExplorefor

  1. Transport Equations for Semiconductors Prof. Dr. Ansgar Jungel

    E-Print Network [OSTI]

    Jüngel, Ansgar

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

  2. Kinetic and Macroscopic Models for Semiconductors Ansgar Jungel

    E-Print Network [OSTI]

    Jüngel, Ansgar

    Kinetic and Macroscopic Models for Semiconductors Ansgar J¨ungel Vienna University of Technology, Austria www.jungel.at.vu Ansgar J¨ungel (TU Wien) Kinetic Semiconductor Models www.jungel.at.vu 1 / 165 #12;Contents 1 Introduction 2 Semiconductor modeling Basics of semiconductor physics Kinetic models 3

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

    E-Print Network [OSTI]

    Fang, Yuguang "Michael"

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

  4. Field of Expertise Materials Science

    E-Print Network [OSTI]

    in materials research co-operates intensively with many globally active companies, such as Infineon, Austria and hybrid solar cells Ceramic semiconductors, sensors and piezoelectric components Lithium-ion batteries New welding methods RESEARCH OPPORTUNITIES FOR COMPANIES AND SCIENTIFIC PARTNERS © TU Graz© TU Graz

  5. Heating device for semiconductor wafers

    DOE Patents [OSTI]

    Vosen, S.R.

    1999-07-27T23:59:59.000Z

    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.

  6. Heating device for semiconductor wafers

    DOE Patents [OSTI]

    Vosen, Steven R. (Berkeley, CA)

    1999-01-01T23:59:59.000Z

    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.

  7. Diluted magnetic semiconductor nanowires exhibiting magnetoresistance

    DOE Patents [OSTI]

    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

    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.

  8. Materials at UC Santa Barbara Ranked in the top two programs in the country for research impact and citations, materials research at UC

    E-Print Network [OSTI]

    Akhmedov, Azer

    as semiconductors · Soft cellular materials · Nanostructured materials by molecular beam epitaxy Solid chemistry to synthesize conjugated polymer composites for use in photovoltaic and optoelectronic devices in energy efficiency in Buildings, Lighting, Computing, Electronics & Photonics, Energy Production & Storage

  9. Scanning probe characterization of novel semiconductor materials and devices

    E-Print Network [OSTI]

    Zhou, Xiaotian

    2007-01-01T23:59:59.000Z

    InGaN/GaN quantum wells by scanning capacitance microscopywell heterostructures by scanning capacitance microscopy”InGaN/GaN quantum wells by scanning capacitance microscopy”

  10. Photocell utilizing a wide-bandgap semiconductor material

    DOE Patents [OSTI]

    Carlson, David E. (Yardley, PA); Williams, Brown F. (Princeton, NJ)

    1984-06-05T23:59:59.000Z

    A photocell comprises a p-i-n amorphous silicon structure having a wide bandgap layer adjacent to either the p-type or n-type layer. This structure reduces the absorption of light entering the photocell and the back-diffusion of minority carriers.

  11. Zhongsheng Semiconductor Silicon Material Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty Edit withTianlinPapersWindey Wind Generating

  12. EMei Semiconductor Materials Plant Research Institute | Open Energy

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual SiteofEvaluating A Potential MicrohydroDistrict ofDongjinDynetek42 EIAELO

  13. GRINM Semiconductor Materials Co Ltd Gritek | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual SiteofEvaluating A PotentialJumpGermanFifeGEXA Corp. (New Jersey) JumpGREET Fleet Jump

  14. Semiconductor and Materials Company Inc SAMCO | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro Industries Pvt Ltd JumpInformationScotts Corners,EnergyInformation1987)Semafo

  15. Semiconductor Equipment and Materials International SEMI | Open Energy

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-f < RAPID‎ |Rippey JumpAir JumpCalifornia |

  16. Jiangxi Jingde Semiconductor Materials Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual SiteofEvaluatingGroup | OpenHunanInformationJamesManufacturing | OpenJiangxi Jingde

  17. Electrical Usage Characterization of Semiconductor Processing Tools

    E-Print Network [OSTI]

    Hinson, S. R.

    This paper presents the basic concepts in performing an energy and power audit of a semiconductor process tool. A protocol exists that fully describes these measurements and their use and applicability and it will be described. This protocol...

  18. 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...

  19. NANOSTRUCTURES, MAGNETIC SEMICONDUCTORS AND SPINELECTRONICS Paata Kervalishvili

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    to data storage, switching, lighting and other devices, can lead to substantially new hardwareNANOSTRUCTURES, MAGNETIC SEMICONDUCTORS AND SPINELECTRONICS Paata Kervalishvili Georgian Technical and manipulation on a nanometre scale, which allows the fabrication of nanostructures with the properties mainly

  20. Narrow band gap amorphous silicon semiconductors

    DOE Patents [OSTI]

    Madan, A.; Mahan, A.H.

    1985-01-10T23:59:59.000Z

    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.

  1. Surface phonons of III-V semiconductors

    E-Print Network [OSTI]

    Das, Pradip Kumar

    1994-01-01T23:59:59.000Z

    are the simplest of all semiconductor surfaces. Their atomic relaxations and electronic surface states are rather well understood. There have, however, been surprisingly few experimental studies of their vibrational properties, and ours in the first detailed...

  2. Semiconductor-nanocrystal/conjugated polymer thin films

    DOE Patents [OSTI]

    Alivisatos, A. Paul (Oakland, CA); Dittmer, Janke J. (Munich, DE); Huynh, Wendy U. (Munich, DE); Milliron, Delia (Berkeley, CA)

    2010-08-17T23:59:59.000Z

    The invention described herein provides for thin films and methods of making comprising inorganic semiconductor-nanocrystals dispersed in semiconducting-polymers in high loading amounts. The invention also describes photovoltaic devices incorporating the thin films.

  3. EXCITONIC EIGENSTATES OF DISORDERED SEMICONDUCTOR QUANTUM WIRES

    E-Print Network [OSTI]

    of semiconductors are exploited in solar cells, light emitting diodes, and lasers, and, furthermore, future UNIVERSITY OF MINNESOTA 400 Lind Hall 207 Church Street S.E. Minneapolis, Minnesota 55455­0436 Phone: 612

  4. Science and applications of infrared semiconductor nanocrystals

    E-Print Network [OSTI]

    Geyer, Scott Mitchell

    2010-01-01T23:59:59.000Z

    In this work we study several applications of semiconductor nanocrystals (NCs) with infrared band gaps. In the first half, we explore the physics of two systems with applications in NC based photovoltaics. The physics of ...

  5. Nanopatterned Electrically Conductive Films of Semiconductor Nanocrystals

    E-Print Network [OSTI]

    Mentzel, Tamar

    We present the first semiconductor nanocrystal films of nanoscale dimensions that are electrically conductive and crack-free. These films make it possible to study the electrical properties intrinsic to the nanocrystals ...

  6. Thermovoltaic semiconductor device including a plasma filter

    DOE Patents [OSTI]

    Baldasaro, Paul F. (Clifton Park, NY)

    1999-01-01T23:59:59.000Z

    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.

  7. Flow-Solution-Liquid-Solid Growth of Semiconductor Nanowires: A Novel Approach for Controlled Synthesis

    SciTech Connect (OSTI)

    Hollingsworth, Jennifer A. [Los Alamos National Laboratory; Palaniappan, Kumaranand [Los Alamos National Laboratory; Laocharoensuk, Rawiwan [National Science and Technology Center, Thailand; Smith, Nickolaus A. [Los Alamos National Laboratory; Dickerson, Robert M. [Los Alamos National Laboratory; Casson, Joanna L. [Los Alamos National Laboratory; Baldwin, Jon K. [Los Alamos National Laboratory

    2012-06-07T23:59:59.000Z

    Semiconductor nanowires (SC-NWs) have potential applications in diverse technologies from nanoelectronics and photonics to energy harvesting and storage due to their quantum-confined opto-electronic properties coupled with their highly anisotropic shape. Here, we explore new approaches to an important solution-based growth method known as solution-liquid-solid (SLS) growth. In SLS, molecular precursors are reacted in the presence of low-melting metal nanoparticles that serve as molten fluxes to catalyze the growth of the SC-NWs. The mechanism of growth is assumed to be similar to that of vapor-liquid-solid (VLS) growth, with the clear distinctions of being conducted in solution in the presence of coordinating ligands and at relatively lower temperatures (<300 C). The resultant SC-NWs are soluble in common organic solvents and solution processable, offering advantages such as simplified processing, scale-up, ultra-small diameters for quantum-confinement effects, and flexible choice of materials from group III-V to groups II-VI, IV-VI, as well as truly ternary I-III-VI semiconductors as we recently demonstrates. Despite these advantages of SLS growth, VLS offers several clear opportunities not allowed by conventional SLS. Namely, VLS allows sequential addition of precursors for facile synthesis of complex axial heterostructures. In addition, growth proceeds relatively slowly compared to SLS, allowing clear assessments of growth kinetics. In order to retain the materials and processing flexibility afforded by SLS, but add the elements of controlled growth afforded by VLS, we transformed SLS into a flow based method by adapting it to synthesis in a microfluidic system. By this new method - so-called 'flow-SLS' (FSLS) - we have now demonstrated unprecedented fabrication of multi-segmented SC-NWs, e.g., 8-segmented CdSe/ZnSe defined by either compositionally abrupt or alloyed interfaces as a function of growth conditions. In addition, we have studied growth rates as a function of catalyst size/SC-NW diameter and shown for the first time that SLS is governed by Gibbs-Thomson effects. Lastly, from an applications standpoint, we report growth of SC-NWs from a range of substrates, including ITO-coated glass for fabrication of hybrid photovoltaic devices, comparing these to their quasi zero-dimensional quantum-dot counterparts.

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

    SciTech Connect (OSTI)

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

    2009-07-15T23:59:59.000Z

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

  9. Predicted band structures of III-V semiconductors in wurtzite phase

    E-Print Network [OSTI]

    Amrit De; Craig E. Pryor

    2009-08-13T23:59:59.000Z

    While non-nitride III-V semiconductors typically have a zincblende 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 {\\it 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 lead to new functionalities for designing devices that manipulate spin degrees of freedom.

  10. Fabrication of Semiconductors by Wet Chemical Etch

    E-Print Network [OSTI]

    Francoviglia, Laura

    2008-07-01T23:59:59.000Z

    - ern devices. Beginning with Bardeen, Brittain and Shockley’s invention of the transistor in Bell Labs in 1947 and Kilby and Noyce’s introduction of the integrated circuit about a decade later, semiconductor devices have dramat- ically advanced... ad- dition of impurities, their conductivity can be altered. With the need to manu- facture devices at the micro- and nano- scale, the semiconductor industry has followed “Moore’s Law,” the trend that the number of transistors placed...

  11. A Semiconductor Microlaser for Intracavity Flow Cytometry

    SciTech Connect (OSTI)

    Akhil, O.; Copeland, G.C.; Dunne, J.L.; Gourley, P.L.; Hendricks, J.K.; McDonald, A.E.

    1999-01-20T23:59:59.000Z

    Semiconductor microlasers are attractive components for micro-analysis systems because of their ability to emit coherent intense light from a small aperture. By using a surface-emitting semiconductor geometry, we were able to incorporate fluid flow inside a laser microcavity for the first time. This confers significant advantages for high throughput screening of cells, particulates and fluid analytes in a sensitive microdevice. In this paper we discuss the intracavity microfluidics and present preliminary results with flowing blood and brain cells.

  12. Optical devices featuring nonpolar textured semiconductor layers

    DOE Patents [OSTI]

    Moustakas, Theodore D; Moldawer, Adam; Bhattacharyya, Anirban; Abell, Joshua

    2013-11-26T23:59:59.000Z

    A semiconductor emitter, or precursor therefor, has a substrate and one or more textured semiconductor layers deposited onto the substrate in a nonpolar orientation. The textured layers enhance light extraction, and the use of nonpolar orientation greatly enhances internal quantum efficiency compared to conventional devices. Both the internal and external quantum efficiencies of emitters of the invention can be 70-80% or higher. The invention provides highly efficient light emitting diodes suitable for solid state lighting.

  13. Tuning the oxide/organic interface: Benzene on SnO2,,101... Matthias Batzill,a)

    E-Print Network [OSTI]

    Diebold, Ulrike

    Tuning the oxide/organic interface: Benzene on SnO2,,101... Matthias Batzill,a) Khabibulakh Katsiev,16 As a model molecule for simulating an organic semiconductor film benzene was chosen as a simple -conjugated

  14. Ultrafast Control of Magnetism in Ferromagnetic Semiconductors via Photoexcited Transient Carriers

    E-Print Network [OSTI]

    Cotoros, Ingrid A.

    2009-01-01T23:59:59.000Z

    1.2 Overview of semiconductor2.2 Dilute magnetic semiconductors . . . . . . . . .generated holes in (In,Mn)As Magnetic semiconductor FET

  15. Sub-surface characterization and three dimensional profiling of semiconductors by magnetic resonance force microscopy

    SciTech Connect (OSTI)

    Hammel, P.C.; Moore, G.; Roukes, M.; Zhenyong Zhang

    1996-10-01T23:59:59.000Z

    This is the final report of a two-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project successfully developed a magnetic resonance force microscope (MRFM) instrument to mechanically detect magnetic resonance signals. This technique provides an intrinsically subsurface, chemical-species-specific probe of structure, constituent density and other properties of materials. As in conventional magnetic resonance imaging (MRI), an applied magnetic field gradient selects a well defined volume of the sample for study. However mechanical detection allows much greater sensitivity, and this in turn allows the reduction of the size of the minimum resolvable volume. This requires building an instrument designed to achieve nanometer-scale resolution at buried semiconductor interfaces. High-resolution, three-dimensional depth profiling of semiconductors is critical in the development and fabrication of semiconductor devices. Currently, there is no capability for direct, high-resolution observation and characterization of dopant density, and other critical features of semiconductors. The successful development of MRFM in conjunction with modifications to improve resolution will enable for the first time detailed structural and electronic studies in doped semiconductors and multilayered nanoelectronic devices, greatly accelerating the current pace of research and development.

  16. SYNFORMPeople, Trends and Views in Synthetic Organic Chemistry Direct Conversion of Arylamines

    E-Print Network [OSTI]

    Wang, Jianbo

    the organic molecules which are essential components of drugs, materials, agrochemicals, and all the organic

  17. Ultra-narrow ferromagnetic resonance in organic-based thin films grown via low temperature chemical vapor deposition

    SciTech Connect (OSTI)

    Yu, H.; Harberts, M.; Adur, R.; Hammel, P. Chris; Johnston-Halperin, E., E-mail: ejh@physics.osu.edu, E-mail: epstein@physics.osu.edu [Department of Physics, The Ohio State University, Columbus, Ohio 43210-1117 (United States); Lu, Y. [Department of Chemistry, The Ohio State University, Columbus, Ohio 43210-1173 (United States); Epstein, A. J., E-mail: ejh@physics.osu.edu, E-mail: epstein@physics.osu.edu [Department of Physics, The Ohio State University, Columbus, Ohio 43210-1117 (United States); Department of Chemistry, The Ohio State University, Columbus, Ohio 43210-1173 (United States)

    2014-07-07T23:59:59.000Z

    We present the growth of thin films of the organic-based ferrimagnetic semiconductor V[TCNE]{sub x} (x???2, TCNE: tetracyanoethylene) via chemical vapor deposition. Under optimized growth conditions, we observe a significant increase in magnetic homogeneity, as evidenced by a Curie temperature above 600?K and sharp magnetization switching. Further, ferromagnetic resonance studies reveal a single resonance with full width at half maximum linewidth of 1.4?G, comparable to the narrowest lines measured in inorganic magnetic materials and in contrast to previous studies that showed multiple resonance features. These characteristics are promising for the development of high frequency electronic devices that take advantage of the unique properties of this organic-based material, such as the potential for low cost synthesis combined with low temperature and conformal deposition on a wide variety of substrates.

  18. Spin Transport in Semiconductor heterostructures

    SciTech Connect (OSTI)

    Domnita Catalina Marinescu

    2011-02-22T23:59:59.000Z

    The focus of the research performed under this grant has been the investigation of spin transport in magnetic semiconductor heterostructures. The interest in these systems is motivated both by their intriguing physical properties, as the physical embodiment of a spin-polarized Fermi liquid, as well as by their potential applications as spintronics devices. In our work we have analyzed several different problems that affect the spin dynamics in single and bi-layer spin-polarized two-dimensional (2D) systems. The topics of interests ranged from the fundamental aspects of the electron-electron interactions, to collective spin and charge density excitations and spin transport in the presence of the spin-orbit coupling. The common denominator of these subjects is the impact at the macroscopic scale of the spin-dependent electron-electron interaction, which plays a much more subtle role than in unpolarized electron systems. Our calculations of several measurable parameters, such as the excitation frequencies of magneto-plasma modes, the spin mass, and the spin transresistivity, propose realistic theoretical estimates of the opposite-spin many-body effects, in particular opposite-spin correlations, that can be directly connected with experimental measurements.

  19. Dissipative chaos in semiconductor superlattices

    SciTech Connect (OSTI)

    Alekseev, K.N.; Berman, G.P. [Center for Nonlinear Studies and Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Center for Nonlinear Studies and Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); [Kirensky Institute of Physics, 660036, Krasnoyarsk (Russia); [Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801-3080 (United States); Campbell, D.K.; Cannon, E.H.; Cargo, M.C. [Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801-3080 (United States)] [Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801-3080 (United States)

    1996-10-01T23:59:59.000Z

    We consider the motion of ballistic electrons in a miniband of a semiconductor superlattice (SSL) under the influence of an external, time-periodic electric field. We use a semiclassical, balance-equation approach, which incorporates elastic and inelastic scattering (as dissipation) and the self-consistent field generated by the electron motion. The coupling of electrons in the miniband to the self-consistent field produces a cooperative nonlinear oscillatory mode which, when interacting with the oscillatory external field and the intrinsic Bloch-type oscillatory mode, can lead to complicated dynamics, including dissipative chaos. For a range of values of the dissipation parameters we determine the regions in the amplitude-frequency plane of the external field in which chaos can occur. Our results suggest that for terahertz external fields of the amplitudes achieved by present-day free-electron lasers, chaos may be observable in SSL{close_quote}s. We clarify the nature of this interesting nonlinear dynamics in the superlattice{endash}external-field system by exploring analogies to the Dicke model of an ensemble of two-level atoms coupled with a resonant cavity field, and to Josephson junctions. {copyright} {ital 1996 The American Physical Society.}

  20. Methods for manufacturing monocrystalline or near-monocrystalline cast materials

    DOE Patents [OSTI]

    Stoddard, Nathan G

    2014-04-29T23:59:59.000Z

    Methods are provided for casting one or more of a semiconductor, an oxide, and an intermetallic material. With such methods, a cast body of a monocrystalline form of the one or more of a semiconductor, an oxide, and an intermetallic material may be formed that is free of, or substantially free of, radially-distributed impurities and defects and having at least two dimensions that are each at least about 35 cm.