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1

Implications of mercury interactions with band-gap semiconductor oxides  

SciTech Connect

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.

Granite, E.J.; King, W.P.; Stanko, D.C.; Pennline, H.W.

2008-09-01T23:59:59.000Z

2

Characterization of Novel Semiconductor Alloys for Band Gap Engineering  

E-Print Network (OSTI)

parameter for the lower-energy matrix like band. The fullthe optical matrix is constant with energy and given by: 2 menergy of the host semiconductor. Diagalization of the matrix

Broesler, Robert Joseph

2010-01-01T23:59:59.000Z

3

P and n-type microcrystalline semiconductor alloy material including band gap widening elements, devices utilizing same  

DOE Patents (OSTI)

An n-type microcrystalline semiconductor alloy material including a band gap widening element; a method of fabricating p-type microcrystalline semiconductor alloy material including a band gap widening element; and electronic and photovoltaic devices incorporating said n-type and p-type materials.

Guha, Subhendu (Troy, MI); Ovshinsky, Stanford R. (Bloomfield Hills, MI)

1988-10-04T23:59:59.000Z

4

Band-gap measurements of direct and indirect semiconductors using monochromated electrons  

Science Conference Proceedings (OSTI)

With the development of monochromators for transmission electron microscopes, valence electron-energy-loss spectroscopy (VEELS) has become a powerful technique to study the band structure of materials with high spatial resolution. However, artifacts such as Cerenkov radiation pose a limit for interpretation of the low-loss spectra. In order to reveal the exact band-gap onset using the VEELS method, semiconductors with direct and indirect band-gap transitions have to be treated differently. For direct semiconductors, spectra acquired at thin regions can efficiently minimize the Cerenkov effects. Examples of hexagonal GaN (h-GaN) spectra acquired at different thickness showed that a correct band-gap onset value can be obtained for sample thicknesses up to 0.5 t/{lambda}. In addition, {omega}-q maps acquired at different specimen thicknesses confirm the thickness dependency of Cerenkov losses. For indirect semiconductors, the correct band-gap onset can be obtained in the dark-field mode when the required momentum transfer for indirect transition is satisfied. Dark-field VEEL spectroscopy using a star-shaped entrance aperture provides a way of removing Cerenkov effects in diffraction mode. Examples of Si spectra acquired by displacing the objective aperture revealed the exact indirect transition gap E{sub g} of 1.1 eV.

Gu Lin; Srot, Vesna; Sigle, Wilfried; Koch, Christoph; Aken, Peter van; Ruehle, Manfred [Max-Planck Institute for Metals Research, Heisenbergstrasse 3, D-70569 Stuttgart (Germany); Scholz, Ferdinand; Thapa, Sarad B.; Kirchner, Christoph [Institute of Optoelectronics, University of Ulm, Albert-Einstein-Allee 45, D-89069 Ulm (Germany); Jetter, Michael [Institut fuer Strahlenphysik, University of Stuttgart, D-70569 Stuttgart (Germany)

2007-05-15T23:59:59.000Z

5

Catalyzed Water Oxidation by Solar Irradiation of Band-Gap-Narrowed Semiconductors (Part 2. Overview).  

DOE Green Energy (OSTI)

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

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

2008-03-18T23:59:59.000Z

6

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

DOE Green Energy (OSTI)

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

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

2008-03-18T23:59:59.000Z

7

Time-Resolved Femtosecond Laser Desorption from Wide-BandGap Single Crystals  

Science Conference Proceedings (OSTI)

We have used femtosecond laser pulse pairs to measure the positive ion yield, from wide band-gap single crystals, as a function of time-delay between pulses. Two-pulse correlation allows direct observation of solid state and surface dynamics on an ultrafast timescale. The ion yield, from 265 nm irradiated MgO and KBr, depends critically on the time delay between two sub-threshold pulses. For example, the Mg+ desorption yield displays three distinct features; a coherence peak, followed by rise, and decay features. In contract, the yield of K+ from KBr displays only the coherence peak and picosecond decay features. The data suggest, that although the nanosecond ion desorption mechanism is dominated by defect photoabsorption, significant electron-hole pair production may contribute to the desorption mechanism following femtosecond excitation. Nanosecond photoexcitation of KBr near 6.4 eV leads to desorption of hyperthermal neutral bromine atoms without a significant thermal velocity component. Two-photon femtosecond excitation at 3.2 eV produces very similar results. Multiphoton femtosecond excitation provides an efficient excitation mechanism of the wide-gap material. These results are likely general for ionic crystals and are consistent with a recently described theoretical model.

Hess, Wayne P. (BATTELLE (PACIFIC NW LAB)); Joly, Alan G. (BATTELLE (PACIFIC NW LAB)); Beck, Kenneth M. (University of Central Florida ); Dickinson, J T. (8392); Claude R. Phipps

2002-09-01T23:59:59.000Z

8

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

DOE Green Energy (OSTI)

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

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

2009-06-07T23:59:59.000Z

9

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

SciTech Connect

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

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

2012-06-11T23:59:59.000Z

10

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

DOE Green Energy (OSTI)

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

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

1995-11-01T23:59:59.000Z

11

Substrate-Induced Band-Gap Opening in Epitaxial Graphene  

NLE Websites -- All DOE Office Websites (Extended Search)

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

12

Fabrication of Photonic band gap Materials  

DOE Patents (OSTI)

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

Constant, Kristen; Subramania, Ganapathi S.; Biswas, Rana; Ho, Kai-Ming

2000-01-05T23:59:59.000Z

13

Fabrication of photonic band gap materials  

DOE Patents (OSTI)

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

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

2002-01-15T23:59:59.000Z

14

Wide-Bandgap Semiconductors  

SciTech Connect

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

Chinthavali, M.S.

2005-11-22T23:59:59.000Z

15

Substrate-Induced Band-Gap Opening in Epitaxial Graphene  

NLE Websites -- All DOE Office Websites (Extended Search)

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

16

Substrate-Induced Band-Gap Opening in Epitaxial Graphene  

NLE Websites -- All DOE Office Websites (Extended Search)

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

17

Plasma-Assisted Co-evaporation of S and Se for Wide Band Gap Chalcopyrite Photovoltaics: Final Subcontract Report, December 2001 -- April 2005  

DOE Green Energy (OSTI)

In this work, ITN Energy Systems (ITN) and lower-tier subcontractor Colorado School of Mines (CSM) explore the replacement of the molecular chalcogen precursors during deposition (e.g., Se2 or H2Se) with more reactive chalcogen monomers or radicals (e.g., Se). Molecular species are converted to atomic species in a low-pressure inductively coupled plasma (ICP). This program explored the use of plasma-activated chalcogen sources in CIGS co-evaporation to lower CIGS deposition temperature, increase utilization, increase deposition rate, and improve S:Se stoichiometry control. Plasma activation sources were designed and built, then operated and characterized over a wide range of conditions. Optical emission and mass spectrometry data show that chalcogens are effectively dissociated in the plasma. The enhanced reactivity achieved by the plasma processing was demonstrated by conversion of pre-deposited metal films to respective chalcogen-containing phases at low temperature and low chalcogen flux. The plasma-assisted co-evaporation (PACE) sources were also implemented in CIGS co-evaporation. No benefit from PACE was observed in device results, and frequent deposition failures occurred.

Repins, I.; Wolden, C.

2005-08-01T23:59:59.000Z

18

Single-junction solar cells with the optimum band gap for terrestrial concentrator applications  

DOE Patents (OSTI)

A single-junction solar cell having the ideal band gap for terrestrial concentrator applications. Computer modeling studies of single-junction solar cells have shown that the presence of absorption bands in the direct spectrum has the effect of "pinning" the optimum band gap for a wide range of operating conditions at a value of 1.14.+-.0.02 eV. Efficiencies exceeding 30% may be possible at high concentration ratios for devices with the ideal band gap.

Wanlass, Mark W. (Golden, CO)

1994-01-01T23:59:59.000Z

19

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

SciTech Connect

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

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

2011-05-23T23:59:59.000Z

20

Voltage-Matched, Monolithic, Multi-Band-Gap Devices  

DOE Patents (OSTI)

Monolithic, tandem, photonic cells include at least a first semiconductor layer and a second semiconductor layer, wherein each semiconductor layer includes an n-type region, a p-type region, and a given band-gap energy. Formed within each semiconductor layer is a string of electrically connected photonic sub-cells. By carefully selecting the numbers of photonic sub-cells in the first and second layer photonic sub-cell string(s), and by carefully selecting the manner in which the sub-cells in a first and second layer photonic sub-cell string(s) are electrically connected, each of the first and second layer sub-cell strings may be made to achieve one or more substantially identical electrical characteristics.

Wanlass, M. W.; Mascarenhas, A.

2006-08-22T23:59:59.000Z

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


21

Tuning Band Gap Energies in Pb3(C6X6) Extended Solid-State Structures  

SciTech Connect

A detailed plane-wave density functional theory investigation of the solid-state properties of the extended organometallic system Pb{sub 3}C{sub 6}X{sub 6} for X = O, S, Se, and Te has been performed. Initial geometry parameters for the Pb-X and C-X bond distances were obtained from optimized calculations on molecular fragment models. The Pb{sub 3}C{sub 6}X{sub 6} extended solid molecular structures were constructed in the space group P6/mmm on the basis of the known structure for X = S. Ground-state geometries, band gap energies, densities of states, and charge densities were calculated with the PBE-generalized gradient exchange-correlation functional and the HSE06 hybrid exchange-correlation functional. The PBE band gap energies were found to be lower than the HSE06 values by >0.7 eV. The band energies at points of high symmetry along the first Brillouin zone in the crystal were larger than the overall band gap of the system. Pb{sub 3}C{sub 6}O{sub 6} was predicted to be a direct semiconductor ({Lambda} point) with a PBE band gap of 0.28 eV and an HSE06 band gap of 1.06 eV. Pb{sub 3}C{sub 6}S{sub 6} and Pb{sub 3}C{sub 6}Se{sub 6} were predicted to have indirect band gaps. The PBE band gap for Pb{sub 3}C{sub 6}S{sub 6} was 0.98 eV, and the HSE06 band gap was 1.91 eV. The HSE06 value is in good agreement with the experimentally observed band gap of 1.7 eV. Pb{sub 3}C{sub 6}Se{sub 6} has a PBE band gap of 0.56 eV and a HSE06 band gap of 1.41 eV. Pb{sub 3}C{sub 6}Te{sub 6} was predicted to be metallic with both of the PBE and HSE06 functionals. A detailed analysis of the PBE band structure and partial density of states at two points before and after the metallic behavior reveals a change in orbital character indicative of band crossing in Pb{sub 3}C{sub 6}Te{sub 6}. These results show that the band gap energies can be fine-tuned by changing the substituent X atom.

Stott, Amanda C.; Vaid, Thomas P.; Bylaska, Eric J.; Dixon, David A.

2012-04-19T23:59:59.000Z

22

Single-junction solar cells with the optimum band gap for terrestrial concentrator applications  

DOE Patents (OSTI)

A single-junction solar cell is described having the ideal band gap for terrestrial concentrator applications. Computer modeling studies of single-junction solar cells have shown that the presence of absorption bands in the direct spectrum has the effect of ''pinning'' the optimum band gap for a wide range of operating conditions at a value of 1.14[+-]0.02 eV. Efficiencies exceeding 30% may be possible at high concentration ratios for devices with the ideal band gap. 7 figures.

Wanlass, M.W.

1994-12-27T23:59:59.000Z

23

Substrate-Induced Band-Gap Opening in Epitaxial Graphene  

NLE Websites -- All DOE Office Websites (Extended Search)

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

24

Wide-Bandgap Compound Semiconductors to Enable Novel Semiconductor Devices  

DOE Green Energy (OSTI)

This report represents the completion of a three-year Laboratory-Directed Research and Development (LDRD) program that focused on research and development of GaN-based wide bandgap semiconductor materials (referred to as III-N materials). Our theoretical investigations include the determination of fundamental materials parameters from first-principles calculations, the study of gain properties of III-N heterostructures using a microscopic laser theory and density-functional-theory, charge-state calculations to determine the core structure and energy levels of dislocations in III-N materials. Our experimental investigations include time-resolved photoluminescence and magneto-luminescence studies of GaN epilayers and multiquantum well samples as well as x-ray diffraction studies of AlGaN ternary alloys. In addition, we performed a number of experiments to determine how various materials processing steps affect both the optical and electrical properties of GaN-based materials. These studies include photoluminescence studies of GaN epilayers after post-growth rapid thermal annealing, ion implantation to produce n- and p-type material and electrical and optical studies of plasma-etched structures.

Crawford, M.H.; Chow, W.W.; Wright, A.F.; Lee, S.R.; Jones, E.D.; Han, J.; Shul, R.J.

1999-04-01T23:59:59.000Z

25

Energy Band Gap Engineering of Graphene Nanoribbons  

E-Print Network (OSTI)

We investigate electronic transport in lithographically patterned graphene ribbon structures where the lateral confinement of charge carriers creates an energy gap near the charge neutrality point. Individual graphene layers are contacted with metal electrodes and patterned into ribbons of varying widths and different crystallographic orientations. The temperature dependent conductance measurements show larger energy gaps opening for narrower ribbons. The sizes of these energy gaps are investigated by measuring the conductance in the non-linear response regime at low temperatures. We find that the energy gap scales inversely with the ribbon width, thus demonstrating the ability to engineer the band gap of graphene nanostructures by lithographic processes.

Han, M Y

2007-01-01T23:59:59.000Z

26

Wide Bandgap Semiconductors: Essential to Our Technology Future |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

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

27

DEPENDENCE OF BAND GAP ON DEPOSITION PARAMETERS IN CdSe SINTERED FILMS  

E-Print Network (OSTI)

II-VI semiconductors form an important class of opto-electronic materials. CdSe is a promising material for the fabrication of photovoltaic devices. Polycrystalline CdSe films have been deposited onto ultra clean glass substrates by sintering process. The optical band gap of these films was determined by reflectance measurements in wavelength range 400-850 nm. The band gap of these films was observed to increase with increase in sintering temperature and sintering time separately. The crystal structure and lattice parameter of these films were determined from x-ray diffractograms. The films were polycrystalline in nature having cubic zinc blende structure.

unknown authors

2008-01-01T23:59:59.000Z

28

Wide Bandgap Semiconductors: Pursuing the Promise  

NLE Websites -- All DOE Office Websites (Extended Search)

the size of an automotive cooling system by 60% or even eliminate the secondary liquid cooling system. 2 Military: WBG semiconductors have great potential as an enabling...

29

The Development of Layered Photonic Band Gap Structures Using a Micro-Transfer Molding Technique  

SciTech Connect

Photonic band gap (PBG) crystals are periodic dielectric structures that manipulate electromagnetic radiation in a manner similar to semiconductor devices manipulating electrons. Whereas a semiconductor material exhibits an electronic band gap in which electrons cannot exist, similarly, a photonic crystal containing a photonic band gap does not allow the propagation of specific frequencies of electromagnetic radiation. This phenomenon results from the destructive Bragg diffraction interference that a wave propagating at a specific frequency will experience because of the periodic change in dielectric permitivity. This gives rise to a variety of optical applications for improving the efficiency and effectiveness of opto-electronic devices. These applications are reviewed later. Several methods are currently used to fabricate photonic crystals, which are also discussed in detail. This research involves a layer-by-layer micro-transfer molding ({mu}TM) and stacking method to create three-dimensional FCC structures of epoxy or titania. The structures, once reduced significantly in size can be infiltrated with an organic gain media and stacked on a semiconductor to improve the efficiency of an electronically pumped light-emitting diode. Photonic band gap structures have been proven to effectively create a band gap for certain frequencies of electro-magnetic radiation in the microwave and near-infrared ranges. The objective of this research project was originally two-fold: to fabricate a three dimensional (3-D) structure of a size scaled to prohibit electromagnetic propagation within the visible wavelength range, and then to characterize that structure using laser dye emission spectra. As a master mold has not yet been developed for the micro transfer molding technique in the visible range, the research was limited to scaling down the length scale as much as possible with the current available technology and characterizing these structures with other methods.

Kevin Jerome Sutherland

2001-05-01T23:59:59.000Z

30

Furan Substituted Diketopyrrolopyrrole and Thienylenevinylene Based Low Band Gap Copolymer for High Mobility Organic Thin Film Transistors  

Science Conference Proceedings (OSTI)

A novel solution processable donor-acceptor (D-A) based low band gap polymer semiconductor poly{l_brace}3,6-difuran-2-yl-2,5-di(2-octyldodecyl)-pyrrolo[3,4-c]pyrrole-1,4-dione-alt-thienylenevinylene{r_brace} (PDPPF-TVT), was designed and synthesized by a Pd-catalyzed Stille coupling route. An electron deficient furan based diketopyrrolopyrrole (DPP) block and electron rich thienylenevinylene (TVT) donor moiety were attached alternately in the polymer backbone. The polymer exhibited good solubility, film forming ability and thermal stability. The polymer exhibits wide absorption bands from 400 nm to 950 nm (UV-vis-NIR region) with absorption maximum centered at 782 nm in thin film. The optical band gap (E{sub g}{sup opt}) calculated from the polymer film absorption onset is around 1.37 eV. The {pi}-energy band level (ionization potential) calculated by photoelectron spectroscopy in air (PESA) for PDPPF-TVT is around 5.22 eV. AFM and TEM analyses of the polymer reveal nodular terrace morphology with optimized crystallinity after 200 C thermal annealing. This polymer exhibits p-channel charge transport characteristics when used as the active semiconductor in organic thin-film transistor (OTFT) devices. The highest hole mobility of 0.13 cm{sup 2} V{sup -1} s{sup -1} is achieved in bottom gate and top-contact OTFT devices with on/off ratios in the range of 10{sup 6}-10{sup 7}. This work reveals that the replacement of thiophene by furan in DPP copolymers exhibits such a high mobility, which makes DPP furan a promising block for making a wide range of promising polymer semiconductors for broad applications in organic electronics.

Sonar, Prashant [Institute of Materials Research and Engineering (IMRE), Agency for Science, Technology, and Research; Zhuo, Jing-Mei [Department of Physics, National University of Singapore; Zhao, Li-Hong [National University of Singapore; Lim, Kai-Ming [Department of Physics, National University of Singapore; Chen, Jihua [ORNL; Rondinone, Adam Justin [ORNL; Singh, Samarendra [Institute of Materials Research and Engineering (IMRE), Agency for Science, Technology, and Research; Chua, Lay-Lay [National University of Singapore; Ho, Peter [National University of Singapore; Dodabalapur, Ananth [National University of Singapore

2012-01-01T23:59:59.000Z

31

Method for Creating Photonic Band Gap Materials  

Innovative microstructures that can direct light in a manner similar to the way semiconductors can influence electrons can be produced by creating ...

32

In Situ Band Gap Engineering of Carbon Nanotubes  

VOLUME 79, NUMBER 11 PHYSICAL REVIEW LETTERS 15SEPTEMBER 1997 In Situ Band Gap Engineering of Carbon Nanotubes Vincent H. Crespi* and Marvin L. Cohen

33

Diluted II-VI Oxide Semiconductors with Multiple Band Gaps  

energy spectrum, Zn 1 yMn yO xTe 1 x is a material perfectly satisfying the conditions for single-junction ... conduction states of the matrix are clearly observed in

34

Diluted II-VI Oxide Semiconductors with Multiple Band Gaps  

energy spectrum, Zn 1 yMn yO xTe 1 x is a material perfectly satisfying the conditions for single-junction ... conduction states of the matrix are ...

35

Design of photonic crystals with multiple and combined band gaps  

E-Print Network (OSTI)

We present and use an algorithm based on convex conic optimization to design two-dimensional photonic crystals with large absolute band gaps. Among several illustrations we show that it is possible to design photonic ...

Men, H.

36

Feasibility of band gap engineering of pyrite FeS?  

E-Print Network (OSTI)

We use first-principles computations to investigate whether the band gap of pyrite FeS? can be increased by alloying in order to make it a more effective photovoltaic material. In addition to the isostructural compounds ...

Sun, Ruoshi

37

Fabrication of Ceramic Layer-by-Layer Infrared Wavelength Photonic Band Gap Crystals  

SciTech Connect

Photonic band gap (PBG) crystals, also known as photonic crystals, are periodic dielectric structures which form a photonic band gap that prohibit the propagation of electromagnetic (EM) waves of certain frequencies at any incident angles. Photonic crystals have several potential applications including zero-threshold semiconductor lasers, the inhibition of spontaneous emission, dielectric mirrors, and wavelength filters. If defect states are introduced in the crystals, light can be guided from one location to another or even a sharp bending of light in micron scale can be achieved. This generates the potential for optical waveguide and optical circuits, which will contribute to the improvement in the fiber-optic communications and the development of high-speed computers.

Henry Hao-Chuan Kang

2004-12-19T23:59:59.000Z

38

Method of depositing wide bandgap amorphous semiconductor materials  

DOE Patents (OSTI)

A method of depositing wide bandgap p type amorphous semiconductor materials on a substrate without photosensitization by the decomposition of one or more higher order gaseous silanes in the presence of a p-type catalytic dopant at a temperature of about 200.degree. C. and a pressure in the range from about 1-50 Torr.

Ellis, Jr., Frank B. (Princeton Junction, NJ); Delahoy, Alan E. (Rocky Hill, NJ)

1987-09-29T23:59:59.000Z

39

Numericl modeling of graded band gap CIGS solar cells  

DOE Green Energy (OSTI)

The high efficiency reported recently by NREL for CIGS solar cells demonstrates the potential of band gap grading in producing high efficiency thin film solar cells. In order to reap the full benefits of this design strategy, a clear understanding of the fundamental device physics of these structures is needed. The purpose of this paper is to examine the role grading of the band gap plays in achieving high conversion efficiencies. To aid in this examination, a detailed numerical device simulation program, ADEPT, is used.

Gray, J.L.; Lee, Youn Jung

1994-12-31T23:59:59.000Z

40

Multi-junction, monolithic solar cell using low-band-gap materials lattice matched to GaAs or Ge  

DOE Patents (OSTI)

A multi-junction, monolithic, photovoltaic solar cell device is provided for converting solar radiation to photocurrent and photovoltage with improved efficiency. The solar cell device comprises a plurality of semiconductor cells, i.e., active p/n junctions, connected in tandem and deposited on a substrate fabricated from GaAs or Ge. To increase efficiency, each semiconductor cell is fabricated from a crystalline material with a lattice constant substantially equivalent to the lattice constant of the substrate material. Additionally, the semiconductor cells are selected with appropriate band gaps to efficiently create photovoltage from a larger portion of the solar spectrum. In this regard, one semiconductor cell in each embodiment of the solar cell device has a band gap between that of Ge and GaAs. To achieve desired band gaps and lattice constants, the semiconductor cells may be fabricated from a number of materials including Ge, GaInP, GaAs, GaInAsP, GaInAsN, GaAsGe, BGaInAs, (GaAs)Ge, CuInSSe, CuAsSSe, and GaInAsNP. To further increase efficiency, the thickness of each semiconductor cell is controlled to match the photocurrent generated in each cell. To facilitate photocurrent flow, a plurality of tunnel junctions of low-resistivity material are included between each adjacent semiconductor cell. The conductivity or direction of photocurrent in the solar cell device may be selected by controlling the specific p-type or n-type characteristics for each active junction.

Olson, Jerry M. (Lakewood, CO); Kurtz, Sarah R. (Golden, CO); Friedman, Daniel J. (Lakewood, CO)

2001-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "wide band-gap semiconductor" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
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41

Wide Bandgap Semiconductors for Clean Energy Workshop: Summary...  

NLE Websites -- All DOE Office Websites (Extended Search)

Facilitator: Foundry service is from Defense Advanced Research Projects Agency (DARPA), Metal Oxide Semiconductor Implementation Service (MOSIS). There is an evaluation of...

42

Substrate-induced band gap opening in epitaxial graphene  

Science Conference Proceedings (OSTI)

Graphene has shown great application potential as the hostmaterial for next-generation electronic devices. However, despite itsintriguing properties, one of the biggest hurdles for graphene to beuseful as an electronic material is the lack of an energy gap in itselectronic spectra. This, for example, prevents the use of graphene inmaking transistors. Although several proposals have been made to open agap in graphene's electronic spectra, they all require complexengineering of the graphene layer. Here, we show that when graphene isepitaxially grown on SiC substrate, a gap of ~;0.26 eV is produced. Thisgap decreases as the sample thickness increases and eventually approacheszero when the number of layers exceeds four. We propose that the originof this gap is the breaking of sublattice symmetry owing to thegraphene-substrate interaction. We believe that our results highlight apromising direction for band gap engineering of graphene.

Zhou, S.Y.; Gweon, G.-H.; Fedorov, A.V.; First, P.N.; de Heer,W.A.; Lee, D.-H.; Guinea, F.; Castro Neto, A.H.; Lanzara, A.

2007-09-08T23:59:59.000Z

43

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

Innovative microstructures that can direct light in a manner similar to the way semiconductors can influence electrons can be produced by creating what is termed a ...

44

Single-junction solar cells with the optimum band gap for ...  

A single-junction solar cell having the ideal band gap for terrestrial concentrator applications. Computer modeling studies of single-junction solar cells have shown ...

45

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

DOE Patents (OSTI)

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.

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

2008-03-18T23:59:59.000Z

46

Photocell utilizing a wide-bandgap semiconductor material  

DOE Patents (OSTI)

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.

Carlson, David E. (Yardley, PA); Williams, Brown F. (Princeton, NJ)

1984-06-05T23:59:59.000Z

47

Calculation of wakefields in a 17 GHz beam-driven photonic band-gap accelerator structure  

E-Print Network (OSTI)

We present the theoretical analysis and computer simulation of the wakefields in a 17 GHz photonic band-gap (PBG) structure for accelerator applications. Using the commercial code CST Particle Studio, the fundamental ...

Hu, Min

48

Thermophotovoltaic conversion using selective infrared line emitters and large band gap photovoltaic devices  

DOE Patents (OSTI)

Efficient thermophotovoltaic conversion can be performed using photovoltaic devices with a band gap in the 0.75-1.4 electron volt range, and selective infrared emitters chosen from among the rare earth oxides which are thermally stimulated to emit infrared radiation whose energy very largely corresponds to the aforementioned band gap. It is possible to use thermovoltaic devices operating at relatively high temperatures, up to about 300.degree. C., without seriously impairing the efficiency of energy conversion.

Brandhorst, Jr., Henry W. (Auburn, AL); Chen, Zheng (Auburn, AL)

2000-01-01T23:59:59.000Z

49

Effect of interfacial lattice mismatch on bulk carrier concentration and band gap of InN  

SciTech Connect

The issue of ambiguous values of the band gap (0.6 to 2 eV) of InN thin film in literature has been addressed by a careful experiment. We have grown wurtzite InN films by PA-MBE simultaneously on differently modified c-plane sapphire substrates and characterized by complementary structural and chemical probes. Our studies discount Mie resonances caused by metallic In segregation at grain boundaries as the reason for low band gap values ( Almost-Equal-To 0.6 eV) and also the formation of Indium oxides and oxynitrides as the cause for high band gap value ( Almost-Equal-To 2.0 eV). It is observed that polycrystallinity arising from azimuthal miss-orientation of c-oriented wurtzite InN crystals increases the carrier concentration and the band gap values. We have reviewed the band gap, carrier concentration, and effective mass of InN in literature and our own measurements, which show that the Moss-Burstein relation with a non-parabolic conduction band accounts for the observed variation of band gap with carrier concentration.

Kuyyalil, Jithesh [FOTON, UMR 6082, INSA, F-35708 Rennes (France); Tangi, Malleswararao; Shivaprasad, S. M. [Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore-560064 (India)

2012-10-15T23:59:59.000Z

50

On the Relation between Perfect Tunneling and Band Gaps for SNG Metamaterial Structures  

E-Print Network (OSTI)

In this article we have proposed a compact classification of isotropic and homogenous single negative (SNG) electromagnetic metamaterial based perfect tunneling unit cells. This has been made by means of the band gap theories and properties of the arrays made up of these unit cells. Based on their reported characteristics, we have proposed new structures that simultaneously show perfect tunneling band and complete band gap (CBG - omni directional stop band for both polarizations). Besides, we have identified perfect tunneling which can be considered as "phase shifted perfect tunneling". Several interesting and new phenomena like Complete Perfect Tunneling (CPT - omni-directional perfect tunneling for both polarizations), Band Gap Shifting, CBG in Double Positive (DPS) material range, etc. have been reported with proper physical and mathematical explanations.

Mahdy, M R C; Shawon, Jubayer; Al-Quaderi, Golam Dastegir; Matin, M A

2013-01-01T23:59:59.000Z

51

Method of manufacturing flexible metallic photonic band gap structures, and structures resulting therefrom  

DOE Patents (OSTI)

A method of manufacturing a flexible metallic photonic band gap structure operable in the infrared region, comprises the steps of spinning on a first layer of dielectric on a GaAs substrate, imidizing this first layer of dielectric, forming a first metal pattern on this first layer of dielectric, spinning on and imidizing a second layer of dielectric, and then removing the GaAs substrate. This method results in a flexible metallic photonic band gap structure operable with various filter characteristics in the infrared region. This method may be used to construct multi-layer flexible metallic photonic band gap structures. Metal grid defects and dielectric separation layer thicknesses are adjusted to control filter parameters.

Gupta, Sandhya (Bloomington, MN); Tuttle, Gary L. (Ames, IA); Sigalas, Mihail (Ames, IA); McCalmont, Jonathan S. (Ames, IA); Ho, Kai-Ming (Ames, IA)

2001-08-14T23:59:59.000Z

52

Science and applications of infrared semiconductor nanocrystals  

E-Print Network (OSTI)

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 ...

Geyer, Scott Mitchell

2010-01-01T23:59:59.000Z

53

High power breakdown testing of a photonic band-gap accelerator structure with elliptical rods  

E-Print Network (OSTI)

An improved single-cell photonic band-gap (PBG) structure with an inner row of elliptical rods (PBG-E) was tested with high power at a 60 Hz repetition rate at X-band (11.424 GHz), achieving a gradient of 128??MV/m at a ...

Munroe, Brian James

54

Periodic dielectric structure for production of photonic band gap and method for fabricating the same  

DOE Patents (OSTI)

A method is disclosed for fabricating a periodic dielectric structure which exhibits a photonic band gap. Alignment holes are formed in a wafer of dielectric material having a given crystal orientation. A planar layer of elongate rods is then formed in a section of the wafer. The formation of the rods includes the step of selectively removing the dielectric material of the wafer between the rods. The formation of alignment holes and layers of elongate rods and wafers is then repeated to form a plurality of patterned wafers. A stack of patterned wafers is then formed by rotating each successive wafer with respect to the next-previous wafer, and then placing the successive wafer on the stack. This stacking results in a stack of patterned wafers having a four-layer periodicity exhibiting a photonic band gap. 42 figures.

Ozbay, E.; Tuttle, G.; Michel, E.; Ho, K.M.; Biswas, R.; Chan, C.T.; Soukoulis, C.

1995-04-11T23:59:59.000Z

55

Periodic dielectric structure for production of photonic band gap and method for fabricating the same  

DOE Patents (OSTI)

A method for fabricating a periodic dielectric structure which exhibits a photonic band gap. Alignment holes are formed in a wafer of dielectric material having a given crystal orientation. A planar layer of elongate rods is then formed in a section of the wafer. The formation of the rods includes the step of selectively removing the dielectric material of the wafer between the rods. The formation of alignment holes and layers of elongate rods and wafers is then repeated to form a plurality of patterned wafers. A stack of patterned wafers is then formed by rotating each successive wafer with respect to the next-previous wafer, and then placing the successive wafer on the stack. This stacking results in a stack of patterned wafers having a four-layer periodicity exhibiting a photonic band gap.

Ozbay, Ekmel (Ames, IA); Tuttle, Gary (Ames, IA); Michel, Erick (Ames, IA); Ho, Kai-Ming (Ames, IA); Biswas, Rana (Ames, IA); Chan, Che-Ting (Ames, IA); Soukoulis, Costas (Ames, IA)

1995-01-01T23:59:59.000Z

56

Photonic band gaps in one-dimensional magnetized plasma photonic crystals with arbitrary magnetic declination  

Science Conference Proceedings (OSTI)

In this paper, the properties of photonic band gaps and dispersion relations of one-dimensional magnetized plasma photonic crystals composed of dielectric and magnetized plasma layers with arbitrary magnetic declination are theoretically investigated for TM polarized wave based on transfer matrix method. As TM wave propagates in one-dimensional magnetized plasma photonic crystals, the electromagnetic wave can be divided into two modes due to the influence of Lorentz force. The equations for effective dielectric functions of such two modes are theoretically deduced, and the transfer matrix equation and dispersion relations for TM wave are calculated. The influences of relative dielectric constant, plasma collision frequency, incidence angle, plasma filling factor, the angle between external magnetic field and +z axis, external magnetic field and plasma frequency on transmission, and dispersion relation are investigated, respectively, and some corresponding physical explanations are also given. From the numerical results, it has been shown that plasma collision frequency cannot change the locations of photonic band gaps for both modes, and also does not affect the reflection and transmission magnitudes. The characteristics of photonic band gaps for both modes can be obviously tuned by relative dielectric constant, incidence angle, plasma filling factor, the angle between external magnetic field and +z axis, external magnetic field and plasma frequency, respectively. These results would provide theoretical instructions for designing filters, microcavities, and fibers, etc.

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

2012-12-15T23:59:59.000Z

57

Analysis of plasma-magnetic photonic crystal with a tunable band gap  

SciTech Connect

In this paper, electromagnetic wave propagation through the one-dimensional plasma-magnetic photonic crystal in the presence of external magnetic field has been analyzed. The dispersion relation, transmission and reflection coefficients have been obtained by using the transfer matrix method. It is investigated how photonic band gap of photonic crystals will be tuned when both dielectric function {epsilon} and magnetic permeability {mu} of the constitutive materials, depend on applied magnetic field. This is shown by one dimensional photonic crystals consisting of plasma and ferrite material layers stacked alternately.

Mehdian, H.; Mohammadzahery, Z.; Hasanbeigi, A. [Department of Physics and Plasma Research Institute of Tarbiat Moallem University, 49 Dr Mofatteh Avenue, Tehran 15614 (Iran, Islamic Republic of)

2013-04-15T23:59:59.000Z

58

2010 Defects in Semiconductors GRC  

SciTech Connect

Continuing its tradition of excellence, this Gordon Conference will focus on research at the forefront of the field of defects in semiconductors. The conference will have a strong emphasis on the control of defects during growth and processing, as well as an emphasis on the development of novel defect detection methods and first-principles defect theories. 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 will deal with point and extended defects in a broad range of electronic materials. This approach has proved to be extremely fruitful for advancing fundamental understanding in emerging materials such as wide-band-gap semiconductors, oxides, sp{sup 2} carbon based-materials, and photovoltaic/solar cell materials, and in understanding important defect phenomena such as doping bottleneck in nanostructures and the diffusion of defects and impurities. The program consists of about twenty invited talks and a number of contributed poster sessions. The emphasis should be on work which has yet to be published. The large amount of discussion time provides an ideal forum for dealing with topics that are new and/or controversial.

Shengbai Zhang

2011-01-06T23:59:59.000Z

59

Correlation between surface chemistry, density and band gap in nanocrystalline WO3 thin films  

Science Conference Proceedings (OSTI)

Nanocrystalline WO3 thin films were produced by sputter-deposition by varying the ratio of argon to oxygen in the reactive gas mixture during deposition. The surface chemistry, physical characteristics, and optical properties of nanocrystalline WO3 films were evaluated using X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray reflectivity (XRR), and spectrophotometric measurements. The effect of ultra-microstructure was significant on the optical properties of WO3 films. The XPS analyses indicate the formation of stoichiometric WO3 with tungsten existing in fully oxidized valence state (W6+). However, WO3 films grown at high oxygen concentration (>60%) in the sputtering gas mixture were over stoichiometric with excess oxygen. XRR simulations, which are based on isotropic WO3 film - SiO2 interface - Si substrate model, indicate that the density of WO3 films is sensitive to the oxygen content in the sputtering gas. The spectral transmission of the films increased with the increasing oxygen. The band gap of these films increases from 2.78 eV to 3.25 eV with increasing oxygen. A direct correlation between the film-density and band gap in nanocrystalline WO3 films is established based on the observed results.

Vemuri, Venkata Rama Ses; Engelhard, Mark H.; Ramana, C.V.

2012-03-01T23:59:59.000Z

60

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

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

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

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


61

Pushing the Gradient Limitations of Superconducting Photonic Band Gap Structure Cells  

SciTech Connect

Superconducting photonic band gap resonators present us with unique means to place higher order mode couples in an accelerating cavity and efficiently extract HOMs. An SRF PBG resonator with round rods was successfully tested at LANL demonstrating operation at 15 MV/m. Gradient in the SRF PBG resonator was limited by magnetic quench. To increase the quench threshold in PBG resonators one must design the new geometry with lower surface magnetic fields and preserve the resonator's effectiveness for HOM suppression. The main objective of this research is to push the limits for the high-gradient operation of SRF PBG cavities. A NCRF PBG cavity technology is established. The proof-of-principle operation of SRF PBG cavities is demonstrated. SRF PBG resonators are effective for outcoupling HOMs. PBG technology can significantly reduce the size of SRF accelerators and increase brightness for future FELs.

Simakov, Evgenya I. [Los Alamos National Laboratory; Haynes, William B. [Los Alamos National Laboratory; Kurennoy, Sergey S. [Los Alamos National Laboratory; Shchegolkov, Dmitry [Los Alamos National Laboratory; O'Hara, James F. [Los Alamos National Laboratory; Olivas, Eric R. [Los Alamos National Laboratory

2012-06-07T23:59:59.000Z

62

Ce-doped EuO: Magnetic properties and the indirect band gap  

Science Conference Proceedings (OSTI)

We have prepared and investigated thin films of EuO doped with the rare-earth element cerium. X-ray diffraction, scanning electron microscopy, and energy dispersive x-ray spectroscopy were used to determine the quality of these films prepared by pulsed laser deposition. Ce doping leads to an enhanced Curie temperature near 150 K, close to that seen for oxygen-deficient EuO{sub 1-x}. However, the magnetization of Ce-doped EuO exhibits differences from that observed for Gd-doped and oxygen-deficient samples. The high-resolution angular-resolved photoemission from Ce-doped EuO reveals filling of conduction-band states near the X point. This indicates that the band gap in EuO is indirect, and that at 2% doping Ce-doped EuO{sub 1-x} is at least semimetallic.

Liu Pan; Tang Jinke [Department of Physics and Astronomy, University of Wyoming, Laramie, Wyoming 82071 (United States); Colon Santana, Juan A.; Belashchenko, Kirill D.; Dowben, Peter A. [Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0299 (United States)

2011-04-01T23:59:59.000Z

63

BAs-GaAs Semiconductor Alloys as a Photovoltaic Alternative to Nitride Alloys  

DOE Green Energy (OSTI)

Nitrogen alloyed III-V semiconductor compounds have been intensely studied in recent years due to unusual effects caused by nitrogen alloying. These effects are exploited in band gap engineering for specific applications such as solar cells and blue lasers.

Hart, G. L. W.; Zunger, A.

2000-01-01T23:59:59.000Z

64

Gallium arsenide-based ternary compounds and multi-band-gap solar cell research  

DOE Green Energy (OSTI)

Aim of this contract is the achievement of a high-efficiency, low-cost solar cell. The basic approach to the problem is centered upon the heteroepitaxial growth of a III-V compound material onto a single-crystal silicon wafer. The growth technique employed is metalorganic chemical vapor deposition. The silicon wafer may serve as a mechanical substrate and ohmic contact for a single-junction device, or may contain a p-n junction of its own and form the bottom cell of a two junction tandem solar cell structure. The III-V material for the single-junction case is GaAs and for the two-junction case is either GaAlAs or GaAsP, either material having the proper composition to yield a band gap of approximately 1.7 eV. Results achieved in this contract include the following: (1) a 17.6% efficient GaAs-on-Si solar cell; (2) an 18.5% efficient GaAs-on-Si concentrator solar cell at 400 suns; (3) a 24.8% efficient GaAs-on-GaAs solar cell; (4) a 28.7% efficient GaAs-on-GaAs concentrator solar cell at 200 suns; (5) measurement of the effects of dislocation density and emitter doping on GaAs cells; and (6) improvements in the growth process to achieve reproducible thin AlGaAs window layers with low recombination velocities and environmental stability.

Vernon, S. (Spire Corp., Bedford, MA (United States))

1993-02-01T23:59:59.000Z

65

X-Band Photonic Band-Gap Accelerator Structure Breakdown Experiment  

SciTech Connect

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

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

2012-06-11T23:59:59.000Z

66

Wide band gap solar cells with high stabilized performance. Annual technical report, 15 July 1995--15 July 1996  

DOE Green Energy (OSTI)

This report describes work on an improved understanding of stability in materials and silicon solar cells. Topics include novel intrinsic materials optimization; solar cells optimized for p- and i-layer performance; novel p-type materials; interfaces; and device modeling.

Wronski, C.R.; Collins, R.W.; Fujiwara, H. [Pennsylvania State Univ., University Park, PA (United States)] [and others

1997-01-01T23:59:59.000Z

67

Thermovoltaic semiconductor device including a plasma filter  

DOE Patents (OSTI)

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

Baldasaro, Paul F. (Clifton Park, NY)

1999-01-01T23:59:59.000Z

68

Mixed Semiconductor Nanocrystal Compositions  

NLE Websites -- All DOE Office Websites (Extended Search)

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

69

Optical and electrical properties of III-V nitride wide bandgap semiconductors. Annual report, April 1, 1997--May 31, 1998  

SciTech Connect

The objectives of this project were to investigate the optical and electrical properties of III-nitride wide bandgap semiconductors (GaN, InGaN, AlGaN) and quantum wells, to understand the fundamental optical transitions and impurity properties of these materials, to study the physics components of GaN-based devices, and to provide input for new approaches toward the improvement of materials quality and the optimization of device design. We were the first group to employ transport measurement techniques on the persistent photoconductivity (PPC) state to study the impurity properties of III-nitrides. We were also one of the few research groups m in the world to employ picosecond time-resolved photoluminescence (PL) measurement technique to study mechanisms of optical transitions, LED emission, and lasing m in GaN materials. During this funding period, we have investigated a variety of GaN samples and structures grown by MBE as well as by MOCVD. We have also made a significant progress in MOCVD GaN materials growth. This report briefly discusses the following accomplishments: effects of deep level impurities in the AlGaN/GaN heterostructures; materials characterization of III-nitrides alloys; optical studies of III-nitride epilayers and quantum wells; fabrication and optical studies of III-nitride microdisk arrays; and materials growth by MOCVD.

1998-06-01T23:59:59.000Z

70

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

SciTech Connect

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

Shengbai Zhang and Nancy Ryan Gray

2009-09-16T23:59:59.000Z

71

Band gap tunability of molecular beam epitaxy grown lateral composition modulated GaInP structures by controlling V/III flux ratio  

Science Conference Proceedings (OSTI)

Lateral composition modulated (LCM) GaInP structures were grown on (001) GaAs substrate by molecular beam epitaxy with different V/III flux ratios. Band gap of LCM structures could be tuned from 1.93 eV to 1.83 eV by decreasing flux ratio while maintaining the same photoluminescence intensity, enhanced light absorption, and widened absorption spectrum. It is shown that for band gap tuning of LCM structures, flux ratio adjustment is a more viable method compared to growth temperature adjustment.

Park, K. W. [School of Information and Communications, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of); Park, C. Y. [Micro Systems Laboratory, Samsung Advanced Institute of Technology, Yongin 446-712 (Korea, Republic of); Lee, Y. T. [School of Information and Communications, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of); Department of Nanobio Materials and Electronics, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of); Department of Photonics and Applied Physics, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of)

2012-07-30T23:59:59.000Z

72

A thermovoltaic semiconductor device including a plasma filter  

DOE Patents (OSTI)

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

Baldasaro, Paul F.

1997-12-01T23:59:59.000Z

73

Importance of Solubilizing Group and Backbone Planarity in Low Band Gap Polymers for High Performance Ambipolar field-effect Transistors  

Science Conference Proceedings (OSTI)

We investigated the performance of ambipolar field-effect transistors based on a series of alternating low band gap polymers of oligothiophene and diketopyrrolopyrrole (DPP). The polymers contain oligothiophene units of terthiophene [T3] and thiophene-thienothiophene-thiophene [T2TT] and DPP units carrying branched alkyl chains of 2-hexyldecyl [HD] or 2-octyldodecyl [OD]. The structural variation allows us to do a systematic study on the relationship between the interchain stacking/ordering of semiconducting polymers and their resulting device performance. On the basis of synchrotron X-ray diffraction and atomic force microscopy measurements on polymer films, we found that longer branched alkyl side chains, i.e., OD, and longer and more planar oligothiophene, i.e., T2TT, generate the more crystalline structures. Upon thermal annealing, the crystallinity of the polymers was largely improved, and polymers containing a longer branched alkyl chain responded faster because longer alkyl chains have larger cohesive forces than shorter chains. For all the polymers, excellent ambipolar behavior was observed with a maximum hole and electron mobility of 2.2 and 0.2 cm{sup 2} V{sup -1} s{sup -1}, respectively.

Lee, Joong Suk; Son, Seon Kyoung; Song, Sanghoon; Kim, Hyunjung; Lee, Dong Ryoul; Kim, Kyungkon; Ko, Min Jae; Choi, Dong Hoon; Kim, BongSoo; Cho, Jeong Ho (UST-Korea); (KUS); (Sungkyunkwan); (Soongsil U); (Sogang)

2012-06-13T23:59:59.000Z

74

Hydrogen local vibrational modes in semiconductors  

DOE Green Energy (OSTI)

Following, a review of experimental techniques, theory, and previous work, the results of local vibrational mode (LVM) spectroscopy on hydrogen-related complexes in several different semiconductors are discussed. Hydrogen is introduced either by annealing in a hydrogen ambient. exposure to a hydrogen plasma, or during growth. The hydrogen passivates donors and acceptors in semiconductors, forming neutral complexes. When deuterium is substituted for hydrogen. the frequency of the LVM decreases by approximately the square root of two. By varying the temperature and pressure of the samples, the microscopic structures of hydrogen-related complexes are determined. For group II acceptor-hydrogen complexes in GaAs, InP, and GaP, hydrogen binds to the host anion in a bond-centered orientation, along the [111] direction, adjacent to the acceptor. The temperature dependent shift of the LVMs are proportional to the lattice thermal energy U(T), a consequence of anharmonic coupling between the LVM and acoustical phonons. In the wide band gap semiconductor ZnSe, epilayers grown by metalorganic chemical vapor phase epitaxy (MOCVD) and doped with As form As-H complexes. The hydrogen assumes a bond-centered orientation, adjacent to a host Zn. In AlSb, the DX centers Se and Te are passivated by hydrogen. The second, third, and fourth harmonics of the wag modes are observed. Although the Se-D complex has only one stretch mode, the Se-H stretch mode splits into three peaks. The anomalous splitting is explained by a new interaction between the stretch LVM and multi-phonon modes of the lattice. As the temperature or pressure is varied, and anti-crossing is observed between LVM and phonon modes.

McCluskey, M.D. [Univ. of California, Berkeley, CA (United States). Dept. of Physics]|[Lawrence Berkeley National Lab., CA (United States)

1997-06-01T23:59:59.000Z

75

Strain tuning of topological band order in cubic semiconductors  

SciTech Connect

We theoretically explore the possibility of tuning the topological order of cubic diamond/zinc-blende semi- conductors with external strain. Based on a simple tight-binding model, we analyze the evolution of the cubic semiconductor band structure under hydrostatic or biaxial lattice expansion, by which a generic guiding princi- ple is established that biaxial lattice expansion can induce a topological phase transition of small band-gap cubic semiconductors via a band inversion and symmetry breaking at point. Using density functional theory cal- culations, we demonstrate that a prototype topological trivial semiconductor, InSb, is converted to a nontrivial topological semiconductor with a 2% 3% biaxial lattice expansion.

Feng, wanxiang [Chinese Academy of Sciences; Zhu, Wenguang [University of Tennessee, Knoxville (UTK); Weitering, Hanno [University of Tennessee, Knoxville (UTK); Stocks, George Malcolm [ORNL; Yao, yugui [Chinese Academy of Sciences; Xiao, Di [ORNL

2012-01-01T23:59:59.000Z

76

Hybrid method of making an amorphous silicon P-I-N semiconductor device  

DOE Patents (OSTI)

The invention is directed to a hydrogenated amorphous silicon PIN semiconductor device of hybrid glow discharge/reactive sputtering fabrication. The hybrid fabrication method is of advantage in providing an ability to control the optical band gap of the P and N layers, resulting in increased photogeneration of charge carriers and device output.

Moustakas, Theodore D. (Berkeley Heights, NJ); Morel, Don L. (Woodland Hills, CA); Abeles, Benjamin (Princeton, NJ)

1983-10-04T23:59:59.000Z

77

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

DOE Green Energy (OSTI)

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

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

1986-12-01T23:59:59.000Z

78

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

DOE Green Energy (OSTI)

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

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

1988-02-01T23:59:59.000Z

79

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

Science Conference Proceedings (OSTI)

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

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

2012-09-06T23:59:59.000Z

80

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

SciTech Connect

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

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

2012-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "wide band-gap semiconductor" from the National Library of EnergyBeta (NLEBeta).
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81

Excess charges in semiconductor nanocrystallites  

Science Conference Proceedings (OSTI)

The authors explore in this report the effects of excess electrons on the edge of the absorption spectrum of small semiconductor particles. The presence of these charges leads to strong bleaching of the absorption at the exciton region and to slight enhancement of the absorption on both sides of the bleaching. They show that the effect is independent of the origin of the charge; it occurs whether the charge is injected into the particle or only attached to its surface, and it appears even when the charge is deeply localized within the band gap. They conclude that the effect arises from the electric field associated with the charge and not from its presence in the band.

Laungdilok, C.; Lawless, D.; Cook, A.R.; Meisel, D. [Argonne National Lab., IL (United States). Chemistry Div.

1995-06-01T23:59:59.000Z

82

Gallium arsenide-based ternary compounds and multi-band-gap solar cell research. Annual subcontract report, 15 April 1988--14 June 1990  

DOE Green Energy (OSTI)

Aim of this contract is the achievement of a high-efficiency, low-cost solar cell. The basic approach to the problem is centered upon the heteroepitaxial growth of a III-V compound material onto a single-crystal silicon wafer. The growth technique employed is metalorganic chemical vapor deposition. The silicon wafer may serve as a mechanical substrate and ohmic contact for a single-junction device, or may contain a p-n junction of its own and form the bottom cell of a two junction tandem solar cell structure. The III-V material for the single-junction case is GaAs and for the two-junction case is either GaAlAs or GaAsP, either material having the proper composition to yield a band gap of approximately 1.7 eV. Results achieved in this contract include the following: (1) a 17.6% efficient GaAs-on-Si solar cell; (2) an 18.5% efficient GaAs-on-Si concentrator solar cell at 400 suns; (3) a 24.8% efficient GaAs-on-GaAs solar cell; (4) a 28.7% efficient GaAs-on-GaAs concentrator solar cell at 200 suns; (5) measurement of the effects of dislocation density and emitter doping on GaAs cells; and (6) improvements in the growth process to achieve reproducible thin AlGaAs window layers with low recombination velocities and environmental stability.

Vernon, S. [Spire Corp., Bedford, MA (United States)

1993-02-01T23:59:59.000Z

83

Gallium arsenide-based ternary compounds and multi-band-gap solar cell research. Final subcontract report, 1 April 1988--31 March 1990  

DOE Green Energy (OSTI)

This report describes work to achieve a high-efficiency, low-cost solar cell. The basic approach to the problem is centered upon the heteroepitaxial growth of a III-V compound material onto a single-crystal silicon wafer. The growth technique employed throughout this work is metal-organic chemical vapor deposition. The silicon wafer may serve as a mechanical substrate and ohmic contact for a single-junction device, or it may contain a p-n junction of its own and form the bottom cell of a two-junction tandem solar cell structure. The III-V material for the single-junction case is GaAs, and for the two-junction case it is either GaAlAs or GaAsP, either material having the proper composition to yield a band gap of approximately 1.7 eV. Results achieved in this contract include (1) a 17.6%-efficient GaAs-on-Si solar cell; (2) an 18.5%-efficient GaAs-on-Si concentrator solar cell at 400 suns; (3) a 24.8%-efficient GaAs-on-GaAs solar cell; (4) a 28.7%-efficient GaAs-on-GaAs concentrator solar cell at 200 suns; (5) the measurement of the effects of dislocation density and emitter doping on GaAs cells; and (6) improvements in the growth process to achieve reproducible thin AlGaAs window layers with low recombination velocities and environmental stability.

Vernon, S. [Spire Corp., Bedford, MA (United States)

1993-07-01T23:59:59.000Z

84

Oxide Ferromagnetic Semiconductors for Spin-Electronic Transprt  

SciTech Connect

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

Dr. R. K. Pandey, Cudworth Endowed Professor (Professor Emeritus of The Unviersity of Alabama) Ingram Endowed Professor, Ingram School of Engineering and Physics Department, Texas State University, San Marocs, TX78666

2008-11-24T23:59:59.000Z

85

Semiconductors News  

Science Conference Proceedings (OSTI)

... Nhan Nguyen demonstrates how he performs optical measurements on a graphene-insulator-semiconductor sample structure. ...

2010-05-24T23:59:59.000Z

86

Scanning tunneling microscopy reveals LiMnAs is a room temperature anti-ferromagnetic semiconductor  

SciTech Connect

We performed scanning tunneling microscopy and spectroscopy on a LiMnAs(001) thin film epitaxially grown on an InAs(001) substrate by molecular beam epitaxy. While the in situ cleavage exposed only the InAs(110) non-polar planes, the cleavage continued into the LiMnAs thin layer across several facets. We combined both topography and current mappings to confirm that the facets correspond to LiMnAs. By spectroscopy we show that LiMnAs has a band gap. The band gap evidenced in this study, combined with the known Neel temperature well above room temperature, confirms that LiMnAs is a promising candidate for exploring the concepts of high temperature semiconductor spintronics based on antiferromagnets.

Wijnheijmer, A. P.; Koenraad, P. M. [COBRA Inter-University Research Institute, Department of Applied Physics, Eindhoven University of Technology, P. O. Box 513, NL-5600 MB Eindhoven (Netherlands); Marti, X. [Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 3, 121 16 Prague 2 (Czech Republic); Institute of Physics ASCR, v.v.i., Cukrovarnicka 10, 162 53 Prague 6 (Czech Republic); Holy, V. [Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 3, 121 16 Prague 2 (Czech Republic); Cukr, M.; Novak, V. [Institute of Physics ASCR, v.v.i., Cukrovarnicka 10, 162 53 Prague 6 (Czech Republic); Jungwirth, T. [Institute of Physics ASCR, v.v.i., Cukrovarnicka 10, 162 53 Prague 6 (Czech Republic); School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD (United Kingdom)

2012-03-12T23:59:59.000Z

87

Semiconductor Nanoclusters as Potential Photocatalysts  

NLE Websites -- All DOE Office Websites (Extended Search)

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

88

Elements of Doping Engineering in Semiconductors  

DOE Green Energy (OSTI)

Using defect thermodynamics, we discuss physical factors that affect doping limits in semiconductors. The dependencies of the defect formation enthalpy on the atomic chemical potentials and on the electron Fermi energy are demonstrated. These dependencies, in particular on the Fermi energy, lead to spontaneous formation of charge-compensating defects that can limit doping. Experimental data compiled for III-V, II-VI, and I-III-VI2 compounds support this view and further provide insight into the connections among different host materials. We argue that what matters is not the magnitude of the band gap that determines the dopability of a material, but rather, the relative position of the conduction-band minimum (in the case of n-doping) and the valence-band maximum (in the case of p-doping) with respect to vacuum.

Zhang, S. B.; Wei, S.; Zunger, A.

1998-11-09T23:59:59.000Z

89

Semiconductor Analytics  

Science Conference Proceedings (OSTI)

... LED Lighting and Displays – Solar PV • Why Semiconductors? ... Potential Comments Solar PV 20.4 25-30% Politically driven. BP disaster will help. ...

2011-10-03T23:59:59.000Z

90

Utility-Scale Solar Power Converter: Agile Direct Grid Connect Medium Voltage 4.7-13.8 kV Power Converter for PV Applications Utilizing Wide Band Gap Devices  

SciTech Connect

Solar ADEPT Project: Satcon is developing a compact, lightweight power conversion device that is capable of taking utility-scale solar power and outputting it directly into the electric utility grid at distribution voltage levels—eliminating the need for large transformers. Transformers “step up” the voltage of the power that is generated by a solar power system so it can be efficiently transported through transmission lines and eventually “stepped down” to usable voltages before it enters homes and businesses. Power companies step up the voltage because less electricity is lost along transmission lines when the voltage is high and current is low. Satcon’s new power conversion devices will eliminate these heavy transformers and connect a utility-scale solar power system directly to the grid. Satcon’s modular devices are designed to ensure reliability—if one device fails it can be bypassed and the system can continue to run.

None

2012-01-25T23:59:59.000Z

91

Growth and Properties of the Dilute Bismide Semiconductor GaAs1-xBix a Complementary Alloy to the Dilute Nitrides  

DOE Green Energy (OSTI)

In this review we describe the growth and properties of the dilute bismide semiconductor alloy GaAs{sub 1-x}Bi{sub x} and show how its properties are in certain respects complementary to the dilute nitride alloy, GaN{sub y}As{sub 1-y}. Like the dilute nitrides the dilute bismides show a giant band gap bowing effect in which a small concentration of the alloying element has a disproportionate effect on the band gap, however in the case of the bismide the band gap reduction is associated with an increase in the energy of the valence band maximum (VBM) rather than a reduction in the energy of the conduction band minimum (CBM). Under standard GaAs growth conditions Bi acts as a surfactant with associated improvements in surface quality. In order to incorporate Bi, growth temperatures below 400 C are used with As{sub 2}/Ga flux ratios close to unity. The electron mobility of GaAs is only weakly affected by Bi alloying, in contrast to the dilute nitrides where the electron mobility decreases rapidly with N alloying. Bi alloying also produces a giant bowing effect in the spin orbit splitting in the valence band. Strong room temperature photoluminescence is observed. Prospects for future device applications of this new compound semiconductor alloy are discussed.

Tiedje, T.; Young, E. C.; Mascarenhas, A.

2008-01-01T23:59:59.000Z

92

Summary year 2: A study of potential high band-gap photovoltaic materials for a two step photon intermediate technique in fission energy conversion  

DOE Green Energy (OSTI)

The production of single crystal diamond thin films of large area would be a technological breakthrough for a variety of electronic and optical applications. In terms of the objectives of this contract, single crystal films would produce high quality doped regions and thus better barriers for energy conversion in the vacuum ultraviolet. To date, diamond single crystal films have been made homo-epitaxially on natural or synthetic diamond single crystals. As large single crystal diamond is prohibitively expensive, there is a need to find matching substrates for diamond heteropolarities. Cubic boron nitride has the diamond lattice structure and matches nearly perfectly the cell dimensions. However, large area cubic BN single crystal substrates are not available, as c-BN is stable, just like diamond, at high pressures and high temperatures only. The widely used Si substrates have a large lattice constant mismatch with diamond.

Prelas, M.A.; Charlson, E.J.; Charlson, E.M. [and others

1996-11-01T23:59:59.000Z

93

Wide Bandgap Semiconductor Material Growth and Characterization  

Science Conference Proceedings (OSTI)

Mar 6, 2013 ... Advanced Materials for Power Electronics, Power Conditioning, and Power .... due to a historical lack of native substrates and challenges in selectively ... have been optimized to provide equal growth rates of both polarities.

94

Wide Bandgap Semiconductors: Pursuing the Promise  

Science Conference Proceedings (OSTI)

... Motors: WBG materials will enable higher-efficiency, variable- speed drives in motors—pumps, fans, compressors, and HVAC systems—used ...

2013-05-08T23:59:59.000Z

95

Wide Bandgap Semiconductors: Pursuing the Promise  

Science Conference Proceedings (OSTI)

... Geothermal: WBG-based electronic sensors can withstand the harsh, high-pressure, and high-temperature environments of geothermal wells. ...

2013-05-08T23:59:59.000Z

96

Wide Bandgap Semiconductors Materials Growth and ...  

Science Conference Proceedings (OSTI)

Progress in 4H SiC Wafers and Epitaxy for Power Electronics Applications: Darren Hansen1; Mark Loboda1; Stephan Mueller1; Jie Zhang1; Bernd Thomas1

97

Research on high-band-gap materials and amorphous-silicon-based solar cells. Annual subcontract report, May 15, 1994--May 14, 1995  

DOE Green Energy (OSTI)

We have conducted a survey of thin BP:H and BPC:H films prepared by plasma deposition using phosphine, diborane, tri-methylboron, and hydrogen as precursor gases. The objective of this research is to find out whether such films might offer a superior window layer film for application to wide bandgap a-Si solar cells. The research has shown good optical properties in a-BP:H films, but electrical properties acceptable for use in window layers have not been demonstrated yet. We have also found an interesting, conductive and transparent BPC:H film in a remote deposition region of the reactor, but have been unable to transfer deposition of this film to the standard interelectrode region. We have developed our capability to deposit nip sequence amorphous silicon based solar cells, and have demonstrated an open circuit voltage greater than 0.7 V. We have continued our studies of built-in potentials in a-Si based solar cells using the electroabsorption technique, extending our measurements to include cells with wider bandgap intrinsic layers and Schottky barrier test structures. We have made the first time-of-flight drift mobility measurements on a-Si:H prepared by hot wire (HW) deposition. Initial work has shown that light-soaked HW material can have much better ambipolar diffusion lengths than the plasma-deposited material following extended light soaking. We have performed some theoretical work which addresses a difficulty in understanding photocarrier recombination in a-Si:H first identified by Marvin Silver. In particular, electron-hole recombination is much slower than expected from the well-known {open_quotes}diffusion-controlled{close_quotes} models for Onsager (geminate) recombination and Langevin recombination. This slowness is essential to the success of a-Si in solar cells, but is unexplained. We have done work on high field electron drift mobilities in a-Si:H and on the validity of the Einstein relation connecting the diffusion and drift of holes in a-Si:H.

Schiff, E.A.; Gu, Q.; Jiang, L.; Wang, Q. [Syracuse Univ., NY (United States)

1995-12-01T23:59:59.000Z

98

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

Science Conference Proceedings (OSTI)

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

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

2011-08-15T23:59:59.000Z

99

Stretchable semiconductor elements and stretchable electrical circuits  

DOE Patents (OSTI)

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

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

2009-07-07T23:59:59.000Z

100

Design of Shallow P-Type Dopants in ZnO: Preprint  

DOE Green Energy (OSTI)

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

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

2008-05-01T23:59:59.000Z

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


101

II-V Compound Semiconductors - Microsystems Science, Technology...  

NLE Websites -- All DOE Office Websites (Extended Search)

researched, developed and delivered include: A wide variety of specialty semiconductor lasers Integrated VCSEL-RCPD circuits (vertical-cavity surface-emitting lasers,...

102

Wide Bandgap Extrinsic Photoconductive Switches  

SciTech Connect

Photoconductive semiconductor switches (PCSS) have been investigated since the late 1970s. Some devices have been developed that withstand tens of kilovolts and others that switch hundreds of amperes. However, no single device has been developed that can reliably withstand both high voltage and switch high current. Yet, photoconductive switches still hold the promise of reliable high voltage and high current operation with subnanosecond risetimes. Particularly since good quality, bulk, single crystal, wide bandgap semiconductor materials have recently become available. In this chapter we will review the basic operation of PCSS devices, status of PCSS devices and properties of the wide bandgap semiconductors 4H-SiC, 6H-SiC and 2H-GaN.

Sullivan, J S

2012-01-17T23:59:59.000Z

103

Wafer-fused semiconductor radiation detector  

DOE Patents (OSTI)

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.

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

2002-01-01T23:59:59.000Z

104

Magnetoresistance of Ce{sub 3}Cu{sub 3}Sb{sub 4}: Ferromagnetic semiconductor (abstract)  

Science Conference Proceedings (OSTI)

Ferromagnetic semiconductors are an interesting class of materials. The first one, CrBr{sub 3} was discovered only in 1960. Magnetic semiconductors usually show a prominent peak in the resistivity and a very large negative magnetoresistance (MR) in the vicinity of T{sub c}, which is not well understood. Recently, we have reported Ce{sub 3}Cu{sub 3}Sb{sub 4} to be a ferromagnetic semiconductor with a T{sub c} of 10 K. To our knowledge, this is the first Ce system of this type and is a further addition to the rich varieties of ground states exhibited by Ce systems. Here, we report the MR studies on Ce{sub 3}Cu{sub 3}Sb{sub 4} in magnetic fields up to 8 T in the temperature range 4.2{endash}300 K. The resistivity of Ce{sub 3}Cu{sub 3}Sb{sub 4} shows a rise with decrease in temperature from 300 K exhibiting a peak at 19 K followed by a drastic fall at low temperatures. An activation type fit to the data gives a band-gap energy of 84 K. The resistivity peak is broadened considerably in a field of 8 T and the peak is found to shift to higher temperatures by about 10 K. The MR is small and negative ({lt}0.5{percent}) down to about 60 K and then gradually peaks to a large value of {minus}30{percent} at 12 K. The increased conduction in the vicinity of T{sub c} shows that the conduction band is influenced by the magnetic spins presumably due to s{endash}f interactions. The band-gap energy is found to remain constant even in a field as high as 8 T. This may rule out the magnetic polarons to be the cause of activation type of resistivity behavior. {copyright} {ital 1997 American Institute of Physics.}

Paulose, P.L.; Patil, S. [Tata Institute of Fundamental Research, Bombay (Mumbai)-5 (India)

1997-04-01T23:59:59.000Z

105

Mixed semiconductor nanocrystal compositions  

DOE Patents (OSTI)

Composition comprising one or more energy donors and one or more energy acceptors, wherein energy is transferred from the energy donor to the energy acceptor and wherein: the energy acceptor is a colloidal nanocrystal having a lower band gap energy than the energy donor; the energy donor and the energy acceptor are separated by a distance of 40 nm or less; wherein the average peak absorption energy of the acceptor is at least 20 meV greater than the average peak emission energy of the energy donor; and wherein the ratio of the number of energy donors to the number of energy acceptors is from about 2:1 to about 1000:1.

Maskaly, Garry R. (Los Alamos, NM); Schaller, Richard D. (Santa Fe, NM); Klimov, Victor I. (Los Alamos, NM)

2011-02-15T23:59:59.000Z

106

Photoelectrosynthesis at semiconductor electrodes  

DOE Green Energy (OSTI)

The general principles of photoelectrochemistry and photoelectrosynthesis are reviewed and some new developments in photoelectrosynthesis are discussed. Topics include energetics of semiconductor-electrolyte interfaces(band-edge unpinning); hot carrier injection at illuminated semiconductor-electrolyte junctions; derivatized semiconductor electrodes; particulate photoelectrochemical systems; layered compounds and other new materials; and dye sensitization. (WHK)

Nozik, A. J.

1980-12-01T23:59:59.000Z

107

Methods and devices for fabricating and assembling printable semiconductor elements  

DOE Patents (OSTI)

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

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

2013-05-14T23:59:59.000Z

108

Methods and devices for fabricating and assembling printable semiconductor elements  

DOE Patents (OSTI)

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

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

2011-07-19T23:59:59.000Z

109

Methods and devices for fabricating and assembling printable semiconductor elements  

DOE Patents (OSTI)

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

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

2009-11-24T23:59:59.000Z

110

Spire Semiconductor formerly Bandwidth Semiconductor LLC | Open Energy  

Open Energy Info (EERE)

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

111

Unitary lens semiconductor device  

DOE Patents (OSTI)

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.

Lear, Kevin L. (Albuquerque, NM)

1997-01-01T23:59:59.000Z

112

Uranium Oxide Semiconductors  

NLE Websites -- All DOE Office Websites (Extended Search)

of semiconductors, it would consume the annual production rate of depleted uranium from uranium enrichment facilities. For more information: PDF Semiconductive Properties of...

113

Theory of Semiconductor Laser Cooling .  

E-Print Network (OSTI)

??Recently laser cooling of semiconductors has received renewed attention, with the hope that a semiconductor cooler might be able to achieve cryogenic temperatures. In order… (more)

Rupper, Greg

2010-01-01T23:59:59.000Z

114

Atomic hydrogen cleaning of semiconductor photocathodes  

DOE Green Energy (OSTI)

Negative Electron Affinity (NEA) semiconductor photocathodes are widely used for the production of polarized electron beams, and are also useful for the production of high brightness electron beams which can be modulated at very high frequencies. Preparation of an atomically clean semiconductor surface is an essential step in the fabrication of a NEA photocathode. This cleaning step is difficult for certain semiconductors, such as the very thin materials which produce the highest beam polarization, and those which have tightly bound oxides and carbides. Using a small RF dissociation atomic hydrogen source, the authors have reproducibly cleaned GaAs wafers which have been only degreased prior to installation in vacuum. They have consistently prepared very high quantum efficiency photocathodes following atomic hydrogen cleaning. Details of their apparatus and most recent results are presented.

Sinclair, C.K.; Poelker, B.M.; Price, J.S. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

1997-06-01T23:59:59.000Z

115

Ferromagnetism in Oxide Semiconductors  

SciTech Connect

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

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

2006-11-01T23:59:59.000Z

116

Photoelectrochemical etching of semiconductors  

Science Conference Proceedings (OSTI)

Photoelectrochemical (PEC) etching of III-V semiconductors has been used to fabricate unique structures in electronic and photonic devices, such as integral lenses on light-emitting diodes, gratings on laser structures, and through-wafer via connections ...

P. A. Kohl

1998-09-01T23:59:59.000Z

117

TTRDC - News  

NLE Websites -- All DOE Office Websites (Extended Search)

Hosted Consortium to Address Wide Band Gap Materials for Improved Power Electronics Devices Argonne researchers Ted Bohn and Ann Schlenker participated in the Wide Band Gap...

118

Method of doping a semiconductor  

DOE Patents (OSTI)

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.

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

1983-01-01T23:59:59.000Z

119

Blasting detonators incorporating semiconductor bridge technology  

SciTech Connect

The enormity of the coal mine and extraction industries in Russia and the obvious need in both Russia and the US for cost savings and enhanced safety in those industries suggests that joint studies and research would be of mutual benefit. The author suggests that mine sites and well platforms in Russia offer an excellent opportunity for the testing of Sandia`s precise time-delay semiconductor bridge detonators, with the potential for commercialization of the detonators for Russian and other world markets by both US and Russian companies. Sandia`s semiconductor bridge is generating interest among the blasting, mining and perforation industries. The semiconductor bridge is approximately 100 microns long, 380 microns wide and 2 microns thick. The input energy required for semiconductor bridge ignition is one-tenth the energy required for conventional bridgewire devices. Because semiconductor bridge processing is compatible with other microcircuit processing, timing and logic circuits can be incorporated onto the chip with the bridge. These circuits can provide for the precise timing demanded for cast effecting blasting. Indeed tests by Martin Marietta and computer studies by Sandia have shown that such precise timing provides for more uniform rock fragmentation, less fly rock, reduce4d ground shock, fewer ground contaminants and less dust. Cost studies have revealed that the use of precisely timed semiconductor bridges can provide a savings of $200,000 per site per year. In addition to Russia`s vast mineral resources, the Russian Mining Institute outside Moscow has had significant programs in rock fragmentation for many years. He anticipated that collaborative studies by the Institute and Sandia`s modellers would be a valuable resource for field studies.

Bickes, R.W. Jr.

1994-05-01T23:59:59.000Z

120

Hydrogen in semiconductors  

DOE Green Energy (OSTI)

After an incubation'' period in the 1970's and early 80's, during which the first hydrogen related centers were discovered and characterized in ultra-pure germanium, a sharp increase of research activity occurred after the discovery of shallow acceptor passivation in crystalline silicon. The aim of this review is to convey an insight into the rich, multifaceted physics and materials science which has emerged from the vast variety of experimental and theoretical studies of hydrogen in semiconductors. In order to arrive at the current understanding of hydrogen related phenomena in a logical way, each chapter will start with a brief review of the major experimental and theoretical advances of the past few years. Those who are interested to learn more about this fascinating area of semiconductor research are referred to reviews, to a number of conference proceedings volumes, and to an upcoming book which will contain authoritative chapters on most aspects of hydrogen in crystalline semiconductors. Some of the early art of semiconductor device processing can finally be put on a scientific foundation and new ways of arriving at advanced device structures begin to use what we have learned from the basic studies of hydrogen in semiconductors. 92 refs., 8 figs.

Haller, E.E. (California Univ., Berkeley, CA (USA) Lawrence Berkeley Lab., CA (USA))

1990-06-01T23:59:59.000Z

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


121

A 250 GHz photonic band gap gyrotron amplifier  

E-Print Network (OSTI)

This thesis reports the theoretical and experimental investigation of a novel gyrotron traveling-wave-tube (TWT) amplifier at 250 GHz. The gyrotron amplifier designed and tested in this thesis has achieved a peak small ...

Nanni, Emilio A. (Emilio Alessandro)

2013-01-01T23:59:59.000Z

122

Incorporation of Furan into Low Band-Gap Polymers for ...  

and Departments of Chemistry and Chemical Engineering, UniVersity of California, Berkeley, California 94720-1460, United States

123

Special purpose modes in photonic band gap fibers - Energy ...  

Solar Thermal; Startup ... Partners (27) Visual Patent Search; Success Stories; News; Events; Special purpose modes in ... Issued: April 2, 2013: ...

124

Experimental study of photonic band gap accelerator structures  

E-Print Network (OSTI)

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

Marsh, Roark A

2009-01-01T23:59:59.000Z

125

Opals, Photonic Band Gap Materials, Pleochroic Refraction, and ...  

Science Conference Proceedings (OSTI)

Improved Performance of a Fluorescent Blue Organic Light Emitting Diode with Hole Blocking Materials as Dopants for Transport Layers · Luminescence of the ...

126

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

E-Print Network (OSTI)

Jul 10, 2009 ... Due to the lack of fundamental length scale in Maxwell's equations, it can be shown that the magnitude of the ...... quantum chemistry. In Proceedings of the ... Handbook of semidefinite programming: theory, algorithms, and ...

127

Light-matter Interactions in Semiconductor Nanostructures  

Science Conference Proceedings (OSTI)

Light-matter interactions in Semiconductor Nanostructures. ... We investigate the interaction of light with semiconductor-based nanostructures. ...

2012-05-30T23:59:59.000Z

128

Multiband semiconductor compositions for photovoltaic devices  

DOE Patents (OSTI)

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

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

2012-03-06T23:59:59.000Z

129

Kansas Advanced Semiconductor Project  

SciTech Connect

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

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

2007-09-21T23:59:59.000Z

130

Amorphous semiconductor solar cell  

SciTech Connect

A solar cell comprising a back electrical contact, amorphous silicon semiconductor base and junction layers and a top electrical contact includes in its manufacture the step of heat treating the physical junction between the base layer and junction layer to diffuse the dopant species at the physical junction into the base layer.

Dalal, Vikram L. (Newark, DE)

1981-01-01T23:59:59.000Z

131

Compound semiconductor MOSFETs  

Science Conference Proceedings (OSTI)

Enhancement mode, high electron mobility MOSFET devices have been fabricated using an oxide high-@k gate dielectric stack developed using molecular beam epitaxy. A template layer of Ga"2O"3, initially deposited on the surface of the III-V device unpins ... Keywords: Compound semiconductors, GaAs gate dielectric, III-V MOSFETs

R. Droopad; K. Rajagopalan; J. Abrokwah; P. Zurcher; M. Passlack

2007-09-01T23:59:59.000Z

132

Novel room temperature ferromagnetic semiconductors  

SciTech Connect

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

Gupta, Amita

2004-11-01T23:59:59.000Z

133

Definition: Semiconductor | Open Energy Information  

Open Energy Info (EERE)

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

134

Light amplification using semiconductors  

Science Conference Proceedings (OSTI)

During the summer of 1953, John von Neumann discussed his ideas concerning light amplification using semiconductors with Edward Teller. In September of that year, von Neumann sent a manuscript containing his ideas and calculations on this subject to Teller for his comments. To the best of our knowledge, von Neumann did not take time to work further on these ideas, and the manuscript remained unpublished. These previously unpublished writings of John von Neumann on the subject of light amplification in semiconductors are printed as a service to the laser community. While von Neumann's original manuscript and his letter to Teller are available to anyone who visits the Library of Congress, it is much more convenient to have this paper appear in an archival journal.

Dupuis, R.D.

1987-06-01T23:59:59.000Z

135

Isotopically controlled semiconductors  

SciTech Connect

The following article is an edited transcript based on the Turnbull Lecture given by Eugene E. Haller at the 2005 Materials Research Society Fall Meeting in Boston on November 29, 2005. The David Turnbull Lectureship is awarded to recognize the career of a scientist who has made outstanding contributions to understanding materials phenomena and properties through research, writing, and lecturing, as exemplified by the life work of David Turnbull. Haller was named the 2005 David Turnbull Lecturer for his 'pioneering achievements and leadership in establishing the field of isotopically engineered semiconductors; for outstanding contributions to materials growth, doping and diffusion; and for excellence in lecturing, writing, and fostering international collaborations'. The scientific interest, increased availability, and technological promise of highly enriched isotopes have led to a sharp rise in the number of experimental and theoretical studies with isotopically controlled semiconductor crystals. This article reviews results obtained with isotopically controlled semiconductor bulk and thin-film heterostructures. Isotopic composition affects several properties such as phonon energies, band structure, and lattice constant in subtle, but, for their physical understanding, significant ways. Large isotope-related effects are observed for thermal conductivity in local vibrational modes of impurities and after neutron transmutation doping. Spectacularly sharp photoluminescence lines have been observed in ultrapure, isotopically enriched silicon crystals. Isotope multilayer structures are especially well suited for simultaneous self- and dopant-diffusion studies. The absence of any chemical, mechanical, or electrical driving forces makes possible the study of an ideal random-walk problem. Isotopically controlled semiconductors may find applications in quantum computing, nanoscience, and spintronics.

Haller, Eugene E.

2006-06-19T23:59:59.000Z

136

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

Science Conference Proceedings (OSTI)

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.

GLASER, EVAN

2012-08-17T23:59:59.000Z

137

Chemical vapor deposition of amorphous semiconductor films. Final subcontract report  

DOE Green Energy (OSTI)

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

Rocheleau, R.E.

1984-12-01T23:59:59.000Z

138

Method of passivating semiconductor surfaces  

DOE Patents (OSTI)

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

Wanlass, Mark W. (Golden, CO)

1990-01-01T23:59:59.000Z

139

Method of passivating semiconductor surfaces  

DOE Patents (OSTI)

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.

Wanlass, M.W.

1990-06-19T23:59:59.000Z

140

High power semiconductor laser diode arrays  

SciTech Connect

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

Cross, P.S.

1986-08-15T23:59:59.000Z

Note: This page contains sample records for the topic "wide band-gap semiconductor" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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141

Isotopically controlled semiconductors  

SciTech Connect

Semiconductor bulk crystals and multilayer structures with controlled isotopic composition have attracted much scientific and technical interest in the past few years. Isotopic composition affects a large number of physical properties, including phonon energies and lifetimes, bandgaps, the thermal conductivity and expansion coefficient and spin-related effects. Isotope superlattices are ideal media for self-diffusion studies. In combination with neutron transmutation doping, isotope control offers a novel approach to metal-insulator transition studies. Spintronics, quantum computing and nanoparticle science are emerging fields using isotope control.

Haller, Eugene E.

2001-12-21T23:59:59.000Z

142

Layered semiconductor neutron detectors  

SciTech Connect

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.

Mao, Samuel S; Perry, Dale L

2013-12-10T23:59:59.000Z

143

Semiconductor devices incorporating multilayer interference regions  

DOE Patents (OSTI)

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

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

1987-08-31T23:59:59.000Z

144

Variable temperature semiconductor film deposition  

DOE Patents (OSTI)

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

Li, X.; Sheldon, P.

1998-01-27T23:59:59.000Z

145

Nanostructures, magnetic semiconductors and spintronics  

Science Conference Proceedings (OSTI)

The aim of this paper is to give a brief overview of recent advances in the area of semiconductor nanomaterials, which represent extremely promising applications for materials with the spin-polarized transport of the charge carriers. It is shown on the ... Keywords: Magnetic properties, Nanostructure, Semiconductor, Spin-polarized transport, Spintronics

Paata Kervalishvili; Alexander Lagutin

2008-08-01T23:59:59.000Z

146

Mesoscopic Magnetic/Semiconductor Heterostructures  

Science Conference Proceedings (OSTI)

We report the experimental results of Fe and Fe3O4 nanostructures on GaAs(100) surfaces and hybrid Ferromagnetic/Semiconductor/Ferromagnetic (FM/SC/FM) spintronic devices. Element specific x-ray magnetic circular dichroism (XMCD) ... Keywords: Epitaxial ferromagnetic thin film, ferromagnetic/semiconductor hybrid structures, spintronics

Yong Bing Xu; E. Ahmad; Yong Xiong Lu; J. S. Claydon; Ya Zhai; G. van der Laan

2006-09-01T23:59:59.000Z

147

Process for producing chalcogenide semiconductors  

DOE Patents (OSTI)

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

Noufi, R.; Chen, Y.W.

1985-04-30T23:59:59.000Z

148

Method Of Transferring Strained Semiconductor Structures  

NLE Websites -- All DOE Office Websites (Extended Search)

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

149

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

Office of Scientific and Technical Information (OSTI)

FederalState Programs PFC ReductionClimate Partnership for the Semiconductor Industry Launched in 1996 in collaboration with the Semiconductor Industry Association, EPA's PFC...

150

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

NLE Websites -- All DOE Office Websites (Extended Search)

Compound Semiconductor Science and Technology Thrust The Physical, Chemical, and Nano Sciences Center's vision for Compound Semiconductors is to develop the science of compound...

151

Hydrogen in compound semiconductors  

DOE Green Energy (OSTI)

Progress in the understanding of hydrogen and its interactions in III/V and II/VI compound semiconductors is reviewed. Donor, acceptor and deep level passivation is well established in III/V compounds based on electrical measurements and on spectroscopic studies. The hydrogen donor levels in GaAs and GaP are estimated to lie near E{sub v}+0.5 eV and E{sub v}+0.3 eV, respectively. Arsenic acceptors have been passivated by hydrogen in CdTe and the very first nitrogen-hydrogen local vibrational model spectra in ZnSe have been reported. This long awaited result may lead to an explanation for the poor activation of nitrogen acceptors in ZnSe grown by techniques which involve high concentrations of hydrogen.

Haller, E.E.

1993-05-01T23:59:59.000Z

152

Semiconductor radiation detector  

DOE Patents (OSTI)

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

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

2010-03-30T23:59:59.000Z

153

Thermal Conductivity of Polycrystalline Semiconductors and Ceramics  

E-Print Network (OSTI)

industries, polycrystalline semiconductors and ceramics havelaser industry, people are also seeking good ceramic laser

Wang, Zhaojie

2012-01-01T23:59:59.000Z

154

Simulating nanoscale semiconductor devices.  

SciTech Connect

The next generation of electronic devices will be developed at the nanoscale and molecular level, where quantum mechanical effects are observed. These effects must be accounted for in the design process for such small devices. One prototypical nanoscale semiconductor device under investigation is a resonant tunneling diode (RTD). Scientists are hopeful the quantum tunneling effects present in an RTD can be exploited to induce and sustain THz frequency current oscillations. To simulate the electron transport within the RTD, the Wigner-Poisson equations are used. These equations describe the time evolution of the electrons distribution within the device. In this paper, this model and a parameter study using this model will be presented. The parameter study involves calculating the steady-state current output from the RTD as a function of an applied voltage drop across the RTD and also calculating the stability of that solution. To implement the parameter study, the computational model was connected to LOCA (Library of Continuation Algorithms), a part of Sandia National Laboratories parallel solver project, Trilinos. Numerical results will be presented.

Salinger, Andrew Gerhard; Zhao, P. (North Carolina State University, Raleigh, NC); Woolard, D. L. (U. S. Army Research Laboratory, NC); Kelley, C. Tim (North Carolina State University, Raleigh, NC); Lasater, Matthew S. (North Carolina State University, Raleigh, NC)

2005-03-01T23:59:59.000Z

155

Controlled buckling structures in semiconductor interconnects and nanomembranes for stretchable electronics  

DOE Patents (OSTI)

In an aspect, the present invention provides stretchable, and optionally printable, components such as semiconductors and electronic circuits capable of providing good performance when stretched, compressed, flexed or otherwise deformed, and related methods of making or tuning such stretchable components. Stretchable semiconductors and electronic circuits preferred for some applications are flexible, in addition to being stretchable, and thus are capable of significant elongation, flexing, bending or other deformation along one or more axes. Further, stretchable semiconductors and electronic circuits of the present invention are adapted to a wide range of device configurations to provide fully flexible electronic and optoelectronic devices.

Rogers, John A. (Champaign, IL); Meitl, Matthew (Raleigh, NC); Sun, Yugang (Naperville, IL); Ko, Heung Cho (Urbana, IL); Carlson, Andrew (Urbana, IL); Choi, Won Mook (Champaign, IL); Stoykovich, Mark (Dover, NH); Jiang, Hanqing (Urbana, IL); Huang, Yonggang (Glencoe, IL); Nuzzo, Ralph G. (Champaign, IL); Lee, Keon Jae (Tokyo, JP); Zhu, Zhengtao (Rapid City, SD); Menard, Etienne (Durham, NC); Khang, Dahl-Young (Seoul, KR); Kan, Seong Jun (Daejeon, KR); Ahn, Jong Hyun (Suwon, KR); Kim, Hoon-sik (Champaign, IL)

2012-07-10T23:59:59.000Z

156

Synchronization in semiconductor laser rings  

E-Print Network (OSTI)

We examine the dynamics of semiconductor lasers coupled in a ring configuration. The lasers, which have stable output intensity when isolated, behave chaotically when coupled unidirectionally in a closed chain. In this way, we show that neither feedback nor bidirectional coupling is necessary to induce chaotic dynamics at the laser output. We study the synchronization phenomena arising in this particular coupling architecture, and discuss its possible application to chaos-based communications. Next, we extend the study to bidirectional coupling and propose an appropriate technique to optical chaos encryption/decryption in closed chains of mutually coupled semiconductor lasers.

Javier M. Buldu; M. C. Torrent; Jordi Garcia-Ojalvo

2006-10-06T23:59:59.000Z

157

Correlated exciton dynamics in semiconductor nanostructures  

E-Print Network (OSTI)

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 ...

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

2013-01-01T23:59:59.000Z

158

Innovations in Semiconductor Devices for Exascale ...  

Science Conference Proceedings (OSTI)

Innovations in Semiconductor Devices for Exascale Computing. TC Chen IBM Fellow and Vice President of Science and ...

2010-10-05T23:59:59.000Z

159

Data mining solves tough semiconductor manufacturing problems  

Science Conference Proceedings (OSTI)

Keywords: data mining, machine learning, manufacturing optimization, neural networks, pattern recognition, rule induction, self organizing maps, semiconductor yield enhancement

Mike Gardner; Jack Bieker

2000-08-01T23:59:59.000Z

160

Sandia National Labs: PCNSC: Departments: Semiconductor Material...  

NLE Websites -- All DOE Office Websites (Extended Search)

Semiconductor Material & Device Sciences > Advanced Materials Sciences > Lasers, Optics & Remote Sensing Energy Sciences Small Science Cluster Business Office News Partnering...

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


161

Bottoms Up: Better Organic Semiconductors for Printable ...  

Science Conference Proceedings (OSTI)

... A patent from British researchers in 2005 offered a promising compromise: blend the small semiconductor molecules in with the polymer. ...

2012-10-18T23:59:59.000Z

162

Semiconductor assisted metal deposition for nanolithography applications  

DOE Patents (OSTI)

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

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

2002-01-01T23:59:59.000Z

163

Robust Capacity Planning in Semiconductor Manufacturing  

E-Print Network (OSTI)

Oct 3, 2001 ... Abstract: We present a stochastic programming approach to capacity planning under demand uncertainty in semiconductor manufacturing.

164

Economic Impact of Measurement in the Semiconductor ...  

Science Conference Proceedings (OSTI)

... semiconductors are the workhorses that take electric voltage and engender ... the distance between lines of memory (dynamic random access ...

2012-10-09T23:59:59.000Z

165

NNSA-Wide  

National Nuclear Security Administration (NNSA)

NNSA-Wide Fiscal Year 2012 Year-End Workforce Diversity Office of Civil Rights NA-1.2 Albuquerque Complex PO Box 5400 Albuquerque, NM 87185 Phone (505) 845-5517 Fax (505) 845-4963...

166

Research on defects and transport in amorphous-silicon-based semiconductors. Final subcontract report, 20 February 1991--19 April 1994  

DOE Green Energy (OSTI)

This report describes work on three individual tasks as follows. (1) Electron and hole drift measurements in a-Si{sub 1-x}Ge{sub x}:H and a-Si{sub 1-x}C{sub x}:H p-i-n solar cells. Multijunction solar cells incorporating modified band gap a-Si:H in a triple-junction structure are generally viewed as the most promising avenue for achieving an amorphous silicon-based solar call with 15% stabilized conversion efficiency. The specific objective of this task was to document the mobilities and deep-trapping mobility-lifetime products for electrons and holes in a-Si{sub 1-x}Ge{sub x}:H and a-Si{sub 1-x}C{sub x}:H alloys materials. (2) Electroabsorption measurements and built-in potential (V{sub bi}) in solar cells. V{sub bi} in a p-i-n solar call may be limiting the open-circuit voltage (V{sub oc}) in wide-band-gap cells (E{sub g} > 1.8 eV) currently under investigation as the top cell for 15% triple junction devices. The research addressed four issues that need to be resolved before the method can yield an error less than 0.1 V for V{sub bi}. The details are presented in this report. (3) Defect relaxation and Shockley-Read kinetics in a-Si:H. Quantitative modeling of solar cells is usually based on Shockley-Read kinetics.`` An important assumption of this approach is that the rate of emission of a photocarrier trapped on a defect is independent of quasi-Fermi level location.

Schiff, E.A.; Antoniadis, H.; Gu, Q.; Lee, J.K.; Wang, Q.; Zafar, S. [Syracuse Univ., NY (United States)

1994-09-01T23:59:59.000Z

167

Mechanical scriber for semiconductor devices  

DOE Patents (OSTI)

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

Lin, P.T.

1985-03-05T23:59:59.000Z

168

Mechanical scriber for semiconductor devices  

DOE Patents (OSTI)

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

Lin, Peter T. (East Brunswick, NJ)

1985-01-01T23:59:59.000Z

169

Wide-Gap Thin Film Si n-i-p Solar Cells Deposited by Hot-Wire CVD: Preprint  

DOE Green Energy (OSTI)

High-voltage wide bandgap thin-film Si n-i-p solar cells have been made using the hot-wire chemical vapor deposition (HWCVD) technique. The best open-circuit voltage (Voc) has exceeded 0.94 V in solar cells using HWCVD in the entire n-i-p structure. A Voc of 0.97V has been achieved using HWCVD in the n and i layers and plasma-enhanced (PE) CVD for the p layer. The high voltages are attributed to the wide-gap i layer and an improved p/i interface. The wide-gap i layer is obtained by using low substrate temperatures and sufficient hydrogen dilution during the growth of the i layer to arrive at the amorphous-to-microcrystalline phase transition region. The optical band gap (E04) of the i layer is found to be 1.90 eV. These high-voltage cells also exhibit good fill factors exceeding 0.7 with short-circuit-current densities of 8 to 10 mA/cm2 on bare stainless steel substrates. We have also carried out photoluminescence (PL) spectroscopy studies and found a correlation between Voc and the PL peak energy position.

Wang, Q.; Iwaniczko, E.; Yang, J.; Lord, K.; Guha, S.; Wang, K.; Han, D.

2002-05-01T23:59:59.000Z

170

A comparative study of semiconductor-based plasmonic metamaterials  

E-Print Network (OSTI)

Recent metamaterial (MM) research faces several problems when using metal-based plasmonic components as building blocks for MMs. The use of conventional metals for MMs is limited by several factors: metals such as gold and silver have high losses in the visible and near-infrared (NIR) ranges and very large negative real permittivity values, and in addition, their optical properties cannot be tuned. These issues that put severe constraints on the device applications of MMs could be overcome if semiconductors are used as plasmonic materials instead of metals. Heavily doped, wide bandgap oxide semiconductors could exhibit both a small negative real permittivity and relatively small losses in the NIR. Heavily doped oxides of zinc and indium were already reported to be good, low loss alternatives to metals in the NIR range. Here, we consider these transparent conducting oxides (TCOs) as alternative plasmonic materials for many specific applications ranging from surface-plasmon-polariton waveguides to MMs with hype...

Naik, Gururaj V; 10.1016/j.metmat.2010.11.001

2011-01-01T23:59:59.000Z

171

Power Electronics in the Semiconductor Fabrication Industry  

Science Conference Proceedings (OSTI)

This report provides utility marketing and account executives and engineering staff with fundamental information about the use of power electronics systems in semiconductor fabrication equipment. It details the power electronics systems used in typical semiconductor production equipment as well as current topology and system compatibility issues. Finally, the report outlines how power electronics will serve future advances in the semiconductor industry and how utilities can help the industry make their e...

1999-03-10T23:59:59.000Z

172

Optical devices featuring textured semiconductor layers  

DOE Patents (OSTI)

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

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

2012-08-07T23:59:59.000Z

173

Optical devices featuring textured semiconductor layers  

DOE Patents (OSTI)

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

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

2011-10-11T23:59:59.000Z

174

Lattice matched semiconductor growth on crystalline ...  

Methods of fabricating a semiconductor layer or device and said devices are disclosed. The methods include but are not limited to providing a metal or ...

175

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

Office of Scientific and Technical Information (OSTI)

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

176

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 Spinoff Applications SBIRSTTR...

177

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 Spinoff Applications Spinoff...

178

Stangl Semiconductor Equipment AG | Open Energy Information  

Open Energy Info (EERE)

Solar Product German manufacturer of wet chemistry systems for processing silicon and thin-film solar cells. References Stangl Semiconductor Equipment AG1 LinkedIn...

179

Visitors Far and Wide  

NLE Websites -- All DOE Office Websites (Extended Search)

4 4 Visitors Far and Wide From left: Minister Danilov-Daniljan, Evan Mills (Assistant Director, Center for Building Science), Victoria Mats (interpreter and Soviet energy analyst), and Len Grossman (PG&E Energy Center) tour the PG&E Energy Center in San Francisco. The Russian Minister of Ecology and Natural Resources, Victor I. Danilov-Daniljan, spent three days in California as the Center's guest. The Minister presented information on current Soviet energy and environmental dilemmas and participated in a day-long roundtable discussion with representatives of major utilities, manufacturers of energy-efficient technologies, energy regulators, nongovernmental organizations, and Center scientists. Julian Aizenberg, one of the former Soviet Union's (FSU) foremost lighting

180

Island Wide Management Corporation  

Office of Legacy Management (LM)

9 1986 9 1986 Island Wide Management Corporation 3000 Marcus Avenue Lake Success, New York 11042 Dear Sir or Madam: I am sending you this letter and the enclosed information as you have been identified by L. I. Trinin of Glick Construction Company as the representatives of the owners of the property that was formerly the site of the Sylvania-Corning Nuclear Corporation in Bayside, New York. The Department of Energy is evaluating the radiological condition of sites that were utilized under the Manhattan Engineer District and/or the Atomic Energy Commission in the early years of nuclear energy development to determine whether they need remedial action and whether the Department has authority to perform such action. As you may know, the former Sylvania-Corning Corporation Bayside site was identified as one such site.

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


181

Biomimetic Dye Molecules for Solar Cells  

NLE Websites -- All DOE Office Websites (Extended Search)

positive electrode (lower blue arrows). At least four molecular levels are available for optimization, compared to only the band gap for solid-state semiconductors. Spectroscopy...

182

Stable surface passivation process for compound semiconductors  

DOE Patents (OSTI)

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.

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

2001-01-01T23:59:59.000Z

183

Preparation of a semiconductor thin film  

SciTech Connect

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

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

1998-01-01T23:59:59.000Z

184

Semiconductor liquid-junction solar cell  

DOE Patents (OSTI)

A semiconductor liquid junction photocell in which the photocell is in the configuration of a light concentrator and in which the electrolytic solution both conducts current and facilitates the concentration of incident solar radiation onto the semiconductor. The photocell may be in the configuration of a non-imaging concentrator such as a compound parabolic concentrator, or an imaging concentrator such as a lens.

Parkinson, B.A.

1982-10-29T23:59:59.000Z

185

Business Case Slide 28: High-Value: Semiconductors - Program...  

NLE Websites -- All DOE Office Websites (Extended Search)

Semiconductors - Program Focus Previous Slide Next Slide Table of Contents High-Value: Semiconductors - Program Focus Measurement of DUO2 transistor properties at ORNL Measurement...

186

Semiconductor switch geometry with electric field shaping  

DOE Patents (OSTI)

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.

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

1994-01-01T23:59:59.000Z

187

the World Wide Web  

Office of Scientific and Technical Information (OSTI)

technical report has been made technical report has been made electronically available on the World Wide Web through a contribution from Walter L. Warnick In honor of Enrico Fermi Leader of the first nuclear reactor, Nobel Prize winner, and visionary technologist Dr. Warnick is delighted to be the first sponsor for posting a Department of Energy technical report and making it broadly available Office of Scientific and Technical Information Office of Science U.S. Department of Energy September 2008 osti.gov U N I T E D S T A T E S A T O M I C E N E R G Y C O M M I S S I O N AECD-3269 EXPERIMENTAL PRODUCTION OF A DNERGENT CHAIN REACTION BY E. Fermi January 4, 1952 [TIS Issuance ate] [chicago University] - T e c h n i c a l I n f o r m a t i o n S e r v i c e , O a k Ridge, T e n n e s s e e r ABSTRACTS Description of the construction and operation of the chain

188

Energy Management in Semiconductor Cleanrooms  

NLE Websites -- All DOE Office Websites (Extended Search)

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

189

Phosphorus doping a semiconductor particle  

DOE Patents (OSTI)

A method of phosphorus doping a semiconductor particle using ammonium phosphate is disclosed. A p-doped silicon sphere is mixed with a diluted solution of ammonium phosphate having a predetermined concentration. These spheres are dried with the phosphorus then being diffused into the sphere to create either a shallow or deep p-n junction. A good PSG glass layer is formed on the surface of the sphere during the diffusion process. A subsequent segregation anneal process is utilized to strip metal impurities from near the p-n junction into the glass layer. A subsequent HF strip procedure is then utilized to removed the PSG layer. Ammonium phosphate is not a restricted chemical, is inexpensive, and does not pose any special shipping, handling, or disposal requirement. 1 fig.

Stevens, G.D.; Reynolds, J.S.

1999-07-20T23:59:59.000Z

190

Boron doping a semiconductor particle  

DOE Patents (OSTI)

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

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

1998-06-09T23:59:59.000Z

191

Semiconductor processing with excimer lasers  

DOE Green Energy (OSTI)

The advantages of pulsed excimer lasers for semiconductor processing are reviewed. Extensive comparisons of the quality of annealing of ion-implanted Si obtained with XeCl and ruby lasers have been made. The results indicate that irrespective of the large differences in the optical properties of Si at uv and visible wavelengths, the efficiency of usage of the incident energy for annealing is comparable for the two lasers. However, because of the excellent optical beam quality, the XeCl laser can provide superior control of the surface melting and the resulting junction depth. Furthermore, the concentrations of electrically active point defects in the XeCl laser annealed region are 2 to 3 orders of magnitude lower than that obtained from ruby or Nd:YAG lasers. All these results seem to suggest that XeCl lasers should be suitable for fabricating not only solar cells but also the more advanced device structures required for VLSI or VHSIC applications.

Young, R.T.; Narayan, J.; Christie, W.H.; van der Leeden, G.A.; Rothe, D.E.; Cheng, L.J.

1983-01-01T23:59:59.000Z

192

Heating device for semiconductor wafers  

DOE Patents (OSTI)

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

Vosen, S.R.

1999-07-27T23:59:59.000Z

193

Heating device for semiconductor wafers  

DOE Patents (OSTI)

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

Vosen, Steven R. (Berkeley, CA)

1999-01-01T23:59:59.000Z

194

Semiconductor Nanoclusters as Potential Photocatalysts  

NLE Websites -- All DOE Office Websites (Extended Search)

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

195

A World Wide Web Update  

NLE Websites -- All DOE Office Websites (Extended Search)

A World Wide Web Update The Center for Building Science now has a World Wide Web homepage accessible from the general LBL homepage. Through WWW and the Mosaic browser, Internet...

196

Mospec Semiconductor Corp | Open Energy Information  

Open Energy Info (EERE)

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

197

Gaining creative control over semiconductor nanowires  

NLE Websites -- All DOE Office Websites (Extended Search)

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

198

High Aspect Ratio Semiconductor Heterojunction Solar Cells  

E-Print Network (OSTI)

High Aspect Ratio Semiconductor Heterojunction Solar Cells Haoting Shen Prof. Redwing's Research and in-situ dopant for Si nanowires Y. Ke, X.J. Weng, J.M. Redwing, C.M. Eichfeld, T.R. Swisher, S

Yener, Aylin

199

Semiconductor-nanocrystal/conjugated polymer thin films  

DOE Patents (OSTI)

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.

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

200

Developing New Nanoprobes from Semiconductor Nanocrystals  

E-Print Network (OSTI)

Water-Soluble Silica- Coated CdSe/ZnS Semiconductor QuantumEnhanced Luminescence of CdSe Quantum Dots on Gold Colloids.CdS/ZnS shells on colloidal CdSe nanorods. Journal Of The

Fu, Aihua

2006-01-01T23:59:59.000Z

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201

Hemlock Semiconductor Corp HSC | Open Energy Information  

Open Energy Info (EERE)

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

202

Climate VISION: Private Sector Initiatives: Semiconductors  

Office of Scientific and Technical Information (OSTI)

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

203

Optical temperature indicator using thermochromic semiconductors  

DOE Patents (OSTI)

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

Kronberg, J.W.

1995-01-01T23:59:59.000Z

204

Anomalous Charge Transport in Disordered Organic Semiconductors  

Science Conference Proceedings (OSTI)

Anomalous charge carrier transport in disordered organic semiconductors is studied using fractional differential equations. The connection between index of fractional derivative and dispersion exponent is examined from the perspective of fractional Fokker-Planck equation and its link to the continuous time random walk formalism. The fractional model is used to describe the bi-scaling power-laws observed in the time-of flight photo-current transient data for two different types of organic semiconductors.

Muniandy, S. V.; Woon, K. L. [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Choo, K. Y. [Faculty of Engineering, Multimedia University, 63100 Cyberjaya, Selangor (Malaysia)

2011-03-30T23:59:59.000Z

205

Optical devices featuring nonpolar textured semiconductor layers  

DOE Patents (OSTI)

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.

Moustakas, Theodore D; Moldawer, Adam; Bhattacharyya, Anirban; Abell, Joshua

2013-11-26T23:59:59.000Z

206

Electron gas grid semiconductor radiation detectors  

DOE Patents (OSTI)

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.

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

2002-01-01T23:59:59.000Z

207

Spin Transport in Semiconductor heterostructures  

SciTech Connect

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.

Domnita Catalina Marinescu

2011-02-22T23:59:59.000Z

208

Photoelectrochemistry of Semiconductor Nanowire Arrays  

DOE Green Energy (OSTI)

This project supported research on the growth and photoelectrochemical characterization of semiconductor nanowire arrays, and on the development of catalytic materials for visible light water splitting to produce hydrogen and oxygen. Silicon nanowires were grown in the pores of anodic aluminum oxide films by the vapor-liquid-solid technique and were characterized electrochemically. Because adventitious doping from the membrane led to high dark currents, silicon nanowire arrays were then grown on silicon substrates. The dependence of the dark current and photovoltage on preparation techniques, wire diameter, and defect density was studied for both p-silicon and p-indium phosphide nanowire arrays. The open circuit photovoltage of liquid junction cells increased with increasing wire diameter, reaching 350 mV for micron-diameter silicon wires. Liquid junction and radial p-n junction solar cells were fabricated from silicon nano- and microwire arrays and tested. Iridium oxide cluster catalysts stabilized by bidentate malonate and succinate ligands were also made and studied for the water oxidation reaction. Highlights of this project included the first papers on silicon and indium phosphide nanowire solar cells, and a new procedure for making ligand-stabilized water oxidation catalysts that can be covalently linked to molecular photosensitizers or electrode surfaces.

Mallouk, Thomas E; Redwing, Joan M

2009-11-10T23:59:59.000Z

209

Optical Nonlinearities and Ultrafast Carrier Dynamics in Semiconductor Quantum Dots  

SciTech Connect

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.

Klimov, V.; McBranch, D.; Schwarz, C.

1998-08-10T23:59:59.000Z

210

Thin film solar cell including a spatially modulated intrinsic layer  

SciTech Connect

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

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

1989-03-28T23:59:59.000Z

211

Glass, Plastic and Semiconductors: Packaging Techniques for Miniature Optoelectric Components  

Science Conference Proceedings (OSTI)

At Lawrence Livermore National Laboratory, they have extensive experience with the design and development of miniature photonic systems which require novel packaging schemes. Over the years they have developed silicon micro-optical benches to serve as a stable platform for precision mounting of optical and electronic components. They have developed glass ball lenses that can be fabricated in-situ on the microbench substrate. They have modified commercially available molded plastic fiber ribbon connectors (MT) and added thin film multilayer semiconductor coatings to create potentially low-cost wavelength combiners and wavelength selective filters. They have fabricated both vertical-cavity and in-plane semiconductor lasers and amplifiers, and have packaged these and other components into several miniature photonics systems. For example, they have combined the silicon optical bench with standard electronic packaging techniques and the custom-made wavelength-selective filters to develop a four-wavelength wavelength-division-multiplexing transmitter module mounted in a standard 120-pin ceramic PGA package that couples light from several vertical-cavity-surface-emitting-laser arrays into one multimode fiber-ribbon array. The coupling loss can be as low as 2dB, and the transmitters can be operated at over 1.25 GHz. While these systems were not designed for biomedical or environmental applications, the concepts and techniques are general and widely applicable.

Pocha, M.D.; Garrett, H.E.; Patel, R.R.; Jones II, L.M.; Larson, M.C.; Emanuel, M.A.; Bond, S.W.; Deri, R.J.; Drayton, R.F.; Peterson, H.E.; Lowry, M.E.

1999-12-20T23:59:59.000Z

212

Band gap enhancement of glancing angle deposited TiO{sub 2} nanowire array  

SciTech Connect

Vertically oriented TiO{sub 2} nanowire (NW) arrays were fabricated by glancing angle deposition technique. Field emission-scanning electron microscopy shows the formation of two different diameters {approx}80 nm and {approx}40 nm TiO{sub 2} NW for 120 and 460 rpm azimuthal rotation of the substrate. The x-ray diffraction and Raman scattering depicted the presence of rutile and anatase phase TiO{sub 2}. The overall Raman scattering intensity decreased with nanowire diameter. The role of phonon confinement in anatase and rutile peaks has been discussed. The red (7.9 cm{sup -1} of anatase E{sub g}) and blue (7.4 cm{sup -1} of rutile E{sub g}, 7.8 cm{sup -1} of rutile A{sub 1g}) shifts of Raman frequencies were observed. UV-vis absorption measurements show the main band absorption at 3.42 eV, 3.48 eV, and {approx}3.51 eV for thin film and NW prepared at 120 and 460 rpm, respectively. Three fold enhance photon absorption and intense light emission were observed for NW assembly. The photoluminescence emission from the NW assembly revealed blue shift in main band transition due to quantum confinement in NW structures.

Chinnamuthu, P.; Mondal, A.; Singh, N. K.; Dhar, J. C. [National Institute of Technology Agartala, Department of Electronics and Communication Engineering, Jirania, Tripura (West) 799055 (India); Chattopadhyay, K. K. [Jadavpur University, Department of Physics, Kolkata 700032 (India); Bhattacharya, Sekhar [SSN Research Centre, Tamil Nadu 603110 (India)

2012-09-01T23:59:59.000Z

213

Bispyridinium-phenylene-based copolymers: low band gap n-type alternating copolymers  

E-Print Network (OSTI)

Bispyridinium-phenylene-based conjugated donor–acceptor copolymers were synthesized by a Stille cross-coupling and cyclization sequence. These polyelectrolytes are freely soluble in organic solvents and display broad optical ...

Swager, Timothy Manning

214

Temperature-dependent energy band gap variation in self-organized InAs quantum dots  

SciTech Connect

We investigated the temperature-dependent variation of the photoluminescence emission energy of self-organized InAs/GaAs quantum dots (QDs) grown by conventional Stranski-Krastanov (SK) molecular beam epitaxy and migration-enhanced molecular beam epitaxy (MEMBE) and that of MEMBE InAs QDs in a symmetric and an asymmetric In{sub 0.2}Ga{sub 0.8}As/GaAs well. The temperature-dependent energy variation of each QD is analyzed in low and high temperature regions, including a sigmoidal behavior of conventional SK quantum dots with the well-known Varshni and semi-empirical Fan models.

Yeo, Inah [CEA/CNRS/UJF Joint Team ''Nanophysics and Semiconductors,'' Institut Neel-CNRS, BP 166, 25 rue des Martyrs, 38042 Grenoble Cedex 9 (France); Dong Song, Jin; Lee, Jungil [Nanophotonics Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of)

2011-10-10T23:59:59.000Z

215

Excitation Dynamics in Low Band Gap Donor-Acceptor Copolymers and Blends  

E-Print Network (OSTI)

Donor-acceptor (D-A) type copolymers show great potential for the application in the active layer of organic solar cells. Nevertheless the nature of the excited states, the coupling mechanism and the relaxation pathways following photoexcitation are yet to be clarified. We carried out comparative measurements of the steady state absorption and photoluminescence (PL) on the copolymer poly[N-(1-octylnonyl)-2,7-carbazole] -alt-5,5-[4',7' -di(thien-2-yl)-2',1',3' -benzothiadiazole] (PCDTBT), its building blocks as well as on the newly synthesized N-(1-octylnonyl)-2,7-bis-[(5-phenyl)thien-2-yl)carbazole (BPT-carbazole) (see Figure 1). The high-energy absorption band (HEB) of PCDTBT was identified with absorption of carbazoles with adjacent thiophene rings while the low-energy band (LEB) originates instead from the charge transfer (CT) state delocalized over the aforementioned unit with adjacent benzothiadiazole group. Photoexcitation of the HEB is followed by internal relaxation prior the radiative decay to the ground state. Adding PC70BM results in the efficient PL quenching within the first 50 ps after excitation. From the PL excitation experiments no evidence for a direct electron transfer from the HEB of PCDTBT towards the fullerene acceptor was found, therefore the internal relaxation mechanisms within PCDTBT can be assumed to precede. Our findings indicate that effective coupling between copolymer building blocks governs the photovoltaic performance of the blends.

Björn Gieseking; Berthold Jäck; Eduard Preis; Stefan Jung; Michael Forster; Ullrich Scherf; Carsten Deibel; Vladimir Dyakonov

2012-06-20T23:59:59.000Z

216

Tunable micro-cavities in photonic band-gap yarns and optical fibers  

E-Print Network (OSTI)

The vision behind this work is the fabrication of high performance innovative fiber-based optical components over kilometer length-scales. The optical properties of these fibers derive from their multilayer dielectric ...

Benoit, Gilles, Ph. D. Massachusetts Institute of Technology

2006-01-01T23:59:59.000Z

217

Observation of Wakefields in a Beam-Driven Photonic Band Gap...  

NLE Websites -- All DOE Office Websites (Extended Search)

Proceedings of IPAC'10, Kyoto, Japan THPD066 03 Linear Colliders, Lepton Accelerators and New Acceleration Techniques A14 Advanced Concepts 4431 Figure 1: Schematic...

218

Fabrication of band-gap structures in planar nonlinear waveguides for second harmonic generation  

Science Conference Proceedings (OSTI)

The work presented here deals with the design and fabrication of the linear grating on a LiNbO3 planar waveguide to obtain an efficient second harmonic generation operating in Cerenkov configuration. The lithium niobate is a nonlinear material ... Keywords: e-beam lithography, nonlinear optics

V. Foglietti; E. Cianci; D. Pezzetta; C. Sibilia; M. Marangoni; R. Osellame; R. Ramponi

2003-06-01T23:59:59.000Z

219

Sandia National Labs: PCNSC: Departments: Semiconductor and Optical  

NLE Websites -- All DOE Office Websites (Extended Search)

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

220

High-power semiconductor separate-confinement double heterostructure lasers  

Science Conference Proceedings (OSTI)

The review is devoted to high-power semiconductor lasers. Historical reference is presented, physical and technological foundations are considered, and the concept of high-power semiconductor lasers is formulated. Fundamental and technological reasons limiting the optical power of a semiconductor laser are determined. The results of investigations of cw and pulsed high-power semiconductor lasers are presented. Main attention is paid to inspection of the results of experimental studies of single high-power semiconductor lasers. The review is mainly based on the data obtained in the laboratory of semiconductor luminescence and injection emitters at the A.F. Ioffe Physicotechnical Institute. (review)

Tarasov, I S [A.F. Ioffe Physical-Technical Institute, Russian Academy of Sciences, St. Petersburg (Russian Federation)

2010-10-15T23:59:59.000Z

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


221

Method for removing semiconductor layers from salt substrates  

DOE Patents (OSTI)

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.

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

1985-08-27T23:59:59.000Z

222

Light sources based on semiconductor current filaments  

DOE Patents (OSTI)

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

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

2003-01-01T23:59:59.000Z

223

Zecon Solar Semiconductor Inc | Open Energy Information  

Open Energy Info (EERE)

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

224

Emissivity Correcting Pyrometry of Semiconductor Growth  

NLE Websites -- All DOE Office Websites (Extended Search)

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

225

Substrate solder barriers for semiconductor epilayer growth  

DOE Patents (OSTI)

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

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

1987-10-23T23:59:59.000Z

226

Semiconductor Equipment and Materials International SEMI | Open Energy  

Open Energy Info (EERE)

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

227

Taiwan Semiconductor Manufacturing Co Ltd TSMC | Open Energy Information  

Open Energy Info (EERE)

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

228

Method Of Transferring A Thin Crystalline Semiconductor Layer  

NLE Websites -- All DOE Office Websites (Extended Search)

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

229

Coherent optical control of electronic excitations in functionalized semiconductor nanostructures  

Science Conference Proceedings (OSTI)

The feasibility of creating and manipulating coherent quantum states on surfaces offunctionalized semiconductor nanostructures is computationally investigated. Quantumdynamics simulations of electron-hole transfer between catechol molecules adsorbed ... Keywords: adsorbates, coherent control, semiconductors, wave-packet dynamics

L. G. C. Rego; S. G. Abuabara; V. S. Batista

2005-07-01T23:59:59.000Z

230

Business Case Slide 27: High-Value: Semiconductors - Basis for...  

NLE Websites -- All DOE Office Websites (Extended Search)

Semiconductors - Basis for Use Basis for use DUO2 has good electronic properties for semi-conductor applications Have made and tested a diode and transistor which appear superior...

231

Business Case Slide 25: High-Value: Semiconductors - Description  

NLE Websites -- All DOE Office Websites (Extended Search)

Semiconductors - Description Receipt of rare DUO crystals at ORNL Receipt of rare DUO2 crystals at ORNL Description Use DUO2 as a semiconductor material Computer CPU or RAM chips...

232

Lattice mismatched compound semiconductors and devices on silicon  

E-Print Network (OSTI)

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

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

2011-01-01T23:59:59.000Z

233

Surface passivation process of compound semiconductor material using UV photosulfidation  

DOE Patents (OSTI)

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.

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

1995-01-01T23:59:59.000Z

234

Metal Oxide Semiconductor Nanoparticles Open the Door to ...  

Using metal oxide semiconductor nanoparticles to target and control biological molecules could fuel medical breakthroughs in many areas, including ...

235

Method of physical vapor deposition of metal oxides on semiconductors  

DOE Patents (OSTI)

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

Norton, David P. (Knoxville, TN)

2001-01-01T23:59:59.000Z

236

Organic conductive films for semiconductor electrodes  

DOE Patents (OSTI)

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

Frank, Arthur J. (Lakewood, CO)

1984-01-01T23:59:59.000Z

237

Electrical Usage Characterization of Semiconductor Processing Tools  

E-Print Network (OSTI)

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 is currently being examined by SEMATECH for future publication. Example data will be presented showing the power, energy, and current load profiles of a typical tool.

Hinson, S. R.

2000-04-01T23:59:59.000Z

238

High resolution scintillation detector with semiconductor readout  

DOE Patents (OSTI)

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

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

2000-01-01T23:59:59.000Z

239

Semiconductor diode with external field modulation  

DOE Patents (OSTI)

A non-destructive-readout nonvolatile semiconductor diode switching device that may be used as a memory element is disclosed. The diode switching device is formed with a ferroelectric material disposed above a rectifying junction to control the conduction characteristics therein by means of a remanent polarization. The invention may be used for the formation of integrated circuit memories for the storage of information.

Nasby, Robert D. (Albuquerque, NM)

2000-01-01T23:59:59.000Z

240

Preparation of III-V semiconductor nanocrystals  

DOE Patents (OSTI)

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

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

1996-01-01T23:59:59.000Z

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


241

Optical temperature sensor using thermochromic semiconductors  

DOE Patents (OSTI)

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

Kronberg, J.W.

1994-01-01T23:59:59.000Z

242

World Wide Web Information Servers  

NLE Websites -- All DOE Office Websites (Extended Search)

World Wide Web Information Servers World Wide Web Information Servers Lawrence Berkeley Laboratory recently announced a gopher and World Wide Web site. To get to the web site, telnet to www.lbl.gov, login: www. Access is provided to LBL's gopher, library catalog, and publication list. The Center is funding the implementation of a WWW network node for on-line access to publications, databases, and documents full of hypermedia links to other documents or information systems from the Energy & Environment Division. Full implementation is expected by May 1994, and will include access to a variety of information from all the research programs and centers. The technology transfer project calls for this newsletter to be published on WWW using the Mosaic interface under development at the National Center

243

A Spintronic Semiconductor with Selectable Charge Carriers  

NLE Websites -- All DOE Office Websites (Extended Search)

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

244

A Spintronic Semiconductor with Selectable Charge Carriers  

NLE Websites -- All DOE Office Websites (Extended Search)

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

245

A Spintronic Semiconductor with Selectable Charge Carriers  

NLE Websites -- All DOE Office Websites (Extended Search)

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

246

A Spintronic Semiconductor with Selectable Charge Carriers  

NLE Websites -- All DOE Office Websites (Extended Search)

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

247

A Spintronic Semiconductor with Selectable Charge Carriers  

NLE Websites -- All DOE Office Websites (Extended Search)

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

248

A Spintronic Semiconductor with Selectable Charge Carriers  

NLE Websites -- All DOE Office Websites (Extended Search)

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

249

Band anticrossing effects in highly mismatched semiconductor alloys  

DOE Green Energy (OSTI)

The first five chapters of this thesis focus on studies of band anticrossing (BAC) effects in highly electronegativity- mismatched semiconductor alloys. The concept of bandgap bowing has been used to describe the deviation of the alloy bandgap from a linear interpolation. Bowing parameters as large as 2.5 eV (for ZnSTe) and close to zero (for AlGaAs and ZnSSe) have been observed experimentally. Recent advances in thin film deposition techniques have allowed the growth of semiconductor alloys composed of significantly different constituents with ever- improving crystalline quality (e.g., GaAs{sub 1-x}N{sub x} and GaP{sub 1-x}N{sub x} with x {approx}< 0.05). These alloys exhibit many novel and interesting properties including, in particular, a giant bandgap bowing (bowing parameters > 14 eV). A band anticrossing model has been developed to explain these properties. The model shows that the predominant bowing mechanism in these systems is driven by the anticrossing interaction between the localized level associated with the minority component and the band states of the host. In this thesis I discuss my studies of the BAC effects in these highly mismatched semiconductors. It will be shown that the results of the physically intuitive BAC model can be derived from the Hamiltonian of the many-impurity Anderson model. The band restructuring caused by the BAC interaction is responsible for a series of experimental observations such as a large bandgap reduction, an enhancement of the electron effective mass, and a decrease in the pressure coefficient of the fundamental gap energy. Results of further experimental investigations of the optical properties of quantum wells based on these materials will be also presented. It will be shown that the BAC interaction occurs not only between localized states and conduction band states at the Brillouin zone center, but also exists over all of k-space. Finally, taking ZnSTe and ZnSeTe as examples, I show that BAC also occurs between localized states and the valence band states. Soft x-ray fluorescence experiments provide direct evidence of the BAC interaction in these systems. In the final chapter of the thesis, I describe and summarize my studies of optical properties of wurtzite InN and related alloys. Early studies performed on InN films grown by sputtering techniques suggested a direct bandgap of {approx}1.9 eV for this semiconductor. Very recently, high-quality InN films with much higher mobility have become available by using the molecular beam epitaxy growth method. Optical experiments carried out on these samples reveal a narrow bandgap for InN of 0.77 eV, much lower than the previously accepted value. Optical properties of InGaN and InAlN ternaries on the In rich side have also been characterized and are found to be consistent with the narrow bandgap of InN. The bandgap bowing parameters in these alloys were determined. In the context of these findings, the bandgap energies of InGaN and InAlN were found to cover a wide spectral range from the infrared for InN to the ultraviolet for GaN and deep ultraviolet for AlN. The significance of this work is rooted in many important applications of nitride semiconductors in optoelectronics and solar energy conversion devices.

Wu, Junqiao

2002-09-09T23:59:59.000Z

250

VENTILATION (HVAC) FAILURE (BUILDING WIDE)  

E-Print Network (OSTI)

VENTILATION (HVAC) FAILURE (BUILDING WIDE) A failure or shutdown of the ventilation system will be signaled by cessation of the audible background "rumbling" sound of the building's HVAC system. As building durations. NOTE: Due to unpredictable pressure differentials in and around the labs during an HVAC failure

Strynadka, Natalie

251

Semiconductor Laser Diode Pumps for Inertial Fusion Energy Lasers  

Science Conference Proceedings (OSTI)

Solid-state lasers have been demonstrated as attractive drivers for inertial confinement fusion on the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) and at the Omega Facility at the Laboratory for Laser Energetics (LLE) in Rochester, NY. For power plant applications, these lasers must be pumped by semiconductor diode lasers to achieve the required laser system efficiency, repetition rate, and lifetime. Inertial fusion energy (IFE) power plants will require approximately 40-to-80 GW of peak pump power, and must operate efficiently and with high system availability for decades. These considerations lead to requirements on the efficiency, price, and production capacity of the semiconductor pump sources. This document provides a brief summary of these requirements, and how they can be met by a natural evolution of the current semiconductor laser industry. The detailed technical requirements described in this document flow down from a laser ampl9ifier design described elsewhere. In brief, laser amplifiers comprising multiple Nd:glass gain slabs are face-pumped by two planar diode arrays, each delivering 30 to 40 MW of peak power at 872 nm during a {approx} 200 {micro}s quasi-CW (QCW) pulse with a repetition rate in the range of 10 to 20 Hz. The baseline design of the diode array employs a 2D mosaic of submodules to facilitate manufacturing. As a baseline, they envision that each submodule is an array of vertically stacked, 1 cm wide, edge-emitting diode bars, an industry standard form factor. These stacks are mounted on a common backplane providing cooling and current drive. Stacks are conductively cooled to the backplane, to minimize both diode package cost and the number of fluid interconnects for improved reliability. While the baseline assessment in this document is based on edge-emitting devices, the amplifier design does not preclude future use of surface emitting diodes, which may offer appreciable future cost reductions and increased reliability. The high-level requirements on the semiconductor lasers involve reliability, price points on a price-per-Watt basis, and a set of technical requirements. The technical requirements for the amplifier design in reference 1 are discussed in detail and are summarized in Table 1. These values are still subject to changes as the overall laser system continues to be optimized. Since pump costs can be a significant fraction of the overall laser system cost, it is important to achieve sufficiently low price points for these components. At this time, the price target for tenth-of-akind IFE plant is $0.007/Watt for packaged devices. At this target level, the pumps account for approximately one third of the laser cost. The pump lasers should last for the life of the power plant, leading to a target component lifetime requirement of roughly 14 Ghosts, corresponding to a 30 year plant life and 15 Hz repetition rate. An attractive path forward involes pump operation at high output power levels, on a Watts-per-bar (Watts/chip) basis. This reduces the cost of pump power (price-per-Watt), since to first order the unit price does not increase with power/bar. The industry has seen a continual improvement in power output, with current 1 cm-wide bars emitting up to 500 W QCW (quasi-continuous wave). Increased power/bar also facilitates achieving high irradiance in the array plane. On the other hand, increased power implies greater heat loads and (possibly) higher current drive, which will require increased attention to thermal management and parasitic series resistance. Diode chips containing multiple p-n junctions and quantum wells (also called nanostack structures) may provide an additional approach to reduce the peak current.

Deri, R J

2011-01-03T23:59:59.000Z

252

Semiconductor Manufacturing International Corp SMIC | Open Energy  

Open Energy Info (EERE)

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

253

Isotopically engineered semiconductors: from the bulk tonanostructures  

SciTech Connect

Research performed with semiconductors with controlled isotopic composition is evolving from the measurement of fundamental properties in the bulk to those measured in superlattices and nanostructures. This is driven in part by interests associated with the fields of 'spintronics' and quantum computing. In this topical review, which is dedicated to Prof. Abstreiter, we introduce the subject by reviewing classic and recent measurements of phonon frequencies, thermal conductivity, bandgap renormalizations, and spin coherence lifetimes in isotopically controlled bulk group IV semiconductors. Next, we review phonon properties measured in isotope heterostructures, including pioneering work made possible by superlattices grown by the group of Prof. Abstreiter. We close the review with an outlook on the exciting future possibilities offered through isotope control in 1, 2, and 3 dimensions that will be possible due to advances in nanoscience.

Ager III, Joel W.; Haller, Eugene E.

2006-04-07T23:59:59.000Z

254

Proximity charge sensing for semiconductor detectors  

SciTech Connect

A non-contact charge sensor includes a semiconductor detector having a first surface and an opposing second surface. The detector includes a high resistivity electrode layer on the first surface and a low resistivity electrode on the high resistivity electrode layer. A portion of the low resistivity first surface electrode is deleted to expose the high resistivity electrode layer in a portion of the area. A low resistivity electrode layer is disposed on the second surface of the semiconductor detector. A voltage applied between the first surface low resistivity electrode and the second surface low resistivity electrode causes a free charge to drift toward the first or second surface according to a polarity of the free charge and the voltage. A charge sensitive preamplifier coupled to a non-contact electrode disposed at a distance from the exposed high resistivity electrode layer outputs a signal in response to movement of free charge within the detector.

Luke, Paul N; Tindall, Craig S; Amman, Mark

2013-10-08T23:59:59.000Z

255

Semiconductor P-I-N detector  

DOE Patents (OSTI)

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

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

2001-01-01T23:59:59.000Z

256

Semiconductor junction formation by directed heat  

DOE Patents (OSTI)

The process of the invention includes applying precursors 6 with N- and P-type dopants therein to a silicon web 2, with the web 2 then being baked in an oven 10 to drive off excessive solvents, and the web 2 is then heated using a pulsed high intensity light in a mechanism 12 at 1100.degree.-1150.degree. C. for about 10 seconds to simultaneously form semiconductor junctions in both faces of the web.

Campbell, Robert B. (Pittsburgh, PA)

1988-03-24T23:59:59.000Z

257

GaTe semiconductor for radiation detection  

SciTech Connect

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

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

2009-06-23T23:59:59.000Z

258

Fuzzy Logic Connectivity in Semiconductor Defect Clustering  

Science Conference Proceedings (OSTI)

In joining defects on semiconductor wafer maps into clusters, it is common for defects caused by different sources to overlap. Simple morphological image processing tends to either join too many unrelated defects together or not enough together. Expert semiconductor fabrication engineers have demonstrated that they can easily group clusters of defects from a common manufacturing problem source into a single signature. Capturing this thought process is ideally suited for fuzzy logic. A system of rules was developed to join disconnected clusters based on properties such as elongation, orientation, and distance. The clusters are evaluated on a pair-wise basis using the fuzzy rules and are joined or not joined based on a defuzzification and threshold. The system continuously re-evaluates the clusters under consideration as their fuzzy memberships change with each joining action. The fuzzy membership functions for each pair-wise feature, the techniques used to measure the features, and methods for improving the speed of the system are all developed. Examples of the process are shown using real-world semiconductor wafer maps obtained from chip manufacturers. The algorithm is utilized in the Spatial Signature Analyzer (SSA) software, a joint development project between Oak Ridge National Lab (ORNL) and SEMATECH.

Gleason, S.S.; Kamowski, T.P.; Tobin, K.W.

1999-01-24T23:59:59.000Z

259

Visible-wavelength semiconductor lasers and arrays  

DOE Patents (OSTI)

A visible semiconductor laser. The visible semiconductor laser includes an InAlGaP active region surrounded by one or more AlGaAs layers on each side, with carbon as the sole p-type dopant. Embodiments of the invention are provided as vertical-cavity surface-emitting lasers (VCSELs) and as edge-emitting lasers (EELs). One or more transition layers comprised of a substantially indium-free semiconductor alloy such as AlAsP, AlGaAsP, or the like may be provided between the InAlGaP active region and the AlGaAS DBR mirrors or confinement layers to improve carrier injection and device efficiency by reducing any band offsets. Visible VCSEL devices fabricated according to the invention with a one-wavelength-thick (1.lambda.) optical cavity operate continuous-wave (cw) with lasing output powers up to 8 mW, and a peak power conversion efficiency of up to 11%.

Schneider, Jr., Richard P. (Albuquerque, NM); Crawford, Mary H. (Albuquerque, NM)

1996-01-01T23:59:59.000Z

260

Semiconductor and Materials Company Inc SAMCO | Open Energy Information  

Open Energy Info (EERE)

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

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


261

Climate VISION: Private Sector Initiatives: Semiconductors: Resources and  

Office of Scientific and Technical Information (OSTI)

Semiconductor Industry Association (SIA) The Semiconductor Industry Association (SIA) is the premier trade association representing the U.S. semiconductor industry. Founded in 1977 by five microelectronics innovators, the SIA has grown to include over 100 companies that account for more than 83% of U.S.-based semiconductor production. The SIA provides a forum for domestic semiconductor companies to work collectively to advance the competitiveness of the $70 billion U.S. chip industry. Through its national and international network of chief executive officers and working committees, the SIA shapes public policy on issues important to the industry and provides a spectrum of services to help its members grow their businesses. World Semiconductor Council (WSC)

262

Graded core/shell semiconductor nanorods and nanorod barcodes  

DOE Patents (OSTI)

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.

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

2010-12-14T23:59:59.000Z

263

Graded core/shell semiconductor nanorods and nanorod barcodes  

DOE Patents (OSTI)

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.

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

2013-03-26T23:59:59.000Z

264

Guiding effect of quantum wells in semiconductor lasers  

Science Conference Proceedings (OSTI)

The guiding effect of InGaAs quantum wells in GaAs- and InP-based semiconductor lasers has been studied theoretically and experimentally. The results demonstrate that such waveguides can be effectively used in laser structures with a large refractive index difference between the quantum well material and semiconductor matrix and a large number of quantum wells (e.g. in InP-based structures). (semiconductor lasers. physics and technology)

Aleshkin, V Ya; Dikareva, Natalia V; Dubinov, A A; Zvonkov, B N; Karzanova, Maria V; Kudryavtsev, K E; Nekorkin, S M; Yablonskii, A N

2013-05-31T23:59:59.000Z

265

 

NLE Websites -- All DOE Office Websites (Extended Search)

CdZnTe room temperature gamma-ray detectors CdZnTe room temperature gamma-ray detectors Paul Luke Lawrence Berkeley National Laboratory Abstract: Ge detectors provide excellent energy resolution and are routinely used in many gamma-ray spectroscopy applications. However, they require cryogenic (LN) cooling due to the small band-gap of Ge. Because of that, substantial effort has been expended in the past several decades on the search and development of wide-band-gap high-Z semiconductors as room-temperature replacement of Ge detectors. CdZnTe emerged as the most promising material to date. A fortuitous combination of the charge transport properties of this material and the coplanar-grid charge sensing technique permits the production of reasonably large detectors with good energy resolution, and the possibility of achieving performance rivaling that of Ge detectors has

266

Climate VISION: Private Sector Initiatives: Semiconductors: Resources and  

Office of Scientific and Technical Information (OSTI)

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

267

July 28, 2010, Guiding semiconductor research through collaborative engagement  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

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

268

Understanding How Semiconductors Absorb Light | U.S. DOE Office...  

Office of Science (SC) Website

Understanding How Semiconductors Absorb Light Basic Energy Sciences (BES) BES Home About Research Facilities Science Highlights Benefits of BES Funding Opportunities Basic Energy...

269

Resonator for Coherent Addition of Semiconductor Laser Arrays ...  

Resonator for Coherent Addition of Semiconductor Laser Arrays and Applications for a Solar Pumped Laser Array Oak Ridge National Laboratory. Contact ...

270

Metal Oxide Semiconductor Nanoparticles Pave the Way for ...  

Argonne researchers have developed a unique application of technology that involves using metal oxide semiconductor nanoparticles to target and control biological ...

271

Method for depositing high-quality microcrystalline semiconductor materials  

SciTech Connect

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

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

2011-03-08T23:59:59.000Z

272

Production of 35S for a Liquid Semiconductor Betavoltaic  

DOE Green Energy (OSTI)

The specific energy density from radioactive decay is five to six orders of magnitude greater than the specific energy density in conventional chemical battery and fuel cell technologies. We are currently investigating the use of liquid semiconductor based betavoltaics as a way to directly convert the energy of radioactive decay into electrical power and potentially avoid the radiation damage that occurs in solid state semiconductor devices due to non-ionizing energy loss. Sulfur-35 was selected as the isotope for the liquid semiconductor demonstrations because it can be produced in high specific activity and it is chemically compatible with known liquid semiconductor media.

Meier, David E.; Garnov, A. Y.; Robertson, J. D.; Kwon, J. W.; Wacharasindhu, T.

2009-10-01T23:59:59.000Z

273

Argonne CNM News: HMapping Deformation in Buried Semiconductor...  

NLE Websites -- All DOE Office Websites (Extended Search)

CMOS performance. Nano-XRD allows for the first time in situ nanoscale mapping of lattice strain and tilt within a buried semiconductor layer at high spatial resolution...

274

Photophysics of Two-dimensional Semiconductor Nanoparticle/Liquid Interfaces  

Science Conference Proceedings (OSTI)

These studies have investigated the optical properties of two very different types of two-dimensional semiconductor nanoclusters and superlattices of these nanoclusters.

Kelley, David F.

2003-11-14T23:59:59.000Z

275

Gallium-Nitride Transistors for High-Efficiency Industrial Power Supplies, Phase 1: State of Semiconductor Development and Industrial Power Supply Market  

Science Conference Proceedings (OSTI)

This white paper describes recent advancements in the development of Gallium-Nitride (GaN) transistors for power conversion applications. This wide bandgap semiconductor has the potential to reduce losses and improve performance of power converters. The industrial power supply market is described and the application of GaN to power conversion in this segment is introduced for future work.

2013-12-23T23:59:59.000Z

276

III-Nitride Semiconductors for Photovoltaic Applications  

DOE Green Energy (OSTI)

Using a band-structure method that includes bandgap correction, we study the chemical trends of the bandgap variation in III-V semiconductors and predict that the bandgap for InN is 0.85 0.1 eV. This result suggests that InN and its III-nitride alloys are suitable for photovoltaic applications. The unusually small bandgap for InN is explained in terms of the atomic energies and the bandgap deformation potentials. The electronic and structural properties of the nitrides and their alloys are also provided.

Wei, S. H.

2003-05-01T23:59:59.000Z

277

GaAs photoconductive semiconductor switch  

DOE Patents (OSTI)

A high gain, optically triggered, photoconductive semiconductor switch (PCSS) implemented in GaAs as a reverse-biased pin structure with a passivation layer above the intrinsic GaAs substrate in the gap between the two electrodes of the device. The reverse-biased configuration in combination with the addition of the passivation layer greatly reduces surface current leakage that has been a problem for prior PCSS devices and enables employment of the much less expensive and more reliable DC charging systems instead of the pulsed charging systems that needed to be used with prior PCSS devices.

Loubriel, Guillermo M. (Sandia Park, NM); Baca, Albert G. (Albuquerque, NM); Zutavern, Fred J. (Albuquerque, NM)

1998-01-01T23:59:59.000Z

278

Photocatalytic semiconductor clusters for fuel production  

DOE Green Energy (OSTI)

High quality crystalline, monodisperse nanometer-size semiconductor clusters were successfully grown using an inverse micellar synthesis process and their optical and structural properties were studied. Among the materials studied were PbS, FeS{sub 2}, MoS{sub 2}, CdS and related compounds. The results demonstrated strong electronic quantum confinement effects and broad tailorability of the bandgaps with decreasing cluster size, features that are important for the potential use of these materials as photocatalysts for solar fuel production and solar detoxification. The highlights of the work are included in an Executive Summary.

Wilcoxon, J.P.; Bliss, D.E.; Martin, J.E. [and others

1995-10-01T23:59:59.000Z

279

Fully Integrated Complementary Metal Oxide Semiconductor (CMOS) Bio-Assay Platform  

E-Print Network (OSTI)

Oxide Semiconductor (CMOS) Bio-Assay Platform by OctavianOxide Semiconductor (CMOS) Bio-Assay Platform by OctavianOxide Semiconductor (CMOS) Bio-Assay Platform by Octavian

Florescu, Octavian

2010-01-01T23:59:59.000Z

280

Distributed Quantum Computation Architecture Using Semiconductor Nanophotonics  

E-Print Network (OSTI)

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

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

2009-06-15T23:59:59.000Z

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


281

Visible-wavelength semiconductor lasers and arrays  

DOE Patents (OSTI)

The visible semiconductor laser includes an InAlGaP active region surrounded by one or more AlGaAs layers on each side, with carbon as the sole p-type dopant. Embodiments of the invention are provided as vertical-cavity surface-emitting lasers (VCSELs) and as edge-emitting lasers (EELs). One or more transition layers comprised of a substantially indium-free semiconductor alloy such as AlAsP, AlGaAsP, or the like may be provided between the InAlGaP active region and the AlGaAS DBR mirrors or confinement layers to improve carrier injection and device efficiency by reducing any band offsets. Visible VCSEL devices fabricated according to the invention with a one-wavelength-thick (1{lambda}) optical cavity operate continuous-wave (cw) with lasing output powers up to 8 mW, and a peak power conversion efficiency of up to 11%. 5 figs.

Schneider, R.P. Jr.; Crawford, M.H.

1996-09-17T23:59:59.000Z

282

Coated semiconductor devices for neutron detection  

DOE Green Energy (OSTI)

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

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

2002-01-01T23:59:59.000Z

283

Photonic switching devices based on semiconductor nanostructures  

E-Print Network (OSTI)

Squeezing and guiding light into semiconductor nanostructures delivers revolutionary concepts of photonic devices, which may offer a practical pathway towards power-efficient optical networks. In this review, we consider photonic switches using semiconductor quantum dots (QDs) and photonic cavities. By intuitively introducing in a field enhancement factor, the optical nonlinearity of nano-photonic switches can be understood and this has shown their unique features to dramatically improve the power-density/speed limitation that has lain in conventional photonic switches for decades. In addition, the power consumption has been reduced due to the atom-like characterization of QDs as well as the nano-size footprint of photonic cavities. Based on this theoretical perspective, the current progress of QD/cavity switches is reviewed in terms of various optical nonlinearities which have been employed to demonstrate photonic switching at the nanoscale. Emerging functionalities enabled by cavity nonlinear effects such as the wavelength tuning and Purcell-factor tuning have been further introduced.

Chao-Yuan Jin; Osamu Wada

2013-08-11T23:59:59.000Z

284

Dilute magnetic semiconductors in spin-polarized electronics (invited)  

SciTech Connect

Dilute magnetic semiconductors have proven to be very useful in building an all-semiconductor platform for spintronics{emdash}so far they provide the only viable route to establish spin-polarized current injection into a nonmagnetic semiconductor. The reasons for this become apparent from a simple spin-channel model, which predicts that spin injection into a semiconductor can, within linear response, only readily be achieved from a ferromagnetic injector that has: (i) a resistivity that is comparable to the semiconductor and (ii) preferably is 100% spin polarized. Both of these criteria can be met in magnetic semiconductors, but (so far) are hard to achieve using other materials. Experimentally, we demonstrate how dilute magnetic II{endash}VI semiconductors can be used to inject a strongly (up to 90%) spin-polarized current into a light emitting diode. In addition, we discuss the implications of the spin-channel model for the observation of giant magnetoresistance-like effects in the magnetoresistance of an all-semiconductor device. {copyright} 2001 American Institute of Physics.

Schmidt, Georg; Molenkamp, Laurens W.

2001-06-01T23:59:59.000Z

285

Semiconductor device design using the BiMADS algorithm  

Science Conference Proceedings (OSTI)

Designing high-performance semiconductor devices is a complex optimization problem, which is characterized by multiple and, often, conflicting objectives. In this research work, we introduce a multi-objective optimization design approach based on the ... Keywords: Diodes, Drift-diffusion, Energy-transport, MESFETs, MOSFETs, Optimization, Semiconductors

Giovanni Stracquadanio, Vittorio Romano, Giuseppe Nicosia

2013-06-01T23:59:59.000Z

286

Study on Water-Cooled Solar Semiconductor Air Conditioner  

Science Conference Proceedings (OSTI)

Water-cooled solar semiconductor air conditioner was designed. Relevant calculation was made to determine the room's cooling load, which export the solar panels and battery capacity, followed by selection of CNC matcher. Development work also involves ... Keywords: solar energy, peltier effect, semiconductor air conditioner

Dong Zhi-Ming; Chang Ji-Bin; Xiang Li-Juan; Zhou Xue-Bin

2012-04-01T23:59:59.000Z

287

Interesting Electronic and Dynamic Properties of Quantum Dot Quantum Wells and other Semiconductor Nanocrystal Heterostructures .  

E-Print Network (OSTI)

??Some interesting electronic and dynamic properties of semiconductor nanocrystal heterostructures have been investigated using various spectroscopic methods. Semiconductor nanocrystal heterostructures were prepared using colloidal synthesis… (more)

Schill, Alexander Wilhem

2006-01-01T23:59:59.000Z

288

High-Throughput Transfer Imprinting for Organic Semiconductors  

E-Print Network (OSTI)

Development of nanoimprint lithography(NIL) has enabled high-throughput and high-resolution patterning over the optical limitation. In recent years, thermal nanoimprint has been used to directly pattern functional materials such as organic 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. 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 nanoimprint scheme to enable residual-layer-free patterning of organic semiconductors without mold contamination. The transfer imprinting technique is amenable to roll-to-roll process for high-throughput patterning of organic semiconductors for low-cost organic electronic applications.

Choo, Gihoon

2013-08-01T23:59:59.000Z

289

Microbially Mediated Method for Making Semiconductor Nanoparticles  

or quantum dot nanoparticles, are increasingly used in a wide range of electronics, including LED displays, solar cells, and medical imaging.

290

News Item  

NLE Websites -- All DOE Office Websites (Extended Search)

October 1, 2013 October 1, 2013 Time: 11:00 am Speaker: Mikhail Zamkov, Bowling Green State University Title: Engineering of Semiconductor Nanocrystals & Nanocrystal Solids for Renewable Energy Applications Location: 67-3111 Chemla room Hosted by Delia Milliron: I will discuss a novel methodology for depositing colloidal semiconductor nanocrystals into all-inorganic solid films with implications both to nanocrystal solar cells and nanocrystal light-emitting devices. The reported strategy utilizes a simple scheme for incorporating PbS or CdSe semiconductor nanocrystals into matrices of a wide-band gap CdS semiconductor for stable and efficient operation of solution-processed devices. The two key benefits of this approach include: (i) all-inorganic architecture promoting superior thermal and chemical stability, and - (ii)

291

Hybrid Semiconductors for Hardier Electronics and Optoelectronics? |  

NLE Websites -- All DOE Office Websites (Extended Search)

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

292

Internal cooling in a semiconductor laser diode  

E-Print Network (OSTI)

Abstract—A thermal model of a diode laser structure is developed which includes a bipolar thermoelectric term not included in previous models. It is shown that heterostructure band offsets can be chosen so that there are thermoelectric cooling sources near the active region; this method of cooling is internal to the device itself, as opposed to temperature stabilization schemes which employ an external cooler. A novel laser structure is proposed that is capable of internal cooling in the Ga1 In As Sb1 –GaSb material system with = 2 64 m. Index Terms—Electrothermal effects, lasers, laser thermal factors, photothermal effects, semiconductor lasers, thermionic emission, thermionic energy conversion, thermoelectric devices, thermoelectric energy conversion, thermoelectricity. Fig. 1. Band structure and thermoelectric heat source distribution for (a) and (b) conventional SCH, and (c) and (d) ICICLE.

K. P. Pipe; R. J. Ram; A. Shakouri

1995-01-01T23:59:59.000Z

293

Exciton binding energy in semiconductor quantum dots  

Science Conference Proceedings (OSTI)

In the adiabatic approximation in the context of the modified effective mass approach, in which the reduced exciton effective mass {mu} = {mu}(a) is a function of the radius a of the semiconductor quantum dot, an expression for the exciton binding energy E{sub ex}(a) in the quantum dot is derived. It is found that, in the CdSe and CdS quantum dots with the radii a comparable to the Bohr exciton radii a{sub ex}, the exciton binding energy E{sub ex}(a) is substantially (respectively, 7.4 and 4.5 times) higher than the exciton binding energy in the CdSe and CdS single crystals.

Pokutnii, S. I., E-mail: Pokutnyi_Sergey@inbox.ru [National Academy of Sciences of Ukraine, G.V. Kurdjumov Institute for Metal Physics (Ukraine)

2010-04-15T23:59:59.000Z

294

Ion Trap in a Semiconductor Chip  

E-Print Network (OSTI)

The electromagnetic manipulation of isolated atoms has led to many advances in physics, from laser cooling and Bose-Einstein condensation of cold gases to the precise quantum control of individual atomic ion. Work on miniaturizing electromagnetic traps to the micrometer scale promises even higher levels of control and reliability. Compared with 'chip traps' for confining neutral atoms, ion traps with similar dimensions and power dissipation offer much higher confinement forces and allow unparalleled control at the single-atom level. Moreover, ion microtraps are of great interest in the development of miniature mass spectrometer arrays, compact atomic clocks, and most notably, large scale quantum information processors. Here we report the operation of a micrometer-scale ion trap, fabricated on a monolithic chip using semiconductor micro-electromechanical systems (MEMS) technology. We confine, laser cool, and measure heating of a single 111Cd+ ion in an integrated radiofrequency trap etched from a doped gallium arsenide (GaAs) heterostructure.

D. Stick; W. K. Hensinger; S. Olmschenk; M. J. Madsen; K. Schwab; C. Monroe

2006-01-09T23:59:59.000Z

295

Ultra wide-bandwidth micro energy harvester  

E-Print Network (OSTI)

An ultra wide-bandwidth resonating thin film PZT MEMS energy harvester has been designed, modeled, fabricated and tested. It harvests energy from parasitic ambient vibration at a wide range of amplitude and frequency via ...

Hajati, Arman

2011-01-01T23:59:59.000Z

296

Spin Splitting and Spin Current in Strained Bulk Semiconductors  

SciTech Connect

We present a theory for two recent experiments in bulk strained semiconductors and show that a new, previously overlooked, strain spin-orbit coupling term may play a fundamental role. We propose simple experiments that could clarify the origin of strain-induced spin-orbit coupling terms in inversion asymmetric semiconductors. We predict that a uniform magnetization parallel to the electric field will be induced in the samples studied in for specific directions of the applied electric field. We also propose special geometries to detect spin currents in strained semiconductors.

Bernevig, B.Andrei; Zhang, Shou-Cheng; /Stanford U., Phys. Dept.

2010-01-15T23:59:59.000Z

297

Synthesis and Manipulation of Semiconductor Nanocrystals inMicrofluidic Reactors  

SciTech Connect

Microfluidic reactors are investigated as a mechanism tocontrol the growth of semiconductor nanocrystals and characterize thestructural evolution of colloidal quantum dots. Due to their shortdiffusion lengths, low thermal masses, and predictable fluid dynamics,microfluidic devices can be used to quickly and reproducibly alterreaction conditions such as concentration, temperature, and reactiontime, while allowing for rapid reagent mixing and productcharacterization. These features are particularly useful for colloidalnanocrystal reactions, which scale poorly and are difficult to controland characterize in bulk fluids. To demonstrate the capabilities ofnanoparticle microreactors, a size series of spherical CdSe nanocrystalswas synthesized at high temperature in a continuous-flow, microfabricatedglass reactor. Nanocrystal diameters are reproducibly controlled bysystematically altering reaction parameters such as the temperature,concentration, and reaction time. Microreactors with finer control overtemperature and reagent mixing were designed to synthesize nanoparticlesof different shapes, such as rods, tetrapods, and hollow shells. The twomajor challenges observed with continuous flow reactors are thedeposition of particles on channel walls and the broad distribution ofresidence times that result from laminar flow. To alleviate theseproblems, I designed and fabricated liquid-liquid segmented flowmicroreactors in which the reaction precursors are encapsulated inflowing droplets suspended in an immiscible carrier fluid. The synthesisof CdSe nanocrystals in such microreactors exhibited reduced depositionand residence time distributions while enabling the rapid screening aseries of samples isolated in nL droplets. Microfluidic reactors werealso designed to modify the composition of existing nanocrystals andcharacterize the kinetics of such reactions. The millisecond kinetics ofthe CdSe-to-Ag2Se nanocrystal cation exchange reaction are measured insitu with micro-X-ray Absorption Spectroscopy in silicon microreactorsspecifically designed for rapid mixing and time-resolved X-rayspectroscopy. These results demonstrate that microreactors are valuablefor controlling and characterizing a wide range of reactions in nLvolumes even when nanoscale particles, high temperatures, causticreagents, and rapid time scales are involved. These experiments providethe foundation for future microfluidic investigations into the mechanismsof nanocrystal growth, crystal phase evolution, and heterostructureassembly.

Chan, Emory Ming-Yue

2006-12-19T23:59:59.000Z

298

Band-Structure, Optical Properties, and Defect Physics of the Photovoltaic Semiconductor SnS  

Science Conference Proceedings (OSTI)

SnS is a potential earth-abundant photovoltaic (PV) material. Employing both theory and experiment to assess the PV relevant properties of SnS, we clarify on whether SnS has an indirect or direct band gap and what is the minority carrier effective mass as a function of the film orientation. SnS has a 1.07 eV indirect band gap with an effective absorption onset located 0.4 eV higher. The effective mass of minority carrier ranges from 0.5 m{sub 0} perpendicular to the van der Waals layers to 0.2 m{sub 0} into the van der Waals layers. The positive characteristics of SnS feature a desirable p-type carrier concentration due to the easy formation of acceptor-like intrinsic Sn vacancy defects. Potentially detrimental deep levels due to SnS antisite or S vacancy defects can be suppressed by suitable adjustment of the growth condition towards S-rich.

Vidal, J.; Lany, S.; d'Avezac, M.; Zunger, A.; Zakutayev, A.; Francis, J.; Tate, J.

2012-01-16T23:59:59.000Z

299

Varian Semiconductor Equipment Associates Inc VSEA | Open Energy  

Open Energy Info (EERE)

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

300

Ramgraber Semiconductor Equipment GmbH | Open Energy Information  

Open Energy Info (EERE)

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

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


301

Argonne licenses diamond semiconductor discoveries to AKHAN Technologies |  

NLE Websites -- All DOE Office Websites (Extended Search)

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

302

Exploring and enhancing conductivity in semiconductor nanoparticle films  

E-Print Network (OSTI)

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 ...

Porter, Venda Jane

2007-01-01T23:59:59.000Z

303

Semiconductor nanocrystals : synthesis, mechanisms of formation, and applications in biology  

E-Print Network (OSTI)

The primary focus of this thesis is the synthesis and applications of semiconductor nanocrystals, or quantum dots (QDs). Novel synthetic routes to ternary 1-III-VI QDs are presented, and we report the first highly luminescent ...

Allen, Peter M. (Peter Matthew)

2010-01-01T23:59:59.000Z

304

AlGaN/GaN-based power semiconductor switches  

E-Print Network (OSTI)

AlGaN/GaN-based high-electron-mobility transistors (HEMTs) have great potential for their use as high efficiency and high speed power semiconductor switches, thanks to their high breakdown electric field, mobility and ...

Lu, Bin, Ph. D. Massachusetts Institute of Technology

2013-01-01T23:59:59.000Z

305

Spin polarized transport effects in III-V semiconductor heterostructures  

Science Conference Proceedings (OSTI)

In the field of spintronics, GaMnAs, a ferromagnetic semiconductor, offers many advantages to study tunnel magnetotransport properties when used as an electrode. The complexity of the transport mechanisms associated with spin orbit coupled states make ...

J.-M. George

2005-07-01T23:59:59.000Z

306

Printable semiconductor structures and related methods of making and assembling  

DOE Patents (OSTI)

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

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

2011-10-18T23:59:59.000Z

307

Printable semiconductor structures and related methods of making and assembling  

DOE Patents (OSTI)

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

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

2010-09-21T23:59:59.000Z

308

Printable semiconductor structures and related methods of making and assembling  

DOE Patents (OSTI)

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

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

2013-03-12T23:59:59.000Z

309

Colloidal crystal formation in a semiconductor quantum plasma  

Science Conference Proceedings (OSTI)

The static shielding and the far-field dynamical oscillatory wake potentials in an ion-implanted piezoelectric semiconductor with colloid ions as test particles have been investigated in detail. The dielectric response function of the semiconductor is contributed by the quantum effect of electrons through the Bohm potential and lattice electron-phonon coupling effects. It is found that the quantum effect causes tighter binding of the electrons reducing the quantum Debye shielding length and the effective length of the wake potential to several angstroms. Hence, a quasiquantum lattice of colloid ions can be formed in the semiconductor in the quantum scales giving rise to drastic modifications of the ion-implanted semiconductor properties.

Zeba, I.; Uzma, Ch.; Jamil, M.; Salimullah, M. [Department of Physics, GC University, 54000 Lahore (Pakistan); Shukla, P. K. [Theoretische Physik IV, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany)

2010-03-15T23:59:59.000Z

310

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

E-Print Network (OSTI)

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

Silber, Jacob B. (Jacob Bradley)

2006-01-01T23:59:59.000Z

311

Business Case Slide 26: High-Value: Semiconductors - Description...  

NLE Websites -- All DOE Office Websites (Extended Search)

(cont.) Previous Slide Next Slide Table of Contents High-Value: Semiconductors - Description (cont.) Measuring the photo-voltaic properties of a DUO2 diode at NREL Measuring the...

312

A New Earth-Abundant Semiconductor for Solar Energy Conversion  

Science Conference Proceedings (OSTI)

Presentation Title, G2, ZnSnN2: A New Earth-Abundant Semiconductor for Solar Energy Conversion. Author(s), Lise Lahourcade, Naomi C Coronel, Harry A ...

313

Ultrafast nonlinear optical properties of passive and active semiconductor devices  

E-Print Network (OSTI)

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

Motamedi, Ali Reza

2011-01-01T23:59:59.000Z

314

Conductive layer for biaxially oriented semiconductor film growth  

DOE Patents (OSTI)

A conductive layer for biaxially oriented semiconductor film growth and a thin film semiconductor structure such as, for example, a photodetector, a photovoltaic cell, or a light emitting diode (LED) that includes a crystallographically oriented semiconducting film disposed on the conductive layer. The thin film semiconductor structure includes: a substrate; a first electrode deposited on the substrate; and a semiconducting layer epitaxially deposited on the first electrode. The first electrode includes a template layer deposited on the substrate and a buffer layer epitaxially deposited on the template layer. The template layer includes a first metal nitride that is electrically conductive and has a rock salt crystal structure, and the buffer layer includes a second metal nitride that is electrically conductive. The semiconducting layer is epitaxially deposited on the buffer layer. A method of making such a thin film semiconductor structure is also described.

Findikoglu, Alp T. (Los Alamos, NM); Matias, Vladimir (Santa Fe, NM)

2007-10-30T23:59:59.000Z

315

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

DOE Patents (OSTI)

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.

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

2001-01-01T23:59:59.000Z

316

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

DOE Patents (OSTI)

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.

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

2001-01-01T23:59:59.000Z

317

Gas fixation solar cell using gas diffusion semiconductor electrode  

SciTech Connect

A gas diffusion semiconductor electrode and solar cell and a process for gaseous fixation, such as nitrogen photoreduction, CO/sub 2/ photoreduction and fuel gas photo-oxidation are described. The gas diffusion photosensitive electrode has a central electrolyte porous matrix with an activated semiconductor material on one side adapted to be in contact with an electrolyte and a hydrophobic gas diffusion region on the opposite side adapted to be in contact with a supply of molecular gas.

Ang, P.G.; Sammells, A.F.

1980-12-23T23:59:59.000Z

318

Electroluminescence in ion gel gated organic polymer semiconductor transistors  

E-Print Network (OSTI)

emission in ion gel gated, thin film organic semiconductor tran- sistors and investigates the light emission mechanism behind these devices. We report that ion gel gated organic polymer semiconductor transistors emit light when the drain source volt- age... the organic light emitting devices become mainstream, there are several challenges that need to be resolved and current research focus is to ad- dress those challenges. One particular challenge is relatively high operating volt- ages of light emitting organic...

Bhat, Shrivalli

2011-07-12T23:59:59.000Z

319

Thermally robust semiconductor optical amplifiers and laser diodes  

DOE Patents (OSTI)

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

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

2002-01-01T23:59:59.000Z

320

Enterprise-Wide Agreements | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Enterprise-Wide Enterprise-Wide Agreements Enterprise-Wide Agreements DOE's Office of the Chief Information Officer (OCIO) has designed the IT Acquisition: Enterprise-Wide Agreement (EWA) Program to develop and implement policies and procedures that support the identification, acquisition, oversight and compliance of enterprise licenses. EWAs are Department-wide acquisitions of widely used commercial software. The EWA Program has two core objectives to achieve the Program mission : Maximizing IT buying power and reducing total cost of ownership; Streamlining the IT total acquisition lifecycle. The EWA Program applies a centralized, cross-functional, strategic enterprise software solutions approach. The EWA Program leverages opportunities to create efficiencies and enhances the value of IT

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


321

Electron transfer at sensitized semiconductor electrodes  

DOE Green Energy (OSTI)

Electron transfer from the excited state of sensitizing dyes to the conduction band of semiconductors has been studied through photoelectrochemical techniques. Two systems were analyzed in detail: rhodamine B on ZnO and rose bengal on TiO/sub 2/. Prior to electrochemical experimentation, the adsorption characteristics of these dyes were investigated using ZnO, ZnS, and TiO/sub 2/ single crystals as substrates. Absorbance measurements of the adsorbed dye were taken as a function of the solution concentration of the dye. Adsorption isotherms heats of adsorption were also established; they were similar to literature data reported for adsorption of these dyes on powdered substrates. Using the absorbance data, the quantum efficiency for photoinjection of electrons from rhodamine B into a ZnO electrode was determined to be 2.7 x 10/sup -2/. This value was independent of the dye surface concentration down to 50% coverage of the electrode. With the assumption that not all of the rhodamine B adsorbed on the electrode has the same rate of electron injection, a kinetic model for the time decay of the photocurrent was developed; data were analyzed according to this theory. A rate constant for photoreduction of the adsorbed dye was determined for the reducing agents. 86 references.

Spitler, M.T.

1977-03-01T23:59:59.000Z

322

Interconnection-Wide Transmission Planning Initiative: Topic...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

State Agency Input Regarding Electric Resource and Transmission Planning in the Texas Interconnection Interconnection-Wide Transmission Planning Initiative: Topic B, State Agency...

323

Interconnection-Wide Transmission Planning Initiative: Topic...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Interconnection-Wide Transmission Planning Initiative: Topic B, State Agency Input Regarding Electric Resource and Transmission Planning in the Texas Interconnection...

324

WIDE BAND REGENERATIVE FREQUENCY DIVIDER AND MULTIPLIER  

DOE Patents (OSTI)

A regenerative frequency divider and multiplier having wide band input characteristics is presented. The circuit produces output oscillations having frequencies related by a fixed ratio to input oscillations over a wide band of frequencies. In accomplishing this end, the divider-multiplier includes a wide band input circuit coupled by mixer means to a wide band output circuit having a pass band related by a fixed ratio to that of the input circuit. A regenerative feedback circuit derives a fixed frequency ratio feedback signal from the output circuit and applies same to the mixer means in proper phase relation to sustain fixed frequency ratio oscillations in the output circuit.

Laine, E.F.

1959-11-17T23:59:59.000Z

325

HY RID WIDE RANGE TRANSIMPEDAN E AMPLIFIER  

TRANSIMPEDAN E AMPLIFIER TE HNOLOGY SUMMARY Many applications require wide range detection, where detector current is converted to a voltage by a

326

Wide Electrochemical Window Solvents - Energy Innovation Portal  

Biomass and Biofuels; ... This solvent has such a wide electrochemical window and such powerful solvating properties that it is an excellent target solvent ...

327

Contents i ORNL/PPA-2006/1  

E-Print Network (OSTI)

..................................................................... 64 Direct Band Gap Semiconductors on Silicon for Solid State Lighting: Silicon-Based, Blue-Light...................................................... 159 Nano/Micro Systems for Advanced Neutonal Interfacing............................................................................... 182 A Systems-Biology Framework for Post-Genomic Microbiology

Pennycook, Steve

328

Solar Energy Materials & Solar Cells 91 (2007) 15991610 Improving solar cell efficiency using photonic band-gap materials  

E-Print Network (OSTI)

Solar Energy Materials & Solar Cells 91 (2007) 1599­1610 Improving solar cell efficiency using Propulsion Laboratory, California Institute of Technology, Mail Stop T1714 106, 4800 Oak Grove Drive and reliable solar-cell devices is presented. We show that due their ability to modify the spectral and angular

Dowling, Jonathan P.

329

Technical evaluation of a dual-junction same-band-gap amorphous silicon photovoltaic system at NREL  

DOE Green Energy (OSTI)

On December 7, 1992, a 1.8-kW{sub ac} utility-interconnect photovoltaic (PV) system using amorphous silicon modules was brought on-line at the National Renewable Energy Laboratory`s photovoltaic test site. This system was deployed to conduct an in-situ technical evaluation of the PV array (in a high voltage configuration) and system performance and reliability in a utility-interconnect application. The system is unique due to the installation of construction-grade insulation on the back of each PV module. This use of insulation is an attempt to levelize the annual array power output by elevating the operating temperature of the modules. This paper presents array and system performance data. Emphasis is placed on quantifying the effects of individual losses as well as seasonal changes on PV array and system performance.

Strand, T.; Mrig, L.; Hansen, R.; Emery, K.

1994-12-01T23:59:59.000Z

330

Effects of filling in CoSb[subscript 3]: Local structure, band gap, and phonons from first principles  

E-Print Network (OSTI)

We use ab initio computations to investigate the effect of filler ions on the properties of CoSb3 skutterudites. We analyze global and local structural effects of filling, using the Ba-filled system as an example. We show ...

Kozinsky, Boris

331

DESIGN, GROWTH, FABRICATION AND CHARACTERIZATION OF HIGH-BAND GAP InGaN/GaN SOLAR CELLS  

E-Print Network (OSTI)

is placed above a light emitting diode (LED, 850 nm) array for the excitation of electron-hole pairs

Honsberg, Christiana

332

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

SciTech Connect

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.

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

2008-01-01T23:59:59.000Z

333

Pulsed laser ablation of binary semiconductors: mechanisms of vaporisation and cluster formation  

SciTech Connect

Formation of small clusters during pulsed ablation of two binary semiconductors, zinc oxide and indium phosphide, in vacuum by UV, visible, and IR laser radiation is comparatively studied. The irradiation conditions favourable for generation of neutral and charged Zn{sub n}O{sub m} and In{sub n}P{sub m} clusters of different stoichiometry in the ablation products are found. The size and composition of the clusters, their expansion dynamics and reactivity are analysed by time-of-flight mass spectrometry. A particular attention is paid to the mechanisms of ZnO and InP ablation as a function of laser fluence, with the use of different ablation models. It is established that ZnO evapourates congruently in a wide range of irradiation conditions, while InP ablation leads to enrichment of the target surface with indium. It is shown that this radically different character of semiconductor ablation determines the composition of the nanostructures formed: zinc oxide clusters are mainly stoichiometric, whereas In{sub n}P{sub m} particles are significantly enriched with indium. (photonics and nanotechnology)

Bulgakov, A V; Evtushenko, A B; Shukhov, Yu G [S S Kutateladze Institute of Thermophysics, Siberian Branch, Russian Academy of Sciences, Novosibirsk (Russian Federation); Ozerov, I; Marin, W [Universite de la Mediterranee, CINaM, UPR CNRS 3118, Marseille (France)

2010-12-29T23:59:59.000Z

334

Impact of energy filtering and carrier localization on the thermoelectric properties of granular semiconductors  

Science Conference Proceedings (OSTI)

Energy filtering has been widely considered as a suitable tool to increase the thermoelectric performances of several classes of materials. In its essence, energy filtering provides a way to increase the Seebeck coefficient by introducing a strongly energy-dependent scattering mechanism. Under certain conditions, however, potential barriers may lead to carrier localization, that may also affect the thermoelectric properties of a material. A model is proposed, actually showing that randomly distributed potential barriers (as those found, e.g., in polycrystalline films) may lead to the simultaneous occurrence of energy filtering and carrier localization. Localization is shown to cause a decrease of the actual carrier density that, along with the quantum tunneling of carriers, may result in an unexpected increase of the power factor with the doping level. The model is corroborated toward experimental data gathered by several authors on degenerate polycrystalline silicon and lead telluride. - Graphical abstract: In heavily doped semiconductors potential barriers may lead to both carrier energy filtering and localization. This may lead to an enhancement of the thermoelectric properties of the material, resulting in an unexpected increase of the power factor with the doping level. Highlights: Black-Right-Pointing-Pointer Potential barriers are shown to lead to carrier localization in thermoelectric materials. Black-Right-Pointing-Pointer Evidence is put forward of the formation of a mobility edge. Black-Right-Pointing-Pointer Energy filtering and localization may explain the enhancement of power factor in degenerate semiconductors.

Narducci, Dario, E-mail: dario.narducci@unimib.it [Department of Materials Science, University of Milano Bicocca, via Cozzi 53, 20125 Milano (Italy) [Department of Materials Science, University of Milano Bicocca, via Cozzi 53, 20125 Milano (Italy); Consorzio DeltaTi Research (Italy); Selezneva, Ekaterina [Department of Materials Science, University of Milano Bicocca, via Cozzi 53, 20125 Milano (Italy)] [Department of Materials Science, University of Milano Bicocca, via Cozzi 53, 20125 Milano (Italy); Cerofolini, Gianfranco [Department of Materials Science, University of Milano Bicocca, via Cozzi 53, 20125 Milano (Italy) [Department of Materials Science, University of Milano Bicocca, via Cozzi 53, 20125 Milano (Italy); Consorzio DeltaTi Research (Italy); Frabboni, Stefano; Ottaviani, Giampiero [Department of Physics, University of Modena and Reggio Emilia, via Campi 213, 41100 Modena (Italy)] [Department of Physics, University of Modena and Reggio Emilia, via Campi 213, 41100 Modena (Italy)

2012-09-15T23:59:59.000Z

335

Structure-fluctuation-induced abnormal thermoelectric properties in semiconductor copper selenide  

Science Conference Proceedings (OSTI)

Thermoelectric effects and related technologies have attracted a great interest due to the world-wide energy harvesting. Thermoelectricity has usually been considered in the context of stable material phases. Here we report that the fluctuation of structures during the second-order phase transition in Cu2Se semiconductor breaks the conventional trends of thermoelectric transports in normal phases, leading to a critically phase-transition-enhanced thermoelectric figure of merit zT above unity at 400K, a three times larger value than for the normal phases. Dynamic structural transformations introduce intensive fluctuations and extreme complexity, which enhance the carrier entropy and thus the thermopower, and strongly scatter carriers and phonons as well to make their transports behave critically.

Liu, Huili [Chinese Academy of Sciences; Shi, Xun [Chinese Academy of Sciences; Kirkham, Melanie J [ORNL; Wang, Hsin [ORNL; Li, Qiang [Brookhaven National Laboratory (BNL); Uher, Ctirad [University of Michigan; Zhang, Wenqing [Shanghai Institute of Ceramics, Chinese Academy of Sciences (SICCAS); Chen, Lidong [Chinese Academy of Sciences

2013-01-01T23:59:59.000Z

336

Agency-Wide Screening | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Agency-Wide Screening Agency-Wide Screening Agency-Wide Screening October 16, 2013 - 4:36pm Addthis Federal agencies face energy-related requirements on new construction projects and major renovations. These Federal requirements range from reductions in fossil-fuel use to specifying the use of certain renewable energy technologies. As some agencies have already found out, not all sites or construction projects are created equal. Because many of the requirements are agency-wide, an effective and efficient way to meet these requirements is to consider and identify appropriate locations for these technologies across all agency land and building assets. FEMP can help Federal agencies conduct a renewable energy screening at all of its sites, or just at all of its upcoming construction project

337

China Joins WorldWideScience Alliance  

Office of Scientific and Technical Information (OSTI)

the addition of more Chinese sources to WorldWideScience.org after a successful test period. DOE's Office of Science, through (OSTI), serves as the Operating Agent for...

338

WorldWideScience.org Goes Multilingual  

Office of Scientific and Technical Information (OSTI)

FOR IMMEDIATE RELEASE Friday, June 11, 2010 WorldWideScience.org Goes Multilingual OAK RIDGE, TN - Now you can find non-English scientific literature from databases in...

339

Ultra-wide bandwidth piezoelectric energy harvesting  

E-Print Network (OSTI)

Here, we present an ultra wide-bandwidth energy harvester by exploiting the nonlinear stiffness of a doubly clamped microelectromechanical systems (MEMSs) resonator. The stretching strain in a doubly clamped beam shows a ...

Hajati, Arman

340

Optical Properties and Potential Applications of Doped Semiconductor Nanoparticles  

SciTech Connect

Recent studies on the optical properties, in particular luminescence, of a variety of doped semiconductor nanoparticles are reviewed. The effects of quantum confinement, temperature, and pressure on luminescent properties are discussed. In addition, electroluminescence, cathodoluminescence, magnetoluminescence and related applications involving doped semiconductor nanoparticles are presented. A new phenomenon, upconversion luminescence of doped nanoparticles, is reviewed and its potential applications are discussed. While more research efforts are necessary in order to fully understand the fundamentals and explore the great technological potential behind doped nanoparticles, recent results already show that this is a new and exciting field with applications in many fields. In particular, the emerging field of ''spintronics'', where spin states are exploited in analogy to conventional electronic states, is discussed and the advantages of using doped semiconductor nanoparticles are elucidated.

Chen, Wei; Zhang, Jin Z.; Joly, Alan G.

2004-11-08T23:59:59.000Z

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


341

Efficient semiconductor light-emitting device and method  

DOE Patents (OSTI)

A semiconductor light-emitting device and method. The semiconductor light-emitting device is provided with at least one control layer or control region which includes an annular oxidized portion thereof to channel an injection current into the active region, and to provide a lateral refractive index profile for index guiding the light generated within the device. A periodic composition grading of at least one of the mirror stacks in the device provides a reduced operating voltage of the device. The semiconductor light-emitting device has a high efficiency for light generation, and may be formed either as a resonant-cavity light-emitting diode (RCLED) or as a vertical-cavity surface-emitting laser (VCSEL).

Choquette, Kent D. (Albuquerque, NM); Lear, Kevin L. (Albuquerque, NM); Schneider, Jr., Richard P. (Albuquerque, NM)

1996-01-01T23:59:59.000Z

342

Efficient semiconductor light-emitting device and method  

DOE Patents (OSTI)

A semiconductor light-emitting device and method are disclosed. The semiconductor light-emitting device is provided with at least one control layer or control region which includes an annular oxidized portion thereof to channel an injection current into the active region, and to provide a lateral refractive index profile for index guiding the light generated within the device. A periodic composition grading of at least one of the mirror stacks in the device provides a reduced operating voltage of the device. The semiconductor light-emitting device has a high efficiency for light generation, and may be formed either as a resonant-cavity light-emitting diode (RCLED) or as a vertical-cavity surface-emitting laser (VCSEL). 12 figs.

Choquette, K.D.; Lear, K.L.; Schneider, R.P. Jr.

1996-02-20T23:59:59.000Z

343

Wavelength-resonant surface-emitting semiconductor laser  

DOE Patents (OSTI)

A wavelength resonant semiconductor gain medium is disclosed. The essential feature of this medium is a multiplicity of quantum-well gain regions separated by semiconductor spacer regions of higher bandgap. Each period of this medium consisting of one quantum-well region and the adjacent spacer region is chosen such that the total width is equal to an integral multiple of 1/2 the wavelength in the medium of the radiation with which the medium is interacting. Optical, electron-beam and electrical injection pumping of the medium is disclosed. This medium may be used as a laser medium for single devices or arrays either with or without reflectors, which may be either semiconductor or external.

Brueck, Steven R. J. (Albuquerque, NM); Schaus, Christian F. (Albuquerque, NM); Osinski, Marek A. (Albuquerque, NM); McInerney, John G. (Cedar Crest, NM); Raja, M. Yasin A. (Albuquerque, NM); Brennan, Thomas M. (Albuquerque, NM); Hammons, Burrell E. (Tijeras, NM)

1989-01-01T23:59:59.000Z

344

OPTICAL AND DYNAMIC PROPERTIES OF UNDOPED AND DOPED SEMICONDUCTOR NANOSTRUCTURES  

Science Conference Proceedings (OSTI)

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

Grant, C D; Zhang, J Z

2007-09-28T23:59:59.000Z

345

Reactive codoping of GaAlInP compound semiconductors  

DOE Patents (OSTI)

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.

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

2008-02-12T23:59:59.000Z

346

Below-bandgap excitation of bulk semiconductors by twisted light  

E-Print Network (OSTI)

I theoretically investigate the response of bulk semiconductors to excitation by twisted light below the energy bandgap. To this end, I modify a well-known model of light-semiconductor interaction to account for the conservation of the light's momentum. I show that the excited states can be thought of as a superposition of slightly perturbed exciton states undergoing a complex center-of-mass motion. In addition, the absorption would occur at a slightly shifted energy (compared to plane waves) and would exhibit complex spatial patterns in the polarization and current.

Quinteiro, G F

2013-01-01T23:59:59.000Z

347

Low temperature production of large-grain polycrystalline semiconductors  

SciTech Connect

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

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

2007-04-10T23:59:59.000Z

348

Toward a Unified Treatment of Electronic Processes in Organic Semiconductors  

DOE Green Energy (OSTI)

A quantitative study of n-type doping in highly crystalline organic semiconductor films establishes the predominant influence of electrostatic forces in these low-dielectric materials. Based on these findings, a self-consistent model of doped (purposely or not) organic semiconductors is proposed in which: (1) the equilibrium free carrier density, nf, is a small fraction of the total charge density; (2) a superlinear increase in conductivity with doping density is universal; (3) nf increases with applied electric field; and (4) the carrier mobility is field-dependent regardless of crystallinity.

Gregg. B.A.

2005-01-01T23:59:59.000Z

349

Synthesis of anatase nanoparticles with extremely wide solid solution range and ScTiNbO{sub 6} with alpha-PbO{sub 2} structure  

Science Conference Proceedings (OSTI)

Anatase-type nanoparticles Sc{sub X}Ti{sub 1-2X}Nb{sub X}O{sub 2} with wide solid solution range (X=0-0.35) were hydrothermally formed at 180 deg. C for 5 h. The lattice parameters a{sub 0} and c{sub 0}, and the optical band gap of anatase gradually and linearly increased with the increase of the content of niobium and scandium from X=0 to 0.35. Their photocatalytic activity and adsorptivity by the measurement of the concentration of methylene blue (MB) that remained in the solution in the dark or under UV-light irradiation were evaluated. The anatase phase existed stably up to 900 deg. C for the samples with X=0.25-0.30 and 750 deg. C for that with X=0.35 during heat treatment in air. The phase with alpha-PbO{sub 2} structure and the rutile phases coexisted in the samples with X=0.25-0.30 after heated at temperatures above 900-950 deg. C. The alpha-PbO{sub 2} structure having composition ScTiNbO{sub 6} with possibly some cation order similar to that seen in wolframite existed as almost completely single phase after heat treatment at temperatures 900-1500 deg. C through phase transformation from anatase-type ScTiNbO{sub 6}. - Graphical abstract: Anatase-type Sc{sub X}Ti{sub 1-2X}Nb{sub X}O{sub 2} solid solutions with wide solid solution range (X=0-0.35) were hydrothermally formed as nanoparticles from the precursor solutions of Sc(NO{sub 3}){sub 3}, TiOSO{sub 4}, NbCl{sub 5} at 180 deg. C for 5 h using the hydrolysis of urea. Anatase-type ScTiNbO{sub 6} was synthesized under hydrothermal condition. ScTiNbO{sub 6} having alpha-PbO{sub 2} structure with possibly some cation order similar to that seen in wolframite was formed through phase transformation above 900 deg. C.

Hirano, Masanori, E-mail: hirano@aitech.ac.j [Department of Applied Chemistry, Faculty of Engineering, Aichi Institute of Technology, Yakusa, Toyota 470-0392 (Japan); Ito, Takaharu [Department of Applied Chemistry, Faculty of Engineering, Aichi Institute of Technology, Yakusa, Toyota 470-0392 (Japan)

2009-06-15T23:59:59.000Z

350

System design and simulation of constant temperature box using semiconductor refrigeration device  

Science Conference Proceedings (OSTI)

This paper presents the variation law of temperature in three-dimensional space, which is cooled by the refrigeration provided by the cold side of a semiconductor. The mathematical model of the temperature field of the semiconductor refrigeration ... Keywords: constant temperature box, forced convection, mathematical modelling, numerical simulation, semiconductor refrigeration, system design

Hui Zhang; Kuang-Chao Fan; Jun Wang

2010-03-01T23:59:59.000Z

351

Draft Site-Wide Environmental Impact Statement  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Site-Wide Environmental Impact Statement Site-Wide Environmental Impact Statement for the Y-12 National Security Complex October 2009 U.S. Department of Energy National Nuclear Security Administration Y-12 Site Office DOE/EIS-0387 COVER SHEET RESPONSIBLE AGENCY: United States (U.S.) Department of Energy (DOE), National Nuclear Security Administration (NNSA) TITLE: Draft Site-wide Environmental Impact Statement for the Y-12 National Security Complex (DOE/EIS-0387) (Draft Y-12 SWEIS) CONTACT: For further information on this SWEIS, For general information on the DOE contact: National Environmental Policy Act (NEPA) process, contact: Pam Gorman Carol Borgstrom, Director Y-12 SWEIS Document Manager Office of NEPA Policy and Compliance, GC-20 Y-12 Site Office U.S. Department of Energy

352

Ados Co Ltd Dong Yang Semiconductor | Open Energy Information  

Open Energy Info (EERE)

Ados Co Ltd Dong Yang Semiconductor Ados Co Ltd Dong Yang Semiconductor Jump to: navigation, search Name Ados Co Ltd (Dong Yang Semiconductor) Place Seoul, Seoul, Korea (Republic) Product Korean manufacturer of semiconductors; through Ersol's technology, will develop PV plants and begin to roll out crystalline silicon wafers and cells by H2 2007. Coordinates 37.557121°, 126.977379° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":37.557121,"lon":126.977379,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

353

Generator of pumping pulses for powerful semiconductor lasers  

Science Conference Proceedings (OSTI)

The generator of electric and optic pulses are built using powerful MOS transistors and an ILPI-103 semiconductor laser generates pumping pulses with an amplitude of 15 A and optic pulses with a duration of 9 to 30 nsec at a repetition rate of up to 90 kHz. The output signal is TTL. The device is designed for open optic communication lines.

An, V.I.; Kolesnikov, Yu.Yu. [Voronezh Scientific Research Institute of Communications, Voronezh (Russian Federation)

1995-06-01T23:59:59.000Z

354

[Electron transfer rates at semiconductor/liquid interfaces]. Progress report  

DOE Green Energy (OSTI)

Work has focused on several aspects of the fundamental chemistry and physics semiconductor/liquid junction behavior. These projects have been directed primarily towards GaAs/liquid contacts, because GaAs/liquid systems provide high energy conversion efficiencies and offer an opportunity to gain mechanistic understanding of the factors that are important to control in an efficient photoelectrochemical energy conversion system.

Lewis, N.S.

1992-08-01T23:59:59.000Z

355

(Electron transfer rates at semiconductor/liquid interfaces)  

DOE Green Energy (OSTI)

Work has focused on several aspects of the fundamental chemistry and physics semiconductor/liquid junction behavior. These projects have been directed primarily towards GaAs/liquid contacts, because GaAs/liquid systems provide high energy conversion efficiencies and offer an opportunity to gain mechanistic understanding of the factors that are important to control in an efficient photoelectrochemical energy conversion system.

Lewis, N.S.

1992-01-01T23:59:59.000Z

356

Electronic displays using optically pumped luminescent semiconductor nanocrystals  

DOE Patents (OSTI)

A multicolor electronic display is based on an array of luminescent semiconductor nanocrystals. Nanocrystals which emit light of different colors are grouped into pixels. The nanocrystals are optically pumped to produce a multicolor display. Different sized nanocrystals are used to produce the different colors. A variety of pixel addressing systems can be used.

Weiss, Shimon (Pinole, CA); Schlamp, Michael C. (Plainsboro, NJ); Alivisatos, A. Paul (Oakland, CA)

2011-09-27T23:59:59.000Z

357

Quantum Optics: Colloidal Fluorescent Semiconductor Nanocrystals (Quantum Dots)  

E-Print Network (OSTI)

U ncorrected Proof Chapter 3 Quantum Optics: Colloidal Fluorescent Semiconductor Nanocrystals (Quantum Dots) in Single-Molecule Detection and Imaging Laurent A. Bentolila, Xavier Michalet, and Shimon quantum dots (QDs), have emerged as new powerful fluorescent probes for in vitro and in vivo biological

Michalet, Xavier

358

User experience research in the semiconductor factory: a contradiction?  

Science Conference Proceedings (OSTI)

No doubt, user experience (UX) has become of high relevance within the HCI community. Within this paper, we present initial results from a qualitative study on UX in the factory context, more precisely in a semiconductor factory. We highlight the challenges ... Keywords: factory context, probing, user experience, user study

Marianna Obrist; Wolfgang Reitberger; Daniela Wurhofer; Florian Förster; Manfred Tscheligi

2011-09-01T23:59:59.000Z

359

The new -NMR facility at TRIUMF and applications in semiconductors  

E-Print Network (OSTI)

The new -NMR facility at TRIUMF and applications in semiconductors K.H. Chow a, Z. Salman b R facililty for conducting beta-detected nuclear magnetic resonance (-NMR) investigations of condensed matter facility are described, and some preliminary results on 8Li+ in GaAs are presented. Key words: -NMR

Baartman, Richard Abram

360

Chemosensors, biosensors, and microsystems based on standard semiconductor technology (CMOS)  

Science Conference Proceedings (OSTI)

Microfabrication techniques and, in particular, complementary metal oxide semiconductor (CMOS) technology have been used to devise chemosensors, biosensors, and microsystems in a generic approach. Examples of micromachined bio/chemosensors, such as cantilevers ... Keywords: CMOS, bioelectronics, biomicrosystem, biosensor, cells, chemical sensor, microelectronics

Andreas Hierlemann

2007-02-01T23:59:59.000Z

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


361

Instrumentation and Control Strategies for Plant-Wide and Fleet-Wide Cost Reduction  

Science Conference Proceedings (OSTI)

A more recent product is now available that contains this report, along with additional presentation materials to facilitate its use. See Product 1018109. This report provides guidance arising from the EPRI initiative on IC Strategies for Plant-Wide and Fleet-Wide Cost Reduction. The document describes a wide range of options while emphasizing integrated modernization across the plant or fleet. Coordinated improvements to shared communications and computing infrastructure, plant processes, and organizat...

2007-10-29T23:59:59.000Z

362

Traffic data repository at the WIDE project  

Science Conference Proceedings (OSTI)

It becomes increasingly important for both network researchers and operators to know the trend of network traffic and to find anomaly in their network traffic. This paper describes an on-going effort within the WIDE project to collect a set of free tools ...

Kenjiro Cho; Koushirou Mitsuya; Akira Kato

2000-06-01T23:59:59.000Z

363

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

SciTech Connect

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.

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

2004-03-02T23:59:59.000Z

364

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

DOE Patents (OSTI)

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

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

2011-12-06T23:59:59.000Z

365

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

DOE Patents (OSTI)

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.

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

2002-01-01T23:59:59.000Z

366

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

SciTech Connect

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

Weiss, Shimon; Bruchez, Marcel; Alivisatos, Paul

2012-10-16T23:59:59.000Z

367

Methods of use of semiconductor nanocrystal probes for treating a material  

Science Conference Proceedings (OSTI)

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

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

2007-04-27T23:59:59.000Z

368

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

SciTech Connect

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

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

2011-12-20T23:59:59.000Z

369

DFAS Wide-Area Workflow Issues  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

DFAS Wide-Area Workflow DFAS Wide-Area Workflow Issues Mark Shvartzman Sr. Project Manager, CEM, CEA Southern California Edison Presented at the Spring FUPWG Meeting April 20, 2011 What We Are Going to Discuss * Review Delivery Order or Task Order for accounting lines information. * Contact Contracting Officer or Contracting specialist and request Pay DoDAAC and Ext. information * Create Payment Log by ACRN * Start creating Invoice How the WAWF works and how to navigate through: 2 CONTRACT N68711-03-G-4019 DO#0028 Pay Records Bill by CLIN Award $ by CLIN Billed To Date Invoice number Pay Total Balance by CLIN 7500009733 $330,899.11 CLIN 0001AA 674,220.00 674,220.00 7500009733 7500012596 674,220.00 0.00 7500012596 $641,344.69 CLIN 0001AB 325,780.00 298023.8 27,756.20 7500012596 7500015079 325,780.00

370

Industry-Wide Database: Circuit Breakers  

Science Conference Proceedings (OSTI)

Best practice maintenance and asset management decisions are based on risks associated with actual equipment condition and performance. However, little effort has been made to systematically collect and analyze such industry information for high-voltage circuit breakers. This document presents the results of the initial effort of the Electric Power Research Institute (EPRI) to explore the development of an industry-wide database (IDB) for high-voltage circuit breakers (HVCBs). The project identified ...

2012-12-12T23:59:59.000Z

371

TCP performance analysis for wide area networks  

SciTech Connect

Even though networks have been getting faster, perceived throughput at the application level has not increased accordingly. In an attempt to identify many of the performance bottlenecks, we collected and analyzed data over a wide area network (WAN) at T3 (45 Mbps) bandwidth. The information gained will assist in designing new protocols and/or algorithms that are consistent with future high- speed requirements.

Chen, H.Y.; Hutchins, J.A. [Sandia National Labs., Livermore, CA (United States); Testi, N. [Sandia National Labs., Albuquerque, NM (United States)

1993-08-01T23:59:59.000Z

372

Method of plasma etching GA-based compound semiconductors  

DOE Patents (OSTI)

A method of plasma etching Ga-based compound semiconductors includes providing a process chamber and a source electrode adjacent thereto. The chamber contains a Ga-based compound semiconductor sample in contact with a platen which is electrically connected to a first power supply, and the source electrode is electrically connected to a second power supply. SiCl.sub.4 and Ar gases are flowed into the chamber. RF power is supplied to the platen at a first power level, and RF power is supplied to the source electrode. A plasma is generated. Then, RF power is supplied to the platen at a second power level lower than the first power level and no greater than about 30 W. Regions of a surface of the sample adjacent to one or more masked portions of the surface are etched at a rate of no more than about 25 nm/min to create a substantially smooth etched surface.

Qiu, Weibin; Goddard, Lynford L.

2013-01-01T23:59:59.000Z

373

Method of plasma etching Ga-based compound semiconductors  

SciTech Connect

A method of plasma etching Ga-based compound semiconductors includes providing a process chamber and a source electrode adjacent to the process chamber. The process chamber contains a sample comprising a Ga-based compound semiconductor. The sample is in contact with a platen which is electrically connected to a first power supply, and the source electrode is electrically connected to a second power supply. The method includes flowing SiCl.sub.4 gas into the chamber, flowing Ar gas into the chamber, and flowing H.sub.2 gas into the chamber. RF power is supplied independently to the source electrode and the platen. A plasma is generated based on the gases in the process chamber, and regions of a surface of the sample adjacent to one or more masked portions of the surface are etched to create a substantially smooth etched surface including features having substantially vertical walls beneath the masked portions.

Qiu, Weibin; Goddard, Lynford L.

2012-12-25T23:59:59.000Z

374

Semiconductor Nanocrystals-Based White Light Emitting Diodes  

Science Conference Proceedings (OSTI)

In response to the demands for energy and the concerns of global warming and climate change, energy efficient and environmentally friendly solid state lighting, such as white light emitting diodes (WLEDs), is considered to be the most promising and suitable light source. Because of their small size, high efficiency, and long lifetime, WLEDs based on colloidal semiconductor nanocrystals (or quantum dots) are emerging as a completely new technology platform for the development of flat-panel displays and solid state lighting, exhibiting the potential to replace the conventionally used incandescent and fluorescent lamps. This replacement could cut the ever-increasing energy consumption, solve the problem of rapidly depleting fossil fuel reserves, and improve the quality of the global environment. In this review, we highlight the recent progress in semiconductor nanocrystals-based WLEDs, compare different approaches for generating white light, and discuss the benefits and challenges of the solid state lighting technology.

Dai, Quanqin [ORNL; Hu, Michael Z. [ORNL; Duty, Chad E [ORNL

2010-01-01T23:59:59.000Z

375

Semiconductor-Nanocrystals-Based White Light-Emitting Diodes  

Science Conference Proceedings (OSTI)

In response to the demands for energy and the concerns of global warming and climate change, energy efficient and environmentally friendly solid-state lighting, such as white lightemitting diodes (WLEDs), is considered to be the most promising and suitable light source. Because of their small size, high efficiency, and long lifetime, WLEDs based on colloidal semiconductor nanocrystals (or quantum dots) are emerging as a completely new technology platform for the development of flat-panel displays and solid-state lighting, exhibiting the potential to replace the conventionally used incandescent and fluorescent lamps. This replacement can cut the ever-increasing level of energy consumption, solve the problem of rapidly depleting fossil fuel reserves, and improve the quality of the global environment. In this review, the recent progress in semiconductor-nanocrystals-based WLEDs is highlighted, the different approaches for generating white light are compared, and the benefits and challenges of the solid-state lighting technology are discussed.

Dai, Quanqin [ORNL; Duty, Chad E [ORNL; Hu, Michael Z. [ORNL

2010-01-01T23:59:59.000Z

376

Method for mapping charge pulses in semiconductor radiation detectors  

Science Conference Proceedings (OSTI)

An efficient method for determining the distribution of charge pulses produced by semiconductor detectors is presented. The method is based on a quasi-steady-state model for semiconductor detector operation. A complete description of the model and underlying assumptions is given. Mapping of charge pulses is accomplished by solving an adjoint carrier continuity equation. The solution of the adjoint equation yields Green`s function, a time- and position-dependent map that contains all possible charge pulses that can be produced by the detector for charge generated at discrete locations (e.g., by gamma-ray interactions). Because the map is generated by solving a single, time-dependent problem, the potential for reduction in computational effort over direct mapping methods is significant, particularly for detectors with complex electrode structures. In this paper, the adjoint equation is derived and the mapping method is illustrated for a simple case.

Prettyman, T.H.

1998-12-01T23:59:59.000Z

377

Hybrid high-temperature superconductor-semiconductor tunnel diode  

E-Print Network (OSTI)

We report the demonstration of hybrid high-Tc-superconductor-semiconductor tunnel junctions, enabling new interdisciplinary directions in condensed matter research. The devices were fabricated by our newly-developed mechanical bonding technique, resulting in high-Tc-semiconductor planar junctions acting as superconducting tunnel diodes. Tunneling-spectra characterization of the hybrid junctions of Bi2Sr2CaCu2O8+{\\delta} combined with bulk GaAs, or a GaAs/AlGaAs quantum well, exhibits excess voltage and nonlinearity - in good agreement with theoretical predictions for a d-wave superconductor-normal material junction, and similar to spectra obtained in scanning tunneling microscopy. Additional junctions are demonstrated using Bi2Sr2CaCu2O8+{\\delta} combined with graphite or Bi2Te3. Our results pave the way for new methods in unconventional superconductivity studies, novel materials and quantum technology applications.

Alex Hayat; Parisa Zareapour; Shu Yang F. Zhao; Achint Jain; Igor G. Savelyev; Marina Blumin; Zhijun Xu; Alina Yang; G. D. Gu; Harry E. Ruda; Shuang Jia; R. J. Cava; Aephraim M. Steinberg; Kenneth S. Burch

2013-01-09T23:59:59.000Z

378

Semiconductor light source with electrically tunable emission wavelength  

DOE Patents (OSTI)

A semiconductor light source comprises a substrate, lower and upper claddings, a waveguide region with imbedded active area, and electrical contacts to provide voltage necessary for the wavelength tuning. The active region includes single or several heterojunction periods sandwiched between charge accumulation layers. Each of the active region periods comprises higher and lower affinity semiconductor layers with type-II band alignment. The charge carrier accumulation in the charge accumulation layers results in electric field build-up and leads to the formation of generally triangular electron and hole potential wells in the higher and lower affinity layers. Nonequillibrium carriers can be created in the active region by means of electrical injection or optical pumping. The ground state energy in the triangular wells and the radiation wavelength can be tuned by changing the voltage drop across the active region.

Belenky, Gregory (Port Jefferson, NY); Bruno, John D. (Bowie, MD); Kisin, Mikhail V. (Centereach, NY); Luryi, Serge (Setauket, NY); Shterengas, Leon (Centereach, NY); Suchalkin, Sergey (Centereach, NY); Tober, Richard L. (Elkridge, MD)

2011-01-25T23:59:59.000Z

379

Semiconductor laser devices having lateral refractive index tailoring  

DOE Patents (OSTI)

A broad-area semiconductor laser diode includes an active lasing region interposed between an upper and a lower cladding layer, the laser diode further comprising structure for controllably varying a lateral refractive index profile of the diode to substantially compensate for an effect of junction heating during operation. In embodiments disclosed the controlling structure comprises resistive heating strips or non-radiative linear junctions disposed parallel to the active region. Another embodiment discloses a multi-layered upper cladding region selectively disordered by implanted or diffused dopant impurities. Still another embodiment discloses an upper cladding layer of variable thickness that is convex in shape and symmetrically disposed about a central axis of the active region. The teaching of the invention is also shown to be applicable to arrays of semiconductor laser diodes.

Ashby, C.I.H.; Hadley, G.R.; Hohimer, J.P.; Owyoung, A.

1989-06-15T23:59:59.000Z

380

Energy Conservation Through Water Usage Reduction in the Semiconductor Industry  

E-Print Network (OSTI)

The semiconductor industry uses large amounts of Ultrapure Water (UPW) in the wafer fabrication process. Producing UPW involves energy-intensive operations, such as membrane separations, ultraviolet lamps, and continuous pumping and recirculation systems. Indirect energy costs can also be allocated to steps in the UPW process. Motorola recognizes that by reducing UPW consumption, energy savings will result. Energy conservation can also be achieved by improving the UPW generation process itself and by recycling or reclaiming UPW and other water streams.

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

1998-04-01T23:59:59.000Z

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


381

Semiconductor-based, large-area, flexible, electronic devices  

SciTech Connect

Novel articles and methods to fabricate the same resulting in flexible, large-area, triaxially textured, single-crystal or single-crystal-like, semiconductor-based, electronic devices are disclosed. Potential applications of resulting articles are in areas of photovoltaic devices, flat-panel displays, thermophotovoltaic devices, ferroelectric devices, light emitting diode devices, computer hard disc drive devices, magnetoresistance based devices, photoluminescence based devices, non-volatile memory devices, dielectric devices, thermoelectric devices and quantum dot laser devices.

Goyal, Amit (Knoxville, TN)

2011-03-15T23:59:59.000Z

382

Method for measuring the drift mobility in doped semiconductors  

DOE Patents (OSTI)

A method for measuring the drift mobility of majority carriers in semiconductors consists of measuring the current transient in a Schottky-barrier device following the termination of a forward bias pulse. An example is given using an amorphous silicon hydrogenated material doped with 0.2% 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.

Crandall, Richard S. (Princeton, NJ)

1982-01-01T23:59:59.000Z

383

Method for measuring the drift mobility in doped semiconductors  

DOE Patents (OSTI)

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

Crandall, R.S.

1982-03-09T23:59:59.000Z

384

Electronic Structure and Magnetism in Diluted Magnetic Semiconductors  

NLE Websites -- All DOE Office Websites (Extended Search)

Electronic Structure and Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print Wednesday, 29 November 2006 00:00 The possibility of using electrons' spins in addition to their charge in information technology has created much enthusiasm for a new field of electronics popularly known as "spintronics." An intensely studied approach to obtaining spin-polarized carriers for data-storage devices is the use of diluted magnetic semiconductors created by doping ions like Mn, Fe, or Co having a net spin into a semiconducting host such as GaAs, ZnO, or GaN. The interaction among these spins leads to ferromagnetic order at low temperatures, which is necessary to create spin-polarized carriers. A research team working at ALS Beamline 4.0.2 and European Synchrotron Radiation Facility Beamline ID8 made a big leap forward in clarifying the microscopic picture of magnetism and anisotropy in Mn-doped GaAs by resolving localized and hybridized d states using angle-dependent x-ray magnetic circular dichroism (XMCD) measurements.

385

Electronic Structure and Magnetism in Diluted Magnetic Semiconductors  

NLE Websites -- All DOE Office Websites (Extended Search)

Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print The possibility of using electrons' spins in addition to their charge in information technology has created much enthusiasm for a new field of electronics popularly known as "spintronics." An intensely studied approach to obtaining spin-polarized carriers for data-storage devices is the use of diluted magnetic semiconductors created by doping ions like Mn, Fe, or Co having a net spin into a semiconducting host such as GaAs, ZnO, or GaN. The interaction among these spins leads to ferromagnetic order at low temperatures, which is necessary to create spin-polarized carriers. A research team working at ALS Beamline 4.0.2 and European Synchrotron Radiation Facility Beamline ID8 made a big leap forward in clarifying the microscopic picture of magnetism and anisotropy in Mn-doped GaAs by resolving localized and hybridized d states using angle-dependent x-ray magnetic circular dichroism (XMCD) measurements.

386

Electronic Structure and Magnetism in Diluted Magnetic Semiconductors  

NLE Websites -- All DOE Office Websites (Extended Search)

Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print The possibility of using electrons' spins in addition to their charge in information technology has created much enthusiasm for a new field of electronics popularly known as "spintronics." An intensely studied approach to obtaining spin-polarized carriers for data-storage devices is the use of diluted magnetic semiconductors created by doping ions like Mn, Fe, or Co having a net spin into a semiconducting host such as GaAs, ZnO, or GaN. The interaction among these spins leads to ferromagnetic order at low temperatures, which is necessary to create spin-polarized carriers. A research team working at ALS Beamline 4.0.2 and European Synchrotron Radiation Facility Beamline ID8 made a big leap forward in clarifying the microscopic picture of magnetism and anisotropy in Mn-doped GaAs by resolving localized and hybridized d states using angle-dependent x-ray magnetic circular dichroism (XMCD) measurements.

387

Nonlinear fibre-optic devices pumped by semiconductor disk lasers  

Science Conference Proceedings (OSTI)

Semiconductor disk lasers offer a unique combination of characteristics that are particularly attractive for pumping Raman lasers and amplifiers. The advantages of disk lasers include a low relative noise intensity (-150 dB Hz{sup -1}), scalable (on the order of several watts) output power, and nearly diffraction-limited beam quality resulting in a high ({approx}70 % - 90 %) coupling efficiency into a single-mode fibre. Using this technology, low-noise fibre Raman amplifiers operating at 1.3 {mu}m in co-propagation configuration are developed. A hybrid Raman-bismuth doped fibre amplifier is proposed to further increase the pump conversion efficiency. The possibility of fabricating mode-locked picosecond fibre lasers operating under both normal and anomalous dispersion is shown experimentally. We demonstrate the operation of 1.38-{mu}m and 1.6-{mu}m passively mode-locked Raman fibre lasers pumped by 1.29-{mu}m and 1.48-{mu}m semiconductor disk lasers and producing 1.97- and 2.7-ps pulses, respectively. Using a picosecond semiconductor disk laser amplified with an ytterbium-erbium fibre amplifier, the supercontinuum generation spanning from 1.35 {mu}m to 2 {mu}m is achieved with an average power of 3.5 W. (invited paper)

Chamorovskiy, A Yu; Okhotnikov, Oleg G [Optoelectronics Research Center, Tampere University of Technology, Tampere (Finland)

2012-11-30T23:59:59.000Z

388

Wide Area and Distributed Hydrogen Sensors  

DOE Green Energy (OSTI)

Recent advances in optical sensors show promise for the development of new wide area monitoring and distributed optical network hydrogen detection systems. Optical hydrogen sensing technologies reviewed here are: 1) open path Raman scattering systems, 2) back scattering from chemically treated solid polymer matrix optical fiber sensor cladding; and 3) shlieren and shearing interferometry imaging. Ultrasonic sensors for hydrogen release detection are also reviewed. The development status of these technologies and their demonstrated results in sensor path length, low hydrogen concentration detection ability, and response times are described and compared to the corresponding status of hydrogen spot sensor network technologies.

Zalosh, Robert G.; Barilo, Nick F.

2009-09-18T23:59:59.000Z

389

Magnetism of Semiconductor-Based Magnetic Tunnel Junctions under Electric Field from First Principles  

SciTech Connect

Semiconductor magnetic tunnel junctions (MTJs), composed of diluted magnetic semiconductors (DMSs) sandwiching a semiconductor barrier, have potential applications in spintronics but their development has been slow due to the difficulty of controlling the magnetism of DMSs. In terms of density functional calculations for model semiconductor MTJs, (Zn,Co)O/ZnO/(Zn,Co)O and (Ga,Mn)N/GaN/(Ga,Mn)N, we show that the magnetic coupling between the transition metal ions in each DMS electrode of such semiconductor MTJs can be switched from ferromagnetic to antiferromagnetic, or vice versa, under the application of external electric field across the junctions. Our results suggest a possible avenue for the application of semiconductor MTJs.

Kan, E.; Xiang, H.; Yang, J.; Whangbo, M. H.

2009-06-01T23:59:59.000Z

390

Molecular Chemistry to the Fore: New Insights into the Fascinating World of Photoactive Colloidal Semiconductor Nanocrystals  

SciTech Connect

Colloidal semiconductor nanocrystals possess unique properties that are unmatched by other chromophores such as organic dyes or transition-metal complexes. These versatile building blocks have generated much scientific interest and found applications in bioimaging, tracking, lighting, lasing, photovoltaics, photocatalysis, thermoelectrics, and spintronics. Despite these advances, important challenges remain, notably how to produce semiconductor nanostructures with predetermined architecture, how to produce metastable semiconductor nanostructures that are hard to isolate by conventional syntheses, and how to control the degree of surface loading or valence per nanocrystal. Molecular chemists are very familiar with these issues and can use their expertise to help solve these challenges. In this Perspective, we present our group’s recent work on bottom-up molecular control of nanoscale composition and morphology, low-temperature photochemical routes to semiconductor heterostructures and metastable phases, solar-to-chemical energy conversion with semiconductor-based photocatalysts, and controlled surface modification of colloidal semiconductors that bypasses ligand exchange.

Vela-Becerra, Javier [Ames Laboratory

2013-02-01T23:59:59.000Z

391

CASP | U.S. DOE Office of Science (SC)  

NLE Websites -- All DOE Office Websites (Extended Search)

CASP CASP Energy Frontier Research Centers (EFRCs) EFRCs Home Centers Research Science Highlights News & Events Publications Contact BES Home Centers CASP Print Text Size: A A A RSS Feeds FeedbackShare Page Center for Advanced Solar Photophysics (CASP) Director(s): Victor I. Klimov Lead Institution: Los Alamos National Laboratory Mission: To capitalize on recent advances in the science of how nanoparticles interact with light to design highly efficient materials for the conversion of sunlight into electricity. Research Topics: solar (photovoltaic), solar (fuels), solid state lighting, bio-inspired, electrodes - solar, defects, charge transport, materials and chemistry by design, optics, synthesis (novel materials), synthesis (scalable processing) Materials Studied: MATERIALS: semiconductor, wide band-gap semiconductor, metal, oxide,

392

Sensitized photoelectrolysis of water with sunlight. Final report, June 1, 1977-December 31, 1978  

SciTech Connect

A study was made of solar driven water photoelectrolysis cells employing semiconductor electrodes. An extensive review of the literature was undertaken, and the three major problem areas for these devices were identified: corrosion, poor sunlight absorption, and external bias requirement. Although many semiconductors had been tested, none had proven free of all three defects. Two approaches were thus followed for the experimental studies: impurity sensitization of wide band gap stable oxides, and heterostructure formation between unstable sunlight absorbers and corrosion resistant oxides. Water decomposition was achieved with visible light excitation of Cr-doped TiO/sub 2/. Transport properties were studies for TiO/sub 2/ and SrTiO/sub 3/ electrodes doped with V, Cr, Mn, Fe, Co, and Ni. The correlation between bias requirement and electron affinity of oxides was identified. Performance of heterostructure electrodes was shown to be limited either by pin hole problems or by potential barriers between the valence bands.

Ghosh, A.K.; Maruska, H.P.

1978-12-01T23:59:59.000Z

393

Plant Wide Assessment for SIFCO Industries, Inc.  

Science Conference Proceedings (OSTI)

Sifco Industries carreid out a plant wide energy assessment under a collaborative program with the U.S. Department of Energy during October 2004 to September 2005. During the year, personnel from EIS, E3M, DPS, BuyCastings.Com, and Sifco plant facilities and maintenance personnel, as a team collected energy use, construction, process, equipment and operational information about the plant. Based on this information, the team identified 13 energy savings opportunities. Near term savings opportunities have a total potential savings of about $1,329,000 per year and a combined simple payback of about 11 months. Implementation of these recommendations would reduce CO2 emissions by about 16,000,000 pounds per year, which would reduce overall plant CO2 emissions by about 45%. These totals do not include another $830,000 per year in potential savings with an estimated 9-month payback, from converting the forging hammers from steam to compressed air.

Kelly Kissock, Arvind Thekdi et. al.

2005-07-06T23:59:59.000Z

394

Table 4-3 Site Wide Environmental Management Matrix  

NLE Websites -- All DOE Office Websites (Extended Search)

Site-Wide Environmental Assessment of Table 4-3. Site-Wide Environmental Management Matrix National Renewable Energy Laboratory's South Table Mountain Complex FINAL POTENTIAL...

395

Government-Wide Diversity and Inclusion Strategic Plan (2011...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Government-Wide Diversity and Inclusion Strategic Plan (2011), Office of Personnel Management Government-Wide Diversity and Inclusion Strategic Plan (2011), Office of Personnel...

396

Implications of Wide-Area Geographic Diversity for Short- Term...  

NLE Websites -- All DOE Office Websites (Extended Search)

Implications of Wide-Area Geographic Diversity for Short- Term Variability of Solar Power Title Implications of Wide-Area Geographic Diversity for Short- Term Variability of Solar...

397

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

DOE Patents (OSTI)

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

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

2000-01-01T23:59:59.000Z

398

Coherent multi-exciton dynamics in semiconductor nanostructures via two-dimensional Fourier transform optical spectroscopy  

E-Print Network (OSTI)

The Coulomb correlations between photoexcited charged particles in materials such as photosynthetic complexes, conjugated polymer systems, J-aggregates, and bulk or nanostructured semiconductors produce a hierarchy of ...

Stone, Katherine Walowicz

2009-01-01T23:59:59.000Z

399

Comment on "Analysis of quantum coherent semiconductor quantum dot p-i-n junction photovoltaic cells"  

E-Print Network (OSTI)

This is a comment on PRL paper by A.P. Kirk "Analysis of quantum coherent semiconductor quantum dot p-i-n junction photovoltaic cells"

Scully, Marlan O

2010-01-01T23:59:59.000Z

400

Group I-III-VI.sub.2 semiconductor films for solar cell application  

SciTech Connect

This invention relates to an improved thin film solar cell with excellent electrical and mechanical integrity. The device comprises a substrate, a Group I-III-VI.sub.2 semiconductor absorber layer and a transparent window layer. The mechanical bond between the substrate and the Group I-III-VI.sub.2 semiconductor layer is enhanced by an intermediate layer between the substrate and the Group I-III-VI.sub.2 semiconductor film being grown. The intermediate layer contains tellurium or substitutes therefor, such as Se, Sn, or Pb. The intermediate layer improves the morphology and electrical characteristics of the Group I-III-VI.sub.2 semiconductor layer.

Basol, Bulent M. (Redondo Beach, CA); Kapur, Vijay K. (Northridge, CA)

1991-01-01T23:59:59.000Z

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


401

Development of fluorescent semi-conductor nanocrystal conjugates for in vitro and in vivo imaging applications  

E-Print Network (OSTI)

Semiconductor nanocrystals, also known as quantum dots (QDs), are promising imaging probes with characteristic optical properties: tunable bandgap from visible to infrared, narrow and symmetric emission features, broad ...

Han, Hee-Sun, Ph. D. Massachusetts Institute of Technology

2012-01-01T23:59:59.000Z

402

Global product development in semiconductor industry : Intel -- Tick-Tock product development cadence  

E-Print Network (OSTI)

This thesis investigates on changes in semiconductor industry's product development methodology by following Intel's product development from year 2000. Intel was challenged by customer's preference change, competitors new ...

Park, Cheolmin, S.M. Massachusetts Institute of Technology

2008-01-01T23:59:59.000Z

403

Frequency modulation on single sideband using controlled dynamics of an optically injected semiconductor laser  

E-Print Network (OSTI)

locked semicon- ductor lasers with delayed optoelectronicgeneration using semiconductor laser dynamics,” IEEE J. Sel.in optically-injected laser diodes,” Opt. Commun. , vol.

Chan, Sze-Chun; Liu, Jia-Ming

2006-01-01T23:59:59.000Z

404

Light emission patterns from stadium-shaped semiconductor microcavity lasers  

E-Print Network (OSTI)

We study light emission patterns from stadium-shaped semiconductor (GaAs) microcavity lasers theoretically and experimentally. Performing systematic wave calculations for passive cavity modes, we demonstrate that the averaging by low-loss modes, such as those realized in multi-mode lasing, generates an emission pattern in good agreement with the ray model's prediction. In addition, we show that the dependence of experimental far-field emission patterns on the aspect ratio of the stadium cavity is well reproduced by the ray model.

Susumu Shinohara; Takehiro Fukushima; Takahisa Harayama

2007-06-01T23:59:59.000Z

405

Activation of molecular catalysts using semiconductor quantum dots  

DOE Patents (OSTI)

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.

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

2011-10-04T23:59:59.000Z

406

Three-terminal semiconductor laser for wave mixing  

E-Print Network (OSTI)

We suggest and analyze the concept of a semiconductor laser device that incorporates two basic ideas: (i) dual-wavelength generation of two optical fields on the interband transitions with independent control of each field in a three-terminal "transistor" scheme, and (ii) generation of infrared radiation in the 3-300 mum range due to nonlinear wave mixing of the above optical fields in the same laser cavity. Due to inversionless nature of the difference frequency generation and inherently low threshold current, the laser can be capable of continuous room-temperature operation in the mid/far-infrared and THz range.

Belyanin, Alexey; Kocharovsky, V.; Kocharovsky, V.; Scully, Marlan O.

2002-01-01T23:59:59.000Z

407

Bistability of Cation Interstitials in II-VI Semiconductors  

DOE Green Energy (OSTI)

The stability of cation interstitials in II-VI semiconductors is studied using ab initio methods. We find that interstitials in the neutral charge state are more stable in the tetrahedral interstitial site near the cation, whereas in the (2+) charge state, they are more stable near the anion. The diffusion energy barrier changes when the defect charge state changes. Therefore, if electrons/holes are taken from the defect level by light, changing its charge state, the interstitial atom will be able to diffuse almost spontaneously due to a reduced diffusion barrier.

Wei, S. H.; Dalpian, G. M.

2005-11-01T23:59:59.000Z

408

STATEMENT OF CONSIDERATIONS REQUEST BY OSRAM OPTO SEMICONDUCTORS  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

5 14:37 FR IPL DOE CH 630 252 2779 TO RGCP-HQ P.02/04 5 14:37 FR IPL DOE CH 630 252 2779 TO RGCP-HQ P.02/04 * * STATEMENT OF CONSIDERATIONS REQUEST BY OSRAM OPTO SEMICONDUCTORS FOR AN ADVANCE WAIVER OF DOMESTIC AND FOREIGN INVENTION RIGHTS UNDER DOE CONTRACT NO. DE-FC26-05NT42341, SUBCONTRACT QZ001; W(A)-05-017, CH-1280 The Petitioner, OSRAM Opto Semiconductor (Osram) was awarded a subcontract under this cooperative agreement for the performance of work entitled, "Scaling Up KiloLumen Solid- State Lighting Exceeding 100 LPW via Remote Phosphor." The cooperative agreement was awarded to Light Prescriptions Innovators, LLC (LPI). The purpose of the cooperative agreement is to develop a new white light emitting diode (LED) light source that emits 1000 lumens with an efficacy exceeding 100 lumens per watt (LPW). The new white LED light source will use multiple

409

Synthesis and catalytic properties of metal and semiconductor nanoclusters  

SciTech Connect

Synthesis of metal or semiconductor nanoclusters in microheterogeneous oil-continuous inverse micelle systems is discussed. We focus on synthesis and catalytic properties of palladium, iron, and iron sulfide nanoclusters. Cluster size-control is achieved by changing the micelle size which is determined by small angle neutron scattering (SANS) and chosen to produce cluster in size range of 1-20 nm. Cluster sizes were determined by either transmission electron microscopy (TEM) or small-angle x-ray scattering (SAXS). Cluster structure was determined by either x-ray or electron diffraction. In the case of Fe nanoclusters the crystal structure depended on the chemical nature of the surfactant micelle used in the synthesis, illustrating the important role of the surfactant during the growth process. Results of in-situ pyrene hydrogenation using size-selected Pd clusters show a significant increase in activity/total surface area as the size decreases. These clusters also proved effective as unsupported catalysts for direct coal hydropyrolysis, even at very low metal concentrations. Synthesis and optical features of a new semiconductor cluster material, FeS{sub 2}, is discussed with regard to its use in photocatalysis. Application of FeS{sub 2} in coal hydrogenolysis reactions has improved yields of short chain hydrocarbons significantly compared to conventional FeS{sub 2} powders.

Wilcoxon, J.P.; Martino, T.; Klavetter, E.; Sylwester, A.P.

1993-08-01T23:59:59.000Z

410

Method and apparatus for thermal processing of semiconductor substrates  

DOE Patents (OSTI)

An improved apparatus and method for thermal processing of semiconductor wafers. The apparatus and method provide the temperature stability and uniformity of a conventional batch furnace as well as the processing speed and reduced time-at-temperature of a lamp-heated rapid thermal processor (RTP). Individual wafers are rapidly inserted into and withdrawn from a furnace cavity held at a nearly constant and isothermal temperature. The speeds of insertion and withdrawal are sufficiently large to limit thermal stresses and thereby reduce or prevent plastic deformation of the wafer as it enters and leaves the furnace. By processing the semiconductor wafer in a substantially isothermal cavity, the wafer temperature and spatial uniformity of the wafer temperature can be ensured by measuring and controlling only temperatures of the cavity walls. Further, peak power requirements are very small compared to lamp-heated RTPs because the cavity temperature is not cycled and the thermal mass of the cavity is relatively large. Increased speeds of insertion and/or removal may also be used with non-isothermal furnaces.

Griffiths, Stewart K. (Danville, CA); Nilson, Robert H. (Cardiss, CA); Mattson, Brad S. (Los Gatos, CA); Savas, Stephen E. (Alameda, CA)

2000-01-01T23:59:59.000Z

411

High-efficiency photovoltaics based on semiconductor nanostructures  

SciTech Connect

The objective of this project was to exploit a variety of semiconductor nanostructures, specifically semiconductor quantum wells, quantum dots, and nanowires, to achieve high power conversion efficiency in photovoltaic devices. In a thin-film device geometry, the objectives were to design, fabricate, and characterize quantum-well and quantum-dot solar cells in which scattering from metallic and/or dielectric nanostructures was employed to direct incident photons into lateral, optically confined paths within a thin (~1-3um or less) device structure. Fundamental issues concerning nonequilibrium carrier escape from quantum-confined structures, removal of thin-film devices from an epitaxial growth substrate, and coherent light trapping in thin-film photovoltaic devices were investigated. In a nanowire device geometry, the initial objectives were to engineer vertical nanowire arrays to optimize optical confinement within the nanowires, and to extend this approach to core-shell heterostructures to achieve broadspectrum absorption while maintaining high opencircuit voltages. Subsequent work extended this approach to include fabrication of nanowire photovoltaic structures on low-cost substrates.

Yu, Paul K.L. [University of California, San Diego; Yu, Edward T. [University of Texas at Austin; Wang, Deli [University of California, San Diego

2011-10-31T23:59:59.000Z

412

Helicon wave excitation to produce energetic electrons for manufacturing semiconductors  

DOE Patents (OSTI)

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

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

1998-10-20T23:59:59.000Z

413

Femtosecond laser interactions with semiconductor and dielectric materials  

SciTech Connect

Electronic excitation-relaxation processes induced by ultra-short laser pulses are studied numerically for semiconductors and dielectric materials (Si, quartz). A detailed kinetic approach is used in the calculations accounting for electron-photon-phonon, electron-phonon and electron-electron scatterings. In addition, both laser field ionization ranging from multi-photon to tunneling one, and electron impact (avalanche) ionization processes are included in the model. Based on the performed calculations we study the relaxation time as a function of laser parameters. It is shown that this time depends on the density of the created free carriers, which in turn is a nonlinear function of laser intensity. In addition, a simple damage criterion is proposed based on the mean electron energy density rather than on critical free electron density. This criterion gives a reasonable agreement with the available experimental data practically without adjustable parameters. Furthermore, the performed modeling provides energy absorbed in the target, conditions for damage of dielectric materials, as well as conditions for surface plasmon excitation and for periodic surface structure formation on the surface of semiconductor materials.

Shcheblanov, Nikita S.; Derrien, Thibault J. Y.; Itina, Tatiana E. [Laboratoire Hubert Curien, CNRS//Universite Jeann Monnet, 18 rue du Prof. Benoit Lauras, 42000 Saint-Etienne (France); Laboratoire Lasers, Plasmas et Procedes Photoniques, CNRS//Universite de la Mediterranee, 162 avenue de Luminy, 13288, Marseille (France); Laboratoire Hubert Curien, CNRS//Universite Jeann Monnet, 18 rue du Prof. Benoit Lauras, 42000 Saint-Etienne (France)

2012-07-30T23:59:59.000Z

414

Low-temperature magnetization of (Ga,Mn) As semiconductors  

E-Print Network (OSTI)

We report on a comprehensive study of the ferromagnetic moment per Mn atom in (Ga,Mn)As ferromagnetic semiconductors. Theoretical discussion is based on microscopic calculations and on an effective model of Mn local moments antiferromagnetically coupled to valence band hole spins. The validity of the effective model over the range of doping studied is assessed by comparing with microscopic tight-binding/coherent-potential approximation calculations. Using the virtual crystal k center dot p model for hole states, we evaluate the zero-temperature mean-field contributions to the magnetization from the hole kinetic and exchange energies, and magnetization suppression due to quantum fluctuations of Mn moment orientations around their mean-field ground state values. Experimental low-temperature ferromagnetic moments per Mn are obtained by superconducting quantum interference device and x-ray magnetic circular dichroism measurements in a series of (Ga,Mn)As semiconductors with nominal Mn doping ranging from similar to 2 to 8%. Hall measurements in as-grown and annealed samples are used to estimate the number of uncompensated substitutional Mn moments. Based on our comparison between experiment and theory we conclude that all these Mn moments in high quality (Ga,Mn)As materials have nearly parallel ground state alignment.

Jungwirth, T.; Masek, J.; Wang, KY; Edmonds, KW; Sawicki, M.; Polini, M.; Sinova, Jairo; MacDonald, AH; Campion, RP; Zhao, LX; Farley, NRS; Johal, TK; van der Laan, G.; Foxon, CT; Gallagher, BL.

2006-01-01T23:59:59.000Z

415

Characterization of Hydrogen Complex Formation in III-V Semiconductors  

DOE Green Energy (OSTI)

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.

Williams, Michael D.

2006-09-28T23:59:59.000Z

416

Spin-polarized current oscillations in diluted magnetic semiconductor multiple quantum wells Manuel Bejar,1  

E-Print Network (OSTI)

Spin-polarized current oscillations in diluted magnetic semiconductor multiple quantum wells Manuel and charge dynamics of electrons in n-doped II-VI semiconductor multiple quantum wells when one or more quantum wells are doped with Mn. The interplay between strongly nonlinear interwell charge transport

Sánchez, David

417

Performance of a parallel algebraic multilevel preconditioner for stabilized finite element semiconductor device modeling  

Science Conference Proceedings (OSTI)

In this study results are presented for the large-scale parallel performance of an algebraic multilevel preconditioner for solution of the drift-diffusion model for semiconductor devices. The preconditioner is the key numerical procedure determining ... Keywords: Drift-diffusion, Finite element, Graph partitioning, Multigrid, Multilevel preconditioners, Newton-Krylov, Nonsmoothed aggregation, Schwarz domain decomposition, Semiconductor devices

Paul T. Lin; John N. Shadid; Marzio Sala; Raymond S. Tuminaro; Gary L. Hennigan; Robert J. Hoekstra

2009-09-01T23:59:59.000Z

418

Using the FDM and ANP to construct a sustainability balanced scorecard for the semiconductor industry  

Science Conference Proceedings (OSTI)

This paper proposed a sustainability balanced scorecard (SBSC) framework to measure the sustainable performance of the semiconductor industry. Based on the principle of four perspectives of balanced scorecard (BSC), of which two were changed from the ... Keywords: Analytic network process, Fuzzy Delphi method, Semiconductor industry, Sustainability balanced scorecard

Chia-Wei Hsu; Allen H. Hu; Cherng-Ying Chiou; Ta-Che Chen

2011-09-01T23:59:59.000Z

419

Ultrafast shift and injection currents observed in wurtzite semiconductors via emitted terahertz radiation  

E-Print Network (OSTI)

and injection currents have been generated in bulk GaAs and strained GaAs quantum wells QWs , respectivelyUltrafast shift and injection currents observed in wurtzite semiconductors via emitted terahertz; published online 18 November 2005 Shift and injection currents are generated in the wurtzite semiconductors

Van Driel, Henry M.

420

Density-gradient theory: a macroscopic approach to quantum confinement and tunneling in semiconductor devices  

Science Conference Proceedings (OSTI)

Density-gradient theory provides a macroscopic approach to modeling quantum transport that is particularly well adapted to semiconductor device analysis and engineering. After some introductory observations, the basis of the theory in macroscopic and ... Keywords: Continuum, Density-gradient, Electron transport, Quantum confinement, Quantum tunneling, Semiconductor device simulation, Thermodynamics

M. G. Ancona

2011-06-01T23:59:59.000Z

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


421

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

DOE Patents (OSTI)

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.

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

1999-01-01T23:59:59.000Z

422

Spline regression based feature extraction for semiconductor process fault detection using support vector machine  

Science Conference Proceedings (OSTI)

Quality control is attracting more attention in semiconductor market due to harsh competition. This paper considers Fault Detection (FD), a well-known philosophy in quality control. Conventional methods, such as non-stationary SPC chart, PCA, PLS, and ... Keywords: Fault detection, Feature extraction, Semiconductor manufacturing, Spline regression, Support vector machine

Jonghyuck Park; Ick-Hyun Kwon; Sung-Shick Kim; Jun-Geol Baek

2011-05-01T23:59:59.000Z

423

Instrumentation and Control Strategies for Plant-Wide and Fleet-Wide Cost Reduction: Utility Application Guideline  

Science Conference Proceedings (OSTI)

This CD provides guidance from the EPRI initiative on IC Strategies for Plant-Wide and Fleet-Wide Cost Reduction. Included on the CD are EPRI Technical Report 1015087, Instrumentation and Control Strategies for Plant-Wide and Fleet-Wide Cost Reduction: Utility Application Guideline, published October 2007, and two multimedia briefings. The report and briefings describe a wide range of options while emphasizing integrated modernization across the plant or fleet. Coordinated improvements to shared communi...

2008-09-03T23:59:59.000Z

424

Argonne CNM News: State-of-the-Art Diamond Semiconductor Technology  

NLE Websites -- All DOE Office Websites (Extended Search)

State-of-the-Art Diamond Semiconductor Technology Licensed to AKHAN Technologies State-of-the-Art Diamond Semiconductor Technology Licensed to AKHAN Technologies The U.S. Department of Energy's Argonne National Laboratory announced today that the laboratory has granted AKHAN Technologies, Inc., exclusive diamond semiconductor application licensing rights to breakthrough low-temperature diamond deposition technology developed by Argonne's Center for Nanoscale Materials (CNM). The method allows for the deposition of nanocrystalline diamond on a variety of wafer substrate materials at temperatures as low as 400°C, highly advantageous for integration with processed semiconductor electronic materials and resulting in the deposition of low-defect nanocrystalline diamond (NCD) thin films. The combination of CNM's low-temperature diamond technology with the AKHAN Miraj Diamond(tm) process represents the state of the art in diamond semiconductor thin-film technology.

425

Chemical vapor deposition of amorphous semiconductor films. Semiannual report, 1 May 1984-31 October 1984  

DOE Green Energy (OSTI)

This report describes the results of research done by the Institute of Energy Conversion for the Solar Energy Research Institute in 1984 on high-efficiency, stable, amorphous silicon solar cells, fabricated by chemical vapor deposition (CVD) from disilane at high growth rates. The kinetics of CVD with higher order silanes were modelled for a tubular reactor with static substrates. A gas-phase reaction network was adopted, based on published silylene insertion and decomposition pathways. Mass balances for hydrogen and all saturated silanes through octasilane were derived. Boron-doped a-Si:H p-layers were deposited by CVD at 200/sup 0/ to 250/sup 0/C. Band gap and conductivity depended strongly on the diborane fraction in the feed gas, independent of substrate temperature. The effects of intrinsic layer deposition temperature and growth rate on material properties and device performance were studied. Cell parameters of p-i-n cells were correlated with i-layer deposition temperature and growth rate. Fill factor and short-circuit current depended on deposition conditions, while open-circuit voltage did not. Effects of diborane additions to the feed gas during i-layer deposition were studied. Experimental evidence and calculations indicate high resistance at the back contact.

Baron, B.N.; Rocheleau, R.E.; Hegedus, S.S.

1985-06-01T23:59:59.000Z

426

WorldWideScience.org: China's Participation Expands Access to...  

Office of Scientific and Technical Information (OSTI)

International Council for Scientific and Technical Information (ICSTI), which serves as a primary sponsor of the WorldWideScience Alliance. WorldWideScience.org was conceived and...

427

Wide electrochemical window solvents for use in electrochemical ...  

Wide electrochemical window solvents for use in electrochemical devices and electrolyte solutions incorporating such solvents United States Patent

428

FINITE DIFFERENCE METHODS FOR THE WIDE-ANGLE `PARABOLIC' EQUATION  

E-Print Network (OSTI)

FINITE DIFFERENCE METHODS FOR THE WIDE-ANGLE `PARABOLIC' EQUATION GEORGIOS AKRIVIS Abstract. We consider a model initial and boundary value problem for the wide-angle `parabolic' equation Lur = icu, the wide-angle `parabolic'equation of underwater acoustics. Given R > 0, µ 0, > 0, , and q real

Akrivis, Georgios

429

Transforming the Lighting Sector with Semiconductor Lighting Technologies  

NLE Websites -- All DOE Office Websites (Extended Search)

17-TED-000924-9/27 SR#2000-2333C 17-TED-000924-9/27 SR#2000-2333C Transforming the Lighting Sector With Semiconductor Lighting Technologies Thomas Drennen Sandia National Laboratories Roland Haitz Agilent Technologies Jeffrey Tsao E20 Communications Sandia National Laboratories USAEE/IAEE Annual Meetings Philadelphia, PA September 24-27, 2000 Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under Contract DE-AC04-94AL85000 2 6217-TED-000924-9/27 SR#2000-2333C Overview * Introduction * U.S. Lighting Demand * Evolution of LEDs * The LED Simulation Model (LEDSim) * Results 3 6217-TED-000924-9/27 SR#2000-2333C Introduction 0 50 100 150 200 1970 1980 1990 2000 2010 2020 Efficiency (lm/W) Year Incandescent Halogen Fluorescent Semi- conductor

430

GaN Metal Oxide Semiconductor Field Effect Transistors  

SciTech Connect

A GaN based depletion mode metal oxide semiconductor field effect transistor (MOSFET) was demonstrated using Ga{sub 2}O{sub 3}(Gd{sub 2}O{sub 3}) as the gate dielectric. The MOS gate reverse breakdown voltage was > 35V which was significantly improved from 17V of Pt Schottky gate on the same material. A maximum extrinsic transconductance of 15 mS/mm was obtained at V{sub ds} = 30 V and device performance was limited by the contact resistance. A unity current gain cut-off frequency, f{sub {tau}}, and maximum frequency of oscillation, f{sub max} of 3.1 and 10.3 GHz, respectively, were measured at V{sub ds} = 25 V and V{sub gs} = {minus}20 V.

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

1999-03-02T23:59:59.000Z

431

System for characterizing semiconductor materials and photovoltaic devices through calibration  

DOE Patents (OSTI)

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.

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

432

Improved Thermoelectric Devices: Advanced Semiconductor Materials for Thermoelectric Devices  

SciTech Connect

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.

None

2009-12-11T23:59:59.000Z

433

Band engineering in dilute nitride and bismide semiconductor lasers  

E-Print Network (OSTI)

Highly mismatched semiconductor alloys such as GaNAs and GaBiAs have several novel electronic properties, including a rapid reduction in energy gap with increasing x and also, for GaBiAs, a strong increase in spin orbit- splitting energy with increasing Bi composition. We review here the electronic structure of such alloys and their consequences for ideal lasers. We then describe the substantial progress made in the demonstration of actual GaInNAs telecomm lasers. These have characteristics comparable to conventional InP-based devices. This includes a strong Auger contribution to the threshold current. We show, however, that the large spin-orbit-splitting energy in GaBiAs and GaBiNAs could lead to the suppression of the dominant Auger recombination loss mechanism, finally opening the route to e?fficient temperature-stable telecomm and longer wavelength lasers with significantly reduced power consumption.

Christopher A. Broderick; Muhammad Usman; Stephen J. Sweeney; Eoin P. O'Reilly

2012-08-31T23:59:59.000Z

434

High gain photoconductive semiconductor switch having tailored doping profile zones  

SciTech Connect

A photoconductive semiconductor switch with tailored doping profile zones beneath and extending laterally from the electrical contacts to the device. The zones are of sufficient depth and lateral extent to isolate the contacts from damage caused by the high current filaments that are created in the device when it is turned on. The zones may be formed by etching depressions into the substrate, then conducting epitaxial regrowth in the depressions with material of the desired doping profile. They may be formed by surface epitaxy. They may also be formed by deep diffusion processes. The zones act to reduce the energy density at the contacts by suppressing collective impact ionization and formation of filaments near the contact and by reducing current intensity at the contact through enhanced current spreading within the zones.

Baca, Albert G. (Albuquerque, NM); Loubriel, Guillermo M. (Albuquerque, NM); Mar, Alan (Albuquerque, NM); Zutavern, Fred J (Albuquerque, NM); Hjalmarson, Harold P. (Albuquerque, NM); Allerman, Andrew A. (Albuquerque, NM); Zipperian, Thomas E. (Edgewood, NM); O' Malley, Martin W. (Edgewood, NM); Helgeson, Wesley D. (Albuquerque, NM); Denison, Gary J. (Sandia Park, NM); Brown, Darwin J. (Albuquerque, NM); Sullivan, Charles T. (Albuquerque, NM); Hou, Hong Q. (Albuquerque, NM)

2001-01-01T23:59:59.000Z

435

System for characterizing semiconductor materials and photovoltaic devices through calibration  

DOE Patents (OSTI)

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.

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

1998-05-26T23:59:59.000Z

436

Predicted Ultrafast Single Qubit Operations in Semiconductor Quantum Dots  

E-Print Network (OSTI)

Several recently proposed implementations of scalable quantum computation rely on the ability to manipulate the spin polarization of individual electrons in semiconductors. The most rapid single-spin-manipulation technique to date relies on the generation of an effective magnetic field via a spin-sensitive optical Stark effect. This approach has been used to split spin states in colloidal CdSe quantum dots and to manipulate ensembles of spins in ZnMnSe quantum wells with femtosecond optical pulses. Here we report that the process will produce a coherent rotation of spin in quantum dots containing a single electron. The calculated magnitude of the effective magnetic field depends on the dot bandgap and the strain. We predict that in InAs/InP dots, for reasonable experimental parameters, the magnitude of the rotation is sufficient and the intrinsic error is low enough for them to serve as elements of a quantum dot based quantum computer.

C. E. Pryor; M. E. Flatté

2002-11-25T23:59:59.000Z

437

Active RF Pulse Compression Using An Electrically Controlled Semiconductor Switch  

SciTech Connect

First we review the theory of active pulse compression systems using resonant delay lines. Then we describe the design of an electrically controlled semiconductor active switch. The switch comprises an active window and an overmoded waveguide three-port network. The active window is based on a four-inch silicon wafer which has 960 PIN diodes. These are spatially combined in an overmoded waveguide. We describe the philosophy and design methodology for the three-port network and the active window. We then present the results of using this device to compress 11.4 GHz RF signals with high compression ratios. We show how the system can be used with amplifier like sources, in which one can change the phase of the source by manipulating the input to the source. We also show how the active switch can be used to compress a pulse from an oscillator like sources, which is not possible with passive pulse compression systems.

Guo, Jiquan; Tantawi, Sami; /SLAC

2007-01-10T23:59:59.000Z

438

Subtle Chemistry of Colloidal, Quantum-Confined Semiconductor Nanostructures  

SciTech Connect

Nanoscale colloidal semiconductor structures with at least one dimension small enough to experience quantum confinement effects have captured the imagination and attention of scientists interested in controlling various chemical and photophysical processes. Aside from having desirable quantum confinement properties, colloidal nanocrystals are attractive because they are often synthesized in low-temperature, low-cost, and potentially scalable manners using simple benchtop reaction baths. Considerable progress in producing a variety of shapes, compositions, and complex structures has been achieved. However, there are challenges to overcome in order for these novel materials to reach their full potential and become new drivers for commercial applications. The final shape, composition, nanocrystal-ligand structure, and size can depend on a delicate interplay of precursors, surface ligands, and other compounds that may or may not participate in the reaction. In this Perspective, we discuss current efforts toward better understanding how the reactivity of the reagents can be used to produce unique and complex nanostructures.

Hughes, B. K.; Luther, J. M.; Beard, M. C.

2012-06-26T23:59:59.000Z

439

Standard practice for radiologic examination of semiconductors and electronic components  

E-Print Network (OSTI)

1.1 This practice provides the minimum requirements for nondestructive radiologic examination of semiconductor devices, microelectronic devices, electromagnetic devices, electronic and electrical devices, and the materials used for construction of these items. 1.2 This practice covers the radiologic examination of these items to detect possible defective conditions within the sealed case, especially those resulting from sealing the lid to the case, and internal defects such as extraneous material (foreign objects), improper interconnecting wires, voids in the die attach material or in the glass (when sealing glass is used) or physical damage. 1.3 The values stated in inch-pound units are to be regarded as standard. No other units of measurement are included in this practice. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the app...

American Society for Testing and Materials. Philadelphia

2009-01-01T23:59:59.000Z

440

The development of large area saturable Bragg reflectors for the generation of widely-tunable ultra-short pulses  

E-Print Network (OSTI)

This thesis focuses on the realization of two photonic devices; 1) semiconductor lasers and 2) large area broadband Saturable Bragg Reflectors (SBRs). Semiconductor lasers explore the use of 3D and 2D quantum confinement ...

Nabanja, Sheila P

2012-01-01T23:59:59.000Z

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


441

Benefits of Site-wide NEPA Review | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Benefits of Site-wide NEPA Review Benefits of Site-wide NEPA Review Benefits of Site-wide NEPA Review The purpose of this guidance memorandum is to describe potential benefits of conducting a site-wide NEPA review (environmental impact statement or environmental assessment). I believe that this information will help program and field offices prepare their annual NEPA planning summaries and their overall NEPA compliance strategies. Site-wide reviews can aid the Department of Energy (DOE) in meeting its goals to streamline the NEPA process, to make that process more useful to decision makers and the public, and to reduce the time and cost required to prepare NEPA documents Benefits of Site-wide NEPA Review More Documents & Publications Benefits of Site-wide NEPA National Environmental Policy Act Review (1994)

442

Interconnection-Wide Transmission Planning Initiative: Topic A,  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Interconnection-Wide Transmission Planning Initiative: Topic A, Interconnection-Wide Transmission Planning Initiative: Topic A, Interconnection-Level Analysis and Planning Interconnection-Wide Transmission Planning Initiative: Topic A, Interconnection-Level Analysis and Planning A description of the requirements for Topic A for all Interconnections under the Interconnection-Wide Transmission Planning Initiative, part of the American Recovery and Reinvestment Act. Interconnection-Wide Transmission Planning Initiative: Topic A, Interconnection-Level Analysis and Planning More Documents & Publications Microsoft Word - yDE-FOA-0000068.rtf Interconnection-Wide Transmission Planning Initiative: Topic B, Cooperation Among States in the Eastern Interconnection on Electric Resource Planning and Priorities Interconnection-Wide Transmission Planning Initiative: Topic B, Cooperation

443

Methods of forming semiconductor devices and devices formed using such methods  

SciTech Connect

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.

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

2013-05-21T23:59:59.000Z

444

Understanding How Semiconductors Absorb Light | U.S. DOE Office of Science  

NLE Websites -- All DOE Office Websites (Extended Search)

How Semiconductors Absorb Light How Semiconductors Absorb Light Advanced Scientific Computing Research (ASCR) ASCR Home About Research Facilities Science Highlights Benefits of ASCR Funding Opportunities Advanced Scientific Computing Advisory Committee (ASCAC) News & Resources Contact Information Advanced Scientific Computing Research U.S. Department of Energy SC-21/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-7486 F: (301) 903-4846 E: sc.ascr@science.doe.gov More Information » March 2013 Understanding How Semiconductors Absorb Light Advances in how we calculate optical properties of semiconductors shorten the path to improved solar cells and other optoelectronic devices. Print Text Size: A A A Subscribe FeedbackShare Page Click to enlarge photo. Enlarge Photo

445

Multivariable analysis of spectral measurements for the characterization of semiconductor processes  

E-Print Network (OSTI)

The availability of affordable and reliable optical sensor technology and the abundance of data that these sensors now provide have created new opportunities to better characterize and control semiconductor processes in ...

White, David A. (David Allan), 1966-

2001-01-01T23:59:59.000Z

446

Prediction of semiconductor band edge positions in aqueous environments from first principles  

E-Print Network (OSTI)

The ability to predict a semiconductor's band edge positions in solution is important for the design of water-splitting photocatalyst materials. In this paper, we introduce a first-principles method to compute the ...

Wu, Yabi

447

Semiconductor-based all-optical switching for optical time-division multiplexed networks  

E-Print Network (OSTI)

All-optical switching will likely be required for future optical networks operating at data rates which exceed electronic processing speeds. Switches utilizing nonlinearities in semiconductor optical amplifiers (SOA) are ...

Robinson, Bryan S. (Bryan Shawn), 1975-

2003-01-01T23:59:59.000Z

448

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

E-Print Network (OSTI)

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 ...

Jifeng, Liu

449

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

E-Print Network (OSTI)

· Continuously mixed Light Source · T5 8 watt florescent bulbs · "Daylight Spectrum" · Color Rendering Index 75Photocatalytic Oxidation of Aqueous Organic Contaminants by Semiconductors using Visible Light

Meyers, Steven D.

450

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

E-Print Network (OSTI)

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 ...

Jadhav, Priyadarshani

2012-01-01T23:59:59.000Z

451

Spectroscopy and external control of optical dynamics in single semiconductor nanocrystals  

E-Print Network (OSTI)

Single molecule spectroscopy has progressed substantially in the past ten years and the accompanying progress in the optical study of single semiconductor nanocrystals has opened a new dimension in our understanding of the ...

Shimizu, Kentaro, 1975-

2002-01-01T23:59:59.000Z

452

Development of New Building Blocks for Constructing Novel Polymer Semiconductors for Organic Thin Film Transistors.  

E-Print Network (OSTI)

??Organic semiconductors are envisioned to have widespread applications in flexible displays, radio-frequency identification (RFID) tags, bio- and chem-sensors, as well as organic solar cells. Polymer… (more)

Yan, Zhuangqing

2013-01-01T23:59:59.000Z

453

Optical Probe for Semiconductor: Cooperative Research and Development Final Report, CRADA Number CRD-06-206  

DOE Green Energy (OSTI)

This CRADA involves development of a new semiconductor characterization tool, Optical Probe, which can be commercialized by GT Solar. GT Solar will participate in the design and testing of this instrument that will be developed under an IPP project.

Sopori, B.

2011-02-01T23:59:59.000Z

454

Role of propagating ionisation fronts in semiconductor generation of sub-ps THz radiation  

E-Print Network (OSTI)

in standard semiconductor THz emitters may lead to identification of superior materials and excitation) 2806. [7] J.L. Oudar, D. Hulin, A. Migus, A. Antonetti, F. Alexandre, Phys. Rev. Lett. 55 (1985) 2074

Strathclyde, University of

455

Atomic-scale properties of semiconductor heterostructures probed by scanning tunneling microscopy  

SciTech Connect

The engineering of advanced semiconductor heterostructure materials and devices requires a detailed understanding of, and control over, the structure and properties of semiconductor materials and devices at the atomic to nanometer scale. Cross-sectional scanning tunneling microscopy has emerged as a unique and powerful method to characterize structural morphology and electronic properties in semiconductor epitaxial layers and device structures at these length scales. The basic experimental techniques in cross-sectional scanning tunneling microscopy are described, and some representative applications to semiconductor heterostructure characterization drawn from recent investigations in the authors laboratory are discussed. Specifically, they describe some recent studies of InP/InAsP and InAsP/InAsSb heterostructures in which nanoscale compositional clustering has been observed and analyzed.

Yu, E.T.; Zuo, S.L.; Bi, W.G.; Tu, C.W. [Univ. of California, San Diego, La Jolla, CA (United States). Dept. of Electrical and Computer Engineering; Biefeld, R.M.; Allerman, A.A. [Sandia National Labs., Albuquerque, NM (United States)

1998-05-01T23:59:59.000Z

456

Program management systems for the semiconductor processing capital equipment supply chain  

E-Print Network (OSTI)

The Capital Equipment Procurement group of Intel Corporation is responsible for developing and procuring the semiconductor processing capital equipment that is used throughout all of the company's development and manufacturing ...

Chandler, Thomas B. (Thomas Brian), 1970-

2004-01-01T23:59:59.000Z

457

Colloidal semiconductor nanocrystals as nanoscale emissive probes in light emitting diodes and cell biology  

E-Print Network (OSTI)

This thesis employs colloidal semiconductor nanocrystals (NCs) as nanoscale emissive probes to investigate the physics of light emitting diodes (LEDs), as well as to unveil properties of cells that conventional imaging ...

Huang, Hao, Ph. D. Massachusetts Institute of Technology

2008-01-01T23:59:59.000Z

458

Product strategy in response to technological innovation in the semiconductor test industry  

E-Print Network (OSTI)

After the market boom of 2000 in the semiconductor industry changed significantly. The changes included stricter limits on capital cost spending, and the increased propensity of the industry to outsource the manufacturing ...

Lin, Robert W. (Robert Wei-Pang), 1976-

2004-01-01T23:59:59.000Z

459

X-ray and photoelectron spectroscopy of the structure, reactivity, and electronic structure of semiconductor nanocrystals  

E-Print Network (OSTI)

Figure 2-5 FESEM of 60Ĺ CdSe nanocrystals on hexanedithiol/properties of semiconductor (CdSe, InAs) nanocrystals andCdSe)..

Hamad, Kimberly S.

2000-01-01T23:59:59.000Z

460

Dilute magnetic semiconductor Cu2FeSnS4 nanocrystals with a novel zincblende structure  

Science Conference Proceedings (OSTI)

Diluted magnetic semiconductor Cu2FeSnS4 nanocrystals with a novel zincblende structure have been successfully synthesized by a hot-injection approach. Cu+, Fe2+, and Sn4+ ions occupy the same position in the ...

Xiaolu Liang; Xianhua Wei; Daocheng Pan

2012-01-01T23:59:59.000Z

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


461

The physics and chemistry of semiconductor nanocrystals in sol-gel derived optical microcavities  

E-Print Network (OSTI)

The incorporation of semiconductor nanocrystals (NCs) into sol-gel derived matrices presents both novel applications as well as a robust platform in which to investigate the nonlinear optical properties of NCs. This thesis ...

Chan, Yinthai

2006-01-01T23:59:59.000Z

462

Physics and simulation of transport processes in hybrid organic semiconductor devices  

E-Print Network (OSTI)

Organic semiconductors and nanomaterials promise to potentially form the basis for future efficient and cost-effective large area optoelectronic devices, such as lightemitting diodes and solar cells. Although these materials' ...

Rousseau, Ian Michael

2010-01-01T23:59:59.000Z

463

Dilute III-V Nitride Semiconductors and Material Systems: Physics and Technology, 1st edition  

Science Conference Proceedings (OSTI)

A major current challenge for semiconductor devices is to develop materials for the next generation of optical communication systems and solar power conversion applications. Recently, extensive research has revealed that an introduction of only a few ...

Ayse Erol; Ayse Erol

2008-03-01T23:59:59.000Z

464

Semiconductor with protective surface coating and method of manufacture thereof. [Patent application  

DOE Patents (OSTI)

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.

Hansen, W.L.; Haller, E.E.

1980-09-19T23:59:59.000Z

465

Simple method for surface selective adsorption of semiconductor nanocrystals with nanometric resolution  

Science Conference Proceedings (OSTI)

Self-assembly methods play a major role in many modern fabrication techniques for various nanotechnology applications. In this paper we demonstrate two alternatives for self-assembled patterning within the nanoscale resolution of optically active semiconductor ...

O. Koslovsky, S. Yochelis, N. Livneh, M. G. Harats, R. Rapaport, Y. Paltiel

2012-01-01T23:59:59.000Z

466

Growth of coincident site lattice matched semiconductor layers and devices on crystalline substrates  

DOE Patents (OSTI)

Methods of fabricating a semiconductor layer or device and said devices are disclosed. The methods include but are not limited to providing a substrate having a crystalline surface with a known lattice parameter (a). The method further includes growing a crystalline semiconductor layer on the crystalline substrate surface by coincident site lattice matched epitaxy, without any buffer layer between the crystalline semiconductor layer and the crystalline surface of the substrate. The crystalline semiconductor layer will be prepared to have a lattice parameter (a') that is related to the substrate lattice parameter (a). The lattice parameter (a') maybe related to the lattice parameter (a) by a scaling factor derived from a geometric relationship between the respective crystal lattices.

Norman, Andrew G; Ptak, Aaron J

2013-08-13T23:59:59.000Z

467

Electronic Properties of Disordered Organic Semiconductors via QM/MM Simulations  

E-Print Network (OSTI)

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, ...

Difley, Seth

468

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

E-Print Network (OSTI)

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, ...

Branham, Matthew S

2008-01-01T23:59:59.000Z

469

Substrate engineering for monolithic integration of III-V semiconductors with Si CMOS technology  

E-Print Network (OSTI)

Ge virtual substrates, fabricated using Si1-xGex-.Ge, compositionally graded buffers, enable the epitaxial growth of device-quality GaAs on Si substrates, but monolithic integration of III-V semiconductors with Si CMOS ...

Dohrman, Carl Lawrence

2008-01-01T23:59:59.000Z

470

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

E-Print Network (OSTI)

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 ...

Subbarao, Samuel P.

471

Integer programming-based real-time scheduler in semiconductor manufacturing  

Science Conference Proceedings (OSTI)

This paper demonstrates how an integer programming-based real-time scheduling heuristic approach can be applied for semiconductor manufacturing. Two integer programming formulations of a simplified version of this problem are proposed to model (1) a ...

Myoungsoo Ham; Young Hoon Lee; John W. Fowler

2009-12-01T23:59:59.000Z

472

Microwave frequency division and multiplication using an optically injected semiconductor laser  

E-Print Network (OSTI)

Senior Member of the IEEE Laser and Electro-Optics Society,modelocked semiconductor lasers,” Electron. Lett. , vol. 36,recovery by a ?ber ring laser employing a linear optical

Chan, Sze-Chun; Liu, Jia-Ming

2005-01-01T23:59:59.000Z

473

Application of RFID on equipment parts readiness management system of semiconductor packaging plant  

Science Conference Proceedings (OSTI)

Management of equipment parts readiness for process setup adjustment to meet variable order requirements in a semiconductor packaging plant is crucial to the health of production lines and downtime avoidance. In order to improve the current equipment ...

Wei-Ling Wang; Chiao-Tzu Huang; Shu-Jen Wang; Chia-Pao Chang; Hui-Wen Liao

2013-01-01T23:59:59.000Z

474

Media Advisory: Site-wide Safety Standards | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Media Advisory: Site-wide Safety Standards Media Advisory: Site-wide Safety Standards Media Advisory: Site-wide Safety Standards August 1, 2012 - 12:00pm Addthis Media Contacts Michael Turner, MSA michael_j_turner@rl.gov 509-376-2872 What: Department of Energy to announce two additions to the Hanford Site-wide Safety Standards - a set of 14 areas where Hanford contractors have collaborated to establish one uniform standard to guide safe operations. The latest additions to the Site-wide Safety Standards are Fall Protection and Electrical Safety. DOE Hanford management will explain the significance of the Site-wide Safety Standards, their use and application at the Hanford Site, the benefits to workers and the example Hanford is setting for excellence in safety. Media will then be offered a demonstration of Fall Protection training, along with other training programs at the DOE's Volpentest HAMMER Training Center, operated by Mission Support Alliance.

475

Executive Order 13583, Establishing a Coordinated Government-Wide  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Executive Order 13583, Establishing a Coordinated Government-Wide Executive Order 13583, Establishing a Coordinated Government-Wide Initiative to Promote Diversity and Inclusion in the Federal Workforce Executive Order 13583, Establishing a Coordinated Government-Wide Initiative to Promote Diversity and Inclusion in the Federal Workforce August 18, 2011 - 11:15am Addthis Executive Order 13583 Established a "coordinated government-wide initiative to promote diversity and inclusion in the federal workforce". Wherever possible, the Federal Government must also seek to consolidate compliance efforts established through related or overlapping statutory mandates, directions from Executive Orders, and regulatory requirements. Addthis Related Articles A Government-Wide Approach to a Diverse Workforce Executive Order 13583, Establishing a Coordinated Government-Wide Initiative to Promote Diversity and Inclusion in the Federal Workforce

476

Definition: Wide Area Monitoring, Visualization, & Control | Open Energy  

Open Energy Info (EERE)

Wide Area Monitoring, Visualization, & Control Wide Area Monitoring, Visualization, & Control Jump to: navigation, search Dictionary.png Wide Area Monitoring, Visualization, & Control Wide area monitoring and visualization requires time synchronized sensors, communications, and information processing that make it possible for the condition of the bulk power system to be observed and understood in real-time so that protective, preventative, or corrective action can be taken.[1] Related Terms Wide area, bes emergency, sustainability, smart grid References ↑ SmartGrid.gov 'Description of Functions' An inl LikeLike UnlikeLike You like this.Sign Up to see what your friends like. ine Glossary Definition Retrieved from "http://en.openei.org/w/index.php?title=Definition:Wide_Area_Monitoring,_Visualization,_%26_Control&oldid=502579

477

An iterative method for single and vertically stacked semiconductor quantum dots simulation  

Science Conference Proceedings (OSTI)

We present in this paper a computational effective nonlinear iterative method for calculating the electron energy spectra in single and vertically stacked InAs/GaAs semiconductor quantum dots. The physical model problem is formulated with the effective ... Keywords: Coupling effect, Electronic structure, Energy spectra, Modelling and simulation, Multishift QR method, Nonlinear eigenvalue problem, Semiconductor nanostructure, Single quantum dot, Vertically stacked quantum dot, Wave function

Yiming Li

2005-10-01T23:59:59.000Z

478

Method for making graded I-III-VI.sub.2 semiconductors and solar cell obtained thereby  

DOE Patents (OSTI)

Improved cell photovoltaic conversion efficiencies are obtained by the simultaneous elemental reactive evaporation process of Mickelsen and Chen for making semiconductors by closer control of the evaporation rates and substrate temperature during formation of the near contact, bulk, and near junction regions of a graded I-III-VI.sub.2, thin film, semiconductor, such as CuInSe.sub.2 /(Zn,Cd)S or another I-III-VI.sub.2 /II-VI heterojunction.

Devaney, Walter E. (Seattle, WA)

1987-08-04T23:59:59.000Z

479