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1

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

2

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

3

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

4

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...

5

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

6

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

7

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

8

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...

9

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

10

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

11

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

12

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

13

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

14

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

15

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

16

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

17

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.

18

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

19

Bilayer Graphene Gets a Bandgap  

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

Bilayer Graphene Gets a Bandgap Bilayer Graphene Gets a Bandgap Bilayer Graphene Gets a Bandgap Print Wednesday, 26 August 2009 00:00 Graphene is the two-dimensional crystalline form of carbon whose extraordinary electron mobility and other unique features hold great promise for nanoscale electronics and photonics. But without a bandgap, graphene's promise can't be realized. As with monolayer graphene, bilayer graphene also has a zero bandgap and thus behaves like a metal. But a bandgap can be introduced if an electric displacement field is applied to the two layers; the material then behaves like a semiconductor. A team of researchers from Berkeley has engineered a bandgap in bilayer graphene that can be precisely controlled from 0 to 250 meV. With precision control of its bandgap over a wide range, plus independent manipulation of its electronic states through electrical doping, dual-gated bilayer graphene becomes a remarkably flexible tool for nanoscale electronic devices.

20

Bilayer Graphene Gets a Bandgap  

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

Bilayer Graphene Gets a Bandgap Bilayer Graphene Gets a Bandgap Bilayer Graphene Gets a Bandgap Print Wednesday, 26 August 2009 00:00 Graphene is the two-dimensional crystalline form of carbon whose extraordinary electron mobility and other unique features hold great promise for nanoscale electronics and photonics. But without a bandgap, graphene's promise can't be realized. As with monolayer graphene, bilayer graphene also has a zero bandgap and thus behaves like a metal. But a bandgap can be introduced if an electric displacement field is applied to the two layers; the material then behaves like a semiconductor. A team of researchers from Berkeley has engineered a bandgap in bilayer graphene that can be precisely controlled from 0 to 250 meV. With precision control of its bandgap over a wide range, plus independent manipulation of its electronic states through electrical doping, dual-gated bilayer graphene becomes a remarkably flexible tool for nanoscale electronic devices.

Note: This page contains sample records for the topic "wide bandgap 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

Bilayer Graphene Gets a Bandgap  

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

Bilayer Graphene Gets a Bandgap Print Bilayer Graphene Gets a Bandgap Print Graphene is the two-dimensional crystalline form of carbon whose extraordinary electron mobility and other unique features hold great promise for nanoscale electronics and photonics. But without a bandgap, graphene's promise can't be realized. As with monolayer graphene, bilayer graphene also has a zero bandgap and thus behaves like a metal. But a bandgap can be introduced if an electric displacement field is applied to the two layers; the material then behaves like a semiconductor. A team of researchers from Berkeley has engineered a bandgap in bilayer graphene that can be precisely controlled from 0 to 250 meV. With precision control of its bandgap over a wide range, plus independent manipulation of its electronic states through electrical doping, dual-gated bilayer graphene becomes a remarkably flexible tool for nanoscale electronic devices.

22

Bilayer Graphene Gets a Bandgap  

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

Bilayer Graphene Gets a Bandgap Print Bilayer Graphene Gets a Bandgap Print Graphene is the two-dimensional crystalline form of carbon whose extraordinary electron mobility and other unique features hold great promise for nanoscale electronics and photonics. But without a bandgap, graphene's promise can't be realized. As with monolayer graphene, bilayer graphene also has a zero bandgap and thus behaves like a metal. But a bandgap can be introduced if an electric displacement field is applied to the two layers; the material then behaves like a semiconductor. A team of researchers from Berkeley has engineered a bandgap in bilayer graphene that can be precisely controlled from 0 to 250 meV. With precision control of its bandgap over a wide range, plus independent manipulation of its electronic states through electrical doping, dual-gated bilayer graphene becomes a remarkably flexible tool for nanoscale electronic devices.

23

Bilayer Graphene Gets a Bandgap  

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

Bilayer Graphene Gets a Bandgap Print Bilayer Graphene Gets a Bandgap Print Graphene is the two-dimensional crystalline form of carbon whose extraordinary electron mobility and other unique features hold great promise for nanoscale electronics and photonics. But without a bandgap, graphene's promise can't be realized. As with monolayer graphene, bilayer graphene also has a zero bandgap and thus behaves like a metal. But a bandgap can be introduced if an electric displacement field is applied to the two layers; the material then behaves like a semiconductor. A team of researchers from Berkeley has engineered a bandgap in bilayer graphene that can be precisely controlled from 0 to 250 meV. With precision control of its bandgap over a wide range, plus independent manipulation of its electronic states through electrical doping, dual-gated bilayer graphene becomes a remarkably flexible tool for nanoscale electronic devices.

24

Bilayer Graphene Gets a Bandgap  

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

Bilayer Graphene Gets a Bandgap Print Bilayer Graphene Gets a Bandgap Print Graphene is the two-dimensional crystalline form of carbon whose extraordinary electron mobility and other unique features hold great promise for nanoscale electronics and photonics. But without a bandgap, graphene's promise can't be realized. As with monolayer graphene, bilayer graphene also has a zero bandgap and thus behaves like a metal. But a bandgap can be introduced if an electric displacement field is applied to the two layers; the material then behaves like a semiconductor. A team of researchers from Berkeley has engineered a bandgap in bilayer graphene that can be precisely controlled from 0 to 250 meV. With precision control of its bandgap over a wide range, plus independent manipulation of its electronic states through electrical doping, dual-gated bilayer graphene becomes a remarkably flexible tool for nanoscale electronic devices.

25

Novel Approaches to Wide Bandgap CuInSe2 Based Absorbers  

SciTech Connect

This project targeted the development of high performance wide bandgap solar cells based on thin film alloys of CuInSe2 to relax constraints on module design and enable tandem solar cell structures. This addressed goals of the Solar Energy Technologies Program for Next Generation PV to develop technology needed for higher thin film module efficiency as a means to reduce costs. Specific objectives of the research project were: 1) to develop the processes and materials required to improve the performance of wide bandgap thin film solar cells based on alloys of CuInSe2, and 2) to provide the fundamental science and engineering basis for the material, electronic, and device properties required to effectively apply these processes and materials to commercial manufacture. CuInSe2-based photovoltaics have established the highest efficiencies of the thin film materials at both the cell and module scales and are actively being scaled up to commercialization. In the highest efficiency cells and modules, the optical bandgap, a function of the CuInSe2-based alloy composition, is relatively low compared to the optimum match to the solar spectrum. Wider bandgap alloys of CuInSe2 produce higher cell voltages which can improve module performance and enable the development of tandem solar cells to boost the overall efficiency. A focus for the project was alloying with silver to form (AgCu)(InGa)Se2 pentenary thin films deposited by elemental co-evaporation which gives the broadest range of control of composition and material properties. This alloy has a lower melting temperature than Ag-free, Cu-based chalcopyrite compounds, which may enable films to be formed with lower defect densities and the (AgCu)(InGa)Se2 films give improved material properties and better device performance with increasing bandgap. A comprehensive characterization of optical, structural, and electronic properties of (AgCu)(InGa)Se2 was completed over the complete compositional range 0 ? Ga/(In+Ga) ? 1 and 0 ? Ag/(Ag+Cu) ? 1. Evidence of improved material quality includes reduced sub-bandgap optical absorption, sharper bandtails, and increased grain size with Ag addition. The Ag alloying was shown to increase the range of bandgaps over which solar cells can be fabricated without any drop-off in performance. With bandgap greater than 1.6 eV, in the range needed for tandem solar cells, (AgCu)(InGa)Se2 gave higher efficiency than other CuInSe2-based alloys. Using a simple single-stage co-evaporation process, a solar cell with 17.6% efficiency using a film with bandgap = 1.3 eV was achieved, demonstrating the viability of (AgCu)(InGa)Se2 for high efficiency devices. With a three-stage co-evaporation process for (AgCu)(InGa)Se2 deposition a device with efficiency = 13.0 % and VOC = 890 mV with JSC = 20.5 mA/cm2, FF = 71.3% was achieved. This surpasses the performance of other wide bandgap CuInSe2-based solar cells. Detailed characterization of the electronic properties of the materials and devices including the application of advanced admittance-based easements was completed.

William N. Shafarman

2011-04-28T23:59:59.000Z

26

NREL Produces Highly Efficient, Wide-Bandgap, Thin-Film Solar Cells (Fact Sheet)  

Science Conference Proceedings (OSTI)

Researchers at the National Renewable Energy Laboratory (NREL) are finding new ways to manufacture thin-film solar cells made from copper, indium, gallium, and selenium - called CIGS cells - that are different than conventional CIGS solar cells. Their use of high-temperature glass, designed by SCHOTT AG, allows higher fabrication temperatures, opening the door to new CIGS solar cells employing light-absorbing materials with wide 'bandgaps.'

Not Available

2012-09-01T23:59:59.000Z

27

Improved Energy Conversion Efficiency in Wide-Bandgap Cu(In,Ga)Se2 Solar Cells: Preprint  

DOE Green Energy (OSTI)

This report outlines improvements to the energy conversion efficiency in wide bandgap (Eg>1.2 eV) solar cells based on CuIn1-xGaxSe2. Using (a) alkaline containing high temperature glass substrates, (b) elevated substrate temperatures 600?C-650?C and (c) high vacuum evaporation from elemental sources following NREL's three-stage process, we have been able to improve the performance of wider bandgap solar cells with 1.218% for absorber bandgaps ~1.30 eV and efficiencies ~16% for bandgaps up to ~1.45 eV. In comparing J-V parameters in similar materials, we establish gains in the open-circuit voltage and, to a lesser degree, the fill factor value, as the reason for the improved performance. The higher voltages seen in these wide gap materials grown at high substrate temperatures may be due to reduced recombination at the grain boundary of such absorber films. Solar cell results, absorber materials characterization, and experimental details are reported.

Contreras, M.; Mansfield, L.; Egaas, B.; Li, J.; Romero, M.; Noufi, R.; Rudiger-Voigt, E.; Mannstadt, W.

2011-07-01T23:59:59.000Z

28

NREL Produces Highly Efficient, Wide-Bandgap, Thin-Film Solar...  

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

Low-bandgap cells can lose 25% of their power output and efficiency ratings as solar cell operating temperatures climb to 75C or more, a common occurrence in hot and arid...

29

Optical Determination of Gate--Tunable Bandgap in Bilayer Graphene  

Science Conference Proceedings (OSTI)

The electronic bandgap is an intrinsic property of semiconductors and insulators that largely determines their transport and optical properties. As such, it has a central role in modern device physics and technology and governs the operation of semiconductor devices such as p-n junctions, transistors, photodiodes and lasers. A tunable bandgap would be highly desirable because it would allow great flexibility in design and optimization of such devices, in particular if it could be tuned by applying a variable external electric field. However, in conventional materials, the bandgap is fixed by their crystalline structure, preventing such bandgap control. Here we demonstrate the realization of a widely tunable electronic bandgap in electrically gated bilayer graphene. Using a dual-gate bilayer graphene field-effect transistor (FET) and infrared microspectroscopy, we demonstrate a gate-controlled, continuously tunable bandgap of up to 250 meV. Our technique avoids uncontrolled chemical doping and provides direct evidence of a widely tunable bandgap -- spanning a spectral range from zero to mid-infrared -- that has eluded previous attempts. Combined with the remarkable electrical transport properties of such systems, this electrostatic bandgap control suggests novel nanoelectronic and nanophotonic device applications based on graphene.

Zhang, Yuanbo; Tang, Tsung-Ta; Girit, Caglar; Hao, Zhao; Martin, Michael C.; Zettl, Alex; Crommie, Michael F.; Shen, Y. Ron; Wang, Feng

2009-08-11T23:59:59.000Z

30

Development of a Wide Bandgap Cell for Thin Film Tandem Solar Cells: Final Technical Report, 6 November 2003 - 5 January 2007  

DOE Green Energy (OSTI)

The objective of this research program was to develop approaches for a transparent wide-bandgap cell to be used in a thin-film tandem polycrystalline solar cell that can ultimately attain 25% efficiency. Specific goals included the research and development of Cu(InGa)(SeS)2 and Cd1-xZnxTe alloys with a bandgap from 1.5 to 1.8 eV, demonstrating the potential of a 15% cell efficiency with a transparent contact, and supporting the High Performance PV Program. This Final Report presents results that emphasize the 3rd phase of the program.

Shafarman, W.; McCandless, B.

2008-08-01T23:59:59.000Z

31

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...

32

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

33

Point defect engineered Si sub-bandgap light-emitting diode  

E-Print Network (OSTI)

Point defect engineered Si sub-bandgap light-emitting diode Jiming Bao1 , Malek Tabbal1,2 , Taegon light emission in Si and demonstrate a sub-bandgap light emitting diode based on the introduction.3670) Light-emitting diodes; (160.6000) Semiconductors; (130-0250) Optoelectronics. References and links 1. S

34

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

35

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

36

High Performance Wide Bandgap Power Electronics  

Science Conference Proceedings (OSTI)

Symposium, Advanced Materials for Power Electronics, Power Conditioning, and ... therefore, designers unknowingly navigate the design space with a lack of ...

37

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.

38

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.

39

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

40

Bilayer Graphene Gets a Bandgap  

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

mobility and other unique features hold great promise for nanoscale electronics and photonics. But without a bandgap, graphene's promise can't be realized. As with monolayer...

Note: This page contains sample records for the topic "wide bandgap 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.


41

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

42

Bandgap Engineering | Open Energy Information  

Open Energy Info (EERE)

Engineering Engineering Jump to: navigation, search Name Bandgap Engineering Place Woburn, Massachusetts Zip 1801 Sector Efficiency Product US-based company developing highly tunable and inexpensive methods for nano-structuring silicon and is applying these technologies to high efficiency photovoltaic systems and high capacity Li-ion batteries. References Bandgap Engineering[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Bandgap Engineering is a company located in Woburn, Massachusetts . References ↑ "Bandgap Engineering" Retrieved from "http://en.openei.org/w/index.php?title=Bandgap_Engineering&oldid=342515" Categories: Clean Energy Organizations

43

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

44

A low-noise bandgap voltage reference employing dynamic element matching  

E-Print Network (OSTI)

Bandgap voltages references are widely used in IC design, but are sensitive to low-frequency noise and component mismatch. This thesis describes the design and testing of a new IC voltage reference that targets these issues ...

Herbst, Steven (Steven G.)

2011-01-01T23:59:59.000Z

45

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

46

Session X: Narrow Bandgap Semiconductors: Infared Detectors and ...  

Science Conference Proceedings (OSTI)

Jun 24, 2010 ... Quinternary materials, although complex, offer a higher degree of .... Albuquerque, NM 87106; 2College of Optical Sciences, University of ...

47

Electronic structure characterization and bandgap engineeringofsolar hydrogen materials  

DOE Green Energy (OSTI)

Bandgap, band edge positions as well as the overall band structure of semiconductors are of crucial importance in photoelectrochemical and photocatalytic applications. The energy position of the band edge level can be controlled by the electronegativity of the dopants, the pH of the solution (flatband potential variation of 60 mV per pH unit), as well as by quantum confinement effects. Accordingly, band edges and bandgap can be tailored to achieve specific electronic, optical or photocatalytic properties. Synchrotron radiation with photon energy at or below 1 keV is giving new insight into such areas as condensed matter physics and extreme ultraviolet optics technology. In the soft x-ray region, the question tends to be, what are the electrons doing as they migrated between the atoms. In this paper, I will present a number of soft x-ray spectroscopic study of nanostructured 3d metal compounds Fe{sub 2}O{sub 3} and ZnO.

Guo, Jinghua

2007-11-01T23:59:59.000Z

48

ESS 2012 Peer Review - Engineered Gate Oxides for Wide Bandgap...  

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

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...

49

Bandgap Engineering Inc | Open Energy Information  

Open Energy Info (EERE)

Bandgap Engineering Inc Bandgap Engineering Inc Name Bandgap Engineering Inc Address 6 Gill Street Place Woburn, Massachusetts Zip 01801 Sector Solar Product Developing high efficiency solar cells Year founded 2007 Number of employees 1-10 Phone number 781-902-0310 Website http://www.bandgap.com/ Coordinates 42.5106626°, -71.1476966° 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":42.5106626,"lon":-71.1476966,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

50

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

51

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

52

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

53

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...

54

Bandgap Engineering in High-Efficiency Multijunction Concentrator Cells  

DOE Green Energy (OSTI)

This paper discusses semiconductor device research paths under investigation with the aim of reaching the milestone efficiency of 40%. A cost analysis shows that achieving very high cell efficiencies is crucial for the realization of cost-effective photovoltaics, because of the strongly leveraging effect of efficiency on module packaging and balance-of systems costs. Lattice-matched (LM) GaInP/ GaInAs/ Ge 3-junction cells have achieved the highest independently confirmed efficiency at 175 suns, 25?C, of 37.3% under the standard AM1.5D, low-AOD terrestrial spectrum. Lattice-mismatched, or metamorphic (MM), materials offer still higher potential efficiencies, if the crystal quality can be maintained. Theoretical efficiencies well over 50% are possible for a MM GaInP/ 1.17-eV GaInAs/ Ge 3-junction cell limited by radiative recombination at 500 suns. The bandgap - open circuit voltage offset, (Eg/q) - Voc, is used as a valuable theoretical and experimental tool to characterize multijunction cells with subcell bandgaps ranging from 0.7 to 2.1 eV. Experimental results are presented for prototype 6-junction cells employing an active {approx}1.1-eV dilute nitride GaInNAs subcell, with active-area efficiency greater than 23% and over 5.3 V open-circuit voltage under the 1-sun AM0 space spectrum. Such cell designs have theoretical efficiencies under the terrestrial spectrum at 500 suns concentration exceeding 55% efficiency, even for lattice-matched designs.

King, R. R.; Sherif, R. A.; Kinsey, G. S.; Kurtz, S.; Fetzer, C. M.; Edmondson, K. M.; Law, D. C.; Cotal, H. L.; Krut, D. D.; Ermer, J. H.; Karam, N. H.

2005-08-01T23:59:59.000Z

55

Monolithic, multi-bandgap, tandem, ultra-thin, strain-counterbalanced, photovoltaic energy converters with optimal subcell bandgaps  

SciTech Connect

Modeling a monolithic, multi-bandgap, tandem, solar photovoltaic converter or thermophotovoltaic converter by constraining the bandgap value for the bottom subcell to no less than a particular value produces an optimum combination of subcell bandgaps that provide theoretical energy conversion efficiencies nearly as good as unconstrained maximum theoretical conversion efficiency models, but which are more conducive to actual fabrication to achieve such conversion efficiencies than unconstrained model optimum bandgap combinations. Achieving such constrained or unconstrained optimum bandgap combinations includes growth of a graded layer transition from larger lattice constant on the parent substrate to a smaller lattice constant to accommodate higher bandgap upper subcells and at least one graded layer that transitions back to a larger lattice constant to accommodate lower bandgap lower subcells and to counter-strain the epistructure to mitigate epistructure bowing.

Wanlass, Mark W. (Golden, CO); Mascarenhas, Angelo (Lakewood, CO)

2012-05-08T23:59:59.000Z

56

ICSCRM 2005  

Science Conference Proceedings (OSTI)

Wide bandgap semiconductors, typically defined as materials exhibiting an electronic bandgap greater than 2.9 eV, are emerging as materials capable of driving ...

57

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

58

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

59

Changes related to "Bandgap Engineering" | Open Energy Information  

Open Energy Info (EERE)

period. Retrieved from "http:en.openei.orgwikiSpecial:RecentChangesLinkedBandgapEngineering" Atom Special pages About us Disclaimers Energy blogs Developer services...

60

Pages that link to "Bandgap Engineering" | Open Energy Information  

Open Energy Info (EERE)

100 | 250 | 500) Retrieved from "http:en.openei.orgwikiSpecial:WhatLinksHereBandgapEngineering" Special pages About us Disclaimers Energy blogs Developer services OpenEI...

Note: This page contains sample records for the topic "wide bandgap 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

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

62

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

63

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

64

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

65

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

66

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

67

Pages that link to "Bandgap Engineering Inc" | Open Energy Information  

Open Energy Info (EERE)

100 | 250 | 500) Retrieved from "http:en.openei.orgwikiSpecial:WhatLinksHereBandgapEngineeringInc" Special pages About us Disclaimers Energy blogs Developer services OpenEI...

68

Photoelectrochemistry, Electronic Structure, and Bandgap Sizes of Semiconducting Cu(I)-Niobates and Cu(I)-Tantalates  

DOE Green Energy (OSTI)

Semiconducting metal-oxides have remained of intense research interest owing to their potential for achieving efficient solar-driven photocatalytic reactions in aqueous solutions that occur as a result of their bandgap excitation. The photocatalytic reduction of water or carbon dioxide to generate hydrogen or hydrocarbon fuels, respectively, can be driven on p-type (photocathodic) electrodes with suitable band energies. However, metal-oxide semiconductors are typically difficult to dope as p-type with a high mobility of carriers. The supported research led to the discovery of new p-type Cu(I)-niobate and Cu(I)-tantalate film electrodes that can be prepared on FTO glass. New high-purity flux syntheses and the full structural determination of several Cu(I)-containing niobates and tantalates have been completed, as well as new investigations of their optical and photoelectrochemical properties and electronic structures via density-functional theory calculations. For example, CuNbO3, Cu5Ta11O30 and CuNb3O8 were prepared in high purity and their structures were characterized by both single-crystal and powder X-ray diffraction techniques. These two classes of Cu(I)-containing compounds exhibit optical bandgap sizes ranging from ~1.3 eV to ~2.6 eV. Photoelectrochemical measurements of these compounds show strong photon-driven cathodic currents that confirm the p-type semiconductor behavior of CuNbO3, CuNb3O8, and Cu5Ta11O30. Incident-photon-to-current efficiencies are measured that approach greater than ~1%. Electronic-structure calculations based on density functional theory reveal the visible-light absorption stems from a nearly-direct bandgap transition involving a copper-to-niobium or tantalum (d10 to d0) charge-transfer excitations.

Maggard, Paul A.

2013-11-14T23:59:59.000Z

69

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,...

70

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

71

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

72

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

73

Thermophotovoltaic energy conversion using photonic bandgap selective emitters  

DOE Patents (OSTI)

A method for thermophotovoltaic generation of electricity comprises heating a metallic photonic crystal to provide selective emission of radiation that is matched to the peak spectral response of a photovoltaic cell that converts the radiation to electricity. The use of a refractory metal, such as tungsten, for the photonic crystal enables high temperature operation for high radiant flux and high dielectric contrast for a full 3D photonic bandgap, preferable for efficient thermophotovoltaic energy conversion.

Gee, James M. (Albuquerque, NM); Lin, Shawn-Yu (Albuquerque, NM); Fleming, James G. (Albuquerque, NM); Moreno, James B. (Albuquerque, NM)

2003-06-24T23:59:59.000Z

74

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

75

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

76

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

77

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

78

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

79

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"

80

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

Note: This page contains sample records for the topic "wide bandgap 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.


81

High-efficiency, monolithic, multi-bandgap, tandem photovoltaic energy converters  

DOE Patents (OSTI)

A monolithic, multi-bandgap, tandem solar photovoltaic converter has at least one, and preferably at least two, subcells grown lattice-matched on a substrate with a bandgap in medium to high energy portions of the solar spectrum and at least one subcell grown lattice-mismatched to the substrate with a bandgap in the low energy portion of the solar spectrum, for example, about 1 eV.

Wanlass, Mark W. (Golden, CO)

2011-11-29T23:59:59.000Z

82

Reactivation of sub-bandgap absorption in chalcogen-hyperdoped silicon  

Science Conference Proceedings (OSTI)

Silicon doped with nonequilibrium concentrations of chalcogens using a femtosecond laser exhibits near-unity absorption of sub-bandgap photons to wavelengths of at least 2500 nm. Previous studies have shown that sub-bandgap absorptance decreases with thermal annealing up to 1175 K and that the absorption deactivation correlates with chalcogen diffusivity. In this work, we show that sub-bandgap absorptance can be reactivated by annealing at temperatures between 1350 and 1550 K followed by fast cooling (>50 K/s). Our results suggest that the defects responsible for sub-bandgap absorptance are in equilibrium at high temperatures in hyperdoped Si:chalcogen systems.

Newman, Bonna K.; Buonassisi, Tonio [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Sher, Meng-Ju [Department of Physics, Harvard University, 9 Oxford Street, Cambridge, Massachusetts 02138 (United States); Mazur, Eric [Department of Physics, Harvard University, 9 Oxford Street, Cambridge, Massachusetts 02138 (United States); School of Engineering and Applied Sciences, Harvard University, 9 Oxford Street, Cambridge, Massachusetts 02138 (United States)

2011-06-20T23:59:59.000Z

83

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...

84

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

85

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

86

Effect of Sub-Bandgap Illumination on the Internal Electric Field of CdZnTe  

SciTech Connect

Post-growth manipulation of the internal electric field in CdZnTe crystals using sub-bandgap illumination is measured as a function of temperature through infrared (IR) transmission measurements. Using near sub-bandgap IR illumination, both the optical de-trapping of charge carriers and the reduction in carrier recombination increased the mobility lifetime in the crystal. The increased carrier transport is a direct result of decreased hole and electron trapping in addition to other underlying mechanisms. Concentration of the electric field near the cathode is also observed. We measured the electric field distribution with sub-bandgap illumination as a function of temperature via the Pockels effect.

Washington, A.

2011-09-16T23:59:59.000Z

87

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

88

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

89

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

90

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

91

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

92

Photonic bandgap fibers for transmitting high peak-power pulses in the near infrared  

E-Print Network (OSTI)

Hollow-core photonic bandgap fibers (PBG) offer the opportunity to suppress highly the optical absorption and nonlinearities of their constituent materials, which makes them viable candidates for transmitting high-peak ...

Ruff, Zachary

2010-01-01T23:59:59.000Z

93

Room-temperature direct bandgap electroluminesence from Ge-on-Si light-emitting diodes  

E-Print Network (OSTI)

We report what we believe to be the first demonstration of direct bandgap electroluminescence (EL) from Ge/Si heterojunction light-emitting diodes (LEDs) at room temperature. In-plane biaxial tensile strain is used to ...

Sun, Xiaochen

94

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

95

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

96

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

97

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

98

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

99

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

100

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

Note: This page contains sample records for the topic "wide bandgap 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

Optical properties of thin semiconductor device structures with reflective back-surface layers  

DOE Green Energy (OSTI)

Ultrathin semiconductor device structures incorporating reflective internal or back surface layers have been investigated recently as a means of improving photon recuperation, eliminating losses associated with free carrier absorption in conductive substrates and increasing the above bandgap optical thickness of thermophotovoltaic device structures. However, optical losses in the form of resonance absorptions in these ultrathin devices have been observed. This behavior in cells incorporating epitaxially grown FeAl layers and in devices that lack a substrate but have a back-surface reflector (BSR) at the rear of the active layers has been studied experimentally and modeled effectively. For thermophotovoltaic devices, these resonances represent a significant loss mechanism since the wavelengths at which they occur are defined by the active TPV cell thickness of {approximately} 2--5 microns and are in a spectral range of significant energy content for thermal radiators. This study demonstrates that ultrathin semiconductor structures that are clad by such highly reflective layers or by films with largely different indices of refraction display resonance absorptions that can only be overcome through the implementation of some external spectral control strategy. Effective broadband, below-bandgap spectral control using a back-surface reflector is only achievable using a large separation between the TPV active layers and the back-surface reflector.

Clevenger, M.B.; Murray, C.S. [Westinghouse Electric Co., West Mifflin, PA (United States); Ringel, S.A.; Sachs, R.N.; Qin, L. [Ohio State Univ., Columbus, OH (United States). Dept. of Electrical Engineering; Charache, G.W.; Depoy, D.M. [Lockheed Martin, Inc., Schenectady, NY (United States)

1998-11-01T23:59:59.000Z

102

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

103

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

104

Tandem Polymer Solar Cells Featuring a Spectrally Matched Low-Bandgap Polymer  

SciTech Connect

Tandem solar cells provide an effective way to harvest a broader spectrum of solar radiation by combining two or more solar cells with different absorption bands. However, for polymer solar cells, the performance of tandem devices lags behind single-layer solar cells mainly due to the lack of a suitable low-bandgap polymer. Here, we demonstrate highly efficient single and tandem polymer solar cells featuring a low-bandgap conjugated polymer (PBDTT-DPP: bandgap, {approx}1.44 eV). A single-layer device based on the polymer provides a power conversion efficiency of {approx}6%. When the polymer is applied to tandem solar cells, a power conversion efficiency of 8.62% is achieved, which is, to the best of our knowledge, the highest certified efficiency for a polymer solar cell to date.

Dou, L.; You, J.; Yang, J.; Chen, C. C.; He, Y.; Murase, S.; Moriarty, T.; Emery, K.; Li, G.; Yang, Y.

2012-03-01T23:59:59.000Z

105

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

106

Dopant type and/or concentration selective dry photochemical etching of semiconductor materials  

DOE Patents (OSTI)

A method of selectively photochemically dry etching a first semiconductor material of a given composition in the presence of a second semiconductor material which is of a composition different from said first material, said second material substantially not being etched during said method, comprises subjecting both materials to the same photon flux of an energy greater than their respective direct bandgaps and to the same gaseous chemical etchant under conditions where said etchant would be ineffective for chemical etching of either material were the photons not present, said conditions also being such that the resultant electronic structure of the first semiconductor material under said photon flux is sufficient for the first material to undergo substantial photochemical etching under said conditions and being such that the resultant electronic structure of the second semiconductor material under said photon flux is not sufficient for the second material to undergo substantial photochemical etching under said conditions. In a preferred mode, the materials are subjected to a bias voltage which suppresses etching in n- or p- type material but not in p- or n-type material, respectively; or suppresses etching in the more heavily doped of two n-type or two p-type materials.

Ashby, Carol I. H. (Edgewood, NM); Dishman, James L. (Albuquerque, NM)

1987-01-01T23:59:59.000Z

107

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

108

Controlling terahertz waves with meta-materials and photonic bandgap structures  

SciTech Connect

We will describe research conducted at Los Alamos National Laboratory towards developing components for controlling terahertz waves. We employ meta-materials and, particularly, meta-films, as very compact absorbers for controlling quasioptical beams. We believe that dielectric photonic bandgap structures could replace ordinary metal waveguide devices at THz, since metal structures become extremely lossy in this frequency range.

Shchegolkov, Dmitry [Los Alamos National Laboratory; Azad, Abul [Los Alamos National Laboratory; O' Hara, John F [Los Alamos National Laboratory; Moody, Nathan A [Los Alamos National Laboratory; Simakov, Evgenya I [Los Alamos National Laboratory

2010-12-07T23:59:59.000Z

109

Analysis and design of terahertz microstrip antenna on photonic bandgap material  

Science Conference Proceedings (OSTI)

In this paper, a dielectric slab with periodic implantation of the air gaps has been analyzed. An effective dielectric permittivity of the 1-D photonic bandgap substrate material (PBG material) with host material as Polytetrafluoroethylene (PTFE) has ... Keywords: Directivity, Electromagnetic band gap, Metamaterial, Microstrip patch antenna, Radiation efficiency, Terahertz spectrum

Kumud Ranjan Jha; G. Singh

2012-12-01T23:59:59.000Z

110

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

111

On the Importance of Bandgap Formation in Graphene for Analog Device Applications  

Science Conference Proceedings (OSTI)

We present a study that identifies the ideal bandgap value in graphene devices, e.g., through size quantization in graphene nanoribbons (GNRs), to enable graphene-based high-performance RF applications. When considering a ballistic graphene GNR-LNA, ...

Saptarshi Das; Joerg Appenzeller

2011-09-01T23:59:59.000Z

112

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

113

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

114

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

115

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

116

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

117

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...

118

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

119

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...

120

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

Note: This page contains sample records for the topic "wide bandgap 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

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

122

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

123

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

124

Enhanced chemiluminescent detection scheme for trace vapor sensing in pneumatically-tuned hollow core photonic bandgap fibers  

E-Print Network (OSTI)

We demonstrate an in-fiber gas phase chemical detection architecture in which a chemiluminescent (CL) reaction is spatially and spectrally matched to the core modes of hollow photonic bandgap (PBG) fibers in order to enhance ...

Stolyarov, Alexander Mark

125

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

126

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

127

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

128

Final Report: Bandgap-Engineered Thermophotovoltaic Devices for Hi Efficiency Radioisotope Power, July 9, 1996 - July 8, 1999  

DOE Green Energy (OSTI)

During Phase I the feasibility of fabricating high-performance, low bandgap (0.58ev)PV cells by thermally diffusing p-n junctions in GaSb based quaternary materials was established. During phase II, bandgap engineered thermophotovoltaic (TPV) cells were optimized, development of a low-cost build source material for quaternary devices was investigated, and a diesel-fueled, TPV test-bed was built and tested allowing its performance to be characterized.

Sundaram, V; Morgan, M.D.; Horne, W.E.

2000-03-15T23:59:59.000Z

129

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

130

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

131

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

132

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

133

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

134

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

135

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...

136

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

137

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

138

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

139

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

140

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

Note: This page contains sample records for the topic "wide bandgap 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.


141

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.

142

Solar Superabsorption of Semiconductor Materials  

E-Print Network (OSTI)

We theoretically demonstrate the fundamental limit in volume for given materials (e.g. Si, a-Si, CdTe) to fully absorb the solar radiation above bandgap, which we refer as solar superabsorption limit. We also point out the general principles for experimentally designing light trapping structures to approach the superabsorption. This study builds upon an intuitive model, coupled leaky mode theory (CLMT), for the analysis of light absorption in nanostructures. The CLMT provides a useful variable transformation. Unlike the existing methods that rely on information of physical features (e.g. morphology, dimensionality) to analyze light absorption, the CLMT can evaluate light absorption in given materials with only two variables, the radiative loss and the resonant wavelength, of leaky modes, regardless the physical features of the materials. This transformation allows for surveying the entire variable space to find out the solar superabsorption and provides physical insights to guide the design of solar superabso...

Yu, Yiling; Cao, Linyou

2013-01-01T23:59:59.000Z

143

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

144

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

145

Thin Films - Preparation and Properties IV - Programmaster.org  

Science Conference Proceedings (OSTI)

Aug 5, 2010 ... In order to improve the performance of wide bandgap semiconductor such as TiO 2 or ZnO, a variety of micro-grids were deposited on the ...

146

Employment of PS Template in the Surface Modification  

Science Conference Proceedings (OSTI)

Abstract Scope, In order to improve the performance of wide bandgap semiconductor such as TiO2 or ZnO, a variety of micro-grids were deposited ...

147

TMS2014 Session List  

Science Conference Proceedings (OSTI)

Feb 17, 2014 ... Advanced Materials for Power Electronics, Power Conversion, and Power Conditioning. Mon 02/17/ ... Wide Bandgap Semiconductors Materials Growth and Characterization. Tue 02/18/ ..... Paste Plant Operations. Tue 02/18/ ...

148

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...

149

Morphological Characterization of a LowBandgap Crystalline Polymer:PCBM Bulk Heterojunction Solar Cells  

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

2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim Full paper 1 wileyonlinelibrary.com Adv. Energy Mater. 2011, XX, 1-9 www.MaterialsViews.com www.advenergymat.de 1. Introduction Bulk heterojunction (BHJ) organic photovoltaic (OPV) sys- tems have attracted increasing interest due to their low-cost and potential for highly scalable solution processing. How- ever, achieving efficiencies in excess of 10% is an important milestone in making OPV devices viable economically. While there have been advances in the synthesis of novel low bandgap polymers and block copolymers with tailored morphologies, translating these advances to large scale production mandates understanding the morphology of the active layer developed during processing, the relationship of the

150

Low-bandgap double-heterostructure InAsP/GaInAs photovoltaic converters  

DOE Patents (OSTI)

A low-bandgap, double-heterostructure PV device is provided, including in optical alignment a first InP.sub.1-y As.sub.y n-layer formed with an n-type dopant, an Ga.sub.x In.sub.1-x As absorber layer, the absorber layer having an n-region formed with an n-type dopant and an p-region formed with a p-type dopant to form a single pn-junction, and a second InP.sub.1-y As.sub.y p-layer formed with a p-type dopant, wherein the first and second layers are used for passivation and minority carrier confinement of the absorber layers.

Wanlass, Mark W. (Golden, CO)

2001-01-01T23:59:59.000Z

151

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

152

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

153

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

154

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 ...

155

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...

156

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...

157

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...

158

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...

159

Thermally Driven Crossover from Indirect toward Direct Bandgap in 2D Semiconductors: MoSe2 versus MoS2  

E-Print Network (OSTI)

transition may occur from the adsorbed hydroxyl radi- cals (MOx[·OH]) to the lattice of the metal oxide anode, forming the higher oxide MOx+1, and the oxygen forms oxidizing organic substance to different products [21,23]. Since MOx[·OH] favors electrochemical combustion while MOx+1 favors electrochemical conversion [23

Wu, Junqiao

160

ZnMgO by APCVD Enabling High-Performance Mid-bandgap CIGS on Polyimide Modules: October 2009--October 2010  

DOE Green Energy (OSTI)

This Pre-Incubator project was designed to increase the 'real world' CIGS based photovoltaic module performance and decrease the Levelized Cost of Energy (LCOE) of systems utilizing those modules compared to our traditional CIGS based photovoltaic modules. This was enabled by a) increasing the CIGS bandgap and b) developing better matched device finishing layers to the mid-bandgap CIGS based photovoltaics; including window and buffer layers (and eventually the TCO). Incremental progress in the novel device performance was demonstrated throughout the program, and ultimately achieved performance results that exceeded the milestones ahead of schedule. Metal-oxide buffer layer devices with mid-bandgap CIGS alloys on polyimide substrates were produced with efficiencies of over 12%. Corresponding mid-bandgap devices with CdS buffers produced over 13% efficient devices. Furthermore, no obvious degradation in the device performance has been observed to date, after proper storage ambient of the different types of unencapsulated devices were identified.

Woods, L.

2011-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "wide bandgap 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
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161

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...

162

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

163

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

164

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

165

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

166

Bandgap Engineering of InP QDs Through Shell Thickness and Composition  

SciTech Connect

Fields as diverse as biological imaging and telecommunications utilize the unique photophysical and electronic properties of nanocrystal quantum dots (NQDs). The development of new NQD compositions promises material properties optimized for specific applications, while addressing material toxicity. Indium phosphide (InP) offers a 'green' alternative to the traditional cadmium-based NQDs, but suffers from extreme susceptibility to oxidation. Coating InP cores with more stable shell materials significantly improves nanocrystal resistance to oxidation and photostability. We have investigated several new InP-based core-shell compositions, correlating our results with theoretical predictions of their optical and electronic properties. Specifically, we can tailor the InP core-shell QDs to a type-I, quasi-type-II, or type-II bandgap structure with emission wavelengths ranging from 500-1300 nm depending on the shell material used (ZnS, ZnSe, CdS, or CdSe) and the thickness of the shell. Single molecule microscopy assessments of photobleaching and blinking are used to correlate NQD properties with shell thickness.

Dennis, Allison M. [Los Alamos National Laboratory; Mangum, Benjamin D. [Los Alamos National Laboratory; Piryatinski, Andrei [Los Alamos National Laboratory; Park, Young-Shin [Los Alamos National Laboratory; Htoon, Han [Los Alamos National Laboratory; Hollingsworth, Jennifer A. [Los Alamos National Laboratory

2012-06-21T23:59:59.000Z

167

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.

168

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

169

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

170

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

171

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

172

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

173

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

174

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

175

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

176

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

177

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

178

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

179

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

180

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

Note: This page contains sample records for the topic "wide bandgap 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

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

182

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":""}]}

183

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":""}]}

184

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

185

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

186

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

187

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

188

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

189

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

190

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

191

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

192

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

193

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

194

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...

195

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

196

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

197

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

198

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

199

In-line Mach-Zehnder interferometer composed of microtaper and long-period grating in all-solid photonic bandgap fiber  

Science Conference Proceedings (OSTI)

We report a compact in-line Mach-Zehnder interferometer combining a microtaper with a long-period grating (LPG) in a section of all-solid photonic bandgap fiber. Theoretical and experimental investigations reveal that the interferometer works from the interference between the fundamental core mode and the LP{sub 01} cladding supermodes. The mechanism underlying the mode coupling caused by the microtaper can be attributed to a bandgap-shifting as the fiber diameter is abruptly scaled down. In addition, the interferometer designed to strengthen the coupling ratio of the long-period grating has a promising practical application in the simultaneous measurement of curvature and temperature.

Wu Zhifang [Key Laboratory of Optical Information and Technology, Ministry of Education and Institute of Modern Optics, Nankai University, Tianjin 300071 (China); OPTIMUS, School of Electrical and Electronics Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 637553 (Singapore); Liu Yange; Wang Zhi; Han Tingting; Li Shuo [Key Laboratory of Optical Information and Technology, Ministry of Education and Institute of Modern Optics, Nankai University, Tianjin 300071 (China); Jiang Meng; Ping Shum, Perry [OPTIMUS, School of Electrical and Electronics Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 637553 (Singapore); CINTRA CNRS/NTU/THALES, UMI 3288, Research Techno Plaza, 50 Nanyang Drive, Border X Block, Level 6, Singapore 637553 (Singapore); Quyen Dinh, Xuan [CINTRA CNRS/NTU/THALES, UMI 3288, Research Techno Plaza, 50 Nanyang Drive, Border X Block, Level 6, Singapore 637553 (Singapore); Thales Solutions Asia Pte Ltd, R and T Department, 28 Changi North Rise, Singapore 498755 (Singapore)

2012-10-01T23:59:59.000Z

200

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":""}]}

Note: This page contains sample records for the topic "wide bandgap 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.


201

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

202

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

203

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"

204

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

205

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

206

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...

207

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...

208

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

209

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

210

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 ...

211

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

212

Visible light surface emitting semiconductor laser  

DOE Patents (OSTI)

A vertical-cavity surface-emitting laser is disclosed comprising a laser cavity sandwiched between two distributed Bragg reflectors. The laser cavity comprises a pair of spacer layers surrounding one or more active, optically emitting quantum-well layers having a bandgap in the visible which serve as the active optically emitting material of the device. The thickness of the laser cavity is m .lambda./2n.sub.eff where m is an integer, .lambda. is the free-space wavelength of the laser radiation and n.sub.eff is the effective index of refraction of the cavity. Electrical pumping of the laser is achieved by heavily doping the bottom mirror and substrate to one conductivity-type and heavily doping regions of the upper mirror with the opposite conductivity type to form a diode structure and applying a suitable voltage to the diode structure. Specific embodiments of the invention for generating red, green, and blue radiation are described.

Olbright, Gregory R. (Boulder, CO); Jewell, Jack L. (Bridgewater, NJ)

1993-01-01T23:59:59.000Z

213

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

214

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

215

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

216

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

217

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

218

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

219

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.

220

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.

Note: This page contains sample records for the topic "wide bandgap 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

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.

222

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.

223

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.

224

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.

225

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.

226

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

227

Microwave-Assisted Synthesis of II-VI Semiconductor Micro- and Nanoparticles towards Sensor Applications  

E-Print Network (OSTI)

Engineering particles at the nanoscale demands a high degree of control over process parameters during synthesis. For nanocrystal synthesis, solution-based techniques typically include application of external convective heat. This process often leads to slow heating and allows decomposition of reagents or products over time. Microwave-assisted heating provides faster, localized heating at the molecular level with near instantaneous control over reaction parameters. In this work, microwave-assisted heating has been applied for the synthesis of II-VI semiconductor nanocrystals namely, ZnO nanopods and CdX (X = Se, Te) quantum dots (QDs). Based on factors such as size, surface functionality and charge, optical properties of such nanomaterials can be tuned for application as sensors. ZnO is a direct bandgap semiconductor (3.37 eV) with a large exciton binding energy (60 meV) leading to photoluminescence (PL) at room temperature. A microwave-assisted hydrothermal approach allows the use of sub-5 nm ZnO zero-dimensional nanoparticles as seeds for generation of multi-legged quasi one-dimensional nanopods via heterogeneous nucleation. ZnO nanopods, having individual leg diameters of 13-15 nm and growing along the [0001] direction, can be synthesized in as little as 20 minutes. ZnO nanopods exhibit a broad defect-related PL spanning the visible range with a peak at ~615 nm. Optical sensing based on changes in intensity of the defect PL in response to external environment (e.g., humidity) is demonstrated in this work. Microwave-assisted synthesis was also used for organometallic synthesis of CdX(ZnS) (X = Se, Te) core(shell) QDs. Optical emission of these QDs can be altered ased on their size and can be tailored to specific wavelengths. Further, QDs were incorporated in Enhanced Green-Fluorescent Protein – Ultrabithorax (EGFP-Ubx) fusion protein for the generation of macroscale composite protein fibers via hierarchal self-assembly. Variations in EGFP- Ubx·QD composite fiber surface morphology and internal QD distribution were studied with respect to (i) time of QD addition (i.e., pre or post protein self-assembly) and (ii) QD surface charge — negatively charged QDs with dihydrolipoic acid functionalization and positively charged QDs with polyethyleneimine coating. Elucidating design motifs and understanding factors that impact the protein-nanoparticle interaction enables manipulation of the structure and mechanical properties of composite materials.

Majithia, Ravish

2013-05-01T23:59:59.000Z

228

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

229

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":""}]}

230

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

231

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

232

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

233

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

234

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

235

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

236

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)

237

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

238

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

239

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

240

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

Note: This page contains sample records for the topic "wide bandgap 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

A study of potential high band-gap photovoltaic materials for a two step photon intermediate technique in fission energy conversion. Final report  

DOE Green Energy (OSTI)

This report describes progress made to develop a high bandgap photovoltaic materials for direct conversion to electricity of excimer radiation produced by fission energy pumped laser. This report summarizes the major achievements in sections. The first section covers n-type diamond. The second section covers forced diffusion. The third section covers radiation effects. The fourth section covers progress in Schottky barrier and heterojunction photovoltaic cells. The fifth section covers cell and reactor development.

Prelas, M.A.

1996-01-24T23:59:59.000Z

242

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

243

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

244

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 ...

245

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...

246

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 ...

247

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

248

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...

249

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

250

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

251

Tuning the electronic coupling in a low-bandgap donor-acceptor copolymer via the placement of side-chains  

SciTech Connect

We present a spectroscopic and theoretical investigation of the effect of the presence and position of hexyl side-chains in the novel low-bandgap alternating donor-acceptor copolymer poly[bis-N,N-(4-octylphenyl)-bis-N,N-phenyl-1, 4-phenylenediamine-alt-5,5'-4',7',-di-2-thienyl-2',1',3'-benzothiadiazole] (T8TBT). We use electronic absorption and Raman spectroscopic measurements supported by calculations of chain conformation, electronic transitions, and Raman modes. Using these tools, we find that sterically demanding side-chain configurations induce twisting in the electronic acceptor unit and reduce the electronic interaction with the donor. This leads to a blue-shifted and weakened (partial) charge-transfer absorption band together with a higher photoluminescence efficiency. On the other hand, sterically relaxed side-chain configurations promote coupling between donor and acceptor units and exhibit enhanced absorption at the expense of luminescence efficiency. The possibility of tuning the donor-acceptor character of conjugated polymers by varying the placement of side-chains has very important ramifications for light emitting diode, Laser, display, and photovoltaic device optimization.

Oberhumer, Philipp M.; Huang, Ya-Shih; Massip, Sylvain; Albert-Seifried, Sebastian; Greenham, Neil C.; Hodgkiss, Justin M.; Friend, Richard H. [Cavendish Laboratory, J J Thomson Avenue, Cambridge CB3 0HE (United Kingdom); James, David T.; Kim, Ji-Seon [Blackett Laboratory, Imperial College, London SW7 2AZ (United Kingdom); Tu Guoli; Huck, Wilhelm T. S. [Melville Laboratory for Polymer Synthesis, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW (United Kingdom); Beljonne, David; Cornil, Jerome [Laboratory for Chemistry of Novel Materials, University of Mons, Place du Parc, 20, 7000 Mons (Belgium)

2011-03-21T23:59:59.000Z

252

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

253

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

254

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

255

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

256

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

257

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

258

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

259

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

260

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

Note: This page contains sample records for the topic "wide bandgap 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

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

262

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

263

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

264

Engineered substrates for coplanar integration of lattice-mismatched semiconductors with silicon  

E-Print Network (OSTI)

As we approach the end of traditional CMOS scaling, further improvements in integrated circuit performance and functionality will become limited by the inherently low carrier mobility and indirect bandgap of silicon. These ...

Pitera, Arthur Joseph, 1975-

2005-01-01T23:59:59.000Z

265

Self-assembled Semiconductor 0D, 1D and 2D Quantum Structures ...  

Science Conference Proceedings (OSTI)

In the present work, we present how bandgap modulation can be achieved by the introduction of self-assembled 0D, 1D and 2D quantum structures, quantum ...

266

Monolithic heteroepitaxial integration of III-V semiconductor lasers on Si substrates  

E-Print Network (OSTI)

Monolithic optoelectronic integration on silicon-based integrated circuits has to date been limited to date by the large material differences between silicon (Si) and the direct-bandgap GaAs compounds from which optoelectronic ...

Groenert, Michael

2002-01-01T23:59:59.000Z

267

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.

268

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.

269

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

270

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

271

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

272

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

273

InGaAsN Solar Cells with 1.0eV Bandgap, Lattice Matched to GaAs  

DOE Green Energy (OSTI)

The design, growth by metal-organic chemical vapor deposition, and processing of an In{sub 0.07}Ga{sub 0.93}As{sub 0.98}N{sub 0.02} solar Al, with 1.0 ev bandgap, lattice matched to GaAs is described. The hole diffusion length in annealed, n-type InGaAsN is 0.6-0.8 pm, and solar cell internal quantum efficiencies > 70% arc obwined. Optical studies indicate that defects or impurities, from InGAsN doping and nitrogen incorporation, limit solar cell performance.

Allerman, A.A.; Banas, J.J.; Gee, J.M.; Hammons, B.E.; Jones, E.D.; Kurtz, S.R.

1998-11-24T23:59:59.000Z

274

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

275

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

276

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

277

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

278

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

279

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

280

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

Note: This page contains sample records for the topic "wide bandgap 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

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

282

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":""}]}

283

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":""}]}

284

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

285

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

286

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

287

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...

288

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

289

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 ...

290

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

291

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

292

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

293

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

294

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

295

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

296

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

297

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

298

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

299

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

300

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

Note: This page contains sample records for the topic "wide bandgap 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

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

302

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

303

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

304

RUBY NANDINI GHOSH Research Associate Professor  

E-Print Network (OSTI)

University 1996 to 2004 "Wide bandgap semiconductor devices" Catalytic gate silicon carbide devices have been & Engineering Physics (1991) Thesis: "Spin Dependent Transport in a Silicon Two-Dimensional Electron Gas degradation in performance. "Fiber optic oxygen sensing" Developed a reflection mode fiber probe operating

Ghosh, Ruby N.

305

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

306

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

307

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

308

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 ...

309

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

310

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...

311

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...

312

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

313

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

314

RAMAN AND IR STUDY OF NARROW BANDGAP A-SIGE AND C-SIGE FILMS DEPOSITED USING DIFFERENT HYDROGEN DILUTION  

E-Print Network (OSTI)

chemical vapor deposition (PECVD) with a fixed germane to disilane ratio of 0.72 and a wide range], cathode deposition [2], and using disilane- germane mixture without H dilution [3] in PECVD process. A gas mixture of disilane, germane and hydrogen was used with a fixed germane to disilane ratio of 0

Deng, Xunming

315

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

316

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

317

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

318

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

319

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

320

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

Note: This page contains sample records for the topic "wide bandgap 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

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

322

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

323

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

324

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...

325

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...

326

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

327

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":""}]}

328

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

329

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

330

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

331

[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

332

(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

333

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

334

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

335

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

336

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

337

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

338

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

339

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

340

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

Note: This page contains sample records for the topic "wide bandgap 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

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

342

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

343

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

344

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

345

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

346

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

347

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

348

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

349

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

350

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

351

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

352

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

353

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

354

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

355

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

356

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

357

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.

358

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.

359

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.

360

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

Note: This page contains sample records for the topic "wide bandgap 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

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

362

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

363

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

364

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

365

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

366

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

367

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

368

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

369

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

370

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

371

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

372

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

373

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

374

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

375

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

376

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

377

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...

378

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...

379

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...

380

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

Note: This page contains sample records for the topic "wide bandgap 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

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

382

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.

383

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

384

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

385

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

386

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

387

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

388

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

389

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

390

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

391

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

392

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

393

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

394

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

395

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

396

Energy Basics: Photovoltaic Cell Materials  

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

one crystal to another. Bandgap The bandgap of a semiconductor material is the minimum energy needed to move an electron from its bound state within an atom to a free state. This...

397

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.

398

Bilayer Graphene Gets a Bandgap  

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

2009 00:00 Graphene is the two-dimensional crystalline form of carbon whose extraordinary electron mobility and other unique features hold great promise for nanoscale electronics...

399

Blog Feed: Vehicles | Department of Energy  

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

Blog Feed: Vehicles Blog Feed: Vehicles Blog Feed: Vehicles RSS January 16, 2014 Live Discussion on Energy 101: Fuel Cells Watch our Google+ Hangout on Energy 101: Fuel Cells to learn everything you need to know about fuel cells. January 15, 2014 Wide Bandgap Semiconductors: Essential to Our Technology Future Learn how wide bandgap semiconductor-based power electronics could impact clean energy technology and our daily lives. January 6, 2014 The Clean Energy Economy in Three Charts Over the last five years, American inventors and investors have made significant progress in developing and deploying key clean energy technologies -- supported by Energy Department policies. January 3, 2014 Our Best Energy Videos of 2013 Check out our best videos from 2013 -- from Secretary Moniz's first day on

400

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

Note: This page contains sample records for the topic "wide bandgap 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

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

402

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

403

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

404

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

405

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

406

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

407

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

408

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

409

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

410

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

411

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

412

Dye-sensitized solar cells  

DOE Patents (OSTI)

A low-cost dye-sensitized Schottky barrier solar cell is comprised of a substrate of semiconductor with an ohmic contact on one face, a sensitizing dye adsorbed onto the opposite face of the semiconductor, a transparent thin-film layer of a reducing agent over the dye, and a thin-film layer of metal over the reducing agent. The ohmic contact and metal layer constitute electrodes for connection to an external circuit and one or the other or both are made transparent to permit light to penetrate to the dye and be absorbed therein for generating electric current. The semiconductor material chosen to be the substrate is one having a wide bandgap and which therefore is transparent; the dye selected is one having a ground state within the bandgap of the semiconductor to generate carriers in the semiconductor, and a first excited state above the conduction band edge of the semiconductor to readily conduct electrons from the dye to the semiconductor; the reducing agent selected is one having a ground state above the ground state of the sensitizer to provide a plentiful source of electrons to the dye during current generation and thereby enhance the generation; and the metal for the thin-film layer of metal is selected to have a Fermi level in the vicinity of or above the ground state of the reducing agent to thereby amply supply electrons to the reducing agent. 3 figs.

Skotheim, T.A.

1980-03-04T23:59:59.000Z

413

Dye-sensitized Schottky barrier solar cells  

DOE Patents (OSTI)

A low-cost dye-sensitized Schottky barrier solar cell comprised of a substrate of semiconductor with an ohmic contact on one face, a sensitizing dye adsorbed onto the opposite face of the semiconductor, a transparent thin-film layer of a reducing agent over the dye, and a thin-film layer of metal over the reducing agent. The ohmic contact and metal layer constitute electrodes for connection to an external circuit and one or the other or both are made transparent to permit light to penetrate to the dye and be absorbed therein for generating electric current. The semiconductor material chosen to be the substrate is one having a wide bandgap and which therefore is transparent; the dye selected is one having a ground state within the bandgap of the semiconductor to generate carriers in the semiconductor, and a first excited state above the conduction band edge of the semiconductor to readily conduct electrons from the dye to the semiconductor; the reducing agent selected is one having a ground state above the ground state of the sensitizer to provide a plentiful source of electrons to the dye during current generation and thereby enhance the generation; and the metal for the thin-film layer of metal is selected to have a Fermi level in the vicinity of or above the ground state of the reducing agent to thereby amply supply electrons to the reducing agent.

Skotheim, Terje A. (Berkeley, CA)

1978-01-01T23:59:59.000Z

414

Dye-sensitized solar cells  

DOE Patents (OSTI)

A low-cost dye-sensitized Schottky barrier solar cell comprised of a substrate of semiconductor with an ohmic contact on one face, a sensitizing dye adsorbed onto the opposite face of the semiconductor, a transparent thin-film layer of a reducing agent over the dye, and a thin-film layer of metal over the reducing agent. The ohmic contact and metal layer constitute electrodes for connection to an external circuit and one or the other or both are made transparent to permit light to penetrate to the dye and be absorbed therein for generating electric current. The semiconductor material chosen to be the substrate is one having a wide bandgap and which therefore is transparent; the dye selected is one having a ground state within the bandgap of the semiconductor to generate carriers in the semiconductor, and a first excited state above the conduction band edge of the semiconductor to readily conduct electrons from the dye to the semiconductor; the reducing agent selected is one having a ground state above the ground state of the sensitizer to provide a plentiful source of electrons to the dye during current generation and thereby enhance the generation; and the metal for the thin-film layer of metal is selected to have a Fermi level in the vicinity of or above the ground state of the reducing agent to thereby amply supply electrons to the reducing agent.

Skotheim, Terje A. (Berkeley, CA)

1980-01-01T23:59:59.000Z

415

Small Business Innovation Research Program Topics - October 28, 2013.  

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

TECHNOLOGY TRANSFER OPPORTUNITIES ............................... ERROR! BOOKMARK NOT DEFINED. TECHNOLOGY TRANSFER OPPORTUNITIES ............................... ERROR! BOOKMARK NOT DEFINED. FAST-TRACK (COMBINED PHASE I AND PHASE II) .................... ERROR! BOOKMARK NOT DEFINED. PROGRAM AREA OVERVIEW: OFFICE OF ENERGY EFFICIENCY AND RENEWABLE ENERGY ....... 7 1. ADVANCED MANUFACTURING ........................................................................................................................... 7 a. Manufacturing Improvements of Aluminum Nitride (AlN) for Wide Bandgap Semiconductor Power Devices ................................................................................................................................................................... 7 b. Rapid Heat Treatment of Metals........................................................................................................................... 8

416

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

417

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...

418

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

419

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

420

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

Note: This page contains sample records for the topic "wide bandgap 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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421

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

422

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

423

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

424

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

425

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

426

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

427

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

428

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

429

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

430

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.

431

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

432

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

433

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

434

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

435

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

436

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

437

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

438

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

439

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

440

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

Note: This page contains sample records for the topic "wide bandgap 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

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

442

X-ray and photoelectron spectroscopy of the structure, reactivity, and electronic structure of semiconductor nanocrystals  

E-Print Network (OSTI)

Figure 2-5 FESEM of 60Å CdSe nanocrystals on hexanedithiol/properties of semiconductor (CdSe, InAs) nanocrystals andCdSe)..

Hamad, Kimberly S.

2000-01-01T23:59:59.000Z

443

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

444

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

445

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

446

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

447

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

448

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

449

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.

450

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

451

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

452

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

453

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

454

From semiconductor-semiconductor transition (42 K) to the highest- Tc organic superconductor,. kappa. -(ET) sub 2 Cu(N(CN) sub 2 )Cl ( Tc = 12. 5 K)  

Science Conference Proceedings (OSTI)

The discovery of an organic superconductor with the highest transition temperature (125 K) recorded following the suppression of a semiconductor-semiconductor transition (42 K) is reported. The reported compound is a kappa-phase superconductor, kappa-(ET){sub 2}Cu(N(CN){sub 2})Cl, which is isostructural with the recently prepared ambient-pressure superconductor kappa-(ET){sub 2}Cu(N(CN){sub 2})Br with a transition temperature of 11.5 K that has been previously reported. Band electronic structural calculations show the newly discovered compound to be a two-dimensional metal. 15 refs., 2 figs.

Williams, J.M.; Kini, A.M.; Wang, H.H.; Carlson, K.D.; Geiser, U.; Montgomery, L.K.; Pyrka, G.J.; Watkins, D.M.; Kommers, J.M.; Boryschuk, S.J.; Strieby Crouch, A.V.; Kwok, W.K. (Argonne National Lab., IL (USA)); Schirber, J.E.; Overmyer, D.L. (Sandia National Labs., Albuquerque, NM (USA)); Jung, D.; Whangbo, Myunghwan (North Carolina State Univ., Raleigh (USA))

1990-09-05T23:59:59.000Z

455

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

DOE Patents (OSTI)

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

Spahn, Olga B. (Albuquerque, NM); Lear, Kevin L. (Albuquerque, NM)

1998-01-01T23:59:59.000Z

456

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

457

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)

458

Energy Basics: Crystalline Silicon Photovoltaic Cells  

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

(PV) cell's semiconductors. This section describes the atomic structure and bandgap energy of these cells. Atomic Structure All matter is composed of atoms, which are made up of...

459

A Novel Class of High-TC Ferromagnetic Semiconductors  

SciTech Connect

We have grown single crystals of novel ruthenates (Sr,Ba)(Fe,Co){sub 2+x}Ru{sub 4-x}O{sub 11} that exhibit long-range ferromagnetic order well above room temperature, accompanied by narrow-gap semiconducting properties that include a large anomalous Hall conductance, low resistivity, high carrier concentration and low coercive field, which are properties well suited to spintronic applications. X-ray diffraction, EDX, neutron diffraction and x-ray absorption measurements on single crystals firmly establish the 'R-Type' hexagonal ferrite structure (space group P6{sub 3}/mmc, No 194) and single-phase nature of all samples. The electronic structure and physical properties can be tuned by simple chemical substitution of two elements, M = Fe or Co, or by varying the relative concentration of 3d solutes and 4d Ru. Our magnetotransport, x-ray magnetic circular dichroism and magnetic moment data suggest the mechanism for FM order is quite different from that governing known dilute magnetic semiconductors.

Shlyk, L. V.; Kryukov, S. A.; De Long, L. E.; Schupp-Niewa, B.; Niewa, R.; Lynn, J. W.; Huang, Qing; Arenholz, E.; Piamonteze, C.

2008-05-30T23:59:59.000Z

460

Optimal doping control of magnetic semiconductors via subsurfactant epitaxy  

SciTech Connect

Dilute magnetic semiconductors (DMS) with high ferromagnetic ordering temperatures (T{sub c}) have vast potential for advancing spin-based electronics or 'spintronics'. To date, achieving high-T{sub c} DMS typically required doping levels of order 5%. Such high doping levels inevitably compromise the structural homogeneity and carrier mobility of the DMS. Here, we establish 'subsurfactant epitaxy' as a novel kinetic pathway for synthesizing Mn-doped germanium with T{sub c} much higher than room temperature, at dramatically reduced doping levels. This is accomplished by optimal control of the diffusion kinetics of the dopant atoms near the growth front in two separate deposition steps. The first involves a submonolayer dose of Mn on Ge(100) at low temperature, which populates subsurface interstitial sites with Mn while suppressing lateral Mn diffusion and clustering. The second step involves epitaxial growth of Ge at elevated temperature, taking advantage of the strong floating ability of the interstitial Mn dopants towards the newly defined subsurface sites at the growth front. Most remarkably, the Mn dopants trapped inside the film are uniformly distributed at substitutional sites, and the resulting film exhibits ferromagnetism above 400 K at the nominal doping level of only 0.2%.

Zeng, Changgan [ORNL; Zhang, Zhenyu [ORNL; van Benthem, Klaus [ORNL; Chisholm, Matthew F [ORNL; Weitering, Harm H [ORNL

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "wide bandgap 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

Sputter deposition of semiconductor superlattices for thermoelectric applications  

DOE Green Energy (OSTI)

Theoretical dramatic improvement of the thermoelectric properties of materials by using quantum confinement in novel semiconductor nanostructures has lead to considerable interest in the thermoelectric community. Therefore, we are exploring the critical materials issues for fabrication of quantum confined structures by magnetron sputtering in the lead telluride and bismuth telluride families of materials. We have synthesized modulated structures from thermoelectric materials with bilayer periods of as little as 3.2 nm and shown that they are stable at deposition temperatures high enough to grow quality films. Issues critical to high quality film growth have been investigated such as nucleation and growth conditions and their effect on crystal orientation and growth morphology. These investigations show that nucleating the film at a temperature below the growth temperature of optimum electronic properties produces high quality films. Our work with sputter deposition, which is inherently a high rate deposition process, builds the technological base necessary to develop economical production of these advanced materials. High deposition rate is critical since, even if efficiencies comparable with CFC based refrigeration systems can be achieved, large quantities of quantum confined materials will be necessary for cost-competitive uses.

Wagner, A.V.; Foreman, R.J.; Farmer, J.C.; Barbee, T.W.

1996-11-01T23:59:59.000Z

462

Semiconductor grade, solar silicon purification project. Final technical report  

DOE Green Energy (OSTI)

Motorola's low cost poly silicon program is described. In the process, SiF/sub 4/, a low cost by-product is reacted with mg silicon to form SiF/sub 2/ gas which is polymerized. The (SiF/sub 2/)/sub x/ polymer is heated forming volatile Si/sub x/F/sub y/ homologues which disproportionate (C.V.D.) on a silicon particle bed forming silicon and SiF/sub 4/. During the initial phases of the investigation the silicon analysis procedure relied heavily on S.S.M.S. and E.S. analysis. This analysis demonstrated that major purification had occurred and some samples were indistinguishable from semiconductor grade silicon (except possibly for phosphorus). However, more recent electrical analysis via crystal growth reveals that the product contains compensated phosphorus and boron. Work on the control or removal of the electrically active donors and acceptors could yield a product suitable for solar application. The low projected product cost and short energy payback time suggest that the economics of this process will result in a cost less than the J.P.L./D.O.E. goal of $10/Kg (1975 dollars). Finally, assuming a successful demonstration of a pilot facility, the process appears to be readily scalable to a major silicon purification facility as was proposed by Motorola and R. Katzen.

Ingle, W.M.; Rosler, R.S.; Thompson, S.W.; Chaney, R.E.

1979-12-10T23:59:59.000Z

463

Measuring Imputed Costs in the Semiconductor Equipment Supply Chain  

E-Print Network (OSTI)

We consider the order ful¯llment process of a customized capital equipment supplier. Prior to receiving a ¯rm purchase order from the customer, the supplier receives a series of shared forecasts, which are called `soft orders'. Facing a stochastic internal manufacturing lead-time, the supplier must decide at what time to begin the ful¯llment of the order. This decision requires a trade-o ® between starting too early, leading to potential holding or cancellation cost, and the cost of starting too late, leading to potential loss of goodwill. We collect detailed data of shared forecasts, actual purchase orders, production lead-times, and delivery dates for a supplier-buyer dyad in the semiconductor equipment supply chain. Under the assumption that the supplier acts rationally, optimally balancing the cancellation, holding, and delay costs, we are able to estimate the corresponding cost parameters based on the observed data. Our estimation results suggest that the cost of cancellation is four times higher and the holding cost is two times higher than the delay cost. In other words, the supplier is very conservative when commencing the order ful¯llment, which negates the e®ectiveness of the overall forecast sharing mechanism. 1 1

Morris A. Cohen; Teck H. Ho; Justin Z. Ren; Christian Terwiesch

2001-01-01T23:59:59.000Z

464

Cluster Generation Under Pulsed Laser Ablation Of Compound Semiconductors  

SciTech Connect

A comparative experimental study of pulsed laser ablation in vacuum of two binary semiconductors, zinc oxide and indium phosphide, has been performed using IR- and visible laser pulses with particular attention to cluster generation. Neutral and cationic Zn{sub n}O{sub m} and In{sub n}P{sub m} particles of various stoichiometry have been produced and investigated by time-of-flight mass spectrometry. At ZnO ablation, large cationic (n>9) and all neutral clusters are mainly stoichiometric in the ablation plume. In contrast, indium phosphide clusters are strongly indium-rich with In{sub 4}P being a magic cluster. Analysis of the plume composition upon laser exposure has revealed congruent vaporization of ZnO and a disproportionate loss of phosphorus by the irradiated InP surface. Plume expansion conditions under ZnO ablation are shown to be favorable for stoichiometric cluster formation. A delayed vaporization of phosphorus under InP ablation has been observed that results in generation of off-stoichiometric clusters.

Bulgakov, Alexander V.; Evtushenko, Anton B.; Shukhov, Yuri G. [Institute of Thermophysics SB RAS, Lavrentyev Ave. 1, 630090 Novosibirsk (Russian Federation); Ozerov, Igor; Marine, Wladimir [Universite de la Mediterranee, CINaM, UPR CNRS 3118, 13288 Marseille (France)

2010-10-08T23:59:59.000Z

465

Utility-Scale Silicon Carbide Semiconductor: Monolithic Silicon Carbide Anode Switched Thyristor for Medium Voltage Power Conversion  

Science Conference Proceedings (OSTI)

ADEPT Project: GeneSiC is developing an advanced silicon-carbide (SiC)-based semiconductor called an anode-switched thyristor. This low-cost, compact SiC semiconductor conducts higher levels of electrical energy with better precision than traditional silicon semiconductors. This efficiency will enable a dramatic reduction in the size, weight, and volume of the power converters and electronic devices it's used in.GeneSiC is developing its SiC-based semiconductor for utility-scale power converters. Traditional silicon semiconductors can't process the high voltages that utility-scale power distribution requires, and they must be stacked in complicated circuits that require bulky insulation and cooling hardware. GeneSiC's semiconductors are well suited for high-power applications like large-scale renewable wind and solar energy installations.

None

2010-09-01T23:59:59.000Z

466

Stable ohmic contacts to thin films of p-type tellurium-containing II-VI semiconductors  

SciTech Connect

A photovolatic device is described comprising: a light transmissive substrate; an electrically conductive, transparent layer disposed on the substrate as a first electrode; a layer of a first semiconductor disposed on the first electrode; a p-type thin film of a tellurium-containing II-VI semiconductor disposed on the first semiconductor to form a photoresponsive junction with it; and a second electrode contacting the thin film.

Szabo, L.F.; Biter, W.J.

1988-04-05T23:59:59.000Z

467

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

468

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

469

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.

470

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

E-Print Network (OSTI)

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

Ruina, Andy L.

471

The Primary Standards Laboratory (PSL) maintains a wide variety...  

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

Nuclear Security Administration under contract DE-AC04-94AL85000. The Primary Standards Laboratory (PSL) maintains a wide variety of primary thermometry standards to assure...

472

The Primary Standards Laboratory (PSL) maintains a wide variety...  

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

Nuclear Security Administration under contract DE-AC04-94AL85000. The Primary Standards Laboratory (PSL) maintains a wide variety of primary standards to assure accurate...

473

The Primary Standards Laboratory (PSL) maintains a wide variety...  

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

Nuclear Security Administration under contract DE-AC04-94AL85000. The Primary Standards Laboratory (PSL) maintains a wide variety of primary acceleration and shock...

474

Flow Phenomena in an Extra Wide CSP-mold-experimental ...  

Science Conference Proceedings (OSTI)

Presentation Title, Flow Phenomena in an Extra Wide CSP-mold-experimental Investigations. Author(s), Rüdiger Bahrmann, Antje Rückert, Herbert Pfeifer.

475

NREL: Climate Neutral Research Campuses - Campus-Wide Measures...  

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

Campus-Wide Measures Have Greater Potential Pursuing climate neutrality on research campuses fits into the bigger picture of addressing the impacts of climate change and...

476

Effective Community-Wide Policy Technical Assistance: The NREL...  

Open Energy Info (EERE)

NRELDOE Approach Jump to: navigation, search Tool Summary Name: Effective Community-Wide Policy Technical Assistance: The NRELDOE Approach AgencyCompany Organization: National...

477

Draft Site-Wide Environmental Impact Statement Nevada | National...  

National Nuclear Security Administration (NNSA)

> About Us > Our Operations > NNSA Office of General Counsel > National Environmental Policy Act (NEPA) > NEPA Reading Room > Draft Site-Wide Environmental Impact Statement...

478

World-Wide Progress Review on Superconductor Development  

Science Conference Proceedings (OSTI)

Oct 19, 2010 ... Recent Developments in High Temperature Superconductivity: World-Wide ... Superconductivity Efforts at the US Department of Energy (DOE): ...

479

EA-1583: Final Site-wide Environmental Assessment | Department...  

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

Assessment EA-1583: Final Site-wide Environmental Assessment RMOTCNaval Petroleum Reserve No. 3 (October 2008) SUMMARY: The U.S. Departmem of Energy (DOE) is...

480

Sandia National Laboratories Site-Wide Environmental Impact Statement...  

National Nuclear Security Administration (NNSA)

Site-Wide Environmental Impact Statement | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency...

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481

NNSS Final Site-Wide Environmental Impact Statement (SWEIS) ...  

National Nuclear Security Administration (NNSA)

NNSS Final Site-Wide Environmental Impact Statement (SWEIS) | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the...

482

EA-1422: Final Site-wide Environmental Assessment | Department...  

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

Environmental Assessment EA-1422: Final Site-wide Environmental Assessment Sandia National Laboratories Sandia National Laboratories (SNL) is one of three national...

483