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Note: This page contains sample records for the topic "gallium nitride ingan" from the National Library of EnergyBeta (NLEBeta).
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1

Doping of gallium nitride using disilane  

Science Conference Proceedings (OSTI)

Keywords: disilane, gallium nitride, metalorganic chemical vapor deposition, organometallic vapor phase epitaxy, silicon doping

A. E. Wickenden; L. B. Rowland; K. Doverspike; D. K. Gaskill; J. A. Freitas, Jr.; D. S. Simons; P. H. Chi

1995-11-01T23:59:59.000Z

2

Gallium Nitride nanowires: synthesis, contacts, electron ...  

Science Conference Proceedings (OSTI)

... Gallium Nitride nanowires: synthesis, contacts, electron transport, mechanical resonators, and defects. John E. Fischer University of Pennsylvania. ...

3

P-type gallium nitride  

DOE Patents (OSTI)

Several methods have been found to make p-type gallium nitride. P-type gallium nitride has long been sought for electronic devices. N-type gallium nitride is readily available. Discovery of p-type gallium nitride and the methods for making it will enable its use in ultraviolet and blue light-emitting diodes and lasers. pGaN will further enable blue photocathode elements to be made. Molecular beam epitaxy on substrates held at the proper temperatures, assisted by a nitrogen beam of the proper energy produced several types of p-type GaN with hole concentrations of about 5{times}10{sup 11} /cm{sup 3} and hole mobilities of about 500 cm{sup 2} /V-sec, measured at 250 K. P-type GaN can be formed of unintentionally-doped material or can be doped with magnesium by diffusion, ion implantation, or co-evaporation. When applicable, the nitrogen can be substituted with other group III elements such as Al. 9 figs.

Rubin, M.; Newman, N.; Fu, T.; Ross, J.; Chan, J.

1997-08-12T23:59:59.000Z

4

P-type gallium nitride  

DOE Patents (OSTI)

Several methods have been found to make p-type gallium nitride. P-type gallium nitride has long been sought for electronic devices. N-type gallium nitride is readily available. Discovery of p-type gallium nitride and the methods for making it will enable its use in ultraviolet and blue light-emitting diodes and lasers. pGaN will further enable blue photocathode elements to be made. Molecular beam epitaxy on substrates held at the proper temperatures, assisted by a nitrogen beam of the proper energy produced several types of p-type GaN with hole concentrations of about 5.times.10.sup.11 /cm.sup.3 and hole mobilities of about 500 cm.sup.2 /V-sec, measured at 250.degree. K. P-type GaN can be formed of unintentionally-doped material or can be doped with magnesium by diffusion, ion implantation, or co-evaporation. When applicable, the nitrogen can be substituted with other group III elements such as Al.

Rubin, Michael (Berkeley, CA); Newman, Nathan (Montara, CA); Fu, Tracy (Berkeley, CA); Ross, Jennifer (Pleasanton, CA); Chan, James (Berkeley, CA)

1997-01-01T23:59:59.000Z

5

Characterizing organometallic-vapor-phase-epitaxy-grown indium gallium nitride islands on gallium nitride for light emitting diode applications.  

E-Print Network (OSTI)

??The indium-gallium-nitride on gallium-nitride (InGaN/GaN) materials system is a promising candidate for providing a high intensity, high efficiency solution to the yet unsolved problem of… (more)

Anderson, Kathy Perkins Jenkins

2011-01-01T23:59:59.000Z

6

Solar cell with a gallium nitride electrode  

DOE Patents (OSTI)

A solar cell which comprises a body of silicon having a P-N junction therein with a transparent conducting N-type gallium nitride layer as an ohmic contact on the N-type side of the semiconductor exposed to solar radiation.

Pankove, Jacques I. (Princeton, NJ)

1979-01-01T23:59:59.000Z

7

Electrochemical Solution Growth: Gallium Nitride Crystal ...  

... and economical bulk gallium nirtide (GaN) substrates needed to meet the performance requirements of high-efficiency LED and high-power transistors.

8

Size and shape dependence on melting temperature of gallium nitride nanoparticles  

Science Conference Proceedings (OSTI)

The study of variation of the size and shape effect on the melting property of gallium nitride nanoparticles with their spherical and cylindrical geometrical feature is theoretically explored. A numerical thermodynamical model has been devoted for the ...

Paneerselvam Antoniammal; Dakshanamoorthy Arivuoli

2012-01-01T23:59:59.000Z

9

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

10

Compact, Interactive Electric Vehicle Charger: Gallium-Nitride Switch Technology for Bi-directional Battery-to-Grid Charger Applications  

SciTech Connect

ADEPT Project: HRL Laboratories is using gallium nitride (GaN) semiconductors to create battery chargers for electric vehicles (EVs) that are more compact and efficient than traditional EV chargers. Reducing the size and weight of the battery charger is important because it would help improve the overall performance of the EV. GaN semiconductors process electricity faster than the silicon semiconductors used in most conventional EV battery chargers. These high-speed semiconductors can be paired with lighter-weight electrical circuit components, which helps decrease the overall weight of the EV battery charger. HRL Laboratories is combining the performance advantages of GaN semiconductors with an innovative, interactive battery-to-grid energy distribution design. This design would support 2-way power flow, enabling EV battery chargers to not only draw energy from the power grid, but also store and feed energy back into it.

2010-10-01T23:59:59.000Z

11

Current injection efficiency induced efficiency-droop in InGaN quantum well light-emitting diodes  

E-Print Network (OSTI)

Current injection efficiency induced efficiency-droop in InGaN quantum well light-emitting diodes]. The detail of the model for current injection model for quantum well heterostructure is described in Ref. [18 Keywords: III-Nitride InGaN QWs Light-emitting diodes Efficiency-droop a b s t r a c t Current injection

Gilchrist, James F.

12

Low Cost Production of InGaN for Next-Generation Photovoltaic Devices  

SciTech Connect

The goal of this project is to develop a low-cost and low-energy technology for production of photovoltaic devices based on InGaN materials. This project builds on the ongoing development by Structured Materials Industries (SMI), of novel thin film deposition technology for Group III-Nitride materials, which is capable of depositing Group-III nitride materials at significantly lower costs and significantly lower energy usage compared to conventional deposition techniques. During this project, SMI demonstrated deposition of GaN and InGaN films using metalorganic sources, and demonstrated compatibility of the process with standard substrate materials and hardware components.

Nick M. Sbrockey, Shangzhu Sun, Gary S. Tompa,

2012-07-09T23:59:59.000Z

13

Structural TEM study of nonpolar a-plane gallium nitride grown on (112_0) 4H-SiC by organometallic vapor phase epitaxy  

E-Print Network (OSTI)

nitride grown on (1120) 4H-SiC by organometallic vapor phasea-plane GaN grown on a 4H-SiC substrate with an AlN buffergrown on (0001) Al 2 O 3 , 6H-SiC or free- standing GaN

Zakharov, Dmitri N.; Liliental-Weber, Zuzanna; Wagner, Brian; Reitmeier, Zachary J.; Preble, Edward A.; Davis, Robert F.

2005-01-01T23:59:59.000Z

14

Oxidation of gallium arsenide  

DOE Patents (OSTI)

This invention relates to gallium arsenide semiconductors and, more particularly, to the oxidation of surface layers of gallium arsenide semiconductors for semiconductor device fabrication.

Hoffbauer, M.A.; Cross, J.B.

1991-11-16T23:59:59.000Z

15

Secondary ions mass spectroscopy measurements of dopant impurities in highly stressed InGaN laser diodes  

Science Conference Proceedings (OSTI)

We performed a systematic secondary ions mass spectroscopy (SIMS) study of dopant impurities in life-time stressed InGaN laser devices in order to investigate the main degradation mechanism that is observed in nitride laser diodes. A continuous wave (cw) current density of 3 kA/cm{sup 2} was applied to InGaN laser diodes over an extended period of time and we observed the characteristic square root degradation of optical power. We compared the SIMS profiles of Mg, H, and Si impurities in the aged devices and observe that the impurities are remarkably stable over 10 000 h of cw operation. Nor is there any SIMS evidence of p-contact metals penetrating into the semiconductor material. Thus our SIMS results are contrary to what one would expect for impurity diffusion causing the observed square root degradation characteristic.

Marona, L.; Suski, T. [Institute of High Pressure Physics, Sokolowska 29/37, 01-142 Warsaw (Poland); Perlin, P.; Czernecki, R.; Leszczynski, M.; Bockowski, M. [Institute of High Pressure Physics, Sokolowska 29/37, 01-142 Warsaw (Poland); TopGaN Ltd., Sokolowska 29/37, 01-142 Warsaw (Poland); Jakiela, R. [Institute of Physics, al. Lotnikow 32/46, 02-668 Warsaw (Poland); Najda, S. P. [TopGaN Ltd., Sokolowska 29/37, 01-142 Warsaw (Poland)

2011-06-13T23:59:59.000Z

16

Controlling Gallium Nitride Polarity on Native Substrates  

Science Conference Proceedings (OSTI)

Symposium, Advanced Materials for Power Electronics, Power Conditioning, and Power Conversion ... Potential Ceramic Dielectrics for Air Force Applications.

17

Electronic properties of gallium nitride nanowires  

E-Print Network (OSTI)

This thesis presents a systematic study of the electrical transport in GaN nanowires. Particularly, the effect of the surrounding dielectric on the conductivity of GaN nanowires is experimentally shown for the first time. ...

Yoon, Joonah

2008-01-01T23:59:59.000Z

18

Development of gallium nitride power transistors  

E-Print Network (OSTI)

GaN-based high-voltage transistors have outstanding properties for the development of ultra-high efficiency and compact power electronics. This thesis describes a new process technology for the fabrication of GaN power ...

Piedra, Daniel, M. Eng. Massachusetts Institute of Technology

2011-01-01T23:59:59.000Z

19

ICP dry etching of III-V nitrides  

DOE Green Energy (OSTI)

Inductively coupled plasma etching of GaN, AlN, InN, InGaN and InAlN was investigated in CH{sub 4}/H{sub 2}/Ar plasmas as a function of dc bias, and ICP power. The etch rates were generally quite low, as is common for III-nitrides in CH{sub 4} based chemistries. The etch rates increased with increasing dc bias. At low rf power (150 W), the etch rates increased with increasing ICP power, while at 350 W rf power, a peak was found between 500 and 750 W ICP power. The etched surfaces were found to be smooth, while selectivities of etch were {le} 6 for InN over GaN, AlN, InGaN and InAlN under all conditions.

Vartuli, C.B.; Lee, J.W.; MacKenzie, J.D. [Univ. of Florida, Gainesville, FL (United States)] [and others

1997-10-01T23:59:59.000Z

20

Gallium interactions with Zircaloy  

E-Print Network (OSTI)

High fluence ion implantation of Ga ions was conducted ics. on heated Zircaloy-4 in the range of [] Ga ions/[]. Surface effects were studied using SEM and electron microphone analysis. The depth profile of Ga in the Zircaloy was characterized with Rutherford backscattering and SIMS techniques. Results indicate that the Zirc-4 is little affected up to a fluency of [] Ga ions/[]. After implantation of [] Ga ions/[], sub-grain features on the order of 2 gm were observed which may be due to intermetallic compound formation between Ga and Zr. For the highest fluency implant, Ga content in the Zirc-4 reached a saturation value of between 30 and 40 atomic %; significant enhanced diffusion was observed but gallium was not seen to concentrate at grain boundaries.

West, Michael Keith

1998-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "gallium nitride ingan" 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

Electrochemical investigation of the gallium nitride-aqueous electrolyte interface  

SciTech Connect

GaN (E{sub g} = {approximately}3.4 eV) was photoelectrochemically characterized and the energetic position of its bandedges determined with respect to SHE. Electrochemical impedance spectroscopy was employed to analyze the interface, determine the space charge layer capacitance, and, subsequently obtain the flatband potential of GaN in different aqueous electrolytes. The flatband potential of GaN varied at an approximately Nernstian rate in aqueous buffer electrolytes of different pHs indicating acid-base equilibria at the interface.

Kocha, S.S.; Peterson, M.W.; Arent, D.J.; Turner, J.A. [National Renewable Energy Lab., Golden, CO (United States). Photoconversion Branch; Redwing, J.M.; Tischler, M.A. [Advanced Technology Materials, Inc., Danbury, CT (United States)

1995-12-01T23:59:59.000Z

22

Formation mechanisms of spatially-directed zincblende gallium nitride nanocrystals  

Science Conference Proceedings (OSTI)

We report on the spatially selective formation of GaN nanocrystals embedded in GaAs. Broad-area N{sup +} implantation followed by rapid thermal annealing leads to the formation of nanocrystals at the depth of maximum ion damage. With additional irradiation using a Ga{sup +} focused ion beam, selective lateral positioning of the nanocrystals within the GaAs matrix is observed in isolated regions of increased vacancy concentration. Following rapid thermal annealing, the formation of zincblende GaN is observed in the regions of highest vacancy concentration. The nucleation of zincblende nanocrystals over the wurtzite phase of bulk GaN is consistent with the predictions of a thermodynamic model for the nanoscale size-dependence of GaN nucleation.

Wood, A. W. [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109 (United States); Collino, R. R. [Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States); Cardozo, B. L. [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States); Naab, F. [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, Michigan 48109 (United States); Wang, Y. Q. [Materials Science and Technology Division, Los Alamos National Lab, Los Alamos, New Mexico 87545 (United States); Goldman, R. S. [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109 (United States); Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States)

2011-12-15T23:59:59.000Z

23

Nanoscale-Structured Gallium Nitride Pillars for Light-Emitting ...  

Science Conference Proceedings (OSTI)

... using top-down fabrication scheme, D. Paramanik, A. Motayed, GS Aluri, J.-Y. Ha, S. Krylyuk, AV Davydov, M. King, S. McLaughlin, S. Gupta, and H ...

2013-01-18T23:59:59.000Z

24

Nanofabrication of gallium nitride photonic crystal light-emitting diodes  

Science Conference Proceedings (OSTI)

We describe a comparison of nanofabrication technologies for the fabrication of 2D photonic crystal structures on GaN/InGaN blue LEDs. Such devices exhibit enhanced brightness and the possibility of controlling the angular emission profile of emitted ... Keywords: GaN dry-etching, Light-emitting diodes, Nanolithography, Photonic crystals

Ali Z. Khokhar; Keith Parsons; Graham Hubbard; Faiz Rahman; Douglas S. Macintyre; Chang Xiong; David Massoubre; Zheng Gong; Nigel P. Johnson; Richard M. De La Rue; Ian M. Watson; Erdan Gu; Martin D. Dawson; Steve J. Abbott; Martin D. B. Charlton; Martin Tillin

2010-11-01T23:59:59.000Z

25

Preparation of uranium nitride  

DOE Patents (OSTI)

A process for preparing actinide-nitrides from massive actinide metal which is suitable for sintering into low density fuel shapes by partially hydriding the massive metal and simultaneously dehydriding and nitriding the dehydrided portion. The process is repeated until all of the massive metal is converted to a nitride.

Potter, Ralph A. (Lynchburg, VA); Tennery, Victor J. (Upper Arlington, OH)

1976-01-01T23:59:59.000Z

26

Plasma chemistries for dry etching GaN, AlN, InGaN and InAlN  

DOE Green Energy (OSTI)

Etch rates up to 7,000 {angstrom}/min. for GaN are obtained in Cl{sub 2}/H{sub 2}/Ar or BCl{sub 3}/Ar ECR discharges at 1--3mTorr and moderate dc biases. Typical rates with HI/H{sub 2} are about a factor of three lower under the same conditions, while CH{sub 4}/H{sub 2} produces maximum rates of only {approximately}2,000 {angstrom}/min. The role of additives such as SF{sub 6}, N{sub 2}, H{sub 2} or Ar to the basic chlorine, bromine, iodine or methane-hydrogen plasma chemistries are discussed. Their effect can be either chemical (in forming volatile products with N) or physical (in breaking bonds or enhancing desorption of the etch products). The nitrides differ from conventional III-V`s in that bond-breaking to allow formation of the etch products is a critical factor. Threshold ion energies for the onset of etching of GaN, InGaN and InAlN are {ge} 75 eV.

Pearton, S.J.; Vartuli, C.B.; Lee, J.W.; Donovan, S.M.; MacKenzie, J.D.; Abernathy, C.R. [Univ. of Florida, Gainesville, FL (United States); Shul, R.J. [Sandia National Labs., Albuquerque, NM (United States); McLane, G.F. [Army Research Lab., Fort Monmouth, NJ (United States); Ren, F. [AT and T Bell Labs., Murray Hill, NJ (United States)

1996-04-01T23:59:59.000Z

27

Session GG: III-Nitrides  

Science Conference Proceedings (OSTI)

Jun 24, 2011 ... Long-wavelength light emitting diode (LED) structures were grown on top of partially relaxed InGaN layers, resulting in reduced strain in the ...

28

Ingan Based True Green Laser Diodes on Novel Semi-Polar {20-21}  

Science Conference Proceedings (OSTI)

In this paper, we present the high crystal quality and homogeneity in InGaN quantum wells (QWs) on {20-21} planes with the 531 nm true green pulsed lasing  ...

29

Synthesis, characterization, and biotemplated assembly of indium nitride and indium gallium nitride nanoparticles  

E-Print Network (OSTI)

A low-temperature, ambient pressure solution synthesis of colloidal InN nanoparticles is presented. This synthesis utilizes a previously dismissed precursor and results in individual, non-aggregated nanoparticles with ...

Hsieh, Jennifer Chia-Jen

2010-01-01T23:59:59.000Z

30

Nitride fuel performance  

E-Print Network (OSTI)

The purpose of this work was to assess the potential of nitride fuels in the current context of the nuclear industry. Nitride fuels systems have indeed been for the past decade the subject of new interest from the international community. This renewal of interest can be explained by the strong potential that nitride fuel systems exhibit for applications such as advanced fast reactor technology, waste transmutation and nuclear space power. To assess this potential, a review of the nitride physical properties was performed in comparison to oxide or metal fuel properties. The potential applications of nitride systems were also detailed. A fuel performance computer code was developed to obtain a more quantitative comparison between nitride and oxide fuel. The oxide code FUELROD was taken as a basis for the new code. After modernization, nitride fuel property correlations were implemented to obtain a nitride version of the code. Using this new tool, a comparison between oxide and nitride fuels was performed to highlight their difference in irradiation behavior in order to confirm their potential.

Reynaud, Sylvie Marie Aurel?ie

2002-01-01T23:59:59.000Z

31

Synthesis and characterization of visible emission from rare-earth doped aluminum nitride, gallium nitride and gallium aluminum nitride powders and thin films  

E-Print Network (OSTI)

to improve sealing and prevent the ingress of air, as shownimproved sealing and prevented the ingress of air, which

Tao, Jonathan Huai-Tse

2010-01-01T23:59:59.000Z

32

Superconducting structure with layers of niobium nitride and aluminum nitride  

DOE Patents (OSTI)

A superconducting structure is formed by depositing alternate layers of aluminum nitride and niobium nitride on a substrate. Deposition methods include dc magnetron reactive sputtering, rf magnetron reactive sputtering, thin-film diffusion, chemical vapor deposition, and ion-beam deposition. Structures have been built with layers of niobium nitride and aluminum nitride having thicknesses in a range of 20 to 350 Angstroms. Best results have been achieved with films of niobium nitride deposited to a thickness of approximately 70 Angstroms and aluminum nitride deposited to a thickness of approximately 20 Angstroms. Such films of niobium nitride separated by a single layer of aluminum nitride are useful in forming Josephson junctions. Structures of 30 or more alternating layers of niobium nitride and aluminum nitride are useful when deposited on fixed substrates or flexible strips to form bulk superconductors for carrying electric current. They are also adaptable as voltage-controlled microwave energy sources. 8 figs.

Murduck, J.M.; Lepetre, Y.J.; Schuller, I.K.; Ketterson, J.B.

1989-07-04T23:59:59.000Z

33

Decreased gallium uptake in acute hematogenous osteomyelitis  

SciTech Connect

Decreased radiopharmaceutical uptake was noted on both bone and gallium scans in the case of acute hematogenous osteomyelitis of the right ilium (acetabular roof). This combination of findings is probably rare. The mechanism of decreased gallium uptake is unknown, but may be related to decreased blood flow.

Ang, J.G.; Gelfand, M.J.

1983-07-01T23:59:59.000Z

34

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

35

Boron nitride nanotubes  

Science Conference Proceedings (OSTI)

Boron nitride nanotubes are prepared by a process which includes: (a) creating a source of boron vapor; (b) mixing the boron vapor with nitrogen gas so that a mixture of boron vapor and nitrogen gas is present at a nucleation site, which is a surface, the nitrogen gas being provided at a pressure elevated above atmospheric, e.g., from greater than about 2 atmospheres up to about 250 atmospheres; and (c) harvesting boron nitride nanotubes, which are formed at the nucleation site.

Smith, Michael W. (Newport News, VA); Jordan, Kevin (Newport News, VA); Park, Cheol (Yorktown, VA)

2012-06-06T23:59:59.000Z

36

A3, Depth Resolved Strain and Composition Studies on InGaN and ...  

Science Conference Proceedings (OSTI)

... devices due to its large spontaneous polarization and conduction band offset. ... 620°C with fixed beam fluxes of In and Ga under the same nitrogen plasma condition. ... Inexpensive, Non-Toxic Thermoelectric Materials for Waste Heat Recovery ..... Y5, Defect Characterization of InGaN Layer by Deep Level Transient and ...

37

Luminescence Enhancement in InGaN and ZnO by Water Vapor ...  

Science Conference Proceedings (OSTI)

Dependence of Ag/In Ratio of AgInS2 Crystals Grown by Hot-Press Method ... Analysis of Temperature Characteristics of InGaP/InGaAs/Ge Triple-Junction Solar Cell ... Luminescence Enhancement in InGaN and ZnO by Water Vapor Remote ...

38

Surface plasmon enhanced InGaN light emitter Koichi Okamoto*a  

E-Print Network (OSTI)

is a very promising method for developing the super bright light emitting diodes (LEDs). Moreover, we foundGaN/GaN, light emitting diode, quantum well, internal quantum efficiency, solid-state light source 1. INTRODUCTION Since 1993, InGaN quantum wells (QW)-based light emitting diodes (LEDs) have been continuously

Okamoto, Koichi

39

Enhancement of Radiative Efficiency with Staggered InGaN Quantum Well Light Emitting Diodes  

SciTech Connect

The technology on the large overlap InGaN QWs developed in this program is currently implemented in commercial technology in enhancing the internal quantum efficiency in major LED industry in US and Asia. The scientific finding from this work supported by the DOE enabled the implementation of this step-like staggered quantum well in the commercial LEDs.

Tansu, Nelson; Dierolf, Volkmar; Huang, Gensheng; Penn, Samson; Zhao, Hongping; Liu, Guangyu; Li, Xiaohang; Poplawsky, Jonathan

2011-07-14T23:59:59.000Z

40

Cubic nitride templates  

DOE Patents (OSTI)

A polymer-assisted deposition process for deposition of epitaxial cubic metal nitride films and the like is presented. The process includes solutions of one or more metal precursor and soluble polymers having binding properties for the one or more metal precursor. After a coating operation, the resultant coating is heated at high temperatures under a suitable atmosphere to yield metal nitride films and the like. Such films can be used as templates for the development of high quality cubic GaN based electronic devices.

Burrell, Anthony K; McCleskey, Thomas Mark; Jia, Quanxi; Mueller, Alexander H; Luo, Hongmei

2013-04-30T23:59:59.000Z

Note: This page contains sample records for the topic "gallium nitride ingan" 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

Coincident site lattice-matched InGaN on (111) spinel substrates  

Science Conference Proceedings (OSTI)

Coincident site lattice-matched wurtzite (0001) In{sub 0.31}Ga{sub 0.69}N, emitting in the important green wavelength region, is demonstrated by molecular beam epitaxy on a cubic (111) MgAl{sub 2}O{sub 4} spinel substrate. The coincident site lattice matching condition involves a 30 deg. rotation between the lattice of the InGaN epitaxial layer and the lattice of the spinel. This work describes an alternative approach towards realizing more compositionally homogenous InGaN films with low dislocation density emitting in the ''green gap'' of low efficiency currently observed for semiconductor light emitting diodes (LEDs). This approach could lead to higher efficiency green LEDs presently of great interest for solid-state lighting applications.

Norman, A. G.; Dippo, P. C.; Moutinho, H. R.; Simon, J.; Ptak, A. J. [National Renewable Energy Laboratory, Golden, Colorado 80401 (United States)

2012-04-09T23:59:59.000Z

42

Coincident Site Lattice Matched InGaN on (111) Spinel Substrates  

Science Conference Proceedings (OSTI)

Coincident site lattice-matched wurtzite (0001) In{sub 0.31}Ga{sub 0.69}N, emitting in the important green wavelength region, is demonstrated by molecular beam epitaxy on a cubic (111) MgAl{sub 2}O{sub 4} spinel substrate. The coincident site lattice matching condition involves a 30{sup o} rotation between the lattice of the InGaN epitaxial layer and the lattice of the spinel. This work describes an alternative approach towards realizing more compositionally homogenous InGaN films with low dislocation density emitting in the 'green gap' of low efficiency currently observed for semiconductor light emitting diodes (LEDs). This approach could lead to higher efficiency green LEDs presently of great interest for solid-state lighting applications.

Norman, A. G.; Dippo, P. C.; Moutinho, H. R.; Simon, J.; Ptak, A. J.

2012-04-09T23:59:59.000Z

43

Growth and optical characterization of multilayers of InGaN quantum dots  

E-Print Network (OSTI)

(QDs) have recently attracted much attention for a variety of optoelectronic applications and for exploration of their fundamental physics [1] . By using a high density of uniformly distributed self-assembled QDs, laser diodes (LDs) have been r... [ 11] and microdisks [ 12] , which allows more efficient light extraction from the QD layer. In this paper, we investigated the growth of multilayers of InGaN QDs using the modified droplet epitaxy approach. It is hoped that this could lead...

Zhu, Tontong; El-Ella, Haitham; Reid, Benjamin; Holmes, Mark; Taylor, Robert; Kappers, Menno; Oliver, Rachel

2012-01-01T23:59:59.000Z

44

Method for Plutonium-Gallium Separation by Anodic Dissolution of a Solid Plutonium-Gallium Alloy  

DOE Patents (OSTI)

Purified plutonium and gallium are efficiently recovered from a solid plutonium-gallium (Pu-Ga) alloy by using an electrorefining process. The solid Pu-Ga alloy is the cell anode, preferably placed in a moving basket within the electrolyte. As the surface of the Pu-Ga anode is depleted in plutonium by the electrotransport of the plutonium to a cathode, the temperature of the electrolyte is sufficient to liquify the surface, preferably at about 500 C, resulting in a liquid anode layer substantially comprised of gallium. The gallium drips from the liquified surface and is collected below the anode within the electrochemical cell. The transported plutonium is collected on the cathode surface and is recovered.

Miller, William E.; Tomczuk, Zygmunt

1998-12-08T23:59:59.000Z

45

Session II: Intersubband Devices: AlInN and InGaN Materials ...  

Science Conference Proceedings (OSTI)

Jun 24, 2011 ... However, the numerous experimental attempts to study the vertical transport in the III-Nitride thin film resonant tunneling diodes (RTD) haven't ...

46

Gallium-positive Lyme disease myocarditis  

Science Conference Proceedings (OSTI)

In the course of a work-up for fever of unknown origin associated with intermittent arrhythmias, a gallium scan was performed which revealed diffuse myocardial uptake. The diagnosis of Lyme disease myocarditis subsequently was confirmed by serologic titers. One month following recovery from the acute illness, the abnormal myocardial uptake completely resolved.

Alpert, L.I.; Welch, P.; Fisher, N.

1985-09-01T23:59:59.000Z

47

Superplastic forging nitride ceramics  

DOE Patents (OSTI)

The invention relates to producing relatively flaw free silicon nitride ceramic shapes requiring little or no machining by superplastic forging This invention herein was made in part under Department of Energy Grant DE-AC01-84ER80167, creating certain rights in the United States Government. The invention was also made in part under New York State Science and Technology Grant SB1R 1985-10.

Panda, Prakash C. (Ithaca, NY); Seydel, Edgar R. (Ithaca, NY); Raj, Rishi (Ithaca, NY)

1988-03-22T23:59:59.000Z

48

Gallium 67 scintigraphy in glomerular disease  

Science Conference Proceedings (OSTI)

To evaluate the diagnostic usefulness of gallium 67 scintigraphy in glomerular disease, 45 patients with various glomerulopathies, excluding lupus nephritis and renal vasculitis, were studied. Persistent renal visualization 48 hours after the gallium injection, a positive scintigram, was graded as + (less than), ++ (equal to), and +++ (greater than) the hepatic uptake. Positive scintigrams were seen in ten of 16 cases of focal segmental glomerulosclerosis, six of 11 cases of proliferative glomerulonephritis, and one case of minimal change, and one of two cases of membranous nephropathy; also in three of six cases of sickle glomerulopathy, two cases of diabetic neuropathy, one of two cases of amyloidosis, and one case of mild chronic allograft rejection. The 25 patients with positive scans were younger than the 20 with negative scans (31 +/- 12 v 42 +/- 17 years; P less than 0.01), and exhibited greater proteinuria (8.19 +/- 7.96 v 2.9 +/- 2.3 S/d; P less than 0.01) and lower serum creatinine values (2 +/- 2 v 4.1 +/- 2.8 mg/dL; P less than 0.01). The amount of proteinuria correlated directly with the intensity grade of the gallium image (P less than 0.02), but there was no correlation between the biopsy diagnosis and the outcome of the gallium scan. It was concluded that gallium scintigraphy is not useful in the differential diagnosis of the glomerular diseases under discussion. Younger patients with good renal function and heavy proteinuria are likely to have a positive renal scintigram regardless of the underlying glomerulopathy.

Bakir, A.A.; Lopez-Majano, V.; Levy, P.S.; Rhee, H.L.; Dunea, G.

1988-12-01T23:59:59.000Z

49

Silicon nitride ceramic comprising samaria and ytterbia  

Science Conference Proceedings (OSTI)

This invention relates to a sintered silicon nitride ceramic comprising samaria and ytterbia for enhanced toughness.

Yeckley, Russell L. (Oakham, MA)

1996-01-01T23:59:59.000Z

50

Controlled VLS Growth of Indium, Gallium and Tin Oxide Nanowires via Chemical Vapor Transport  

E-Print Network (OSTI)

technique to synthesize indium oxide, gallium oxide, and tinmaterial systems such as indium oxide, gallium oxide and tinand Characterization A. Indium Oxide Nanowires Indium oxide

Johnson, M.C.; Aloni, S.; McCready, D.E.; Bourret-Courchesne, E.D.

2006-01-01T23:59:59.000Z

51

Survey of the market, supply and availability of gallium  

DOE Green Energy (OSTI)

The objective of this study was to assess the present consumption and supply of gallium, its potential availability in the satellite power system (SPS) implementation time frame, and commercial and new processing methods for increasing the production of gallium. Findings are reported in detail. The findings strongly suggest that with proper long range planning adequate gallium would be available from free-enterprise world supplies of bauxite for SPS implementation.

Rosi, F.D.

1980-07-01T23:59:59.000Z

52

Interactions of Zircaloy cladding with gallium: 1998 midyear status  

Science Conference Proceedings (OSTI)

A program has been implemented to evaluate the effect of gallium in mixed-oxide (MOX) fuel derived from weapons-grade (WG) plutonium on Zircaloy cladding performance. The objective is to demonstrate that low levels of gallium will not compromise the performance of the MOX fuel system in a light-water reactor. The graded, four-phase experimental program was designed to evaluate the performance of prototypic Zircaloy cladding materials against (1) liquid gallium (Phase 1), (2) various concentrations of Ga{sub 2}O{sub 3} (Phase 2), (3) centrally heated surrogate fuel pellets with expected levels of gallium (Phase 3), and (4) centrally heated prototypic MOX fuel pellets (Phase 4). This status report describes the results of a series of tests for Phases 1 and 2. Three types of tests are being performed: (1) corrosion, (2) liquid metal embrittlement, and (3) corrosion-mechanical. These tests will determine corrosion mechanisms, thresholds for temperature and concentration of gallium that may delineate behavioral regimes, and changes in the mechanical properties of Zircaloy. Initial results have generally been favorable for the use of WG-MOX fuel. The MOX fuel cladding, Zircaloy, does react with gallium to form intermetallic compounds at {ge}300 C; however, this reaction is limited by the mass of gallium and is therefore not expected to be significant with a low level (parts per million) of gallium in the MOX fuel. Although continued migration of gallium into the initially formed intermetallic compound can result in large stresses that may lead to distortion, this was shown to be extremely unlikely because of the low mass of gallium or gallium oxide present and expected clad temperatures below 400 C. Furthermore, no evidence for grain boundary penetration by gallium has been observed.

Wilson, D.F.; DiStefano, J.R.; Strizak, J.P.; King, J.F.; Manneschmidt, E.T.

1998-06-01T23:59:59.000Z

53

Interactions of zircaloy cladding with gallium -- 1997 status  

SciTech Connect

A four phase program has been implemented to evaluate the effect of gallium in mixed oxide (MOX) fuel derived from weapons grade (WG) plutonium on Zircaloy cladding performance. The objective is to demonstrate that low levels of gallium will not compromise the performance of the MOX fuel system in LWR. This graded, four phase experimental program will evaluate the performance of prototypic Zircaloy cladding materials against: (1) liquid gallium (Phase 1), (2) various concentrations of Ga{sub 2}O{sub 3} (Phase 2), (3) centrally heated surrogate fuel pellets with expected levels of gallium (Phase 3), and (4) centrally heated prototypic MOX fuel pellets (Phase 4). This status report describes the results of an initial series of tests for phases 1 and 2. Three types of tests are being performed: (1) corrosion, (2) liquid metal embrittlement (LME), and (3) corrosion mechanical. These tests are designed to determine the corrosion mechanisms, thresholds for temperature and concentration of gallium that may delineate behavioral regimes, and changes in mechanical properties of Zircaloy. Initial results have generally been favorable for the use of WG-MOX fuel. The MOX fuel cladding, Zircaloy, does react with gallium to form intermetallic compounds at {ge} 300 C; however, this reaction is limited by the mass of gallium and is therefore not expected to be significant with a low level (in parts per million) of gallium in the MOX fuel. While continued migration of gallium into the initially formed intermetallic compound results in large stresses that can lead to distortion, this is also highly unlikely because of the low mass of gallium or gallium oxide present and expected clad temperatures below 400 C. Furthermore, no evidence for grain boundary penetration by gallium has been observed.

Wilson, D.F.; DiStefano, J.R.; King, J.F.; Manneschmidt, E.T.; Strizak, J.P.

1997-11-01T23:59:59.000Z

54

Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide...  

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

Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Low-dimensional materials have gained much attention not only because of the nonstop march toward...

55

Gallium uptake by transferrin and interaction with receptor 1  

Science Conference Proceedings (OSTI)

Iron acquisition Á Gallium uptake Á Temperature-jump kinetics .... Part of this thera- peutic action is ..... are all considered as hard metals [10] and are com-.

56

Cold Atoms Could Replace Hot Gallium in Focused Ion ...  

Science Conference Proceedings (OSTI)

... The high energies needed to focus gallium for milling tasks end up burying small amounts in the sample, contaminating the material. ...

2011-04-26T23:59:59.000Z

57

Interactions of gallium with zircaloy cladding  

E-Print Network (OSTI)

A mastering system was constructed and installed on the current low energy accelerator of the Ion Beam Laboratory in the Department of Nuclear Engineering. Galium was implanted into heated zircaloy targets at nuances of 3x10ą?, 1x10ą? and 1x10ą? ions/cm˛. Rutherford backscattering spectrometry (RBS) using 260 keV alpha particles was used to determine the initial estimates of gallium concentration. Energy dispersive spectroscopy (EDS) and backscattered electron (BSE) imaging was performed to examine concentration and surface morphology, respectively. Zirconium was then implanted to simulate the radiation effects of fission fragments at a fluency of 1.0x10ą? Zr atoms/cm˛. RBS results showed enhanced diffusion and indicate saturation of the gallium concentration. Results also showed the possible formation of a Ga-Zr compound.

Mitchell, Lee Josey

1999-01-01T23:59:59.000Z

58

Growth and morphology of 0.80 eV photoemitting indium nitride nanowires  

DOE Green Energy (OSTI)

InN nanowires with high efficiency photoluminescence emission at 0.80 eV are reported for the first time. InN nanowires were synthesized via a vapor solid growth mechanism from high purity indium metal and ammonia. The products consist of only hexagonal wurtzite phase InN. Scanning electron microscopy showed wires with diameters of 50-100nm and having fairly smooth morphologies. High-resolution transmission electron microscopy revealed high quality, single crystal InN nanowires which grew in the <0001> direction. The group-III nitrides have become an extremely important technological material over the past decade. They are commonly used in optoelectronic devices, such as high brightness light-emitting diodes (LEDs) and low wavelength laser diodes (LDs), as well as high power/high frequency electronic devices. Recently InN thin films grown by MOCVD and MBE were found to have a bandgap energy in the range of 0.7-0.9 eV, much lower than the value of {approx}1.9 eV found for InN films grown by sputtering. This large decrease in the direct bandgap transition energy and the ability to form ternary (InGaN) and quaternary (AlInGaN) alloys increases the versatility of group-III nitride optoelectronic devices, ranging from the near IR to the UV. Additionally, InN has some promising transport and electronic properties. It has the smallest effective electron mass of all the group-III nitrides which leads to high mobility and high saturation velocity10 and a large drift velocity at room temperature. As a result of these unique properties, there has been a large increase in interest in InN for potential use in optoelectronic devices, such as LDs and high efficiency solar cells, as well as high frequency/high power electronic devices.

Johnson, M.C.; Lee, C.J.; Bourret-Courchesne, E.D.; Konsek, S.L.; Aloni, S.; Han, W.Q.; Zettl, A.

2004-08-13T23:59:59.000Z

59

The Hybridization of CdSe/ZnS Quantum Dot on InGaN Light-Emitting Diodes for Color Conversion  

Science Conference Proceedings (OSTI)

We have demonstrated the fabrication and characterization of hybrid CdSe/ZnS quantum dot (QD)-InGaN blue LEDs. The chemically synthesized red light (lambda = 623 nm) QD solutions with different concentrations were dropped onto the blue InGaN LEDs with ... Keywords: CdSe/ZnS quantum dots, CdSe/ZnS quantum dots (QDs), InGaN quantum well and hybrid LEDs, InGaN quantum well and hybrid light-emitting diodes

Ying-Chih Chen; Chun-Yuan Huang; Yan-Kuin Su; Wen-Liang Li; Chia-Hsien Yeh; Yu-Cheng Lin

2008-07-01T23:59:59.000Z

60

Hard carbon nitride and method for preparing same  

DOE Patents (OSTI)

Novel crystalline .alpha. (silicon nitride-like)-carbon nitride and .beta. (silicon nitride-like)-carbon nitride are formed by sputtering carbon in the presence of a nitrogen atmosphere onto a single crystal germanium or silicon, respectively, substrate.

Haller, Eugene E. (Berkeley, CA); Cohen, Marvin L. (Berkeley, CA); Hansen, William L. (Walnut Creek, CA)

1992-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "gallium nitride ingan" 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

Cordierite silicon nitride filters  

SciTech Connect

The objective of this project was to develop a silicon nitride based crossflow filter. This report summarizes the findings and results of the project. The project was phased with Phase I consisting of filter material development and crossflow filter design. Phase II involved filter manufacturing, filter testing under simulated conditions and reporting the results. In Phase I, Cordierite Silicon Nitride (CSN) was developed and tested for permeability and strength. Target values for each of these parameters were established early in the program. The values were met by the material development effort in Phase I. The crossflow filter design effort proceeded by developing a macroscopic design based on required surface area and estimated stresses. Then the thermal and pressure stresses were estimated using finite element analysis. In Phase II of this program, the filter manufacturing technique was developed, and the manufactured filters were tested. The technique developed involved press-bonding extruded tiles to form a filter, producing a monolithic filter after sintering. Filters manufactured using this technique were tested at Acurex and at the Westinghouse Science and Technology Center. The filters did not delaminate during testing and operated and high collection efficiency and good cleanability. Further development in areas of sintering and filter design is recommended.

Sawyer, J.; Buchan, B. (Acurex Environmental Corp., Mountain View, CA (United States)); Duiven, R.; Berger, M. (Aerotherm Corp., Mountain View, CA (United States)); Cleveland, J.; Ferri, J. (GTE Products Corp., Towanda, PA (United States))

1992-02-01T23:59:59.000Z

62

Method for producing refractory nitrides  

DOE Patents (OSTI)

Disclosed is a process for making fine, uniform metal nitride powders that can be hot pressed or sintered. A metal salt is placed in a solvent with Melamine and warmed until a metal-Melamine compound forms. The solution is cooled and the metal-Melamine precipitate is calcined at a temperature below 700/sup 0/C to form the metal nitrides and to avoid formation of the metal oxide.

Quinby, T.C.

1986-04-09T23:59:59.000Z

63

Bright Lights and Even Brighter Ideas | Department of Energy  

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

Bright Lights and Even Brighter Ideas Bright Lights and Even Brighter Ideas Bright Lights and Even Brighter Ideas July 3, 2013 - 2:04pm Addthis Kim Kisslinger, a researcher at Brookhaven Lab's Center for Functional Nanomaterials seen here with a focused-ion beam instrument, reduced the indium gallium nitride (InGaN) samples to a thickness of just 20 nanometers to prepare them for electron microscopy. | Photo courtesy of Brookhaven National Laboratory. Kim Kisslinger, a researcher at Brookhaven Lab's Center for Functional Nanomaterials seen here with a focused-ion beam instrument, reduced the indium gallium nitride (InGaN) samples to a thickness of just 20 nanometers to prepare them for electron microscopy. | Photo courtesy of Brookhaven National Laboratory. Charles Rousseaux Charles Rousseaux

64

Structure and electronic properties of saturated and unsaturated gallium nitride nanotubes  

DOE Green Energy (OSTI)

The atomic and electronic structures of saturated and unsaturated GaN nanotubes along the [001] direction with (100) lateral facets are studied using first-principles calculations. Atomic relaxation of nanotubes shows that appreciable distortion occurs in the unsaturated nanotubes. All the nanotubes considered, including saturated and unsaturated ones, exhibit semiconducting, with a direct band gap. Surface states arisen from the threefold-coordinated N and Ga atoms at the lateral facets exist inside the bulk-like band gap. When the nanotubes saturated with hydrogen, these dangling bond bands are removed from the band gap, but the band gap decreases with increasing the wall thickness of the nanotubes.

Wang, Zhiguo; Wang, Shengjie; Li, Jingbo; Gao, Fei; Weber, William J.

2009-11-05T23:59:59.000Z

65

Diffusion, Uptake and Release of Hydrogen in p-type Gallium Nitride: Theory and Experiment  

DOE Green Energy (OSTI)

The diffusion, uptake, and release of H in p-type GaN are modeled employing state energies from density-function theory and compared with measurements of deuterium uptake and release using nuclear-reaction analysis. Good semiquantitative agreement is found when account is taken of a surface permeation barrier.

MYERS JR.,SAMUEL M.; WRIGHT,ALAN F.; PETERSEN,GARY A.; WAMPLER,WILLIAM R.; SEAGER,CARLETON H.; CRAWFORD,MARY H.; HAN,JUNG

2000-06-27T23:59:59.000Z

66

The equilibrium state of hydrogen in gallium nitride: Theory and experiment  

DOE Green Energy (OSTI)

Formation energies and vibrational frequencies for H in wurtzite GaN were calculated from density functional theory and used to predict equilibrium state occupancies and solid solubilities for p-type, intrinsic, and n-type material. The solubility of deuterium (D) was measured at 600--800 C as a function of D{sub 2} pressure and doping and compared with theory. Agreement was obtained by reducing the H formation energies 0.2 eV from ab-initio theoretical values. The predicted stretch-mode frequency for H bound to the Mg acceptor lies 5% above an observed infrared absorption attributed to this complex. It is concluded that currently recognized H states and physical processes account for the equilibrium behavior of H examined in this work.

MYERS JR.,SAMUEL M.; WRIGHT,ALAN F.; PETERSEN,GARY A.; SEAGER,CARLETON H.; WAMPLER,WILLIAM R.; CRAWFORD,MARY H.; HAN,JUNG

2000-04-17T23:59:59.000Z

67

Radiation-Hardened Gallium Nitride Detector and Arrays for Fusion Diagnostics  

Science Conference Proceedings (OSTI)

This poster reports testing to confirm that GaN devices exhibit the extreme radiation hardness needed for use at the NIF, functioning properly after 1x10{sup 12} protons/cm{sup 2} proton irradiation in one year.

Sun, K. X., and MacNeil, L.

2011-09-08T23:59:59.000Z

68

Commercialization of gallium nitride nanorod arrays on silicon for solid-state lighting  

E-Print Network (OSTI)

One important component in energy usage is lighting, which is currently dominated by incandescent and fluorescent lamps. However, due to potentially higher efficiencies and thus higher energy savings, solid-state lighting ...

Wee, Qixun

2008-01-01T23:59:59.000Z

69

Behavior of Zircaloy Cladding in the Presence of Gallium  

Science Conference Proceedings (OSTI)

The U.S. Department of Energy has established a dual-track approach to the disposition of plutonium arising from the dismantling of nuclear weapons. Both immobilization and reactor-based mixed-oxide (MOX) fuel technologies are being evaluated. The reactor-based MOX fuel option requires assessment of the potential impact of concentrations of gallium (on the order of 1 to 10 ppm), not present in conventional MOX fuel, on cladding material performance. An experimental program was designed to evaluate the performance of prototypic Zircaloy cladding materials against (1) liquid gallium, and (2) various concentrations of G~03. Three types of tests were performed: (1) corrosion, (2) liquid metal embrittlement, and (3) corrosion-mechanical. These tests were to determine corrosion mechanisms, thresholds for temperature and concentration of gallium that delineate behavioral regimes, and changes in the mechanical properties of Zircaloy. Results have generally been favorable for the use of weapons-grade (WG) MOX fhel. The Zircaloy cladding does react with gallium to form intermetallic compounds at >3000 C; however, this reaction is limited by the mass of gallium and is therefore not expected to be significant with a low level (parts per million) of gallium in the MOX fuel. Furthermore, no evidence for grain boundary penetration by gallium or liquid metal embrittlement was observed.

DiStefano, J.R.; King, J.F.; Manneschmidt, E.T.; Strizak, J.P.; Wilson, D.F.

1998-09-28T23:59:59.000Z

70

Process for making transition metal nitride whiskers  

DOE Patents (OSTI)

A process for making metal nitrides, particularly titanium nitride whiskers, using a cyanide salt as a reducing agent for a metal compound in the presence of an alkali metal oxide. Sodium cyanide, various titanates and titanium oxide mixed with sodium oxide react to provide titanium nitride whiskers that can be used as reinforcement to ceramic composites. 1 fig., 1 tab.

Bamberger, C.E.

1988-04-12T23:59:59.000Z

71

Improved InGaN epitaxy yield by precise temperature measurement :yearly report 1.  

SciTech Connect

This Report summarizes the first year progress (October 1, 2004 to September 30, 2005) made under a NETL funded project entitled ''Improved InGaN Epitaxy Yield by Precise Temperature Measurement''. This Project addresses the production of efficient green LEDs, which are currently the least efficient of the primary colors. The Project Goals are to advance IR and UV-violet pyrometry to include real time corrections for surface emissivity on multiwafer MOCVD reactors. Increasing wafer yield would dramatically reduce high brightness LED costs and accelerate the commercial manufacture of inexpensive white light LEDs with very high color quality. This work draws upon and extends our previous research (funded by DOE) that developed emissivity correcting pyrometers (ECP) based on the high-temperature GaN opacity near 400 nm (the ultraviolet-violet range, or UVV), and the sapphire opacity in the mid-IR (MIR) near 7.5 microns.

Koleske, Daniel David; Creighton, James Randall; Russell, Michael J.; Fischer, Arthur Joseph

2006-08-01T23:59:59.000Z

72

Interactions of Zircaloy Cladding with Gallium: Final Report  

Science Conference Proceedings (OSTI)

The U.S. Department of Energy has established a dual-track approach to the disposition of plutonium arising from the dismantling of nuclear weapons. Both immobilization and reactor-based mixed-oxide (MOX) fuel technologies are being evaluated. The reactor-based MOX fuel option requires assessment of the potential impact of concentrations of gallium (on the order of 1 to 10 ppm), not present in conventional MOX fhel, on cladding material performance. Three previous repmts"3 identified several compatibility issues relating to the presence of gallium in MOX fuel and its possible reaction with fiel cladding. Gallium initially present in weapons-grade (WG) plutonium is largely removed during processing to produce MOX fhel. After blending the plutonium with uranium, only 1 to 10 ppm gallium is expected in the sintered MOX fuel. Gallium present as gallium oxide (G~OJ could be evolved as the suboxide (G~O). Migration of the evolved G~O and diffusion of gallium in the MOX matrix along thermal gradients could lead to locally higher concentrations of G~03. Thus, while an extremely low concentration of gallium in MOX fiel almost ensures a lack of significant interaction of gallium whh Zircaloy fhel cladding, there remains a small probability that corrosion effects will not be negligible. General corrosion in the form of surface alloying resulting from formation of intermetallic compounds between Zircaloy and gallium should be ma& limited and, therefore, superficial because of the expected low ratio of gallium to the surface area or volume of the Zircaloy cladding. Although the expected concentration of gallium is low and there is very limited volubility of gallium in zirconium, especially at temperatures below 700 "C,4 grain boundary penetration and liquid metal embrittlement (LME) are forms of localized corrosion that were also considered. One fuel system darnage mechanism, pellet clad interaction, has led to some failure of the Zircaloy cladding in light-water reactors (LWRS). This has been attributed to stresses in the cladding and one or more aggressive fission products. Stress corrosion cracking by iodines' 6 and LME by cadmium7>8 have been reported, and it is known that Zircaloy can be embrittled by some low-melting metals, (e.g., mercury).g LME is a form of environmentally induced embrittlement that can induce cracking or loss of ductility. LME requties wetting and a tensile stress, but it does not require corrosion penetration. Experimentally, it has been demonstrated that gallium can cause embrittlement of some alloys (e.g., aluminum) at low temperatures,'"' ] ] but experiments relative to LME of zirconium by gallium have been limited and inconclusive.*2 This report describes a series of tests designed to establish the effects of low levels of residual gallium in WG-MOX fhel on its compatibility with Zircaloy. In addition, to establish damage mechanisms it was important to understand types of cladding interactions and available stiety margins with respect to gallium concentration.

D.F. Wilson; E.T. Manneschmidt; J.F. King; J.P. Strizak; J.R. DiStefano

1998-09-01T23:59:59.000Z

73

Effect of oxidation on the Mechanical Properties of Liquid Gallium and Eutectic Gallium-Indium  

E-Print Network (OSTI)

Liquid metals exhibit remarkable mechanical properties, in particular large surface tension and low viscosity. However, these properties are greatly affected by oxidation when exposed to air. We measure the viscosity, surface tension, and contact angle of gallium (Ga) and a eutectic gallium-indium alloy (eGaIn) while controlling such oxidation by surrounding the metal with an acid bath of variable concentration. Rheometry measurements reveal a yield stress directly attributable to an oxide skin that obscures the intrinsic behavior of the liquid metals. We demonstrate how the intrinsic viscosity can be obtained with precision through a scaling technique that collapses low- and high-Reynolds number data. Measuring surface tension with a pendant drop method, we show that the oxide skin generates a surface stress that mimics surface tension and develop a simple model to relate this to the yield stress obtained from rheometry. We find that yield stress, surface tension, and contact angle all transition from solid-...

Xu, Qin; Guo, Qiti; Jaeger, Heinrich; Brown, Eric

2012-01-01T23:59:59.000Z

74

It's Elemental - Isotopes of the Element Gallium  

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

Zinc Zinc Previous Element (Zinc) The Periodic Table of Elements Next Element (Germanium) Germanium Isotopes of the Element Gallium [Click for Main Data] Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information. Naturally Occurring Isotopes Mass Number Natural Abundance Half-life 69 60.108% STABLE 71 39.892% STABLE Known Isotopes Mass Number Half-life Decay Mode Branching Percentage 56 No Data Available Proton Emission (suspected) No Data Available 57 No Data Available Proton Emission (suspected) No Data Available 58 No Data Available Proton Emission (suspected) No Data Available 59 No Data Available Proton Emission (suspected) No Data Available 60 70 milliseconds Electron Capture 98.40%

75

Process for forming pure silver ohmic contacts to N- and P-type gallium arsenide materials  

DOE Patents (OSTI)

Disclosed is an improved process for manufacturing gallium arsenide semiconductor devices having as its components a n-type gallium arsenide substrate layer and a p-type gallium arsenide diffused layer. The improved process comprises forming a pure silver ohmic contact to both the diffuse layer and the substrate layer wherein the n-type layer comprises a substantially low doping carrier concentration.

Hogan, S.J.

1983-03-13T23:59:59.000Z

76

Pure silver ohmic contacts to N- and P- type gallium arsenide materials  

DOE Patents (OSTI)

Disclosed is an improved process for manufacturing gallium arsenide semiconductor devices having as its components an n-type gallium arsenide substrate layer and a p-type gallium arsenide diffused layer. The improved process comprises forming a pure silver ohmic contact to both the diffused layer and the substrate layer, wherein the n-type layer comprises a substantially low doping carrier concentration.

Hogan, Stephen J. (Golden, CO)

1986-01-01T23:59:59.000Z

77

Novel Nitride-Modified Multielectron Conversion Electrode ...  

Novel Nitride-Modified Multielectron Conversion Electrode Materials for Lithium Ion Batteries Note: The technology described above is an early stage opportunity.

78

Silicon nitride having a high tensile strength  

Science Conference Proceedings (OSTI)

A ceramic body comprising at least about 80 w/o silicon nitride and having a mean tensile strength of at least about 800 MPa.

Pujari, Vimal K. (Northboro, MA); Tracey, Dennis M. (Medfield, MA); Foley, Michael R. (Oxford, MA); Paille, Norman I. (Oxford, MA); Pelletier, Paul J. (Sutton, MA); Sales, Lenny C. (Grafton, MA); Willkens, Craig A. (Worcester, MA); Yeckley, Russell L. (Latrobe, PA)

1998-01-01T23:59:59.000Z

79

Available Technologies: Synthesizing Boron Nitride Nanotubes and ...  

Nano- & Micro-technology; Software and IT ; Licensing Interest Form Receive Customized Tech Alerts. Synthesizing Boron Nitride Nanotubes and Related Nanoparticles

80

Effect of oxidation on the Mechanical Properties of Liquid Gallium and Eutectic Gallium-Indium  

E-Print Network (OSTI)

Liquid metals exhibit remarkable mechanical properties, in particular large surface tension and low viscosity. However, these properties are greatly affected by oxidation when exposed to air. We measure the viscosity, surface tension, and contact angle of gallium (Ga) and a eutectic gallium-indium alloy (eGaIn) while controlling such oxidation by surrounding the metal with an acid bath of variable concentration. Rheometry measurements reveal a yield stress directly attributable to an oxide skin that obscures the intrinsic behavior of the liquid metals. We demonstrate how the intrinsic viscosity can be obtained with precision through a scaling technique that collapses low- and high-Reynolds number data. Measuring surface tension with a pendant drop method, we show that the oxide skin generates a surface stress that mimics surface tension and develop a simple model to relate this to the yield stress obtained from rheometry. We find that yield stress, surface tension, and contact angle all transition from solid-like to liquid behavior at the same critical acid concentration, thereby quantitatively confirming that the wettability of these liquid metals is due to the oxide skin.

Qin Xu; Nikolai Qudalov; Qiti Guo; Heinrich Jaeger; Eric Brown

2012-01-23T23:59:59.000Z

Note: This page contains sample records for the topic "gallium nitride ingan" 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

Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers  

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

Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Low-dimensional materials have gained much attention not only because of the nonstop march toward miniaturization in the electronics industry but also for the exotic properties that are inherent in their small size. One approach for creating low-dimensional structures is to exploit the nanoscale or atomic-scale features that exist naturally in the three-dimensional (bulk) form of materials. By this means, a group from the University of Washington has demonstrated a new way of creating one-dimensional nanoscale structures (nanowires) in the compound gallium selenide. In short, ordered lines of structural vacancies in the material stimulate the growth of "one-dimensional" structures less than 1 nanometer in width.

82

Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers  

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

Vacancy-Induced Nanoscale Wire Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Wednesday, 21 December 2005 00:00 Low-dimensional materials have gained much attention not only because of the nonstop march toward miniaturization in the electronics industry but also for the exotic properties that are inherent in their small size. One approach for creating low-dimensional structures is to exploit the nanoscale or atomic-scale features that exist naturally in the three-dimensional (bulk) form of materials. By this means, a group from the University of Washington has demonstrated a new way of creating one-dimensional nanoscale structures (nanowires) in the compound gallium selenide. In short, ordered lines of structural vacancies in the material stimulate the growth of "one-dimensional" structures less than 1 nanometer in width.

83

Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers  

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

Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Low-dimensional materials have gained much attention not only because of the nonstop march toward miniaturization in the electronics industry but also for the exotic properties that are inherent in their small size. One approach for creating low-dimensional structures is to exploit the nanoscale or atomic-scale features that exist naturally in the three-dimensional (bulk) form of materials. By this means, a group from the University of Washington has demonstrated a new way of creating one-dimensional nanoscale structures (nanowires) in the compound gallium selenide. In short, ordered lines of structural vacancies in the material stimulate the growth of "one-dimensional" structures less than 1 nanometer in width.

84

Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers  

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

Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Low-dimensional materials have gained much attention not only because of the nonstop march toward miniaturization in the electronics industry but also for the exotic properties that are inherent in their small size. One approach for creating low-dimensional structures is to exploit the nanoscale or atomic-scale features that exist naturally in the three-dimensional (bulk) form of materials. By this means, a group from the University of Washington has demonstrated a new way of creating one-dimensional nanoscale structures (nanowires) in the compound gallium selenide. In short, ordered lines of structural vacancies in the material stimulate the growth of "one-dimensional" structures less than 1 nanometer in width.

85

Influences of excitation-dependent bandstructure changes on InGaN light-emitting diode efficiency  

E-Print Network (OSTI)

Bandstructure properties in wurtzite quantum wells can change appreciably with changing carrier density because of screening of quantum-confined Stark effect. An approach for incorporating these changes in an InGaN light-emitting-diode model is described. Bandstructure is computed for different carrier densities by solving Poisson and k\\cdotp equations in the envelop approximation. The information is used as input in a dynamical model for populations in momentum-resolved electron and hole states. Application of the approach is illustrated by modeling device internal quantum efficiency as a function of excitation.

Chow, Weng W

2011-01-01T23:59:59.000Z

86

Modeling of temperature and excitation dependences of efficiency in an InGaN light-emitting diode  

E-Print Network (OSTI)

The changes in excitation dependence of efficiency with temperature is modeled for a wurtzite InGaN light-emitting diode. The model incorporates bandstructure changes with carrier density arising from screening of quantum-confined Stark effect. Bandstructure is computed by solving Poisson and k.p equations in the envelop approximation. The information is used in a dynamical model for populations in momentum-resolved electron and hole states. Application of the approach shows the interplay of quantum-well and barrier emissions giving rise to shape changes in efficiency versus current density with changing temperature, as observed in some experiments.

Chow, Weng W

2013-01-01T23:59:59.000Z

87

Method for improving the growth of cadmium telluride on a gallium arsenide substrate  

DOE Patents (OSTI)

A method for preparing a gallium arsenide substrate, prior to growing a layer of cadmium telluride on a support surface thereof. The preparation includes the steps of cleaning the gallium arsenide substrate and thereafter forming prepatterned shapes on the support surface of the gallium arsenide substrate. The layer of cadmium telluride then grown on the prepared substrate results in dislocation densities of approximately 1{times}10{sup 6}/cm{sup 2} or less. The prepatterned shapes on the support surface of the gallium arsenide substrate are formed by reactive ion etching an original outer surface of the gallium arsenide substrate and into the body of the gallium arsenide substrate to a depth of at least two microns. The prepatterned shapes have the appearance of cylindrical mesas each having a diameter of at lease twelve microns. After the mesas are formed on the support surface of the gallium arsenide substrate, the substrate is again cleaned.

Reno, J.L.

1990-12-31T23:59:59.000Z

88

Method of preparation of uranium nitride  

SciTech Connect

Method for producing terminal uranium nitride complexes comprising providing a suitable starting material comprising uranium; oxidizing the starting material with a suitable oxidant to produce one or more uranium(IV)-azide complexes; and, sufficiently irradiating the uranium(IV)-azide complexes to produce the terminal uranium nitride complexes.

Kiplinger, Jaqueline Loetsch; Thomson, Robert Kenneth James

2013-07-09T23:59:59.000Z

89

Synthesis of transition metal nitride by nitridation of metastable oxide precursor  

SciTech Connect

Metastable transition metal oxides were used as precursors to synthesize transition metal nitrides at low temperature. Amorphous MoO{sub 2} was prepared by reduction of (NH{sub 4}){sub 6}Mo{sub 7}O{sub 24} solution with hydrazine. As-synthesized amorphous MoO{sub 2} was transformed into fcc {gamma}-Mo{sub 2}N at 400 Degree-Sign C and then into hexagonal {delta}-MoN by further increasing the temperature to 600 Degree-Sign C under a NH{sub 3} flow. The nitridation temperature employed here is much lower than that employed in nitridation of crystalline materials, and the amorphous materials underwent a unique nitridation process. Besides this, the bimetallic nitride Ni{sub 2}Mo{sub 3}N was also synthesized by nitridating amorphous bimetallic precursor. These results suggested that the nitridation of amorphous precursor possessed potential to be a general method for synthesizing many interstitial metallic compounds, such as nitrides and carbides at low temperature. - graphical abstract: Amorphous oxide was used as new precursor to prepare nitride at low temperature. Pure {gamma}-Mo{sub 2}N and {delta}-MoN were obtained at 400 Degree-Sign C and at 600 Degree-Sign C, respectively. Highlights: Black-Right-Pointing-Pointer We bring out a new method to synthesize transition metal nitrides at low temperature. Black-Right-Pointing-Pointer Both mono- and bimetallic molybdenum nitrides were synthesized at a mild condition. Black-Right-Pointing-Pointer The formation of two different molybdenum nitrides {gamma}-Mo{sub 2}N and {delta}-MoN can be controlled from the same metastable precursor. Black-Right-Pointing-Pointer The nitridation temperature was much lower than that reported from crystalline precursors. Black-Right-Pointing-Pointer The metastable precursor had different reaction process in comparison with crystalline precursor.

Wang, Huamin; Wu, Zijie; Kong, Jing [Key Laboratory of Advanced Energy Materials Chemistry (MOE), College of Chemistry, Nankai University, Tianjin 300071 (China)] [Key Laboratory of Advanced Energy Materials Chemistry (MOE), College of Chemistry, Nankai University, Tianjin 300071 (China); Wang, Zhiqiang, E-mail: zqwang@mail.nankai.edu.cn [Key Laboratory of Advanced Energy Materials Chemistry (MOE), College of Chemistry, Nankai University, Tianjin 300071 (China) [Key Laboratory of Advanced Energy Materials Chemistry (MOE), College of Chemistry, Nankai University, Tianjin 300071 (China); Tianjin Key Laboratory of Water Environment and Resources, Tianjin Normal University, No. 393 Binshui Road, Xiqing Dist., Tianjin 300387 (China); Zhang, Minghui, E-mail: zhangmh@nankai.edu.cn [Key Laboratory of Advanced Energy Materials Chemistry (MOE), College of Chemistry, Nankai University, Tianjin 300071 (China)] [Key Laboratory of Advanced Energy Materials Chemistry (MOE), College of Chemistry, Nankai University, Tianjin 300071 (China)

2012-10-15T23:59:59.000Z

90

nature materials | VOL 3 | SEPTEMBER 2004 | www.nature.com/naturematerials 601 ince 1993, InGaN light-emitting diodes (LEDs) have been  

E-Print Network (OSTI)

not fulfilled their original promise as solid-state replacements for light bulbs as their light, InGaN light-emitting diodes (LEDs) have been improved and commercialized1,2 , but these devices have and the spontaneous emissionrateinthesemiconductor3­9 ,andleadtotheenhancementof light emission by SP­QW coupling10

Okamoto, Koichi

91

Growths of staggered InGaN quantum wells light-emitting diodes emitting at 520525 nm employing graded growth-temperature profile  

E-Print Network (OSTI)

Growths of staggered InGaN quantum wells light-emitting diodes emitting at 520­525 nm employing current spreading and light extraction in GaN-based light emitting diodes Appl. Phys. Lett. 100, 061107 (2012) Electrically driven nanopyramid green light emitting diode Appl. Phys. Lett. 100, 061106 (2012

Gilchrist, James F.

92

Silicon nitride reinforced with molybdenum disilicide  

DOE Patents (OSTI)

Compositions of matter comprised of silicon nitride and molybdenum disilicide and methods of making the compositions, where the molybdenum disilicide is present in amounts ranging from about 5 to about 50 vol%.

Petrovic, J.J.; Honnell, R.E.

1990-12-31T23:59:59.000Z

93

Low temperature route to uranium nitride  

SciTech Connect

A method of preparing an actinide nitride fuel for nuclear reactors is provided. The method comprises the steps of a) providing at least one actinide oxide and optionally zirconium oxide; b) mixing the oxide with a source of hydrogen fluoride for a period of time and at a temperature sufficient to convert the oxide to a fluoride salt; c) heating the fluoride salt to remove water; d) heating the fluoride salt in a nitrogen atmosphere for a period of time and at a temperature sufficient to convert the fluorides to nitrides; and e) heating the nitrides under vacuum and/or inert atmosphere for a period of time sufficient to convert the nitrides to mononitrides.

Burrell, Anthony K. (Los Alamos, NM); Sattelberger, Alfred P. (Darien, IL); Yeamans, Charles (Berkeley, CA); Hartmann, Thomas (Idaho Falls, ID); Silva, G. W. Chinthaka (Las Vegas, NV); Cerefice, Gary (Henderson, NV); Czerwinski, Kenneth R. (Henderson, NV)

2009-09-01T23:59:59.000Z

94

Method of nitriding refractory metal articles  

DOE Patents (OSTI)

A method of nitriding a refractory-nitride forming metal or metalloid articles and composite articles. A consolidated metal or metalloid article or composite is placed inside a microwave oven and nitrogen containing gas is introduced into the microwave oven. The metal or metalloid article or composite is heated to a temperature sufficient to react the metal or metalloid with the nitrogen by applying a microwave energy within the microwave oven. The metal or metalloid article or composite is maintained at that temperature for a period of time sufficient to convert the article of metal or metalloid or composite to an article or composite of refractory nitride. In addition, a method of applying a coating, such as a coating of an oxide, a carbide, or a carbo-nitride, to an article of metal or metalloid by microwave heating.

Tiegs, Terry N. (Lenoir City, TN); Holcombe, Cressie E. (Knoxville, TN); Dykes, Norman L. (Oak Ridge, TN); Omatete, Ogbemi O. (Lagos, NG); Young, Albert C. (Flushing, NY)

1994-01-01T23:59:59.000Z

95

Method of nitriding refractory metal articles  

DOE Patents (OSTI)

A method of nitriding a refractory-nitride forming metal or metalloid articles and composite articles. A consolidated metal or metalloid article or composite is placed inside a microwave oven and nitrogen containing gas is introduced into the microwave oven. The metal or metalloid article or composite is heated to a temperature sufficient to react the metal or metalloid with the nitrogen by applying a microwave energy within the microwave oven. The metal or metalloid article or composite is maintained at that temperature for a period of time sufficient to convert the article of metal or metalloid or composite to an article or composite of refractory nitride. In addition, a method of applying a coating, such as a coating of an oxide, a carbide, or a carbo-nitride, to an article of metal or metalloid by microwave heating.

Tiegs, T.N.; Holcombe, C.E.; Dykes, N.L.; Omatete, O.O.; Young, A.C.

1994-03-15T23:59:59.000Z

96

Silicon nitride reinforced with molybdenum disilicide  

DOE Patents (OSTI)

Compositions of matter comprised of silicon nitride and molybdenum disilicide and methods of making the compositions, where the molybdenum disilicide is present in amounts ranging from about 5 to about 50 vol. %.

Petrovic, John J. (Los Alamos, NM); Honnell, Richard E. (Los Alamos, NM)

1991-01-01T23:59:59.000Z

97

Effects of asymmetry on electron spin dynamics in gallium arsenide quantum wells.  

E-Print Network (OSTI)

??This work presents optical studies of electron spin dynamics in gallium arsenide (GaAs) quantum wells, focusing on the effect of inversion asymmetric confinement potentials on… (more)

Eldridge, Peter Stephen

2009-01-01T23:59:59.000Z

98

Preparation Of Copper Indium Gallium Diselenide Films For Solar Cells  

DOE Patents (OSTI)

High quality thin films of copper-indium-gallium-diselenide useful in the production of solar cells are prepared by electrodepositing at least one of the constituent metals onto a glass/Mo substrate, followed by physical vapor deposition of copper and selenium or indium and selenium to adjust the final stoichiometry of the thin film to approximately Cu(In,Ga)Se.sub.2. Using an AC voltage of 1-100 KHz in combination with a DC voltage for electrodeposition improves the morphology and growth rate of the deposited thin film. An electrodeposition solution comprising at least in part an organic solvent may be used in conjunction with an increased cathodic potential to increase the gallium content of the electrodeposited thin film.

Bhattacharya, Raghu N. (Littleton, CO); Contreras, Miguel A. (Golden, CO); Keane, James (Lakewood, CO); Tennant, Andrew L. (Denver, CO), Tuttle, John R. (Denver, CO); Ramanathan, Kannan (Lakewood, CO); Noufi, Rommel (Golden, CO)

1998-08-08T23:59:59.000Z

99

Hybrid silicon nanocrystal silicon nitride dynamic random access memory  

Science Conference Proceedings (OSTI)

This paper introduces a silicon nanocrystal-silicon nitride hybrid single transistor cell for potential dynamic RAM (DRAM) applications that stores charge in silicon nanocrystals or a silicon nitride charge trapping layer or both. The memory operates ...

R. F. Steimle; M. Sadd; R. Muralidhar; Rajesh Rao; B. Hradsky; S. Straub; B. E. White, Jr.

2003-12-01T23:59:59.000Z

100

Appraisal of lupus nephritis by renal imaging with gallium-67  

Science Conference Proceedings (OSTI)

To assess the activity of lupus nephritis, 43 patients with systemic lupus erythematosus (SLE) were studied by gallium imaging. Delayed renal visualization 48 hours after the gallium injection, a positive result, was noted in 25 of 48 scans. Active renal disease was defined by the presence of hematuria, pyuria (10 or more red blood cells or white blood cells per high-power field), proteinuria (1 g or more per 24 hours), a rising serum creatinine level, or a recent biopsy specimen showing proliferative and/or necrotizing lesions involving more than 20 percent of glomeruli. Renal disease was active in 18 instances, inactive in 23, and undetermined in seven (a total of 48 scans). Sixteen of the 18 scans (89 percent) in patients with active renal disease showed positive findings, as compared with only four of 23 scans (17 percent) in patients with inactive renal disease (p less than 0.001). Patients with positive scanning results had a higher rate of hypertension (p = 0.02), nephrotic proteinuria (p = 0.01), and progressive renal failure (p = 0.02). Mild mesangial nephritis (World Health Organization classes I and II) was noted only in the patients with negative scanning results (p = 0.02) who, however, showed a higher incidence of severe extrarenal SLE (p = 0.04). It is concluded that gallium imaging is a useful tool in evaluating the activity of lupus nephritis.

Bakir, A.A.; Lopez-Majano, V.; Hryhorczuk, D.O.; Rhee, H.L.; Dunea, G.

1985-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "gallium nitride ingan" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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101

Silicon nitride ceramic having high fatigue life and high toughness  

DOE Patents (OSTI)

A sintered silicon nitride ceramic comprising between about 0.6 mol % and about 3.2 mol % rare earth as rare earth oxide, and between about 85 w/o and about 95 w/o beta silicon nitride grains, wherein at least about 20% of the beta silicon nitride grains have a thickness of greater than about 1 micron.

Yeckley, Russell L. (Oakham, MA)

1996-01-01T23:59:59.000Z

102

Using the genetic algorithm to design gallium indium nitride/gallium nitride light-emitting diodes with reduced efficiency droop and reduced spectral instability with respect to injection current  

Science Conference Proceedings (OSTI)

Today we are witnessing a fast growing trend that is redefining the concept of lighting. Numerous governments from all over the world have passed legislation to phase out incandescent light bulbs, with the objective of encouraging energy-efficient ...

Roya Mirhosseini / Partha S. Dutta

2010-01-01T23:59:59.000Z

103

Characteristics of graphene FET directly transformed from a resist pattern through interfacial graphitization of liquid gallium  

Science Conference Proceedings (OSTI)

We found that an extremely thin resist pattern on silicon dioxide can be directly transformed into a graphene field effect transistor (FET) channel via interfacial graphitization of liquid gallium. These patterned graphene FETs have p-type characteristics ... Keywords: Conductance, FET, Gallium, Graphene, Graphitization, Resist, Solid phase reaction

Jun-ichi Fujita; Ryuichi Ueki; Takuya Nishijima; Yosuke Miyazawa

2011-08-01T23:59:59.000Z

104

IEEE JOURNAL OF PHOTOVOLTAICS, VOL. 2, NO. 2, APRIL 2012 123 Gallium Arsenide Solar Cell Absorption  

E-Print Network (OSTI)

IEEE JOURNAL OF PHOTOVOLTAICS, VOL. 2, NO. 2, APRIL 2012 123 Gallium Arsenide Solar Cell Absorption flat gallium arsenide solar cell, we show that it is possible to modify the flow of light and enhance above the solar cell. The incoupling element is lossless and, thus, has the advantage that no energy

Grandidier, Jonathan

105

Measurement of achievable plutonium decontamination from gallium by means of PUREX solvent extraction  

SciTech Connect

The objective of the work described herein was to measure, experimentally, the achievable decontamination of plutonium from gallium by means of the PUREX solvent extraction process. Gallium is present in surplus weapons-grade plutonium (WG-Pu) at a concentration of approximately 1 wt%. Plans are to dispose of surplus WG-Pu by converting it to UO{sub 2}-PuO{sub 2} mixed oxide (MOX) fuel and irradiating it in commercial power reactors. However, the presence of high concentrations of gallium in plutonium is a potential corrosion problem during the process of MOX fuel irradiation. The batch experiments performed in this study were designed to measure the capability of the PUREX solvent extraction process to separate gallium from plutonium under idealized conditions. Radioactive tracing of the gallium with {sup 72}Ga enabled the accurate measurement of low concentrations of extractable gallium. The experiments approximated the proposed flowsheet for WG-Pu purification, except that only one stage was used for each process: extraction, scrubbing, and stripping. With realistic multistage countercurrent systems, much more efficient separations are generally obtained. The gallium decontamination factor (DF) obtained after one extraction stage was about 3 x 10{sup 6}. After one scrub stage, all gallium measurements were less than the detection limit, which corresponded to DFs >5 x 10{sup 6}. All these values exceed a 10{sup 6} DF needed to meet a hypothetical 10-ppb gallium impurity limit in MOX fuel. The results of this study showed no inherent or fundamental problem with regard to removing gallium from plutonium.

Collins, E.D.; Campbell, D.O.; Felker, L.K.

2000-01-01T23:59:59.000Z

106

DESIGN AND ANALYSIS OF AN INTEGRATED PULSE MODULATED S-BAND POWER AMPLIFIER IN GALLIUM NITRIDE PROCESS  

SciTech Connect

The design of power amplifiers in any semi-conductor process is not a trivia exercise and it is often encountered that the simulated solution is qualitatively different than the results obtained. Phenomena such as oscillation occurring either in-band or out of band and sometimes at subharmonic intervals, continuous spectrum noticed in some frequency bands, often referred to as chaos, and jumps and hysteresis effects can all be encountered and render a design useless. All of these problems might have been identified through a more rigorous approach to stability analysis. Designing for stability is probably the one area of amplifier design that receives the least amount of attention but incurs the most catastrophic of effects if it is not performed properly. Other parameters such as gain, power output, frequency response and even matching may suitable mitigation paths. But the lack of stability in an amplifier has no mitigating path. In addition to of loss of the design completely there are the increased production cycle costs, costs involved with investigating and resolving the problem and the costs involved with schedule slips or delays resulting from it. The Linville or Rollett stability criteria that many microwave engineers follow and rely exclusively on is not sufficient by itself to ensure a stable and robust design. It will be shown that the universal belief that unconditional stability is obtained through an analysis of the scattering matrix S to determine if 1 and |{Delta}{sub S}| < 1 is only part of the procedure and other tools must be used to validate the criteria. The research shown contributes to the state of the art by developing a more thorough stability design technique for designing amplifiers of any class, whether that be current mode or switch mode, than is currently undertaken with the goal of obtaining first pass design success.

STEVE SEDLOCK

2012-04-04T23:59:59.000Z

107

Comparative band alignment of plasma-enhanced atomic layer deposited high-k dielectrics on gallium nitride  

SciTech Connect

Al{sub 2}O{sub 3} films, HfO{sub 2} films, and HfO{sub 2}/Al{sub 2}O{sub 3} stacked structures were deposited on n-type, Ga-face, GaN wafers using plasma-enhanced atomic layer deposition (PEALD). The wafers were first treated with a wet-chemical clean to remove organics and an in-situ combined H{sub 2}/N{sub 2} plasma at 650 Degree-Sign C to remove residual carbon contamination, resulting in a clean, oxygen-terminated surface. This cleaning process produced slightly upward band bending of 0.1 eV. Additional 650 Degree-Sign C annealing after plasma cleaning increased the upward band bending by 0.2 eV. After the initial clean, high-k oxide films were deposited using oxygen PEALD at 140 Degree-Sign C. The valence band and conduction band offsets (VBOs and CBOs) of the Al{sub 2}O{sub 3}/GaN and HfO{sub 2}/GaN structures were deduced from in-situ x-ray and ultraviolet photoemission spectroscopy (XPS and UPS). The valence band offsets were determined to be 1.8 and 1.4 eV, while the deduced conduction band offsets were 1.3 and 1.0 eV, respectively. These values are compared with the theoretical calculations based on the electron affinity model and charge neutrality level model. Moreover, subsequent annealing had little effect on these offsets; however, the GaN band bending did change depending on the annealing and processing. An Al{sub 2}O{sub 3} layer was investigated as an interfacial passivation layer (IPL), which, as results suggest, may lead to improved stability, performance, and reliability of HfO{sub 2}/IPL/GaN structures. The VBOs were {approx}0.1 and 1.3 eV, while the deduced CBOs were 0.6 and 1.1 eV for HfO{sub 2} with respect to Al{sub 2}O{sub 3} and GaN, respectively.

Yang Jialing; Eller, Brianna S.; Zhu Chiyu; England, Chris; Nemanich, Robert J. [Department of Physics, Arizona State University, Tempe, Arizona 85287-1504 (United States)

2012-09-01T23:59:59.000Z

108

High-Efficiency Nitride-Based Solid-State Lighting  

SciTech Connect

In this final technical progress report we summarize research accomplished during Department of Energy contract DE-FC26-01NT41203, entitled ''High-Efficiency Nitride-Based Solid-State Lighting''. Two teams, from the University of California at Santa Barbara (Principle Investigator: Dr. Shuji Nakamura) and the Lighting Research Center at Rensselaer Polytechnic Institute (led by Dr. N. Narendran), pursued the goals of this contract from thin film growth, characterization, and packaging/luminaire design standpoints. The UCSB team initially pursued the development of blue gallium nitride (GaN)-based vertical-cavity surface-emitting lasers, as well as ultraviolet GaN-based light emitting diodes (LEDs). In Year 2, the emphasis shifted to resonant-cavity light emitting diodes, also known as micro-cavity LEDs when extremely thin device cavities are fabricated. These devices have very directional emission and higher light extraction efficiency than conventional LEDs. Via the optimization of thin-film growth and refinement of device processing, we decreased the total cavity thickness to less than 1 {micro}m, such that micro-cavity effects were clearly observed and a light extraction efficiency of over 10% was reached. We also began the development of photonic crystals for increased light extraction, in particular for so-called ''guided modes'' which would otherwise propagate laterally in the device and be re-absorbed. Finally, we pursued the growth of smooth, high-quality nonpolar a-plane and m-plane GaN films, as well as blue light emitting diodes on these novel films. Initial nonpolar LEDs showed the expected behavior of negligible peak wavelength shift with increasing drive current. M-plane LEDs in particular show promise, as unpackaged devices had unsaturated optical output power of {approx} 3 mW at 200 mA drive current. The LRC's tasks were aimed at developing the subcomponents necessary for packaging UCSB's light emitting diodes, and packaging them to produce a white light fixture. During the third and final year of the project, the LRC team investigated alternate packaging methods for the white LED device to achieve at least 25 percent more luminous efficacy than traditional white LEDs; conducted optical ray-tracing analyses and human factors studies to determine the best form factor for the white light source under development, in terms of high luminous efficacy and greater acceptance by subjects; and developed a new die encapsulant using silicone-epoxy resins that showed less yellowing and slower degradation. At the conclusion of this project, the LRC demonstrated a new packaging method, called scattered photon extraction (SPE), that produced an average luminous flux and corresponding average efficacy of 90.7 lm and 36.3 lm/W, respectively, compared with 56.5 lm and 22.6 lm/W for a similar commercial white LED package. At low currents, the SPE package emitted white light with an efficacy of over 80 lm/W and had chromaticity values very close to the blackbody locus. The SPE package showed an overall improvement of 61% for this particular comparison, exceeding the LRC's third-year goal of 25% improvement.

Paul T. Fini; Shuji Nakamura

2005-07-30T23:59:59.000Z

109

Anisotropic Hexagonal Boron Nitride Nanomaterials - Synthesis and Applications  

SciTech Connect

Boron nitride (BN) is a synthetic binary compound located between III and V group elements in the Periodic Table. However, its properties, in terms of polymorphism and mechanical characteristics, are rather close to those of carbon compared with other III-V compounds, such as gallium nitride. BN crystallizes into a layered or a tetrahedrally linked structure, like those of graphite and diamond, respectively, depending on the conditions of its preparation, especially the pressure applied. Such correspondence between BN and carbon readily can be understood from their isoelectronic structures [1, 2]. On the other hand, in contrast to graphite, layered BN is transparent and is an insulator. This material has attracted great interest because, similar to carbon, it exists in various polymorphic forms exhibiting very different properties; however, these forms do not correspond strictly to those of carbon. Crystallographically, BN is classified into four polymorphic forms: Hexagonal BN (h-BN) (Figure 1(b)); rhombohedral BN (r-BN); cubic BN (c-BN); and wurtzite BN (w-BN). BN does not occur in nature. In 1842, Balmain [3] obtained BN as a reaction product between molten boric oxide and potassium cyanide under atmospheric pressure. Thereafter, many methods for its synthesis were reported. h-BN and r-BN are formed under ambient pressure. c-BN is synthesized from h-BN under high pressure at high temperature while w-BN is prepared from h-BN under high pressure at room temperature [1]. Each BN layer consists of stacks of hexagonal plate-like units of boron and nitrogen atoms linked by SP{sup 2} hybridized orbits and held together mainly by Van der Waals force (Fig 1(b)). The hexagonal polymorph has two-layered repeating units: AA'AA'... that differ from those in graphite: ABAB... (Figure 1(a)). Within the layers of h-BN there is coincidence between the same phases of the hexagons, although the boron atoms and nitrogen atoms are alternatively located along the c-axis. The rhombohedral system consists of three-layered units: ABCABC..., whose honeycomb layers are arranged in a shifted phase, like as those of graphite. Reflecting its weak interlayer bond, the h-BN can be cleaved easily along its layers, and hence, is widely used as a lubricant material. The material is stable up to a high temperature of 2300 C before decomposition sets in [2] does not fuse a nitrogen atmosphere of 1 atm, and thus, is applicable as a refractory material. Besides having such properties, similar to those of graphite, the material is transparent, and acts as a good electric insulator, especially at high temperatures (10{sup 6} {Omega}m at 1000 C) [1]. c-BN and w-BN are tetrahedrally linked BN. The former has a cubic sphalerite-type structure, and the latter has a hexagonal wurtzite-type structure. c-BN is the second hardest known material (the hardest is diamond), the so-called white diamond. It is used mainly for grinding and cutting industrial ferrous materials because it does not react with molten iron, nickel, and related alloys at high temperatures whereas diamond does [1]. It displays the second highest thermal conductivity (6-9 W/cm.deg) after diamond. This chapter focuses principally upon information about h-BN nanomaterials, mainly BN nanotubes (BNNTs), porous BN, mono- and few-layer-BN sheets. There are good reviews book chapters about c-BN in [1, 4-6].

Han,W.Q.

2008-08-01T23:59:59.000Z

110

Silicon-nitride and metal composite  

SciTech Connect

A composite and a method for bonding the composite. The composite includes a ceramic portion of silicon nitride, a refractory metal portion and a layer of MoSi.sub.2 indirectly bonding the composite together. The method includes contacting the layer of MoSi.sub.2 with a surface of the silicon nitride and with a surface of the metal; heating the layer to a temperature below 1400.degree. C.; and, simultaneously with the heating, compressing the layer such that the contacting is with a pressure of at least 30 MPa. This composite overcomes useful life problems in the fabrication of parts for a helical expander for use in power generation.

Landingham, Richard L. (Livermore, CA); Huffsmith, Sarah A. (Urbana, IL)

1981-01-01T23:59:59.000Z

111

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

112

Titanium nitride electrodes for thermoelectric generators  

DOE Patents (OSTI)

The invention is directed to a composite article suitable for use in thermoelectric generators. The article comprises a thin film of titanium nitride as an electrode deposited onto solid electrolyte. The invention is also directed to the method of making same.

Novak, Robert F. (Farmington Hills, MI); Schmatz, Duane J. (Dearborn Heights, MI); Hunt, Thomas K. (Ann Arbor, MI)

1987-12-22T23:59:59.000Z

113

Silicon nitride having a high tensile strength  

DOE Patents (OSTI)

A silicon nitride ceramic comprising: a) inclusions no greater than 25 microns in length, b) agglomerates no greater than 20 microns in diameter, and c) a surface finish of less than about 8 microinches, said ceramic having a four-point flexural strength of at least about 900 MPa.

Pujari, Vimal K. (Northboro, MA); Tracey, Dennis M. (Medfield, MA); Foley, Michael R. (Oxford, MA); Paille, Norman I. (Oxford, MA); Pelletier, Paul J. (Millbury, MA); Sales, Lenny C. (Grafton, MA); Willkens, Craig A. (Sterling, MA); Yeckley, Russell L. (Oakham, MA)

1996-01-01T23:59:59.000Z

114

Gallium phosphide high-temperature bipolar junction transistor  

DOE Green Energy (OSTI)

Preliminary results are reported on the development of a high-temperature (> 350/sup 0/C) gallium phosphide bipolar junction transistor (BJT) for goethermal and other energy applications. This four-layer p/sup +/n/sup -/pp/sup +/ structure was fromed by liquid phase epitaxy using a supercooling technique to insure uniform nucleation of the thin layers. Magnesium was used as the p-type dopant to avoid excessive out-diffusion into the lightly doped base. By appropriate choice of electrodes, the device may also be driven as an n-channel junction field-effect transistor. The gallium phosphide BJT is observed to have a common-emitter current gain peaking in the range of 6 to 10 (for temperatures from 20/sup 0/C to 400/sup 0/C) and a room-temperature, punchthrough-limited, collector-emitter breakdown voltage of approximately -6V. Other parameters of interest include an f/sub/ = 400 KHz (at 20/sup 0/C) and a collector base leakage current = 200 ..mu..A (at 350/sup 0/C).

Zipperian, T.E.; Dawson, L.R.; Caffin, R.J.

1981-03-01T23:59:59.000Z

115

Microsoft PowerPoint - Gallium Oxide_Ramana  

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

Gallium Oxide Nanostructures Gallium Oxide Nanostructures for High Temperature Sensors C.V. Ramana (PI) Evgeny Shafirovich (Co-PI) Mechanical Engineering, University of Texas at El Paso Students: Ernesto Rubio (PhD); S.K. Samala (MS) A.K. Narayana Swamy (PhD); K. Abhilash (MS) Program Manager: Richard Dunst, NETL, DOE Project: DE-FE0007225 Project Period: 10/01/2011 to 09/31/2014 1 06/12/2013 DOE UCR/HBCU Conference, June 11-13, 2013 2 ď‚· Introduction ď‚· Research Objectives ď‚· Experiments â–ş Synthesis â–ş Characterization ď‚· Results and Discussion â–ş Pure Ga 2 O 3 Thin Films â–ş W-doped Ga 2 O 3 Thin Films (Physical Methods) ď‚· Summary & Future Work 06/12/2013 DOE UCR/HBCU Conference, June 11-13, 2013 3 06/12/2013 DOE UCR/HBCU Conference, June 11-13, 2013 4 Energy Systems High-T High-T High-P High-P

116

Limits on nu_e and anti-nu_e disappearance from Gallium and reactor experiments  

E-Print Network (OSTI)

The deficit observed in the Gallium radioactive source experiments is interpreted as a possible indication of the disappearance of electron neutrinos. In the effective framework of two-neutrino mixing we obtain $\\sin^{2}2\\vartheta \\gtrsim 0.03$ and $\\Delta{m}^{2} \\gtrsim 0.1 \\text{eV}^{2}$. The compatibility of this result with the data of the Bugey and Chooz reactor short-baseline antineutrino disappearance experiments is studied. It is found that the Bugey data present a hint of neutrino oscillations with $0.02 \\lesssim \\sin^{2}2\\vartheta \\lesssim 0.08$ and $\\Delta{m}^{2} \\approx 1.8 \\text{eV}^{2}$, which is compatible with the Gallium allowed region of the mixing parameters. This hint persists in the combined analyses of Bugey and Chooz data, of Gallium and Bugey data, and of Gallium, Bugey, and Chooz data.

Mario A. Acero; Carlo Giunti; Marco Laveder

2007-11-27T23:59:59.000Z

117

Polycrystalline Thin-Film Research: Copper Indium Gallium Diselenide (Fact Sheet)  

DOE Green Energy (OSTI)

Capabilities fact sheet for the National Center for Photovoltaics: Polycrystalline Thin-Film Research: Copper Indium Gallium Diselenide that includes scope, core competencies and capabilities, and contact/web information.

Not Available

2011-06-01T23:59:59.000Z

118

The radiation bio-effects of gallum-72 on leukemic cells via a gallium-transferrin complex  

E-Print Network (OSTI)

Improved methods for treatment of leukemia would be advantageous for patients and the medical community. This thesis reports results of a study of the cytotoxicity of radiolabeled transferrin in cultured leukemic cells. K-562 cells, from an erythroleukemic cell line, were grown and growth curves were plotted for characterization. K-562 cells grew logarithmically from approximately 250,000 cells mL?ą to 700,000 cells mL?ą and display a doubling time of approximately 20-21 hours. K-562 cells were exposed to x rays at an absorbed dose of 0, 1, 2, and 4 gray. Growth curves were plotted to create a dose response curve. Percent-cell survival in this experiment, and all subsequent experiments, was determined based on the extrapolation of the growth curves to time zero, as compared to a control. An absorbed dose of 1, 2, and 4 gray corresponded to a survival of 77([]14)%, 45([]7.4)% and 20([]2.4)%, respectively. This cell line is relatively resistant to radiation. K-562 cells were exposed to a radioactive gallium-72/stable gallium nitrate mixture to determine the effect gallium-72 decay has on cell survival . Simultaneously, K-562 cells were exposed to a concentration of stable gallium nitrate equivalent to the total gallium concentration, radioactive and stable, of the gallium-72/stable gallium mixture. This allowed a comparison of radioactive and chemotoxic effects due to gallium-72 and stable gallium, respectively. Exposures to gallium-72, at an activity of 184.0 kBq mL?ą, and stable gallium nitrate, at a concentration of 116.7 []M, resulted in a cell survival of 61([]10.5)% and 75([]12. 1)%, respectively. The difference is small when error is taken into consideration. Therefore radioactivity had little effect on cell survival at a specific activity of 6.3 MBq mg?ą. To properly assess the cytotoxicity of gallium-72 the specific activity must be increased. To determine the effect of ape-transferrin on the cytotoxicity of gallium nitrate, K-562 cells were exposed to stable gallium nitrate and increasing amounts of apo-transferrin. Cells exposed to 115.0 []M gallium nitrate exhibited an 82([]8.8)% cell survival compared to 54([]6.9)% following exposure to 115.0 []M gallium nitrate and 3.75 []M apo-transferrin. Apo-transferrin presumably increases cellular uptake of gallium nitrate thereby increasing its cyctotoxic effects.

Forbes, Christen Douglas

1999-01-01T23:59:59.000Z

119

Available Technologies: Boron Nitride Nanotubes with Modified Surfaces  

Nano- & Micro-technology; Software and IT ; Licensing Interest Form Receive Customized Tech Alerts. Boron Nitride Nanotubes with Modified Surfaces . IB-2331 and IB-2332 .

120

Method for locating metallic nitride inclusions in metallic alloy ingots  

DOE Patents (OSTI)

A method of determining the location and history of metallic nitride and/or oxynitride inclusions in metallic melts. The method includes the steps of labeling metallic nitride and/or oxynitride inclusions by making a coreduced metallic-hafnium sponge from a mixture of hafnium chloride and the chloride of a metal, reducing the mixed chlorides with magnesium, nitriding the hafnium-labeled metallic-hafnium sponge, and seeding the sponge to be melted with hafnium-labeled nitride inclusions. The ingots are neutron activated and the hafnium is located by radiometric means. Hafnium possesses exactly the proper metallurgical and radiochemical properties for this use.

White, Jack C. (Albany, OR); Traut, Davis E. (Corvallis, OR); Oden, Laurance L. (Albany, OR); Schmitt, Roman A. (Corvallis, OR)

1992-01-01T23:59:59.000Z

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121

Processing of Optically Translucent/Transparent Nitrides from ...  

Science Conference Proceedings (OSTI)

With the aim coupling good thermal conductivity with optical light transmission and emission, aluminum nitride with rare earth dopants (Gd2O3, Gd ,Dy etc.) ...

122

Study of liquid gallium at high pressure using synchrotron x-ray  

SciTech Connect

Liquid gallium has been studied at high pressure up to 2 GPa and ambient temperature in a diamond anvil cell using high energy synchrotron x-ray beam. The total x-ray scattering data of liquid gallium were collected up to Q = 12 A{sup -1} and analyzed using pair distribution functions (PDF). The results indicate that the first nearest neighbor peak and second nearest neighbor (shoulder) peak of PDF in liquid gallium does not change with pressure, whereas the higher order (i.e., third and fourth) nearest neighbor peaks shift towards shorter distance with increasing pressure. Reverse Monte Carlo modeling based on the observed data shows that the coordination number in the liquid gallium increases with pressure from 10.5 at 0.3 GPa to 11.6 at 2 GPa. An atomic arrangement similar to the crystalline phase of Ga(II) with coordination number of 12 is proposed for the locally dense-packed rigid unit in liquid gallium. The volume compression data derived from the structure modeling yield a bulk modulus of 12.1(6) GPa for liquid gallium.

Yu, Tony; Guo Quanzhong; Parise, John [Department of Geosciences, Mineral Physics Institute, Stony Brook University, Stony Brook, New York 11794-2100 (United States); Chen Jiuhua [Department of Geosciences, Mineral Physics Institute, Stony Brook University, Stony Brook, New York 11794-2100 (United States); Department of Mechanical and Materials Engineering, Center for the Study of Matters at Extreme Conditions, Florida International University, Miami, Florida 33199 (United States); Ehm, Lars [Department of Geosciences, Mineral Physics Institute, Stony Brook University, Stony Brook, New York 11794-2100 (United States); National Synchrotron Light Source, Brookhaven National Laboratory, Upton, New York 11973-5000 (United States); Huang Shu [Department of Mechanical and Materials Engineering, Center for the Study of Matters at Extreme Conditions, Florida International University, Miami, Florida 33199 (United States); Luo Shengnian [Physics Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2012-06-01T23:59:59.000Z

123

High-Temperature Decomposition of Brřnsted Acid Sites in Gallium-Substituted Zeolites  

SciTech Connect

The dehydroxylation of Broensted acid sites (BAS) in Ga-substituted zeolites was investigated at temperatures up to 850 C using X-ray absorption spectroscopy (XAS), Fourier transform infrared spectroscopy (FTIR), and mass spectrometry-temperature programmed desorption (MS-TPD). X-ray absorption near-edge spectroscopy (XANES) revealed that the majority of gallium has tetrahedral coordination even after complete dehydroxylation. The interatomic gallium-oxygen distance and gallium coordination number determined by extended X-ray absorption fine structure (EXAFS) are consistent with gallium in tetrahedral coordination at low T (< 550 C). Upon heating Ga-Beta and Ga-ZSM5 to 850 C, analysis of the EXAFS showed that 70 and 80% of the gallium was still in tetrahedral coordination. The remainder of the gallium was found to be in octahedral coordination. No trigonal Ga atoms were observed. FTIR measurements carried out at similar temperatures show that the intensity of the OH vibration due to BAS has been eliminated. MS-TPD revealed that hydrogen in addition to water evolved from the samples during dehydroxylation. This shows that dehydrogenation in addition to dehydration is a mechanism that contributes to BAS decomposition. Dehydrogenation was further confirmed by exposing the sample to hydrogen to regenerate some of the BAS as monitored by FTIR and MS-TPD.

K Al-majnouni; N Hould; W Lonergan; D Vlachos; R Lobo

2011-12-31T23:59:59.000Z

124

Single event upsets in gallium arsenide dynamic logic  

SciTech Connect

The advantages and disadvantages of using gallium arsenide (GaAs) dynamic logic in computers and digital systems are briefly discussed, especially with respect to space applications. A short introduction to the topology and operation of GaAs Two-Phase Dynamic FET Logic (TDFL) circuits is presented. Experiments for testing the SEU sensitivity of GaAs TDFL, using a laser to create charge collection events, are described. Results are used to estimate the heavy-ion, soft error rate for TDFL in a spacecraft in geosynchronous orbit, and the dependence of the SEU sensitivity on clock frequency, clock voltage, and clock phase. Analysis of the data includes a comparison between the SEU sensitivities of TDFL and the more common static form of GaAs logic, Directly Coupled FET Logic (DCFL). This is the first reported SEU testing of GaAs dynamic logic.

Fouts, D.J. (Naval Postgraduate School, Monterey, CA (United States). ECE Dept.); Weatherford, T. (SFA Inc., Landover, MD (United States)); McMorrow, C.; Melinger, J.S.; Campbell, A.B. (Naval Research Lab., Washington, DC (United States))

1994-12-01T23:59:59.000Z

125

Coated gallium arsenide neutron detectors : results of characterizationmeasurements.  

DOE Green Energy (OSTI)

Effective detection of special nuclear materials (SNM) is essential for reducing the threat associated with stolen or improvised nuclear devices. Passive radiation detection technologies are primarily based on gamma-ray detection and subsequent isotope identification or neutron detection (specific to neutron sources and SNM). One major effort supported by the Department of Homeland Security in the area of advanced passive detection is handheld or portable neutron detectors for search and localization tasks in emergency response and interdiction settings. A successful SNM search detector will not only be able to confirm the presence of fissionable materials but also establish the location of the source in as short of time as possible while trying to minimize false alarms due to varying background or naturally occurring radioactive materials (NORM). For instruments based on neutron detectors, this translates to detecting neutrons from spontaneous fission or alpha-n reactions and being able to determine the direction of the source (or localizing the source through subsequent measurements). Polyethylene-coated gallium arsenide detectors were studied because the detection scheme is based on measuring the signal in the gallium arsenide wafers from the electrical charge of the recoil protons produced from the scattering of neutrons from the hydrogen nucleus. The inherent reaction has a directional dependence because the neutron and hydrogen nucleus have equivalent masses. The assessment and measurement of polyethylene-coated gallium arsenide detector properties and characteristics was the first phase of a project being performed for the Department of Homeland Security and the results of these tests are reported in this report. The ultimate goal of the project was to develop a man-portable neutron detection system that has the ability to determine the direction of the source from the detector. The efficiency of GaAs detectors for different sizes of polyethylene layers and different angles between the detector and the neutron source were determined. Preliminary measurements with a neutron generator based on a deuterium-tritium reaction ({approx}14 MeV neutrons) were performed and the results are discussed. This report presents the results of these measurements in terms of efficiency and angular efficiency and compares them to Monte Carlo calculations to validate the calculation scheme in view of further applications. Based on the results of this study, the polyethylene-coated gallium arsenide detectors provide adequate angular resolution based on proton recoil detection from the neutron scattering reaction from hydrogen. However, the intrinsic efficiency for an individual detector is extremely low. Because of this low efficiency, large surface area detectors ( or a large total surface area from many small detectors) would be required to generate adequate statistics to perform directional detection in near-real time. Large surface areas could be created by stacking the detector wafers with only a negligible attenuation of source neutrons. However, the cost of creating such a large array of GaAs is cost-prohibitive at this time.

Klann, R. T.; Perret, G.; Sanders, J.

2006-09-29T23:59:59.000Z

126

Indium and impurity incorporation in InGaN films on polar, nonpolar, and semipolar GaN orientations grown by ammonia molecular beam epitaxy  

SciTech Connect

The effects of NH{sub 3} flow, group III flux, and substrate growth temperature on indium incorporation and surface morphology have been investigated for bulk InGaN films grown by ammonia molecular beam epitaxy. The incorporation of unintentional impurity elements (H, C, O) in InGaN films was studied as a function of growth temperature for growth on polar (0001) GaN on sapphire templates, nonpolar (1010) bulk GaN, and semipolar (1122), (2021) bulk GaN substrates. Enhanced indium incorporation was observed on both (1010) and (2021) surfaces relative to c-plane, while reduced indium incorporation was observed on (1122) for co-loaded conditions. Indium incorporation was observed to increase with decreasing growth temperature for all planes, while being relatively unaffected by the group III flux rates for a 1:1 Ga:In ratio. Indium incorporation was found to increase at the expense of a decreased growth rate for higher ammonia flows; however, smooth surface morphology was consistently observed for growth on semipolar orientations. Increased concentrations of oxygen and hydrogen were observed on semipolar and nonpolar orientations with a clear trend of increased hydrogen incorporation with indium content.

Browne, David A.; Young, Erin C.; Lang, Jordan R.; Hurni, Christophe A.; Speck, James S. [Materials Department, University of California Santa Barbara, Santa Barbara, California 93106 (United States)

2012-07-15T23:59:59.000Z

127

Nitriding of super alloys for enhancing physical properties  

DOE Patents (OSTI)

The invention teaches the improvement of certain super alloys by exposing the alloy to an atmosphere of elemental nitrogen at elevated temperatures in excess of 750/sup 0/C but less than 1150/sup 0/C for an extended duration, viz., by nitriding the surface of the alloy, to establish barrier nitrides of the order of 25 to 100 micrometers thickness. These barrier

Purohit, A.

1984-06-25T23:59:59.000Z

128

III-Nitride LEDs with photonic crystal structures.  

SciTech Connect

Electrical operation of III-Nitride light emitting diodes (LEDs) with photonic crystal structures is demonstrated. Employing photonic crystal structures in III-Nitride LEDs is a method to increase light extraction efficiency and directionality. The photonic crystal is a triangular lattice formed by dry etching into the III-Nitride LED. A range of lattice constants is considered (a {approx} 270-340nm). The III-Nitride LED layers include a tunnel junction providing good lateral current spreading without a semi-absorbing metal current spreader as is typically done in conventional III-Nitride LEDs. These photonic crystal III-Nitride LED structures are unique because they allow for carrier recombination and light generation proximal to the photonic crystal (light extraction area) yet displaced from the absorbing metal contact. The photonic crystal Bragg scatters what would have otherwise been guided modes out of the LED, increasing the extraction efficiency. The far-field light radiation patterns are heavily modified compared to the typical III-Nitride LED's Lambertian output. The photonic crystal affects the light propagation out of the LED surface, and the radiation pattern changes with lattice size. LEDs with photonic crystals are compared to similar III-Nitride LEDs without the photonic crystal in terms of extraction, directionality, and emission spectra.

Wendt, Joel Robert; Sigalas, M. M. (Agilent Technologies, Palo Alto, CA); Epler, J. E. (Lumileds Lighting, San Jose, CA); Krames, M. R. (Lumileds Lighting, San Jose, CA); Li, D. (University of New Mexico, Albuquerque NM); Brueck, Stephen R. J. (University of New Mexico, Albuquerque NM); Shagam, M. (Boston University, Boston, MA); Gardner, N. F. (Lumileds Lighting, San Jose, CA); Wierer, Jonathan J. (Lumileds Lighting, San Jose, CA)

2005-02-01T23:59:59.000Z

129

Molybdenum enhanced low-temperature deposition of crystalline silicon nitride  

DOE Patents (OSTI)

A process for chemical vapor deposition of crystalline silicon nitride which comprises the steps of: introducing a mixture of a silicon source, a molybdenum source, a nitrogen source, and a hydrogen source into a vessel containing a suitable substrate; and thermally decomposing the mixture to deposit onto the substrate a coating comprising crystalline silicon nitride containing a dispersion of molybdenum silicide.

Lowden, Richard A. (Powell, TN)

1994-01-01T23:59:59.000Z

130

Oxidation Protection of Uranium Nitride Fuel using Liquid Phase Sintering  

SciTech Connect

Two methods are proposed to increase the oxidation resistance of uranium nitride (UN) nuclear fuel. These paths are: (1) Addition of USi{sub x} (e.g. U3Si2) to UN nitride powder, followed by liquid phase sintering, and (2) 'alloying' UN nitride with various compounds (followed by densification via Spark Plasma Sintering or Liquid Phase Sintering) that will greatly increase oxidation resistance. The advantages (high thermal conductivity, very high melting point, and high density) of nitride fuel have long been recognized. The sodium cooled BR-10 reactor in Russia operated for 18 years on uranium nitride fuel (UN was used as the driver fuel for two core loads). However, the potential advantages (large power up-grade, increased cycle lengths, possible high burn-ups) as a Light Water Reactor (LWR) fuel are offset by uranium nitride's extremely low oxidation resistance (UN powders oxidize in air and UN pellets decompose in hot water). Innovative research is proposed to solve this problem and thereby provide an accident tolerant LWR fuel that would resist water leaks and high temperature steam oxidation/spalling during an accident. It is proposed that we investigate two methods to increase the oxidation resistance of UN: (1) Addition of USi{sub x} (e.g. U{sub 3}Si{sub 2}) to UN nitride powder, followed by liquid phase sintering, and (2) 'alloying' UN nitride with compounds (followed by densification via Spark Plasma Sintering) that will greatly increase oxidation resistance.

Dr. Paul A. Lessing

2012-03-01T23:59:59.000Z

131

Process for producing ceramic nitrides anc carbonitrides and their precursors  

DOE Patents (OSTI)

A process for preparing ceramic nitrides and carbon nitrides in the form of very pure, fine particulate powder. Appropriate precursors is prepared by reaching a transition metal alkylamide with ammonia to produce a mixture of metal amide and metal imide in the form of an easily pyrolyzable precipitate.

Brown, G.M.; Maya, L.

1987-02-25T23:59:59.000Z

132

Hard and low friction nitride coatings and methods for forming the same  

DOE Patents (OSTI)

An improved coating material possessing super-hard and low friction properties and a method for forming the same. The improved coating material includes the use of a noble metal or soft metal homogeneously distributed within a hard nitride material. The addition of small amounts of such metals into nitrides such as molybdenum nitride, titanium nitride, and chromium nitride results in as much as increasing of the hardness of the material as well as decreasing the friction coefficient and increasing the oxidation resistance.

Erdemir, Ali (Naperville, IL); Urgen, Mustafa (Istanbul, TR); Cakir, Ali Fuat (Istanbul, TR); Eryilmaz, Osman Levent (Bolingbrook, IL); Kazmanli, Kursat (Istanbul, TR); Keles, Ozgul (Istanbul, TR)

2007-05-01T23:59:59.000Z

133

Titanium nitride thin films for minimizing multipactoring  

DOE Patents (OSTI)

Applying a thin film coating to the surface of a workpiece, in particular, applying a coating of titanium nitride to a klystron window by means of a crossed-field diode sputtering array. The array is comprised of a cohesive group of numerous small hollow electrically conducting cylinders and is mounted so that the open ends of the cylinders on one side of the group are adjacent a titanium cathode plate. The workpiece is mounted so as to face the open ends of the other side of the group. A magnetic field is applied to the array so as to be coaxial with the cylinders and a potential is applied across the cylinders and the cathode plate, the cylinders as an anode being positive with respect to the cathode plate. The cylinders, the cathode plate and the workpiece are situated in an atmosphere of nitrogen which becomes ionized such as by field emission because of the electric field between the cylinders and cathode plate, thereby establishing an anode-cathode discharge that results in sputtering of the titanium plate. The sputtered titanium coats the workpiece and chemically combines with the nitrogen to form a titanium nitride coating on the workpiece. Gas pressure, gas mixtures, cathode material composition, voltages applied to the cathode and anode, the magnetic field, cathode, anode and workpiece spacing, and the aspect ratio (ratio of length to inner diameter) of the anode cylinders, all may be controlled to provide consistent optimum thin film coatings of various compositions and thicknesses. Another facet of the disclosure is the coating of microwave components per se with titanium nitride to reduce multipactoring under operating conditions of the components.

Welch, Kimo M. (Mountain View, CA)

1979-01-01T23:59:59.000Z

134

Development of White-Light Emitting Active Layers in Nitride Based Heterostructures for Phosphorless Solid State Lighting  

SciTech Connect

This report provides a summary of research activities carried out at the University of California, San Diego and Central Research of OSRAM SYLVANIA in Beverly, MA partially supported by a research contract from US Department of Energy, DE-FC26-04NT422274. The main objective of this project was to develop III-V nitrides activated by rare earth ions, RE{sup 3+}, which could eliminate the need for phosphors in nitride-based solid state light sources. The main idea was to convert electron-hole pairs injected into the active layer in a LED die to white light directly through transitions within the energy levels of the 4f{sup n}-manifold of RE{sup 3+}. We focused on the following materials: Eu{sup 3+}(red), Tb{sup 3+}(green), Er{sup 3+}(green), Dy{sup 3+}(yellow) and Tm{sup 3+}(blue) in AlN, GaN and alloys of AlN and GaN. Our strategy was to explore candidate materials in powder form first, and then study their behavior in thin films. Thin films of these materials were to be deposited on sapphire substrates using pulsed laser deposition (PLD) and metal organic vapor phase epitaxy (MOVPE). The photo- and cathode-luminescence measurements of these materials were used to investigate their suitability for white light generation. The project proceeded along this route with minor modifications needed to produce better materials and to expedite our progress towards the final goal. The project made the following accomplishments: (1) red emission from Eu{sup 3+}, green from Tb{sup 3+}, yellow from Dy{sup 3+} and blue from Tm{sup 3+} in AlN powders; (2) red emission from Eu{sup 3+} and green emission from Tb{sup 3+} in GaN powder; (3) red emission from Eu{sup 3+} in alloys of GaN and AlN; (4) green emission from Tb{sup 3+} in GaN thin films by PLD; (5) red emission from Eu{sup 3+} and Tb{sup 3+} in GaN thin films deposited by MOVPE; (6) energy transfer from host to RE{sup 3+}; (7) energy transfer from Tb{sup 3+} to Eu{sup 3+} in AlN powders; (8) emission from AlN powder samples codoped with (Eu{sup 3+} ,Tb{sup 3+} ) and (Dy{sup 3+}, Tm{sup 3+}); and (9) white emission from AlN codoped with Dy{sup 3+} and Tm{sup 3+}. We also extensively studied the stabilities of rare earth ions in GaN, and the nature of oxygen defects in GaN and its impact on the optical properties of the host material, using first principles method. Results from these theoretical calculations together with fluorescence measurements from the materials essentially proved the underlying concepts for generating white light using RE{sup 3+}-activated nitrides. For this project, we successfully built a horizontal MOVPE reactor and used it to deposit thin films of undoped and doped nitrides of GaN and InGaN, which is a very significant achievement. Since this reactor was designed and built by in-house experts, it could be easily modified and reassembled for specific research purposes. During this study, it was successfully modified for homogeneous distribution of rare earth ions in a deposited film. It will be an ideal tool for future research involving novel thin film material concepts. We examined carefully the suitability of various metal organic precursors for incorporating RE{sup 3+}. In order to avoid oxygen contamination, several oxygen-free RE{sup 3+} precursors were identified. Both oxygen-free and oxygen- containing metal organic precursors were used for certain rare earth ions (Eu{sup 3+}, Tb{sup 3+} and Er{sup 3+}). However, the suitability of any particular type of precursor for MOVPE deposition was not established during this study, and further study is needed. More intensive research in the future is needed to improve the film quality, and eliminate the separation of rare earth oxide phases during the deposition of thin films by MOVPE. The literature in the area of the chemistry of rare earth ions in nitrides is almost nonexistent, in spite of the significant research on luminescence of RE{sup 3+} in nitrides. Consequently, MOVPE as a method of deposition of RE{sup 3+}-activated nitrides is relatively unexplored. In the following sections of this report, the ou

Jan Talbot; Kailash Mishra

2007-12-31T23:59:59.000Z

135

(Polyfluoroaryl) fluoroanions of aluminum, gallium, and indium of enhanced utility, uses thereof, and products based thereon  

DOE Patents (OSTI)

The (polyfluoroaryl)fluoroanions of aluminum, gallium, and indium are novel weakly coordinating anions which are highly fluorinated. (Polyfluoroaryl)fluoroanions of one such type contain at least one ring substituent other than fluorine. These (polyfluoroaryl)fluoroanions of aluminum, gallium, and indium have greater solubility in organic solvents, or have a coordinative ability essentially equal to or less than that of the corresponding (polyfluoroaryl)fluoroanion of aluminum, gallium, or indium in which the substituent is replaced by fluorine. Another type of new (polyfluoroaryl)fluoroanion of aluminum, gallium, and indium have 1-3 perfluorinated fused ring groups and 2-0 perfluorophenyl groups. When used as a cocatalyst in the formation of novel catalytic complexes with d- or f-block metal compounds having at least one leaving group such as a methyl group, these anions, because of their weak coordination to the metal center, do not interfere in the ethylene polymerization process, while affecting the propylene process favorably, if highly isotactic polypropylene is desired. Thus, the (polyfluoroaryl)fluoroanions of aluminum, gallium, and indium of this invention are useful in various polymerization processes such as are described.

Marks, Tobin J. (Evanston, IL); Chen, You-Xian (Midland, MI)

2001-01-01T23:59:59.000Z

136

(Polyfluoroaryl) fluoroanions of aluminum, gallium, and indium of enhanced utility, uses thereof, and products based thereon  

DOE Patents (OSTI)

The (polyfluoroaryl)fluoroanions of aluminum, gallium, and indium are novel weakly coordinating anions which are highly fluorinated. (Polyfluoroaryl)fluoroanions of one such type contain at least one ring substituent other than fluorine. These (polyfluoroaryl)fluoroanions of aluminum, gallium, and indium have greater solubility in organic solvents, or have a coordinative ability essentially equal to or less than that of the corresponding (polyfluoroaryl)fluoroanion of aluminum, gallium, or indium in which the substituent is replaced by fluorine. Another type of new (polyfluoroaryl)fluoroanion of aluminum, gallium, and indium have 1-3 perfluorinated fused ring groups and 2-0 perfluorophenyl groups. When used as a cocatalyst in the formation of novel catalytic complexes with d- or f-block metal compounds having at least one leaving group such as a methyl group, these anions, because of their weak coordination to the metal center, do not interfere in the ethylene polymerization process, while affecting the propylene process favorably, if highly isotactic polypropylene is desired. Thus, the (polyfluoroaryl)fluoroanions of aluminum, gallium, and indium of this invention are useful in various polymerization processes such as are described.

Marks, Tobin J. (Evanston, IL); Chen, You-Xian (Midland, MI)

2002-01-01T23:59:59.000Z

137

Electron backscatter diffraction of plutonium-gallium alloys  

Science Conference Proceedings (OSTI)

At Los Alamos National Laboratory a recent experimental technique has been developed to characterize reactive metals, including plutonium arid cerium, using electron backscatter diffraction (EBSD). Microstructural characterization of plutonium and its alloys by EBSD had been previously elusive primarily because of the extreme toxicity and rapid surface oxidation rate associated with plutonium metal. The experimental techniques, which included ion-sputtering the metal surface using a scanning auger microprobe (SAM) followed by vacuum transfer of the sample from the SAM to the scanning electron microscope (SEM), used to obtain electron backscatter diffraction Kikuchi patterns (EBSPs) and orientation maps for plutonium-gallium alloys are described and the initial microstructural observations based on the analysis are discussed. Combining the SEM and EBSD observations, the phase transformation behavior between the {delta} and {var_epsilon} structures was explained. This demonstrated sample preparation and characterization technique is expected to be a powerful means to further understand phase transformation behavior, orientation relationships, and texlure in the complicated plutonium alloy systems.

Boehlert, C. J. (Carl J.); Zocco, T. G. (Thomas G.); Schulze, R. K. (Roland K.); Mitchell, J. N. (Jeremy N.); Pereyra, R. A. (Ramiro A.)

2002-01-01T23:59:59.000Z

138

High efficiency III-nitride light-emitting diodes  

DOE Patents (OSTI)

Tailored doping of barrier layers enables balancing of the radiative recombination among the multiple-quantum-wells in III-Nitride light-emitting diodes. This tailored doping enables more symmetric carrier transport and uniform carrier distribution which help to reduce electron leakage and thus reduce the efficiency droop in high-power III-Nitride LEDs. Mitigation of the efficiency droop in III-Nitride LEDs may enable the pervasive market penetration of solid-state-lighting technologies in high-power lighting and illumination.

Crawford, Mary; Koleske, Daniel; Cho, Jaehee; Zhu, Di; Noemaun, Ahmed; Schubert, Martin F; Schubert, E. Fred

2013-05-28T23:59:59.000Z

139

Cordierite silicon nitride filters. Final report  

SciTech Connect

The objective of this project was to develop a silicon nitride based crossflow filter. This report summarizes the findings and results of the project. The project was phased with Phase I consisting of filter material development and crossflow filter design. Phase II involved filter manufacturing, filter testing under simulated conditions and reporting the results. In Phase I, Cordierite Silicon Nitride (CSN) was developed and tested for permeability and strength. Target values for each of these parameters were established early in the program. The values were met by the material development effort in Phase I. The crossflow filter design effort proceeded by developing a macroscopic design based on required surface area and estimated stresses. Then the thermal and pressure stresses were estimated using finite element analysis. In Phase II of this program, the filter manufacturing technique was developed, and the manufactured filters were tested. The technique developed involved press-bonding extruded tiles to form a filter, producing a monolithic filter after sintering. Filters manufactured using this technique were tested at Acurex and at the Westinghouse Science and Technology Center. The filters did not delaminate during testing and operated and high collection efficiency and good cleanability. Further development in areas of sintering and filter design is recommended.

Sawyer, J.; Buchan, B. [Acurex Environmental Corp., Mountain View, CA (United States); Duiven, R.; Berger, M. [Aerotherm Corp., Mountain View, CA (United States); Cleveland, J.; Ferri, J. [GTE Products Corp., Towanda, PA (United States)

1992-02-01T23:59:59.000Z

140

Ultralow nonalloyed Ohmic contact resistance to self aligned N-polar GaN high electron mobility transistors by In(Ga)N regrowth  

Science Conference Proceedings (OSTI)

Ultralow Ohmic contact resistance and a self-aligned device structure are necessary to reduce the effect of parasitic elements and obtain higher f{sub t} and f{sub max} in high electron mobility transistors (HEMTs). N-polar (0001) GaN HEMTs, offer a natural advantage over Ga-polar HEMTs, in terms of contact resistance since the contact is not made through a high band gap material [Al(Ga)N]. In this work, we extend the advantage by making use of polarization induced three-dimensional electron-gas through regrowth of graded InGaN and thin InN cap in the contact regions by plasma (molecular beam epitaxy), to obtain an ultralow Ohmic contact resistance of 27 OMEGA mum to a GaN 2DEG.

Dasgupta, Sansaptak; Nidhi,; Brown, David F.; Wu, Feng; Keller, Stacia; Speck, James S.; Mishra, Umesh K. [Department of ECE, University of California, Santa Barbara, California 93106 (United States) and Department of Materials, University of California, Santa Barbara, California 93106 (United States)

2010-04-05T23:59:59.000Z

Note: This page contains sample records for the topic "gallium nitride ingan" 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

Bright Lights and Even Brighter Ideas | Department of Energy  

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

nitride (InGaN) samples to a thickness of just 20 nanometers to prepare them for electron microscopy. | Photo courtesy of Brookhaven National Laboratory. Kim Kisslinger, a...

142

Effect of magnetic field on the mechanical properties of magnetostrictive iron-gallium nanowires  

SciTech Connect

This study experimentally investigates the elastic properties of individual iron-gallium nanowires with and without an applied magnetic bias field. The experiments were conducted with a custom manipulator stage designed for use within a scanning electron microscope, where nanowires were mechanically tested both statically and dynamically. Experiments were also performed in the presence of a 20 Oe dc magnetic field in order to identify any variation in wire properties. The results suggest that iron-gallium nanowires possess an elastic modulus very similar to the macroscale value, tensile strengths of more than double the bulk material, and minor magnetic field induced stiffening at low stresses.

Downey, Patrick R.; Flatau, Alison B. [Department of Aerospace Engineering, University of Maryland, 3181 Martin Hall, College Park, Maryland 20742 (United States); McGary, Patrick D.; Stadler, Bethanie J. H. [Department of Electrical and Computer Engineering, University of Minnesota, 200 Union St., Minneapolis, Minnesota 55455 (United States)

2008-04-01T23:59:59.000Z

143

Iron-Nitride Alloy Magnets: Transformation Enabled Nitride Magnets Absent Rare Earths (TEN Mare)  

Science Conference Proceedings (OSTI)

REACT Project: Case Western is developing a highly magnetic iron-nitride alloy to use in the magnets that power electric motors found in EVs and renewable power generators. This would reduce the overall price of the motor by eliminating the expensive imported rare earth minerals typically found in today’s best commercial magnets. The iron-nitride powder is sourced from abundant and inexpensive materials found in the U.S. The ultimate goal of this project is to demonstrate this new magnet system, which contains no rare earths, in a prototype electric motor. This could significantly reduce the amount of greenhouse gases emitted in the U.S. each year by encouraging the use of clean alternatives to oil and coal.

None

2012-01-01T23:59:59.000Z

144

Processing and characterization of silicon nitride nanofiber paper  

Science Conference Proceedings (OSTI)

Papers of silicon nitride nanofibers were synthesized by a carbothermal reduction process. These nanofiber papers were synthesized in situ and did not require a secondary processing step. The process utilized silica nanopowders and silica gel as the ...

Kei-Peng Jen, Ronald Warzoha, Ji Guo, Michael Tang, Sridhar Santhanam

2013-01-01T23:59:59.000Z

145

Studies on Plasma Surface Nitriding of Interstitial Free Steel  

Science Conference Proceedings (OSTI)

Plasma nitriding has been carried out at an applied pressure of 5 mbar using a gas mixture of nitrogen (20 %) and hydrogen (80 %) at 450oC for 1-5 h.

146

Molybdenum enhanced low-temperature deposition of crystalline silicon nitride  

DOE Patents (OSTI)

A process for chemical vapor deposition of crystalline silicon nitride is described which comprises the steps of: introducing a mixture of a silicon source, a molybdenum source, a nitrogen source, and a hydrogen source into a vessel containing a suitable substrate; and thermally decomposing the mixture to deposit onto the substrate a coating comprising crystalline silicon nitride containing a dispersion of molybdenum silicide. 5 figures.

Lowden, R.A.

1994-04-05T23:59:59.000Z

147

Low-loss binder for hot pressing boron nitride  

DOE Patents (OSTI)

This report describes an invention utilizing Borazine derivatives as low-loss binders and precursors for making ceramic boron nitirde structures. The derivative forms the same composition as the boron nitride starting material, thereby filling the voids with the same boron nitride material upon forming and hot pressing. The derivatives have a further advantage of being low in carbon thus resulting in less volatile byproduct that can result in bubble formation during pressing.

Maya, L.

1989-06-02T23:59:59.000Z

148

Feasibility of breeding in hard spectrum boiling water reactors with oxide and nitride fuels  

E-Print Network (OSTI)

This study assesses the neutronic, thermal-hydraulic, and fuel performance aspects of using nitride fuel in place of oxides in Pu-based high conversion light water reactor designs. Using the higher density nitride fuel ...

Feng, Bo, Ph. D. Massachusetts Institute of Technology

2011-01-01T23:59:59.000Z

149

Preconceptual design for separation of plutonium and gallium by ion exchange  

SciTech Connect

The disposition of plutonium from decommissioned nuclear weapons, by incorporation into commercial UO{sub 2}-based nuclear reactor fuel, is a viable means to reduce the potential for theft of excess plutonium. This fuel, which would be a combination of plutonium oxide and uranium oxide, is referred to as a mixed oxide (MOX). Following power generation in commercial reactors with this fuel, the remaining plutonium would become mixed with highly radioactive fission products in a spent fuel assembly. The radioactivity, complex chemical composition, and large size of this spent fuel assembly, would make theft difficult with elaborate chemical processing required for plutonium recovery. In fabricating the MOX fuel, it is important to maintain current commercial fuel purity specifications. While impurities from the weapons plutonium may or may not have a detrimental affect on the fuel fabrication or fuel/cladding performance, certifying the effect as insignificant could be more costly than purification. Two primary concerns have been raised with regard to the gallium impurity: (1) gallium vaporization during fuel sintering may adversely affect the MOX fuel fabrication process, and (2) gallium vaporization during reactor operation may adversely affect the fuel cladding performance. Consequently, processes for the separation of plutonium from gallium are currently being developed and/or designed. In particular, two separation processes are being considered: (1) a developmental, potentially lower cost and lower waste, thermal vaporization process following PuO{sub 2} powder preparation, and (2) an off-the-shelf, potentially higher cost and higher waste, aqueous-based ion exchange (IX) process. While it is planned to use the thermal vaporization process should its development prove successful, IX has been recommended as a backup process. This report presents a preconceptual design with material balances for separation of plutonium from gallium by IX.

DeMuth, S.F.

1997-09-30T23:59:59.000Z

150

Cavitation contributes substantially to tensile creep in silicon nitride  

Science Conference Proceedings (OSTI)

During tensile creep of a hot isostatically pressed (HIPed) silicon nitride, the volume fraction of cavities increases linearly with strain; these cavities produce nearly all of the measured strain. In contrast, compressive creep in the same stress and temperature range produces very little cavitation. A stress exponent that increases with stress ({dot {var_epsilon}} {proportional_to} {sigma}{sup n}, 2 < n < 7) characterizes the tensile creep response, while the compressive creep response exhibits a stress dependence of unity. Furthermore, under the same stress and temperature, the material creeps nearly 100 times faster in tension than in compression. Transmission electron microscopy (TEM) indicates that the cavities formed during tensile creep occur in pockets of residual crystalline silicate phase located at silicon nitride multigrain junctions. Small-angle X-ray scattering (SAXS) from crept material quantifies the size distribution of cavities observed in TEM and demonstrates that cavity addition, rather than cavity growth, dominates the cavitation process. These observations are in accord with a model for creep based on the deformation of granular materials in which the microstructure must dilate for individual grains t slide past one another. During tensile creep the silicon nitride grains remain rigid; cavitation in the multigrain junctions allows the silicate to flow from cavities to surrounding silicate pockets, allowing the dilation of the microstructure and deformation of the material. Silicon nitride grain boundary sliding accommodates this expansion and leads to extension of the specimen. In compression, where cavitation is suppressed, deformation occurs by solution-reprecipitation of silicon nitride.

Luecke, W.E.; Wiederhorn, S.M.; Hockey, B.J.; Krause, R.F. Jr.; Long, G.G. [National Institute of Standards and Technology, Gaithersburg, MD (United States)

1995-08-01T23:59:59.000Z

151

Device performance of in situ steam generated gate dielectric nitrided by remote plasma nitridation  

Science Conference Proceedings (OSTI)

In situ steam generated (ISSG) oxides have recently attracted interest for use as gate dielectrics because of their demonstrated reliability improvement over oxides formed by dry oxidation. [G. Minor, G. Xing, H. S. Joo, E. Sanchez, Y. Yokota, C. Chen, D. Lopes, and A. Balakrishna, Electrochem. Soc. Symp. Proc. 99-10, 3 (1999); T. Y. Luo, H. N. Al-Shareef, G. A. Brown, M. Laughery, V. Watt, A. Karamcheti, M. D. Jackson, and H. R. Huff, Proc. SPIE 4181, 220 (2000).] We show in this letter that nitridation of ISSG oxide using a remote plasma decreases the gate leakage current of ISSG oxide by an order of magnitude without significantly degrading transistor performance. In particular, it is shown that the peak normalized transconductance of n-channel devices with an ISSG oxide gate dielectric decreases by only 4% and the normalized drive current by only 3% after remote plasma nitridation (RPN). In addition, it is shown that the reliability of the ISSG oxide exhibits only a small degradation after RPN. These observations suggest that the ISSG/RPN process holds promise for gate dielectric applications. {copyright} 2001 American Institute of Physics.

Al-Shareef, H. N.; Karamcheti, A.; Luo, T. Y.; Bersuker, G.; Brown, G. A.; Murto, R. W.; Jackson, M. D.; Huff, H. R.; Kraus, P.; Lopes, D. (and others)

2001-06-11T23:59:59.000Z

152

Cooled silicon nitride stationary turbine vane risk reduction. Final report  

SciTech Connect

The purpose of this program was to reduce the technical risk factors for demonstration of air cooled silicon nitride turbine vanes. The effort involved vane prototype fabrication efforts at two U.S. based gas turbine grade silicon nitride component manufacturers. The efficacy of the cooling system was analyzed via a thermal time/temperature flow test technique previously at UTRC. By having multiple vendors work on parts fabrication, the chance of program success increased for producing these challenging components. The majority of the effort under this contract focused on developing methods for, and producing, the complex thin walled silicon nitride vanes. Components developed under this program will undergo engine environment testing within N00014-96-2-0014.

Holowczak, John

1999-12-31T23:59:59.000Z

153

Silicon nitride protective coatings for silvered glass mirrors  

DOE Patents (OSTI)

A protective diffusion barrier for metalized mirror structures is provided by a layer or coating of silicon nitride which is a very dense, transparent, dielectric material that is impervious to water, alkali, and other impurities and corrosive substances that typically attack the metal layers of mirrors and cause degradation of the mirrors' reflectivity. The silicon nitride layer can be deposited on the substrate prior to metal deposition thereon to stabilize the metal/substrate interface, and it can be deposited over the metal to encapsulate it and protect the metal from corrosion or other degradation. Mirrors coated with silicon nitride according to this invention can also be used as front surface mirrors.

Tracy, C.E.; Benson, D.K.

1984-07-20T23:59:59.000Z

154

Synthesis and Optimization of the Sintering Kinetics of Actinide Nitrides  

SciTech Connect

Research conducted for this NERI project has advanced the understanding and feasibility of nitride nuclear fuel processing. In order to perform this research, necessary laboratory infrastructure was developed; including basic facilities and experimental equipment. Notable accomplishments from this project include: the synthesis of uranium, dysprosium, and cerium nitrides using a novel, low-cost mechanical method at room temperature; the synthesis of phase pure UN, DyN, and CeN using thermal methods; and the sintering of UN and (Ux, Dy1-x)N (0.7 ? X ? 1) pellets from phase pure powder that was synthesized in the Advanced Materials Laboratory at Boise State University.

Drryl P. Butt; Brian Jaques

2009-03-31T23:59:59.000Z

155

Thermodynamic property evaluation and magnetic refrigeration cycle analysis for gadolinium gallium garnet  

SciTech Connect

Based on relevant material property data and previous model formulations, a magnetothermodynamic property map for gadolinium gallium garnet (Gd{sub 3}Ga{sub 5}O{sub 12}) was adapted for refrigeration cycle analysis in the temperature range 4-40 K and the magnetic field range 0-6 T. Employing methods similar to those previously developed for other materials and temperature ranges, assessments of limitations and relative performance were made for Carnot, ideal regenerative, and pseudo-constant field regenerative cycles. It was found that although Carnot cycle limitations on available temperature lift for gadolinium gallium garnet are not as severe as the limitations for materials previously examined, considerable improvement in cooling capacity and temperature lift combinations can be achieved by using regenerative cycles if serious loss mechanisms are avoided.

Murphy, R.W.

1994-12-01T23:59:59.000Z

156

Ammothermal Growth of Gan Substrates For Leds: High-Pressure Ammonothermal Process for Bulk Gallium Nitride Crystal Growth for Energy Efficient Commercially Competitive Lighting  

Science Conference Proceedings (OSTI)

Broad Funding Opportunity Announcement Project: The new GaN crystal growth method is adapted from that used to grow quartz crystals, which are very inexpensive and represent the second-largest market for single crystals for electronic applications (after silicon). More extreme conditions are required to grow GaN crystals and therefore a new type of chemical growth chamber was invented that is suitable for large-scale manufacturing. A new process was developed that grows GaN crystals at a rate that is more than double that of current processes. The new technology will enable GaN substrates with best-in-world quality at lowest-in-world prices, which in turn will enable new generations of white LEDs, lasers for full-color displays, and high-performance power electronics.

None

2011-01-01T23:59:59.000Z

157

Continuous Fiber Ceramic Composite (CFCC) Program: Gaseous Nitridation  

SciTech Connect

Textron has developed a mature process for the fabrication of continuous fiber ceramic composite (CFCC) tubes for application in the aluminum processing and casting industry. The major milestones in this project are System Composition; Matrix Formulation; Preform Fabrication; Nitridation; Material Characterization; Component Evaluation

R. Suplinskas G. DiBona; W. Grant

2001-10-29T23:59:59.000Z

158

Evaluation and silicon nitride internal combustion engine components  

DOE Green Energy (OSTI)

The feasibility of silicon nitride (Si[sub 3]N[sub 4]) use in internal combustion engines was studied by testing three different components for wear resistance and lower reciprocating mass. The information obtained from these preliminary spin rig and engine tests indicates several design changes are necessary to survive high-stress engine applications. The three silicon nitride components tested were valve spring retainers, tappet rollers, and fuel pump push rod ends. Garrett Ceramic Components' gas-pressure sinterable Si[sub 3]N[sub 4] (GS-44) was used to fabricate the above components. Components were final machined from densified blanks that had been green formed by isostatic pressing of GS-44 granules. Spin rig testing of the valve spring retainers indicated that these Si[sub 3]N[sub 4] components could survive at high RPM levels (9,500) when teamed with silicon nitride valves and lower spring tension than standard titanium components. Silicon nitride tappet rollers showed no wear on roller O.D. or I.D. surfaces, steel axles and lifters; however, due to the uncrowned design of these particular rollers the cam lobes indicated wear after spin rig testing. Fuel pump push rod ends were successful at reducing wear on the cam lobe and rod end when tested on spin rigs and in real-world race applications.

Voldrich, W. (Allied-Signal Aerospace Co., Torrance, CA (United States). Garrett Ceramic Components Div.)

1992-04-01T23:59:59.000Z

159

Boron nitride substrates for high-quality graphene electronics  

E-Print Network (OSTI)

Boron nitride substrates for high-quality graphene electronics C. R. Dean1,2 *, A. F. Young3 , I and J. Hone2 * Graphene devices on standard SiO2 substrates are highly disor- dered, exhibiting report the fabrication and characterization of high-quality exfoliated mono- and bilayer graphene devices

Shepard, Kenneth

160

Boron nitride substrates for high-quality graphene electronics  

E-Print Network (OSTI)

(right axis) versus gate voltage at B ÂĽ 14 T (solid line) and 8.5 T (dashed line) for monolayer grapheneBoron nitride substrates for high-quality graphene electronics C. R. Dean1,2 *, A. F. Young3 , I and J. Hone2 * Graphene devices on standard SiO2 substrates are highly disor- dered, exhibiting

Kim, Philip

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


161

BORON NITRIDE CAPACITORS FOR ADVANCED POWER ELECTRONIC DEVICES  

DOE Green Energy (OSTI)

This project fabricates long-life boron nitride/boron oxynitride thin film -based capacitors for advanced SiC power electronics with a broad operating temperature range using a physical vapor deposition (PVD) technique. The use of vapor deposition provides for precise control and quality material formation.

N. Badi; D. Starikov; C. Boney; A. Bensaoula; D. Johnstone

2010-11-01T23:59:59.000Z

162

(Polyfluoroaryl)fluoroanions of aluminum, gallium, and indium of enhanced utility, uses thereof, and products based thereon  

DOE Patents (OSTI)

The (polyfluoroaryl)fluoroanions of aluminum, gallium, and indium are novel weakly coordinating anions which are are highly fluorinated. (Polyfluoroaryl)fluoroanions of one such type contain at least one ring substituent other than fluorine. These (polyfluoroaryl)fluoroanions of aluminum, gallium, and indium have greater solubility in organic solvents, or have a coordinative ability essentially equal to or less than that of the corresponding (polyfluoroaryl)fluoroanion of aluminum, gallium, or indium in which the substituent is replaced by fluorine. Another type of new (polyfluoroaryl)fluoroanion of aluminum, gallium, and indium have 1-3 perfluorinated fused ring groups and 2-0 perfluorophenyl groups. When used as a cocatalyst in the formation of novel catalytic complexes with d- or f-block metal compounds having at least one leaving group such as a methyl group, these anions, because of their weak coordination to the metal center, do not interefere in the ethylene polymerization process, while affecting the the propylene process favorably, if highly isotactic polypropylene is desired. Thus, the (polyfluoroaryl)fluoroanions of aluminum, gallium, and indium of this invention are useful in various polymerization processes such as are described.

Marks, Tobin J. (Evanston, IL); Chen, You-Xian (Midland, MI)

2001-01-01T23:59:59.000Z

163

Gallium arsenide thin films on tungsten/graphite substrates. Phase II. Quarterly project report No. 2, December 1, 1977-February 28, 1978  

DOE Green Energy (OSTI)

The objectives of this contract are to investigate thin films of gallium arsenide on tungsten/graphite substrates and to prepare solar cells with an AM1 efficiency of 6% or higher by August 1978. Efforts during this quarter have been directed to: (1) the deposition and characterization of gallium arsenide films on tungsten/graphite substrates by the arsenic and arsine processes, (2) the construction and operation of an apparatus for the deposition of titanium dioxide films, and (3) the fabrication and evaluation of MOS solar cells on tungsten/graphite substrates. Gallium arsenide films have been deposited on tungsten/graphite substrates by the reaction of gallium, hydrogen chloride, and arsenic in a hydrogen flow. The structural and electrical properties of these films are very similar to those obtained by the arsine process. The initial stage of the deposition of gallium arsenide films on tungsten/graphite substrates has been investigated by the scanning electron microscopy.

Chu, S.S.

1978-03-01T23:59:59.000Z

164

Thin film gallium arsenide solar cell research. Third quarterly project report, September 1, 1980-November 30, 1980. [Antireflection coating  

DOE Green Energy (OSTI)

The major objective of this contract is to produce gallium arsenide solar cells of 10% conversion efficiency in films of less than 10 micrometers thick which have been deposited by chemical vapor deposition on graphite or tungsten coated graphite substrates. Major efforts during this quarter were directed to: (1) the optimization of the deposition of gallium arsenide films of 10 ..mu..m thickness or less on tungsten/graphic substrates, (2) the investigation of the effectiveness of various grain boundary passivation techniques, (3) the deposition of tantalum pentoxide by ion beam sputtering as an antireflection coating, (4) the deposition of gallium aluminium arsenide by the organometallic process, and (5) the fabrication and characterization of large area Schottky barrier type solar cells from gallium arsenide films of about 10 ..mu..m thickness. Various grain boundary passivation techniques, such as the anodic oxidation, thermal oxidation, and ruthenium treatment, have been investigated. The combination of thermal oxidation and ruthenium treatment has been used to fabricate Schottky barrier type solar cells. Large area MOS solar cells of 9 cm/sup 2/ area with AMl efficiency of 8.5% have been fabricated from ruthenium treated gallium arsenide films of 10 ..mu..m thickness. The construction of the apparatus for the deposition of gallium aluminum arsenide by the organometallic process has been completed. The deposition of good quality tantalum pentoxide film as an antireflection coating has been carried out by the ion beam sputtering technique. The short-circuit current density and AMl efficiency of the solar cells are increased by approximately 60%, with a slight increase in the open-circuit voltage. Details are presented. (WHK)

Chu, S. S.

1980-12-01T23:59:59.000Z

165

Nano-Scale Nitride-Particle Strengthened High-Temperature Ferritic ...  

Nano-Scale Nitride-Particle Strengthened High-Temperature Ferritic and Martensitic Steels Produced by a Thermo-Mechanical Treatment Process Note: The technology ...

166

L3 Hydrogen Storage in Nitrides by the Use of Ammonia as a ...  

Science Conference Proceedings (OSTI)

A37 Unconventional Method of Nitriding of 316l Austenitic Steel · A38 Role of ..... I24 The Study of Cotton Finishing by Artemsia Argyi Oil Microcapsules.

167

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

168

Kinetics for the reaction of hydrogen with a plutonium-1 weight percent gallium alloy powder  

Science Conference Proceedings (OSTI)

Kinetics for the reaction of hydrogen with plutonium-1 w/o gallium were measured using powder prepared ''in situ.'' The rates obeyed a first-order rate law and were independent of temperature from -29/degree/ to 355/degree/C. A pressure dependence proportional to P/sup //one-half/ was observed at pressures less than 1 kPa. From 1 to 70 kPa the pressure dependence rapidly decreased. Total pressure dependence could be accurately described by a Langmuir equation. Results indicate an adsorption-controlled reaction at low pressures and a reaction-controlled process at high pressure. 19 refs.

Stakebake, J.L.

1981-11-01T23:59:59.000Z

169

Method of preparing uranium nitride or uranium carbonitride bodies  

DOE Patents (OSTI)

Sintered uranium nitride or uranium carbonitride bodies having a controlled final carbon-to-uranium ratio are prepared, in an essentially continuous process, from U.sub.3 O.sub.8 and carbon by varying the weight ratio of carbon to U.sub.3 O.sub.8 in the feed mixture, which is compressed into a green body and sintered in a continuous heating process under various controlled atmospheric conditions to prepare the sintered bodies.

Wilhelm, Harley A. (Ames, IA); McClusky, James K. (Valparaiso, IN)

1976-04-27T23:59:59.000Z

170

Biegel, Osman, Yu Analysis of Aluminum-Nitride SOI HiTEC 2000 1 June 11-15, 2000  

E-Print Network (OSTI)

. Bengtsson, M. Bergh, M. Choumas, C. Olesen, and K.O. Jeppson, "Application of Aluminum Nitride Films

Biegel, Bryan

171

BridgeLux Inc former eLite Optoelectronics | Open Energy Information  

Open Energy Info (EERE)

BridgeLux Inc former eLite Optoelectronics BridgeLux Inc former eLite Optoelectronics Jump to: navigation, search Name BridgeLux Inc (former eLite Optoelectronics) Place Sunnyvale, California Zip 94086 Product Developer and provider of indium gallium nitride light emitting diodes (InGaN LEDs) for solid state lighting, mobile appliance, signage, and automotive applications. References BridgeLux Inc (former eLite Optoelectronics)[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. BridgeLux Inc (former eLite Optoelectronics) is a company located in Sunnyvale, California . References ↑ "BridgeLux Inc (former eLite Optoelectronics)" Retrieved from "http://en.openei.org/w/index.php?title=BridgeLux_Inc_former_eLite_Optoelectronics&oldid=34303

172

Dynamics of formation of photoresponse in a detector structure made of gallium arsenide  

SciTech Connect

The influence of capture effects on the characteristics of detectors of the ionizing radiation based on semi-insulating gallium arsenide is considered. Generation of nonequilibrium electrons and holes along the entire thickness of the active region was performed under illumination with an infrared light-emitting diode with a wavelength of 0.9 {mu}m. In this case, the situation emerging in the device structure under the effect of X-ray radiation or a high-energy electron beam was simulated. It is shown that the variation in the shape of the output signal with time in this case is caused by variation in the electric field profile due to the capture of holes at deep centers in gallium arsenide. An absolutely different distribution of the electric field emerges in the structure under irradiation of a semitransparent cathode of the structure with a red light-emitting diode, emission of which penetrates into the active region for mere 1 {mu}m. In this case, the transformation of the electric field is caused by the capture of electrons. Under the prolonged effect of such radiation, a space-charge-limited current mode emerges in the device.

Ayzenshtat, G. I., E-mail: ayzen@mail.tomsknet.ru; Lelekov, M. A.; Tolbanov, O. P. [Tomsk State University (Russian Federation)

2008-04-15T23:59:59.000Z

173

Anionic Gallium-Based Metal;#8722;Organic Framework and Its Sorption and Ion-Exchange Properties  

SciTech Connect

A gallium-based metal-organic framework Ga{sub 6}(C{sub 9}H{sub 3}O{sub 6}){sub 8} {center_dot} (C{sub 2}H{sub 8}N){sub 6}(C{sub 3}H{sub 7}NO){sub 3}(H{sub 2}O){sub 26} [1, Ga{sub 6}(1,3,5-BTC){sub 8} {center_dot} 6DMA {center_dot} 3DMF {center_dot} 26H{sub 2}O], GaMOF-1; BTC = benzenetricarboxylate/trimesic acid and DMA = dimethylamine, with space group I{bar 4}3d, a = 19.611(1) {angstrom}, and V = 7953.4(6) {angstrom}{sup 3}, was synthesized using solvothermal techniques and characterized by synchrotron-based X-ray microcrystal diffraction. Compound 1 contains isolated gallium tetrahedra connected by the organic linker (BTC) forming a 3,4-connected anionic porous network. Disordered positively charged ions and solvent molecules are present in the pore, compensating for the negative charge of the framework. These positively charged molecules could be exchanged with alkali-metal ions, as is evident by an ICP-MS study. The H{sub 2} storage capacity of the parent framework is moderate with a H{sub 2} storage capacity of {approx}0.5 wt % at 77 K and 1 atm.

Banerjee, Debasis; Kim, Sun Jin; Wu, Haohan; Xu, Wenqian; Borkowski, Lauren A.; Li, Jing; Parise, John B. (Kwangju); (Rutgers); (SBU)

2012-04-30T23:59:59.000Z

174

One step process for producing dense aluminum nitride and composites thereof  

DOE Patents (OSTI)

A one step combustion process for the synthesis of dense aluminum nitride compositions is disclosed. The process comprises igniting pure aluminum powder in a nitrogen atmosphere at a pressure of about 1000 atmospheres or higher. The process enables the production of aluminum nitride bodies to be formed directly in a mold of any desired shape.

Holt, J. Birch (San Jose, CA); Kingman, Donald D. (Danville, CA); Bianchini, Gregory M. (Livermore, CA)

1989-01-01T23:59:59.000Z

175

Development of metal etch mask by single layer lift-off for silicon nitride photonic crystals  

Science Conference Proceedings (OSTI)

We present a method for fabrication of nanoscale patterns in silicon nitride (SiN) using a hard chrome mask formed by metal liftoff with a negative ebeam resists (maN-2401). This approach enables fabrication of a robust etch mask without the need for ... Keywords: Metal liftoff, Nanofabrication, Nanophotonics, Photonic crystals (PC), Silicon nitride (SiN)

Kang-mook Lim; Shilpi Gupta; Chad Ropp; Edo Waks

2011-06-01T23:59:59.000Z

176

Hard and elastic amorphous carbon nitride thin films studied by 13 C nuclear magnetic  

E-Print Network (OSTI)

Hard and elastic amorphous carbon nitride thin films studied by 13 C nuclear magnetic resonance bonding of hard and elastic amorphous carbon nitride (a-CNx) thin films was examined using solid-state 13 on Si 001 substrates at 300 °C. Nanoindentation tests reveal a recovery of 80%, a hardness of 5 GPa

Reilly, Anne

177

Microwave Nitridation of Sintered Reaction Bonded Silicon Parts for Natural Gas Fueled Diesel Engines  

DOE Green Energy (OSTI)

This cooperative project was a joint development program between Eaton Corporation and Lockheed Martin Energy Research (LMER). Cooperative work was of benefit to both parties. ORNL was able to assess up-scale of the microwave nitridation process using a more intricate-shaped part designed for application in advanced diesel engines. Eaton Corporation mined access to microwave facilities and expertise for the nitridation of SRBSN materials. The broad objective of the CRADA established with Eaton Corporation and ORNL was to develop cost-effective silicon nitride ceramics compared to the current materials available. The following conclusions can be made from the work performed under the CRADA: (1) Demonstrated that the binder burnout step can be incorporated into the SRBSN processing in the microwave furnace. (2) Scale-up of the microwave nitridation process using Eaton Corporation parts showed that the nitridation weight gains were essentially identical to those obtained by conventional heating. (3) Combined nitridation and sintering processes using silicon nitride beads as packing powders results in degradation of the mechanical properties. (4) Gelcasting of silicon nitride materials using Eaton Si mixtures was demonstrated.

Edler, J.; Kiggans, J.O.; Suman, A.W.; Tiegs, T.N.

1999-01-01T23:59:59.000Z

178

Ultra-thin ohmic contacts for p-type nitride light emitting devices  

DOE Patents (OSTI)

A semiconductor based Light Emitting Device (LED) can include a p-type nitride layer and a metal ohmic contact, on the p-type nitride layer. The metal ohmic contact can have an average thickness of less than about 25 .ANG. and a specific contact resistivity less than about 10.sup.-3 ohm-cm.sup.2.

Raffetto, Mark (Raleigh, NC); Bharathan, Jayesh (Cary, NC); Haberern, Kevin (Cary, NC); Bergmann, Michael (Chapel Hill, NC); Emerson, David (Chapel Hill, NC); Ibbetson, James (Santa Barbara, CA); Li, Ting (Ventura, CA)

2012-01-03T23:59:59.000Z

179

Process for making boron nitride using sodium cyanide and boron phosphate  

DOE Patents (OSTI)

This is a very simple process for making boron nitride by mixing sodium cyanide and boron phosphate and heating the mixture in an inert atmosphere until a reaction takes place. The product is a white powder of boron nitride that can be used in applications that require compounds that are stable at high temperatures and that exhibit high electrical resistance.

Bamberger, C.E.

1987-02-27T23:59:59.000Z

180

Mesoporous TiO2 spheres with a nitridated conducting layer  

Science Conference Proceedings (OSTI)

Nitridated TiO2 mesoporous spheres have been synthesized by hydrothermal processing followed by post-nitridation with NH3. Characterization data reveal a nitridated conducting layer, in addition to a mesoporous, and nanosized building-block morphology resulting in a large surface area. The samples have an average pore size and surface area of, respectively, 10 nm and 87 m2/g. The nitridated TiO2 mesoporous spheres exhibit a high capacity of > 200 mAh/g with good cyclability and high rate capability, as the nitridated conducting layer and favorable morphology of nanosized spheres provides good electrical contact, accommodates cycling induced strain smoothly, and facilitates lithium-ion diffusion.

Yoon, Sukeun [ORNL; Bridges, Craig A [ORNL; Unocic, Raymond R [ORNL; Paranthaman, Mariappan Parans [ORNL

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "gallium nitride ingan" 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

Single event upsets in gallium arsenide pseudo-complementary MESFET logic  

SciTech Connect

An introduction to gallium arsenide (GaAs) Pseudo-Complementary MESFET Logic (PCML) circuits is presented. PCML was developed to reduce the sensitivity of high-speed GaAs logic to radiation-induced single event upsets (SEUs). Experiments for testing the single-event upset (SEU) sensitivity of GaAs PCML integrated circuits (ICs) are described. The results of the experiments are analyzed. This new type of high-speed, low-power, GaAs logic provides decreased sensitivity to SEUs compared to more traditional circuit designs such as Directly-Coupled FET Logic (DCFL). PCML is fully compatible with existing GaAs E/D MESFET fabrication processes, such as those commonly used to make DCFL.

Fouts, D.J.; Wolfe, K.; Van Dyk, S.E. [Naval Postgraduate School, Monterey, CA (United States). Dept. of Electrical and Computer Engineering; Weatherford, T.R. [SFA Inc., Landover, MD (United States); McMorrow, D.; Melinger, J.S.; Tran, L.H.; Campbell, A.B. [Naval Research Lab., Washington, DC (United States)

1995-12-01T23:59:59.000Z

182

Electrical effect of titanium diffusion on amorphous indium gallium zinc oxide  

Science Conference Proceedings (OSTI)

In this work, thermal diffusion phenomenon of Ti into amorphous indium gallium zinc oxide ({alpha}-IGZO) was carefully investigated with secondary ion mass spectroscopy, I-V, and R{sub s} measurement systems and HSC chemistry simulation tool. According to the experimental and simulated results, the diffused Ti atoms were easily oxidized due to its lowest oxidation free energy. Since oxygen atoms were decomposed from the {alpha}-IGZO during the oxidation of Ti, the number of oxygen vacancies working as electron-donating sites in {alpha}-IGZO was dramatically increased, contributing to the decrease of resistivity ({rho}) from 1.96 {Omega} cm (as-deposited {alpha}-IGZO) to 1.33 Multiplication-Sign 10{sup -3}{Omega} cm (350 Degree-Sign C annealed {alpha}-IGZO).

Choi, Seung-Ha [School of Electronic and Electrical Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Development Group of Oxide Semiconductor, Samsung Display, Yongin 446-711 (Korea, Republic of); Jung, Woo-Shik [Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States); Park, Jin-Hong [School of Electronic and Electrical Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

2012-11-19T23:59:59.000Z

183

Outdoor Performance of a Thin-Film Gallium-Arsenide Photovoltaic Module  

SciTech Connect

We deployed a 855 cm2 thin-film, single-junction gallium arsenide (GaAs) photovoltaic (PV) module outdoors. Due to its fundamentally different cell technology compared to silicon (Si), the module responds differently to outdoor conditions. On average during the test, the GaAs module produced more power when its temperature was higher. We show that its maximum-power temperature coefficient, while actually negative, is several times smaller in magnitude than that of a Si module used for comparison. The positive correlation of power with temperature in GaAs is due to temperature-correlated changes in the incident spectrum. We show that a simple correction based on precipitable water vapor (PWV) brings the photocurrent temperature coefficient into agreement with that measured by other methods and predicted by theory. The low operating temperature and small temperature coefficient of GaAs give it an energy production advantage in warm weather.

Silverman, T. J.; Deceglie, M. G.; Marion, B.; Cowley, S.; Kayes, B.; Kurtz, S.

2013-06-01T23:59:59.000Z

184

Atomistic model of helium bubbles in gallium-stabilized plutonium alloys  

Science Conference Proceedings (OSTI)

The varying thermodynamic stability of gallium- (Ga-) stabilized plutonium (Pu) alloys with temperature affords a unique setting for the development of self-irradiation damage. Here, fundamental characteristics of helium (He) bubbles in these alloys with respect to temperature, gallium concentration, and He-to-vacancy ratio are modeled at the atomistic level with a modified embedded atom potential that takes account of this varying stability. Aside from the bubbles themselves, the surrounding matrix material is single-crystal metal or alloy. As a function of temperature, with a 2:1 He-to-vacancy ratio in a 5-at. % Ga fcc lattice, a 1.25-nm bubble is very stable up to about 1000 K. At 1000 K, the bubble distorts the surrounding lattice and precipitates a liquid zone, as is consistent with the phase diagram for the model material. Between 300 and 500 K, this same bubble relaxes slightly through interstitial emission. At 300 K, with a 2:1 He-to-vacancy ratio in a 2.5-at. % Ga fcc lattice, the Ga stabilization is less effective in the model to the point where the bubble distorts the local lattice and expands significantly. Similarly, at 300 K, if the He-to-vacancy ratio is increased to 3:1, there is significant local lattice distortion, as well as ejection of some He atoms into the lattice. The formation of new bubbles is not observed, because those events take place on a longer time scale than can be simulated with the present approach.

Valone, S. M.; Baskes, M. I. [Materials Science and Technology Division and Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Martin, R. L. [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2006-06-01T23:59:59.000Z

185

Preparation of copper-indium-gallium-diselenide precursor films by electrodeposition for fabricating high efficiency solar cells  

DOE Patents (OSTI)

A photovoltaic cell exhibiting an overall conversion efficiency of 13.6% is prepared from a copper-indium-gallium-diselenide precursor thin film. The film is fabricated by first simultaneously electrodepositing copper, indium, gallium, and selenium onto a glass/molybdenum substrate (12/14). The electrodeposition voltage is a high frequency AC voltage superimposed upon a DC voltage to improve the morphology and growth rate of the film. The electrodeposition is followed by physical vapor deposition to adjust the final stoichiometry of the thin film to approximately Cu(In.sub.1-n Ga.sub.x)Se.sub.2, with the ratio of Ga/(In+Ga) being approximately 0.39.

Bhattacharya, Raghu N. (Littleton, CO); Hasoon, Falah S. (Arvada, CO); Wiesner, Holm (Golden, CO); Keane, James (Lakewood, CO); Noufi, Rommel (Golden, CO); Ramanathan, Kannan (Golden, CO)

1999-02-16T23:59:59.000Z

186

The design, construction, and testing of a nuclear fuel rod thermal simulation system to study gallium/Zircaloy interactions  

E-Print Network (OSTI)

The presence of gallium in weapons grade plutonium has raised many questions concerning its use in light water reactor (LWR) fuel rods. The biggest concern is that the gallium will migrate down the thermal gradient in the fuel rod and deposit on the inner surface of the clad, which could cause it to fail. In order to study these effects, a fuel rod thermal simulation system (FRTSS) has been developed to recreate the shape and magnitude of the temperature profile in pressurized water reactor (PWR) fuel rods. The system uses electrically heated simulated fuel rods inside of a large, natural convection heat exchanger that uses lead-bismuth eutectic (LBE) (45 <% Pb, 55 <% Bi) as the working fluid. The simulated rods consist of small diameter electric heaters, annular pellets of depleted uranium/cerium oxide doped with approximately 10 ppm of gallium, a small helium filled gap, and generic Zircaloy IV cladding. The system is controlled through a computer-based data acquisition system that is used to record temperature data and operate the various pieces of equipment. A simple mathematical model was used to design the heat exchanger and predict the temperature profile within the simulated rods. Results from system tests indicated that the mathematical model was capable of predicting heater surface temperatures within 6.15% +/- 1.82% and clad outer surface temperatures within 1.91% +/- 4.46%. In addition, the tests also revealed that the system could accurately simulate the temperature profiles of operating PWR fuel rods. Consequently, the FRTSS provides a safe and effective means for studying gallium migration in the fuel pellets and its subsequent interactions with Zircaloy IV.

Allison, Christopher Curtis

1999-01-01T23:59:59.000Z

187

Reference Data for the Density and Viscosity of Liquid Cadmium, Cobalt, Gallium, Indium, Mercury, Silicon, Thallium, and Zinc  

Science Conference Proceedings (OSTI)

The available experimental data for the density and viscosity of liquid cadmium, cobalt, gallium, indium, mercury, silicon, thallium, and zinc have been critically examined with the intention of establishing both a density and a viscosity standard. All experimental data have been categorized into primary and secondary data according to the quality of measurement, the technique employed and the presentation of the data, as specified by a series of criteria. The proposed standard reference correlations for the density of liquid cadmium, cobalt, gallium, indium, silicon, thallium, and zinc are characterized by percent deviations at the 95% confidence level of 0.6, 2.1, 0.4, 0.5, 2.2, 0.9, and 0.7, respectively. In the case of mercury, since density reference values already exist, no further work was carried out. The standard reference correlations for the viscosity of liquid cadmium, cobalt, gallium, indium, mercury, silicon, thallium, and zinc are characterized by percent deviations at the 95% confidence level of 9.4, 14.0, 13.5, 2.1, 7.3, 15.7, 5.1, and 9.3, respectively.

Assael, Marc J.; Armyra, Ivi J.; Brillo, Juergen; Stankus, Sergei V.; Wu Jiangtao; Wakeham, William A. [Chemical Engineering Department, Aristotle University, 54124 Thessaloniki (Greece); Institut fuer Materialphysik im Weltraum, Deutsches Zentrum fuer Luft- und Raumfahrt, 51170 Koeln (Germany); Kutateladze Institute of Thermophysics, Siberian Brunch of the Russian Academy of Sciences, Lavrentyev ave. 1, 630090 Novosibirsk (Russian Federation); Center of Thermal and Fluid Science, School of Energy and Power Engineering, Xi'an Jiaotong University, Shaanxi 710049 (China); Chemical Engineering Department, Imperial College, London SW7 2BY (United Kingdom)

2012-09-15T23:59:59.000Z

188

Evaluation of critical materials for five advanced design photovoltaic cells with an assessment of indium and gallium  

DOE Green Energy (OSTI)

The objective of this study is to identify potential material supply constraints due to the large-scale deployment of five advanced photovoltaic (PV) cell designs, and to suggest strategies to reduce the impacts of these production capacity limitations and potential future material shortages. This report presents the results of the screening of the five following advanced PV cell designs: polycrystalline silicon, amorphous silicon, cadmium sulfide/copper sulfide frontwall, polycrystalline gallium arsenide MIS, and advanced concentrator-500X. Each of these five cells is screened individually assuming that they first come online in 1991, and that 25 GWe of peak capacity is online by the year 2000. A second computer screening assumes that each cell first comes online in 1991 and that each cell has 5 GWe of peak capacity by the year 2000, so that the total online cpacity for the five cells is 25 GWe. Based on a review of the preliminary basline screening results, suggestions were made for varying such parameters as the layer thickness, cell production processes, etc. The resulting PV cell characterizations were then screened again by the CMAP computer code. Earlier DOE sponsored work on the assessment of critical materials in PV cells conclusively identtified indium and gallium as warranting further investigation as to their availability. Therefore, this report includes a discussion of the future availability of gallium and indium. (WHK)

Watts, R.L.; Gurwell, W.E.; Jamieson, W.M.; Long, L.W.; Pawlewicz, W.T.; Smith, S.A.; Teeter, R.R.

1980-05-01T23:59:59.000Z

189

Structural tuning of residual conductivity in highly mismatched III-V layers  

DOE Patents (OSTI)

A new process to control the electrical conductivity of gallium nitride layers grown on a sapphire substrate has been developed. This process is based on initially coating the sapphire substrate with a thin layer of aluminum nitride, then depositing the gallium nitride thereon. This process allows one to controllably produce gallium nitride layers with resistivity varying over as much as 10 orders of magnitude, without requiring the introduction and activation of suitable dopants.

Han, Jung (Albuquerque, NM); Figiel, Jeffrey J. (Albuquerque, NM)

2002-01-01T23:59:59.000Z

190

Boron-Nitride (BN) Nanotubes (BNNT) at TJNAF| U.S. DOE Office of Science  

Office of Science (SC) Website

Boron-Nitride (BN) Nanotubes (BNNT) at Boron-Nitride (BN) Nanotubes (BNNT) at TJNAF Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff Archives SBIR/STTR Applications of Nuclear Science and Technology Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: sc.np@science.doe.gov More Information » Spinoff Archives Boron-Nitride (BN) Nanotubes (BNNT) at TJNAF Print Text Size: A A A RSS Feeds FeedbackShare Page Application/instrumentation: Boron-Nitride (BN) Nanotubes (BNNT) Developed at: Jefferson Lab Free Electron Facility Developed in: 2008-2011

191

Method of enhancing the wettability of boron nitride for use as an electrochemical cell separator  

DOE Patents (OSTI)

A felt or other fabric of boron nitride suitable for use as an interelectrode separator within an electrochemical cell is wetted with a solution containing a thermally decomposable organic salt of an alkaline earth metal. An aqueous solution of magnesium acetate is the preferred solution for this purpose. After wetting the boron nitride, the solution is dried by heating at a sufficiently low temperature to prevent rapid boiling and the creation of voids within the separator. The dried material is then calcined at an elevated temperature in excess of 400/sup 0/C to provide a coating of an oxide of magnesium on the surface of the boron nitride fibers. A fabric or felt of boron nitride treated in this manner is easily wetted by molten electrolytic salts, such as the alkali metal halides or alkaline earth metal halides, that are used in high temperature, secondary electrochemical cells.

McCoy, L.R.

1981-01-23T23:59:59.000Z

192

Optoelectronic Properties in Monolayers of Hybridized Graphene and Hexagonal Boron Nitride  

E-Print Network (OSTI)

We explain the nature of the electronic energy gap and optical absorption spectrum of carbon–boron-nitride (CBN) monolayers using density functional theory, GW and Bethe-Salpeter calculations. The band structure and the ...

Bernardi, Marco

193

Method of nitriding, carburizing, or oxidizing refractory metal articles using microwaves  

DOE Patents (OSTI)

A method of nitriding an article of refractory-nitride-forming metal or metalloids. A consolidated metal or metalloid article is placed inside a microwave oven and nitrogen containing gas is introduced into the microwave oven. The metal or metalloid article is heated to a temperature sufficient to react the metal or metalloid with the nitrogen by applying a microwave energy within the microwave oven. The metal or metalloid article is maintained at that temperature for a period of time sufficient to convert the article of metal or metalloid to an article of refractory nitride. in addition, a method of applying a coating, such as a coating of an oxide, a carbide, or a carbo-nitride, to an article of metal or metalloid by microwave heating.

Holcombe, Cressie E. (Knoxville, TN); Dykes, Norman L. (Oak Ridge, TN); Tiegs, Terry N. (Lenoir City, TN)

1992-01-01T23:59:59.000Z

194

Method of nitriding, carburizing, or oxidizing refractory metal articles using microwaves  

DOE Patents (OSTI)

A method of nitriding an article of refractory-nitride-forming metal or metalloids. A consolidated metal or metalloid article is placed inside a microwave oven and nitrogen containing gas is introduced into the microwave oven. The metal or metalloid article is heated to a temperature sufficient to react the metal or metalloid with the nitrogen by applying a microwave energy within the microwave oven. The metal or metalloid article is maintained at that temperature for a period of time sufficient to convert the article of metal or metalloid to an article of refractory nitride. in addition, a method of applying a coating, such as a coating of an oxide, a carbide, or a carbo-nitride, to an article of metal or metalloid by microwave heating.

Holcombe, C.E.; Dykes, N.L.; Tiegs, T.N.

1992-10-13T23:59:59.000Z

195

Process for preparing transition metal nitrides and transition metal carbonitrides and their reaction intermediates  

DOE Patents (OSTI)

Disclosed is a process for making ammonolytic precursors to nitride and carbonitride ceramics. Extreme reaction conditions are not required and the precursor is a powder-like substance that produces ceramics of improved purity and morphology upon pyrolysis.

Maya, L.

1986-12-09T23:59:59.000Z

196

Electronic structure analyses and activation studies of a dinitrogen-derived terminal nitride of molybdenum  

E-Print Network (OSTI)

Chapter 1: Complexes obtained by electrophilic attack on a dinitrogen-derived terminal molybdenum nitride: Electronic structure analysis by solid state CP/MAS ą?N NMR in combination ... Chapter 2. Carbene chemistry in the ...

Sceats, Emma Louise, 1978-

2004-01-01T23:59:59.000Z

197

Recent development of the synthesis and engineering applications of one-dimensional boron nitride nanomaterials  

Science Conference Proceedings (OSTI)

One-dimensional (1D) nanomaterials with novel photoelectric, magnetic, mechanical, and electronic transport properties have long been the research focus throughout the world. Herein, the recent achievements in preparation of 1D boron nitride nanomaterials, ...

Changhui Sun; Hongxiao Yu; Liqiang Xu; Qiang Ma; Yitai Qian

2010-01-01T23:59:59.000Z

198

Spin current switching and spin-filtering effects in Mn-doped boron nitride nanoribbons  

Science Conference Proceedings (OSTI)

The spin transport properties are investigated by means of the first principle approach for boron nitride nanoribbons with one or two substitutional Mn impurities, connected to graphene electrodes. The spin current polarization is evaluated using the ...

G. A. Nemnes

2012-01-01T23:59:59.000Z

199

Proton exchange membrane fuel cells with chromium nitride nanocrystals as electrocatalysts  

E-Print Network (OSTI)

S. Srinivasan, V. Antonucci, Fuel Cells 1, 133 (2001). 15 Y.Proton exchange membrane fuel cells with chromium nitridePolymer electrolyte membrane fuel cells (PEMFCs) are energy

Zhong, Hexiang; Chen, Xiaobo; Zhang, Huamin; Wang, Meiri; Mao, Samuel S.

2007-01-01T23:59:59.000Z

200

Nitride III-V Activities at Sandia National Labs  

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

Lighting: Lighting: Synergisms with Office of Science Materials Programs Jerry A. Simmons Semiconductor Materials and Device Sciences Sandia National Laboratories March 13, 2001 EMaCC Meeting OUTLINE *Brief overview of prospects & promise of SSL *National Initiative *Grand Challenge LDRD at Sandia *BES-supported activities at Sandia provided core capabilities *Other NS applications of nitride materials science Will only discuss inorganic materials and devices here. Major motivation for SSL is energy savings: lighting is large fraction of energy consumption 1 10 100 1000 1970 1980 1990 2000 2010 2020 Energy Electricity Illumination (assuming 20% of electricity) Projected WORLD Energy Consumption (Quads) Year 400 Quads 130 Quads 25 Quads 1998 1970 1980 1990 2000 2010 2020 Energy Electricity Illumination

Note: This page contains sample records for the topic "gallium nitride ingan" 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

High Surface Area Molybdenum Nitride Support for Fuel Cell Electrodes  

SciTech Connect

Alternative supports for polymer electrolyte membrane fuel cells were synthesized and catalytic activity was explored using electrochemical analysis. High surface area, molybdenum nitride supports were synthesized by rapidly heating a gel of polyethyleneimine bound molybdenum in a tube furnace under a forming gas atmosphere. Subsequent disposition of platinum through an incipient wetness approach lead to dispersed crystallites of platinum on the conductive support. All the ceramic materials were characterized with XRD, SEM, TEM and electrochemical analysis. The supports without platinum are highly stable to acidic aqueous conditions and show no signs of oxygen reduction reactivity (ORR). However, once the 20 wt % platinum is added to the material, ORR activity comparable to XC72 based materials is observed.

Blackmore, Karen [Los Alamos National Laboratory (LANL); Elbaz, L [Los Alamos National Laboratory (LANL); Bauer, E D [Los Alamos National Laboratory (LANL); Brosha, Eric [Los Alamos National Laboratory (LANL); More, Karren Leslie [ORNL; Mccleskey, T [Los Alamos National Laboratory (LANL); Burrell, A [Los Alamos National Laboratory (LANL)

2011-01-01T23:59:59.000Z

202

Role of defects in III-nitride based electronics  

DOE Green Energy (OSTI)

The LDRD entitled ``Role of Defects in III-Nitride Based Devices'' is aimed to place Sandia National Laboratory at the forefront of the field of GaN materials and devices by establishing a scientific foundation in areas such as material growth, defect characterization/modeling, and processing (metalization and etching) chemistry. In this SAND report the authors summarize their studies such as (1) the MOCVD growth and doping of GaN and AlGaN, (2) the characterization and modeling of hydrogen in GaN, including its bonding, diffusion, and activation behaviors, (3) the calculation of energetic of various defects including planar stacking faults, threading dislocations, and point defects in GaN, and (4) dry etching (plasma etching) of GaN (n- and p-types) and AlGaN. The result of the first AlGaN/GaN heterojunction bipolar transistor is also presented.

HAN,JUNG; MYERS JR.,SAMUEL M.; FOLLSTAEDT,DAVID M.; WRIGHT,ALAN F.; CRAWFORD,MARY H.; LEE,STEPHEN R.; SEAGER,CARLETON H.; SHUL,RANDY J.; BACA,ALBERT G.

2000-01-01T23:59:59.000Z

203

Induction, helicity, and alpha effect in a toroidal screw flow of liquid gallium  

SciTech Connect

We investigate experimentally induction mechanisms in a screw flow of gallium in a toroidal channel. The flow is nonstationary and operated in a spin-down regime: the channel (and fluid) are initially set into solid body rotation; as the channel is stopped the fluid is set into strong helical motion by diverters located inside the channel. In this study, we put a particular emphasis on the induction generated by these helical motions, which are expected to develop over the entire range of turbulent scales. We apply an external magnetic field either perpendicular to the channel axis parallel to it. At large scales the nonlinear induction mechanisms are associated with the Parker stretch and twist effect and with the expulsion due to overall rotation. Induction mechanisms can also originate in the small scale helicity as in the alpha induction effect of mean-field magnetohydrodynamics. Our measurements yield an upper bound for the alpha coefficient, significantly lower than estimates based on dimensional analysis. We discuss the consequences of our observations for the engineering of homogeneous dynamos in the laboratory.

Stepanov, R.; Denisov, S.; Noskov, V. [Institute of Continuous Media MechanicsKorolyov 1, 614061 Perm (Russian Federation); Volk, R.; Frick, P.; Pinton, J.-F. [Laboratoire de Physique de l'Ecole Normale Superieur de Lyon, CNRS UMR5672, 46 allee d'Italie, 69007 Lyon (France)

2006-04-15T23:59:59.000Z

204

Surface Composition, Work Function, and Electrochemical Characteristics of Gallium-Doped Zinc Oxide  

Science Conference Proceedings (OSTI)

Gallium-doped zinc oxide (GZO) possesses the electric conductivity, thermal stability, and earth abundance to be a promising transparent conductive oxide replacement for indium tin oxide electrodes in a number of molecular electronic devices, including organic solar cells and organic light emitting diodes. The surface chemistry of GZO is complex and dominated by the hydrolysis chemistry of ZnO, which influences the work function via charge transfer and band bending caused by adsorbates. A comprehensive characterization of the surface chemical composition and electrochemical properties of GZO electrodes is presented, using both solution and surface adsorbed redox probe molecules. The GZO surface is characterized using monochromatic X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy after the following pretreatments: (i) hydriodic acid etch, (ii) potassium hydroxide etch, (iii) RF oxygen plasma etching, and (iv) high-vacuum argon-ion sputtering. The O 1s spectra for the GZO electrodes have contributions from the stoichiometric oxide lattice, defects within the lattice, hydroxylated species, and carbonaceous impurities, with relative near-surface compositions varying with pretreatment. Solution etching procedures result in an increase of the work function and ionization potential of the GZO electrode, but yield different near surface Zn:Ga atomic ratios, which significantly influence charge transfer rates for a chemisorbed probe molecule. The near surface chemical composition is shown to be the dominant factor in controlling surface work function and significantly influences the rate of electron transfer to both solution and tethered probe molecules.

Ratcliff, E. L.; Sigdel, A. K.; Macech, M. R.; Nebesny, K.; Lee, P. A.; Ginley, D. S.; Armstrong, N. R.; Berry, J. J.

2012-06-30T23:59:59.000Z

205

The Influence of Lewis Acid/Base Chemistry on the Removal of Gallium by Volatility from Weapons-Grade Plutonium Dissolved in Molten Chlorides  

Science Conference Proceedings (OSTI)

It has been proposed that GaCl{sub 3} can be removed by direct volatilization from a Pu-Ga alloy that is dissolved in a molten chloride salt. Although pure GaCl{sub 3} is quite volatile (boiling point: 201 deg. C), the behavior of GaCl{sub 3} dissolved in chloride salts is quite different because of solution effects and is critically dependent upon the composition of the solvent salt (i.e., its Lewis acid/base character). In this technical note, the behavior of gallium in prototypical Lewis acid and Lewis base salts is contrasted. It is found that gallium volatility is suppressed in basic melts and promoted in acidic melts. These results have an important influence on the potential for simple gallium removal in molten salt systems.

Williams, David F.; Cul, Guillermo D. del [Oak Ridge National Laboratory (United States); Toth, Louis M. [Electrochemical Systems (United States); Collins, Emory D. [Oak Ridge National Laboratory (United States)

2001-12-15T23:59:59.000Z

206

Excitation wavelength dependence of water-window line emissions from boron-nitride laser-produced plasmas  

E-Print Network (OSTI)

Excitation wavelength dependence of water-window line emissions from boron-nitride laser-produced of laser excitation wavelength on water-window emission lines of laser- produced boron-nitride plasmas. Plasmas are produced by focusing 1064 nm and harmonically generated 532 and 266 nm radiation from a Nd

Harilal, S. S.

207

HIGH-EFFICIENCY NITRIDE-BASED SOLID-STATE LIGHTING  

SciTech Connect

In this second annual report we summarize the progress in the second-year period of Department of Energy contract DE-FC26-01NT41203, entitled ''High- Efficiency Nitride-Based Solid-State Lighting''. The two teams, from the University of California at Santa Barbara (Principle Investigator: Dr. Shuji Nakamura) and Rensselaer Polytechnic Institute (led by Dr. N. Narendran), are pursuing the goals of this contract from thin film growth, characterization, and packaging standpoints. The UCSB team has recently made significant progress in the development of light-emitting diodes (LEDs) with AlGaN active regions emitting in the ultraviolet (UV), resonant-cavity LEDs (RCLEDs), as well as lateral epitaxial overgrowth (LEO) techniques to obtain large-area non-polar GaN films with low average dislocation density. The Rensselaer team has benchmarked the performance of commercially available LED systems and has also conducted efforts to develop an optimized RCLED packaging scheme, including development of advanced epoxy encapsulant chemistries.

Paul T. Fini; Shuji Nakamura

2003-10-30T23:59:59.000Z

208

Radial elasticity of multi-walled boron nitride nanotubes  

Science Conference Proceedings (OSTI)

We investigated the radial mechanical properties of multi-walled boron nitride nanotubes (MW-BNNTs) using atomic force microscopy. The employed MW-BNNTs were synthesized using pressurized vapor/condenser (PVC) methods and were dispersed in aqueous solution using ultrasonication methods with the aid of ionic surfactants. Our nanomechanical measurements reveal the elastic deformational behaviors of individual BNNTs with two to four tube walls in their transverse directions. Their effective radial elastic moduli were obtained through interpreting their measured radial deformation profiles using Hertzian contact mechanics models. Our results capture the dependences of the effective radial moduli of MW-BNNTs on both the tube outer diameter and the number of tube layers. The effective radial moduli of double-walled BNNTs are found to be several-fold higher than those of single-walled BNNTs within the same diameter range. Our work contributes directly to a complete understanding of the fundamental structural and mechanical properties of BNNTs and the pursuits of their novel structural and electronics applications.

Michael W. Smith, Cheol Park, Meng Zheng, Changhong Ke ,In-Tae Bae, Kevin Jordan

2012-02-01T23:59:59.000Z

209

Synthesis of fine-grained .alpha.-silicon nitride by a combustion process  

DOE Patents (OSTI)

A combustion synthesis process for the preparation of .alpha.-silicon nitride and composites thereof is disclosed. Preparation of the .alpha.-silicon nitride comprises the steps of dry mixing silicon powder with an alkali metal azide, such as sodium azide, cold-pressing the mixture into any desired shape, or loading the mixture into a fused, quartz crucible, loading the crucible into a combustion chamber, pressurizing the chamber with nitrogen and igniting the mixture using an igniter pellet. The method for the preparation of the composites comprises dry mixing silicon powder (Si) or SiO.sub.2, with a metal or metal oxide, adding a small amount of an alkali metal azide such as sodium azide, introducing the mixture into a suitable combustion chamber, pressurizing the combustion chamber with nitrogen, igniting the mixture within the combustion chamber, and isolating the .alpha.-silicon nitride formed as a reaction product.

Holt, J. Birch (San Jose, CA); Kingman, Donald D. (Danville, CA); Bianchini, Gregory M. (Livermore, CA)

1990-01-01T23:59:59.000Z

210

Nuclear fuels technologies: Thermally induced gallium removal system (TIGRS), fiscal year 1998 research and development test plan  

SciTech Connect

This document details the research and development (R and D) activities that will be conducted in Fiscal Year 1998 (FY98) by the Thermally Induced Gallium Removal System (TIGRS) team for the Department of Energy Office of Fissile Materials Disposition. This work is a continuation and extension of experimental activities that have been conducted in support of using weapons-derived plutonium in the fabrication of mixed-oxide (MOX) nuclear fuel for reactor-based plutonium disposition. The ultimate purpose of this work is to demonstrate adequate Thermally Induced Gallium Removal with a prototypic system. This Test Plan presents more than the FY98 R and D efforts in order to frame the Task in its entirety. To achieve the TIGRS Program objectives, R and D activities during the next two years will be focused on (1) process development leading to a prototypic TIGRS design, and (2) prototypic TIGRS design and testing leading to and including a prototypic demonstration of TIGRS operation. Both the process development and system testing efforts will consist of a series of surrogate-based cold tests and plutonium-based hot tests. Some of this testing has already occurred and will continue into FY99.

Buksa, J.J.; Butt, D.P.; Chidester, K.; DeMuth, S.F.; Havrilla, G.J.; James, C.A.; Kolman, D.G.

1997-12-24T23:59:59.000Z

211

Alternative Liquid Fuel Effects on Cooled Silicon Nitride Marine Gas Turbine Airfoils  

Science Conference Proceedings (OSTI)

With prior support from the Office of Naval Research, DARPA, and U.S. Department of Energy, United Technologies is developing and engine environment testing what we believe to be the first internally cooled silicon nitride ceramic turbine vane in the United States. The vanes are being developed for the FT8, an aeroderivative stationary/marine gas turbine. The current effort resulted in further manufacturing and development and prototyping by two U.S. based gas turbine grade silicon nitride component manufacturers, preliminary development of both alumina, and YTRIA based environmental barrier coatings (EBC's) and testing or ceramic vanes with an EBC coating.

Holowczak, J.

2002-03-01T23:59:59.000Z

212

Formation of copper-indium-selenide and/or copper-indium-gallium-selenide films from indium selenide and copper selenide precursors  

DOE Patents (OSTI)

Liquid-based indium selenide and copper selenide precursors, including copper-organoselenides, particulate copper selenide suspensions, copper selenide ethylene diamine in liquid solvent, nanoparticulate indium selenide suspensions, and indium selenide ethylene diamine coordination compounds in solvent, are used to form crystalline copper-indium-selenide, and/or copper indium gallium selenide films (66) on substrates (52).

Curtis, Calvin J. (Lakewood, CO); Miedaner, Alexander (Boulder, CO); Van Hest, Maikel (Lakewood, CO); Ginley, David S. (Evergreen, CO); Nekuda, Jennifer A. (Lakewood, CO)

2011-11-15T23:59:59.000Z

213

Method of chemical vapor deposition of boron nitride using polymeric cyanoborane  

DOE Patents (OSTI)

Polymeric cyanoborane is volatilized, decomposed by thermal or microwave plasma energy, and deposited on a substrate as an amorphous film containing boron, nitrogen and carbon. Residual carbon present in the film is removed by ammonia treatment at an increased temperature, producing an adherent, essentially stoichiometric boron nitride film.

Maya, Leon (Oak Ridge, TN)

1994-01-01T23:59:59.000Z

214

Hands-On Session 6: Monolayer Boron Nitride BerkeleyGW Workshop  

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

Hands-On Session 6: Monolayer Boron Nitride Hands-On Session 6: Monolayer Boron Nitride BerkeleyGW Workshop 11/23/2013 Diana Qiu Goals: 1. Demonstrate a GW-BSE calculation for a 2D semiconductor 2. Look at the behavior of ε -1 00 (q) for a system with a truncated Coulomb interaction 3. Learn how to use BerkeleyGW's visualization tools to look at the exciton wave function Instructions: Please copy the example directory into your scratch directory >> cp -rP /project/projectdirs/m1694/BGW-2013/6-boron_nitride $SCRATCH/ 1-MF ● Please go the directory ``6-boron_nitride/1-mf/`` ● Enter each directory in numerical order and follow the instructions in the README files. Some things to note for 2D calculations: ● The system is in a periodic supercell. Though we will not do so in this calculation, you should always converge the k-grid sampling and amount of vacuum between

215

Silicon-doped boron nitride coated fibers in silicon melt infiltrated composites  

SciTech Connect

A fiber-reinforced silicon-silicon carbide matrix composite having improved oxidation resistance at high temperatures in dry or water-containing environments is produced. The invention also provides a method for protecting the reinforcing fibers in the silicon-silicon carbide matrix composites by coating the fibers with a silicon-doped boron nitride coating.

Corman, Gregory Scot (Ballston Lake, NY); Luthra, Krishan Lal (Schenectady, NY)

2002-01-01T23:59:59.000Z

216

Silicon-doped boron nitride coated fibers in silicon melt infiltrated composites  

SciTech Connect

A fiber-reinforced silicon--silicon carbide matrix composite having improved oxidation resistance at high temperatures in dry or water-containing environments is produced. The invention also provides a method for protecting the reinforcing fibers in the silicon--silicon carbide matrix composites by coating the fibers with a silicon-doped boron nitride coating.

Corman, Gregory Scot (Ballston Lake, NY); Luthra, Krishan Lal (Schenectady, NY)

1999-01-01T23:59:59.000Z

217

Silicon-doped boron nitride coated fibers in silicon melt infiltrated composites  

SciTech Connect

A fiber-reinforced silicon-silicon carbide matrix composite having improved oxidation resistance at high temperatures in dry or water-containing environments is produced. The invention also provides a method for protecting the reinforcing fibers in the silicon-silicon carbide matrix composites by coating the fibers with a silicon-doped boron nitride coating.

Corman, G.S.; Luthra, K.L.

1999-09-14T23:59:59.000Z

218

Bonding in hard and elastic amorphous carbon nitride films investigated H NMR spectroscopy  

E-Print Network (OSTI)

Bonding in hard and elastic amorphous carbon nitride films investigated using 15 N, 13 C, and 1 H Received 14 February 2003; published 5 November 2003 The nitrogen bonding in hard and elastic amorphous substrates at 300 °C. Nanoindentation tests revealed an elastic recovery of 80%, a hardness of 5 GPa

Reilly, Anne

219

Sintered Reaction Bonded Silicon Parts by Microwave Nitridation Combined with Gas-Pressure Sintering  

DOE Green Energy (OSTI)

The cooperative project was a joint development program between Ceradyne and Oak Ridge National Laboratory through Lockheed Martin Energy Research (LMER). Cooperative work was of benefit to both parties. ORNL was able to assess the effect of the microwave nitridation process coupled with gas-pressure sintering for fabrication of parts for advanced diesel engines. Ceradyne gained access to gelcasting expertise and microwave facilities and experience for the nitridation of SRBSN materials. The broad objective of the CRADA between Ceradyne and OIWL was to (1) examine the applicability of the gelcasting technology to fabricate parts from SRBSN, and (2) to assess the effect of the microwave nitridation of silicon process coupled with gas-pressure sintering for fabrication of parts for advanced diesel engines. The following conclusions can be made from the work performed under the CRADA: (1) Gelcasting is a viable method to fabricate SRBSN parts using Ceradyne Si mixtures. However, the technique requires further development prior to being put into commercial use. (2) Microwave heating can be utilized to nitride multiple SRBSN parts. Scale-up of the process to fabricate several kilograms of material (up to 6 kg) per furnace run was demonstrated.

Kiggans, J.O.; Mikijelj, B.; Tiegs, T.N.

1999-01-01T23:59:59.000Z

220

Evaluation and silicon nitride internal combustion engine components. Final report, Phase I  

DOE Green Energy (OSTI)

The feasibility of silicon nitride (Si{sub 3}N{sub 4}) use in internal combustion engines was studied by testing three different components for wear resistance and lower reciprocating mass. The information obtained from these preliminary spin rig and engine tests indicates several design changes are necessary to survive high-stress engine applications. The three silicon nitride components tested were valve spring retainers, tappet rollers, and fuel pump push rod ends. Garrett Ceramic Components` gas-pressure sinterable Si{sub 3}N{sub 4} (GS-44) was used to fabricate the above components. Components were final machined from densified blanks that had been green formed by isostatic pressing of GS-44 granules. Spin rig testing of the valve spring retainers indicated that these Si{sub 3}N{sub 4} components could survive at high RPM levels (9,500) when teamed with silicon nitride valves and lower spring tension than standard titanium components. Silicon nitride tappet rollers showed no wear on roller O.D. or I.D. surfaces, steel axles and lifters; however, due to the uncrowned design of these particular rollers the cam lobes indicated wear after spin rig testing. Fuel pump push rod ends were successful at reducing wear on the cam lobe and rod end when tested on spin rigs and in real-world race applications.

Voldrich, W. [Allied-Signal Aerospace Co., Torrance, CA (United States). Garrett Ceramic Components Div.

1992-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "gallium nitride ingan" 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

Compatibility/Stability Issues in the Use of Nitride Kernels in LWR TRISO Fuel  

SciTech Connect

The stability of the SiC layer in the presence of free nitrogen will be dependent upon the operating temperatures and resulting nitrogen pressures whether it is at High Temperature Gas-Cooled Reactor (HTGR) temperatures of 1000-1400 C (coolant design dependent) or LWR temperatures that range from 500-700 C. Although nitrogen released in fissioning will form fission product nitrides, there will remain an overpressure of nitrogen of some magnitude. The nitrogen can be speculated to transport through the inner pyrolytic carbon layer and contact the SiC layer. The SiC layer may be envisioned to fail due to resulting nitridation at the elevated temperatures. However, it is believed that these issues are particularly avoided in the LWR application. Lower temperatures will result in significantly lower nitrogen pressures. Lower temperatures will also substantially reduce nitrogen diffusion rates through the layers and nitriding kinetics. Kinetics calculations were performed using an expression for nitriding silicon. In order to further address these concerns, experiments were run with surrogate fuel particles under simulated operating conditions to determine the resulting phase formation at 700 and 1400 C.

Armstrong, Beth L [ORNL; Besmann, Theodore M [ORNL

2012-02-01T23:59:59.000Z

222

Method of chemical vapor deposition of boron nitride using polymeric cyanoborane  

DOE Patents (OSTI)

Polymeric cyanoborane is volatilized, decomposed by thermal or microwave plasma energy, and deposited on a substrate as an amorphous film containing boron, nitrogen and carbon. Residual carbon present in the film is removed by ammonia treatment at an increased temperature, producing an adherent, essentially stoichiometric boron nitride film. 11 figs.

Maya, L.

1994-06-14T23:59:59.000Z

223

NIST Manuscript Publication Search  

Science Conference Proceedings (OSTI)

... Abstract: Although the efficiency of the Gallium Nitride (GaN) Light Emitting-Diode (LED) has improved in the past decade, a great opportunity ...

2013-12-19T23:59:59.000Z

224

Development of a Bulk GaN Growth Technique for Low Defect Density...  

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

Enabling Next-Generation Power Electronics: Electrochemical Solution Growth (ESG) Technique for Bulk Gallium Nitride Substrates Karen Waldrip Dept. 2546, Advanced Power Sources R&D...

225

at-meeting technical program in .pdf format  

Science Conference Proceedings (OSTI)

Jun 24, 1998 ... trical Engr., Walter Scott Engr. Center, Lincoln, NE 68588-0511 USA; ...... Radiative Efficiency of High Quality Gallium Nitride Thin Films: Peter.

226

NETL: NEPA Categorical Exclusions - January 2010 to March 2010  

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

EEProject Management Center Y 352010 Advanced Epi Tools for Gallium Nitride Light Emitting Diode Devices Applied Materials, Inc. Santa Clara, CA EEBETD Y 352010 Red Birch...

227

Solid-State Lighting: 2012 Solid-State Lighting Manufacturing...  

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

Frank Cerio, Veeco Instruments Advanced Epi Tools for Gallium Nitride Light Emitting Diode Devices Vivek Agrawal, Applied Materials Driving Down HB-LED Costs:...

228

Solid-State Lighting Issue 28: Scientific Literature (Mid May...  

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

National University of Kaohsiung (Taiwan): "Wavelength shift of gallium nitride light emitting diode with p-down structure." W.H. Lan, IEEE Transactions on Electron Devices,...

229

Visit the National Academies Press online, the authoritative ...  

Science Conference Proceedings (OSTI)

... of the US electricity generation, and oil prices should not ... swings and a poor heating, ventilating, and air ... to gallium nitride growth is “home-built,” and ...

2012-09-27T23:59:59.000Z

230

Categorical Exclusion Determinations: American Recovery and Reinvestme...  

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

Exclusion Determination Transphorm, Inc. -High Performance Gallium Nitride High Electron Mobility Transistor Modules for Agile Power Electronics CX(s) Applied: B3.6 Date:...

231

Page not found | Department of Energy  

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

Exclusion Determination Transphorm, Inc. -High Performance Gallium Nitride High Electron Mobility Transistor Modules for Agile Power Electronics CX(s) Applied: B3.6 Date:...

232

Chemical thermodynamics of nuclear materials. IX. High temperature heat capacity of plutonium-3. 2 at. % gallium alloy  

Science Conference Proceedings (OSTI)

The heat capacity of delta-stabilized plutonium (Pu - 3.2 at. % Ga) has been determined from 330 to 700/sup 0/K by an adiabatic calorimeter. The heat capacity for this alloy may be expressed by: Cp (Pu-3.2 at. % Ga)/(J K/sup -1/ mol/sup -1/) = 39.249 - 0.0264 (T/K) + 3.595 x 10/sup 5/ (T/K)/sup 2/ - 2.506 x 10/sup 5/ (K/T)/sup 2/. It was found that a large contribution to the heat capacity is due to the electronic heat capacity. The thermal functions for this plutonium-gallium alloy are calculated to 700/sup 0/K.

Adams, R.O.; Oetting, F.L.

1982-01-01T23:59:59.000Z

233

An experiment to test the viability of a gallium-arsenide cathode in a SRF electron gun  

SciTech Connect

Strained gallium arsenide cathodes are used in electron guns for the production of polarized electrons. In order to have a sufficient quantum efficiency lifetime of the cathode the vacuum in the gun must be 10{sup -11} Torr or better, so that the cathode is not destroyed by ion back bombardment or through contamination with residual gases. All successful polarized guns are DC guns, because such vacuum levels can not be obtained in normal conducting RF guns. A superconductive RF gun may provide a sufficient vacuum level due to cryo-pumping of the cavity walls. We report on the progress of our experiment to test such a gun with normal GaAs-Cs crystals.

Kewisch,J.; Ben-Zvi, I.; Rao, T.; Burrill, A.; Pate, D.; Wu, Q.; Todd, R.; Wang, E.; Bluem, H.; Holmes, D.; Schultheiss, T.

2009-05-04T23:59:59.000Z

234

Comparison of Cavitation-Erosion Resistance of Carburized and Carburized-Plus-Nitrided 316LN Stainless Steel in Mercury  

SciTech Connect

Annealed type 316LN stainless steel in the (1) carburized and the (2) carburized plus nitrided conditions was evaluated for cavitation-erosion resistance in ambient temperature mercury using a vibratory horn method. The results indicated that, relative to the specimens receiving only the carburizing treatment, the specimens that received both surface treatments exhibited substantially greater weight loss, general thinning, and profile development as a function of sonication time - with all observed degradation limited to the nitrided layer. Further, the nitride layer was observed to be susceptible to extensive cracking (occasionally leading to spallation), but the cracking was never observed to penetrate into the carburized layer. These screening test results suggest there is no improvement in cavitation-erosion resistance associated with augmentation of the carburizing treatment with plasma nitriding.

Pawel, Steven J [ORNL

2007-05-01T23:59:59.000Z

235

Aluminum nitride transitional layer for reducing dislocation density and cracking of AlGaN epitaxial films  

DOE Patents (OSTI)

A denticulated Group III nitride structure that is useful for growing Al.sub.xGa.sub.1-xN to greater thicknesses without cracking and with a greatly reduced threading dislocation (TD) density.

Allerman, Andrew A.; Crawford, Mary H.; Lee, Stephen R.

2013-01-08T23:59:59.000Z

236

High density hexagonal boron nitride prepared by hot isostatic pressing in refractory metal containers  

DOE Patents (OSTI)

Boron nitride powder with less than or equal to the oxygen content of starting powder (down to 0.5% or less) is hot isostatically pressed in a refractory metal container to produce hexagonal boron nitride with a bulk density greater than 2.0 g/cc. The refractory metal container is formed of tantalum, niobium, tungsten, molybdenum or alloys thereof in the form of a cansister or alternatively plasma sprayed or chemical vapor deposited onto a powder compact. Hot isostatic pressing at 1800{degrees}C and 30 KSI (206.8 MPa) argon pressure for four hours produces a bulk density of 2.21 g/cc. Complex shapes can be made.

Hoenig, C.L.

1990-12-31T23:59:59.000Z

237

Superstructure of self-aligned hexagonal GaN nanorods formed on nitrided Si(111) surface  

SciTech Connect

We present here the spontaneous formation of catalyst-free, self-aligned crystalline (wurtzite) nanorods on Si(111) surfaces modified by surface nitridation. Nanorods grown by molecular beam epitaxy on bare Si(111) and non-stoichiometric silicon nitride interface are found to be single crystalline but disoriented. Those grown on single crystalline Si{sub 3}N{sub 4} intermediate layer are highly dense c-oriented hexagonal shaped nanorods. The morphology and the self-assembly of the nanorods shows an ordered epitaxial hexagonal superstructure, suggesting that they are nucleated at screw dislocations at the interface and grow spirally in the c-direction. The aligned nanorod assembly shows high-quality structural and optical emission properties.

Kumar, Praveen; Tuteja, Mohit; Kesaria, Manoj; Waghmare, U. V.; Shivaprasad, S. M. [Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560 064 (India)

2012-09-24T23:59:59.000Z

238

Understanding the Potential and Limitations of Dilute Nitride Alloys for Solar Cells  

DOE Green Energy (OSTI)

Dilute nitride alloys provide a powerful tool for engineering the band gap and lattice constant of III-V alloys. However, nitrogen degrades the performance of GaAs solar cells. This project seeks to understand and demonstrate the limits of performance of GaInNAs alloys by (a) correlating deep-level transient spectroscopy (DLTS) data with device performance and (b) using molecular beam epitaxy (MBE) to reduce background impurity concentrations.

Kurtz, S.; Ptak, A.; Johnston, S.; Kramer, C.; Young, M.; Friedman, D.; Geisz, J.; McMahon, W.; Kibbler, A.; Olson, J.; Crandall, R.; Branz, H.

2005-11-01T23:59:59.000Z

239

Behavior of molybdenum nitrides as materials for electrochemical capacitors: Comparison with ruthenium oxide  

Science Conference Proceedings (OSTI)

Ruthenium oxide (RuO{sub 2}), formed as a thin film on a Ru or Ti metal substrate, exhibits a large specific (cm{sup {minus}2}) and almost constant, electrochemical capacitance over a 1.35 V range in aqueous H{sub 2}SO{sub 4}. This behavior has led to its investigation and use as a material for fabrication of supercapacitor devices. However, its cost has encouraged search for other materials exhibiting similar behavior. Work reported in the present paper evaluates two nitrides of Mo, Mo{sub 2}N and MoN, as substitutes for RuO{sub 2}. It is shown that very similar capacitance behavior to that of RuO{sub 2} films arises, e.g., in cyclic voltammetry and dc charging curves; in the former, almost mirror-image anodic and cathodic current-response profiles, characteristic of a capacitor, arise. However, the nitride materials have a substantially smaller voltage operating range of only some 0.7 V due to electrochemical decomposition above ca. 0.7 V vs. RHE. This limits their usefulness as a substitute for RuO{sub 2}. Of interest is that the nitride films exhibit potential-decay and potential-recovery on open circuit after respective charge and forced discharge. The decay and recovery processes are logarithmic in time, indicating the role of internal faradaic charge redistribution processes.

Liu, T.C.; Pell, W.G.; Conway, B.E. [Univ. of Ottawa, Ontario (Canada). Dept. of Chemistry; Roberson, S.L. [North Carolina State Univ., Raleigh, NC (United States). Dept. of Materials Science and Engineering

1998-06-01T23:59:59.000Z

240

Analytical and experimental evaluation of joining silicon carbide to silicon carbide and silicon nitride to silicon nitride for advanced heat engine applications Phase 2. Final report  

DOE Green Energy (OSTI)

The purpose of joining, Phase 2 was to develop joining technologies for HIP`ed Si{sub 3}N{sub 4} with 4wt% Y{sub 2}O{sub 3} (NCX-5101) and for a siliconized SiC (NT230) for various geometries including: butt joins, curved joins and shaft to disk joins. In addition, more extensive mechanical characterization of silicon nitride joins to enhance the predictive capabilities of the analytical/numerical models for structural components in advanced heat engines was provided. Mechanical evaluation were performed by: flexure strength at 22 C and 1,370 C, stress rupture at 1,370 C, high temperature creep, 22 C tensile testing and spin tests. While the silicon nitride joins were produced with sufficient integrity for many applications, the lower join strength would limit its use in the more severe structural applications. Thus, the silicon carbide join quality was deemed unsatisfactory to advance to more complex, curved geometries. The silicon carbide joining methods covered within this contract, although not entirely successful, have emphasized the need to focus future efforts upon ways to obtain a homogeneous, well sintered parent/join interface prior to siliconization. In conclusion, the improved definition of the silicon carbide joining problem obtained by efforts during this contract have provided avenues for future work that could successfully obtain heat engine quality joins.

Sundberg, G.J.; Vartabedian, A.M.; Wade, J.A.; White, C.S. [Norton Co., Northboro, MA (United States). Advanced Ceramics Div.

1994-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "gallium nitride ingan" 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

Power mixture and green body for producing silicon nitride base articles of high fracture toughness and strength  

DOE Patents (OSTI)

A powder mixture and a green body for producing a silicon nitride-based article of improved fracture toughness and strength are disclosed. The powder mixture includes (a) a bimodal silicon nitride powder blend consisting essentially of about 10-30% by weight of a first silicon nitride powder of an average particle size of about 0.2 [mu]m and a surface area of about 8-12m[sup 2]g, and about 70-90% by weight of a second silicon nitride powder of an average particle size of about 0.4-0.6 [mu]m and a surface area of about 2-4 m[sup 2]/g, (b) about 10-50 percent by volume, based on the volume of the densified article, of refractory whiskers or fibers having an aspect ratio of about 3-150 and having an equivalent diameter selected to produce in the densified article an equivalent diameter ratio of the whiskers or fibers to grains of silicon nitride of greater than 1.0, and (c) an effective amount of a suitable oxide densification aid. The green body is formed from the powder mixture, an effective amount of a suitable oxide densification aid, and an effective amount of a suitable organic binder. No Drawings

Huckabee, M.L.; Buljan, S.T.; Neil, J.T.

1991-09-17T23:59:59.000Z

242

Electrical Bias as an Alternate Method for Reproducible Measurement of Copper Indium Gallium Diselenide (CIGS) Photovoltaic Modules: Preprint  

DOE Green Energy (OSTI)

Light-to-dark metastable changes in thin-film photovoltaic (PV) modules can introduce uncertainty when measuring module performance on indoor flash testing equipment. This study describes a method to stabilize module performance through forward-bias current injection rather than light exposure. Measurements of five pairs of thin-film copper indium gallium diselenide (CIGS) PV modules indicate that forward-bias exposure maintained the PV modules at a stable condition (within 1%) while the unbiased modules degraded in performance by up to 12%. It was additionally found that modules exposed to forward bias exhibited stable performance within about 3% of their long-term outdoor exposed performance. This carrier-injection method provides a way to reduce uncertainty arising from fast transients in thin-film module performance between the time a module is removed from light exposure and when it is measured indoors, effectively simulating continuous light exposure by injecting minority carriers that behave much as photocarriers do. This investigation also provides insight into the initial light-induced transients of thin-film modules upon outdoor deployment.

Deline, C.; Stokes, A.; Silverman, T. J.; Rummel, S.; Jordan, D.; Kurtz, S.

2012-08-01T23:59:59.000Z

243

Derived reference doses for three compounds used in the photovoltaics industry: Copper indium diselenide, copper gallium diselenide, and cadmium telluride  

DOE Green Energy (OSTI)

Polycrystalline thin-film photovoltaic modules made from copper indium diselenide (CIS), copper gallium diselenide (CGS), and cadmium telluride (CdTe) arc nearing commercial development. A wide range of issues are being examined as these materials move from the laboratory to large-scale production facilities to ensure their commercial success. Issues of traditional interest include module efficiency, stability and cost. More recently, there is increased focus given to environmental, health and safety issues surrounding the commercialization of these same devices. An examination of the toxicological properties of these materials, and their chemical parents is fundamental to this discussion. Chemicals that can present large hazards to human health or the environment are regulated often more strictly than those that are less hazardous. Stricter control over how these materials are handled and disposed can increase the costs associated with the production and use of these modules dramatically. Similarly, public perception can be strongly influenced by the inherent biological hazard that these materials possess. Thus, this report: presents a brief background tutorial on how toxicological data are developed and used; overviews the toxicological data available for CIS, CGS and CdTe; develops ``reference doses`` for each of these compounds; compares the reference doses for these compounds with those of their parents; discusses the implications of these findings to photovoltaics industry.

Moskowitz, P.D.; Bernholc, N.; DePhillips, M.P.; Viren, J.

1995-07-06T23:59:59.000Z

244

Low energy solar neutrino experiments: The Soviet American Gallium Experiment (SAGE). Final report, August 12, 1988--October 31, 1994  

SciTech Connect

Two {sup 71}Ga experiments are currently in operation. The first is the 60 ton Soviet American Gallium Experiment (SAGE) at Baksan, which has recently reported a signal level of 73+18/{minus}16(stat)+5/{minus}7(syst) SNU; the second is the 30 ton GALLEX experiment at Gran Sasso, which sees 87{+-}14{+-}7 SNU. Both results are consistent, and both suggest a neutrino flux level low compared to the total expected from standard solar model calculations. It is not possible, however, to make a case for flux levels lower than the p-p prediction. Assuming the experiments are correct (Neutrino source calibrations are planned for both SAGE and GALLEX in the near future.), it is not at all clear yet whether the answer lies with the neutrino physics, solar physics, or a combination of both. Nevertheless, though solar model effects cannot be ruled out, if the Homestake and Kamiokande results are taken at face value, then these two experiments alone imply that neutrino oscillations or some similar particle physics result must be present to some degree. This report reviews the SAGE experiment and recent results. Non-radiochemical experiments are also discussed, with an emphasis on the Kamiokande water Cerenkov results.

NONE

1995-04-01T23:59:59.000Z

245

The effect of low levels of dopants upon the formation and properties of beta-phase molybdenum nitride  

Science Conference Proceedings (OSTI)

The addition of 1 wt% Pd, Au, Ni and Cu dopants has been demonstrated to strongly alter the morphology of beta-phase molybdenum nitride prepared by treatment of MoO{sub 3} with a 3/1 H{sub 2}/N{sub 2} mixture at 750 deg. C. Furthermore, the addition of Pd significantly enhances the surface area and the formation of the nitride phase. It is proposed that the facile formation of molybdenum bronzes in this system is important in this respect. The dopants have also been observed to modify the denitridation characteristics of the beta-phase, with an overall reduction of the proportion of NH{sub 3} formed upon using a 3/1 H{sub 2}/Ar mixture with respect to the undoped sample. - Graphical abstract: Low levels of Pd, Au, Ni and Cu dopant have significant effects upon the morphology, formation and dentitridation characteristics of beta-phase molybdenum nitride.

Cairns, A.G.; Gallagher, J.G. [WestCHEM, Department of Chemistry, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Hargreaves, J.S.J., E-mail: justinh@chem.gla.ac.u [WestCHEM, Department of Chemistry, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Mckay, D. [WestCHEM, Department of Chemistry, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Rico, J.L., E-mail: jlrico@umich.m [Laboratorio de Catalisis, Facultad de Ingenieria Quimica, Universidad Michoacana, Edificio E, CU, Morelia Mich, C.P. 58060 (Mexico); Wilson, K. [WestCHEM, Department of Chemistry, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ (United Kingdom)

2010-03-15T23:59:59.000Z

246

LATE NEWS: KK3, Non-Catalytic Synthesis of GaN Nanostructures ...  

Science Conference Proceedings (OSTI)

We have observed the synthesis of gallium nitride (GaN) nanopowders on boron ... as 400°C. The synthesis process is based on the reaction between gallium atoms from the decomposition of gallium acetylacetonate and ammonia gas molecules. ... the crystal structure and growth mechanism of the grown nanostructures.

247

Very long single- and few-walled boron nitride nanotubes via the pressurized vapor/condenser method  

Science Conference Proceedings (OSTI)

Boron nitride nanotubes (BNNTs) are desired for their exceptional mechanical, electronic, thermal, structural, textural, optical, and quantum properties. A new method for producing long, small-diameter, single- and few-walled, boron nitride nanotubes (BNNTs) in macroscopic quantities is reported. The pressurized vapor/condenser (PVC) method produces, without catalysts, highly crystalline, very long, small-diameter, BNNTs. Palm-sized, cotton-like masses of BNNT raw material were grown by this technique and spun directly into centimeters-long yarn. Nanotube lengths were observed to be 100 times that of those grown by the most closely related method. Self-assembly and growth models for these long BNNTs are discussed.

Michael W. Smith, Kevin Jordan, Cheol Park, Jae-Woo Kim, Peter Lillehei, Roy Crooks, Joycelyn Harrison

2009-11-01T23:59:59.000Z

248

Influence of process parameters on properties of reactively sputtered tungsten nitride thin films  

SciTech Connect

Tungsten nitride (WN{sub x}) thin films were produced by reactive dc magnetron sputtering of tungsten in an Ar-N{sub 2} gas mixture. The influence of the deposition power on the properties of tungsten nitride has been analyzed and compared with that induced by nitrogen content variation in the sputtering gas. A combined analysis of structural, electrical and optical properties on thin WN{sub x} films obtained at different deposition conditions has been performed. It was found that at an N{sub 2} content of 14% a single phase structure of W{sub 2}N films was formed with the highest crystalline content. This sputtering gas composition was subsequently used for fabricating films at different deposition powers. Optical analysis showed that increasing the deposition power created tungsten nitride films with a more metallic character, which is confirmed with resistivity measurements. At low sputtering powers the resulting films were crystalline whereas, with an increase of power, an amorphous phase was also present. The incorporation of an excess of nitrogen atoms resulted in an expansion of the W{sub 2}N lattice and this effect was more pronounced at low deposition powers. Infrared analysis revealed that in WN{sub x} films deposited at low power, chemisorbed N{sub 2} molecules did not behave as ligands whereas at high deposition power they clearly appeared as ligands around metallic tungsten. In this study, the influence of the most meaningful deposition parameters on the phase transformation reaction path was established and deposition conditions suitable for producing thermally stable and highly crystalline W{sub 2}N films were found.

Addonizio, Maria L.; Castaldo, Anna; Antonaia, Alessandro; Gambale, Emilia; Iemmo, Laura [ENEA, Portici Research Centre, Piazzale E. Fermi 1, I-80055, Portici (Italy)

2012-05-15T23:59:59.000Z

249

III-antimonide/nitride based semiconductors for optoelectronic materials and device studies : LDRD 26518 final report.  

DOE Green Energy (OSTI)

The goal of this LDRD was to investigate III-antimonide/nitride based materials for unique semiconductor properties and applications. Previous to this study, lack of basic information concerning these alloys restricted their use in semiconductor devices. Long wavelength emission on GaAs substrates is of critical importance to telecommunication applications for cost reduction and integration into microsystems. Currently InGaAsN, on a GaAs substrate, is being commercially pursued for the important 1.3 micrometer dispersion minima of silica-glass optical fiber; due, in large part, to previous research at Sandia National Laboratories. However, InGaAsN has not shown great promise for 1.55 micrometer emission which is the low-loss window of single mode optical fiber used in transatlantic fiber. Other important applications for the antimonide/nitride based materials include the base junction of an HBT to reduce the operating voltage which is important for wireless communication links, and for improving the efficiency of a multijunction solar cell. We have undertaken the first comprehensive theoretical, experimental and device study of this material with promising results. Theoretical modeling has identified GaAsSbN to be a similar or potentially superior candidate to InGaAsN for long wavelength emission on GaAs. We have confirmed these predictions by producing emission out to 1.66 micrometers and have achieved edge emitting and VCSEL electroluminescence at 1.3 micrometers. We have also done the first study of the transport properties of this material including mobility, electron/hole mass, and exciton reduced mass. This study has increased the understanding of the III-antimonide/nitride materials enough to warrant consideration for all of the target device applications.

Kurtz, Steven Ross; Hargett, Terry W.; Serkland, Darwin Keith; Waldrip, Karen Elizabeth; Modine, Normand Arthur; Klem, John Frederick; Jones, Eric Daniel; Cich, Michael Joseph; Allerman, Andrew Alan; Peake, Gregory Merwin

2003-12-01T23:59:59.000Z

250

Annealing effects in hydrogenated silicon nitride films during high energy ion beam irradiation  

SciTech Connect

The annealing effects during energy recoil detection (ERD) analysis on the structure of hydrogenated silicon nitride film have been investigated by using fourier transform infrared (FTIR) spectroscopy. Hydrogenated silicon nitride films were prepared by plasma enhanced chemical vapor deposition with various substrate temperatures. A 2.5 MeV {sup 4}He{sup ++} ion beam was irradiated onto the film in a vacuum chamber at room temperature. The ERD signal was measured after various ion doses in order to determine the loss of hydrogen counts induced by the ion beam. The IR absorption spectrum was obtained in order to follow the film structural change which occurred due to the ion beam. The films deposited at 200 and 300 C show a significant decrease in the ERD count with increasing ion beam dose, while the film deposited at 400 C, shows no significant changes. The IR absorption peak position for Si-N stretching (830 cm{sup {minus}1}) shifted to smaller wave numbers after ion beam irradiation, while the Si-H stretching (2,160 cm{sup {minus}1}) shifted to the opposite direction. The peak position for N-H (3,360 cm{sup {minus}1}) shows no noticeable changes. Normalized peak area for the Si-N stretching increased after ion beam irradiation. The Si-H peak area decreased slightly. The N-H peak area decreased significantly. A recombination mechanism of the N and H radicals with excess Si radical coming from Si-Si bonds in Si-rich silicon nitride films has been suggested to explain the IR absorption spectral changes which have occurred due to ion beam irradiation.

Lee, J.W. [ETRI, Taejon (Korea, Republic of)]|[KAIST, Taejon (Korea, Republic of); Lee, S.H.; Yoo, H.J. [ETRI, Taejon (Korea, Republic of); Jhon, M.S.; Ryoo, R. [KAIST, Taejon (Korea, Republic of)

1995-09-01T23:59:59.000Z

251

The development of a porous silicon nitride crossflow filter; Final report, September 1988--September 1992  

Science Conference Proceedings (OSTI)

This report summarizes the work performed in developing a permeable form of silicon nitride for application to ceramic crossflow filters for use in advanced coal-fired electric power plants. The program was sponsored by the Department of Energy Morgantown Energy Technology Center and consisted of a design analysis and material development phase and a filter manufacture and demonstration phase. The crossflow filter design and operating requirements were defined. A filter design meeting the requirements was developed and thermal and stress analyses were performed. Material development efforts focused initially on reaction-bonded silicon nitride material. This approach was not successful, and the materials effort was refocused on the development of a permeable form of sintered silicon nitride (SSN). This effort was successful. The SSN material was used for the second phase of the program, filter manufacture and evaluation. Four half-scale SAN filter modules were fabricated. Three of the modules were qualified for filter performance tests. Tests were performed on two of the three qualified modules in the High-Temperature, High-Pressure facility at the Westinghouse Science and Technology Center. The first module failed on test when it expanded into the clamping device, causing dust leakage through the filter. The second module performed well for a cumulative 150-hr test. It displayed excellent filtration capability during the test. The blowback pulse cleaning was highly effective, and the module apparently withstood the stresses induced by the periodic pulse cleaning. Testing of the module resumed, and when the flow of combustion gas through the filter was doubled, cracks developed and the test was concluded.

NONE

1992-09-01T23:59:59.000Z

252

Reduction in interface state density of Al{sub 2}O{sub 3}/InGaAs metal-oxide-semiconductor interfaces by InGaAs surface nitridation  

Science Conference Proceedings (OSTI)

We report the decrease in interface trap density (D{sub it}) in Al{sub 2}O{sub 3}/InGaAs metal-oxide-semiconductor (MOS) capacitors by using electron cyclotron resonance plasma nitridation of the InGaAs surfaces. The impact of the nitridation process on the MOS interface properties is quantitatively examined. The plasma nitridation process is observed to form a nitrided layer at the InGaAs surface. The nitridation using microwave power (P{sub microwave}) of 250 W and nitridation time (t{sub nitridation}) of 420 s can form Al{sub 2}O{sub 3}/InGaAs MOS interfaces with a minimum D{sub it} value of 2.0 Multiplication-Sign 10{sup 11} cm{sup -2} eV{sup -1}. On the other hand, the nitridation process parameters such as P{sub microwave} and t{sub nitridation} are found to strongly alter D{sub it} (both decrease and increase are observed) and capacitance equivalent thickness (CET). It is found that the nitridation with higher P{sub microwave} and shorter t{sub nitridation} can reduce D{sub it} with less CET increase. Also, it is observed that as t{sub nitridation} increases, D{sub it} decreases first and increases later. It is revealed from XPS analyses that minimum D{sub it} can be determined by the balance between the saturation of nitridation and the progress of oxidation. As a result, it is found that the superior MOS interface formed by the nitridation is attributable to the existence of oxide-less InGaN/InGaAs interfaces.

Hoshii, Takuya; Lee, Sunghoon; Suzuki, Rena; Taoka, Noriyuki; Yokoyama, Masafumi; Takenaka, Mitsuru; Takagi, Shinichi [Department of Electrical Engineering and Information Systems, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Yamada, Hishashi; Hata, Masahiko [Sumitomo Chemical Co. Ltd., 6 Kitahara, Tsukuba, Ibaraki 300-3294 (Japan); Yasuda, Tetsuji [National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan)

2012-10-01T23:59:59.000Z

253

Strength and fatigue of NT551 silicon nitride and NT551 diesel exhaust valves  

DOE Green Energy (OSTI)

The content of this report is excerpted from Mark Andrew's Ph.D. Thesis (Andrews, 1999), which was funded by a DOE/OTT High Temperature Materials Laboratory Graduate Fellowship. It involves the characterization of NT551 and valves fabricated with it. The motivations behind using silicon nitride (Si{sub 3}N{sub 4}) as an exhaust valve for a diesel engine are presented in this section. There are several economic factors that have encouraged the design and implementation of ceramic components for internal combustion (IC) engines. The reasons for selecting the diesel engine valve for this are also presented.

Andrews, M.J.; Werezczak, A.A.; Kirkland, T.P.; Breder, K.

2000-02-01T23:59:59.000Z

254

Rf-plasma synthesis of nanosize silicon carbide and nitride. Final report  

DOE Green Energy (OSTI)

A pulsed rf plasma technique is capable of generating ceramic particles of 10 manometer dimension. Experiments using silane/ammonia and trimethylchlorosilane/hydrogen gas mixtures show that both silicon nitride and silicon carbide powders can be synthesized with control of the average particle diameter from 7 to 200 nm. Large size dispersion and much agglomeration appear characteristic of the method, in contrast to results reported by another research group. The as produced powders have a high hydrogen content and are air and moisture sensitive. Post-plasma treatment in a controlled atmosphere at elevated temperature (800{degrees}C) eliminates the hydrogen and stabilizes the powder with respect to oxidation or hydrolysis.

Buss, R.J.

1997-02-01T23:59:59.000Z

255

“Structural Transformations in Ceramics: Perovskite-like Oxides and Group III, IV, and V Nitrides  

SciTech Connect

1 Overview of Results and their Significance Ceramic perovskite-like oxides with the general formula (A. A0. ...)(B. B0. ...)O3and titanium-based oxides are of great technological interest because of their large piezoelectric and dielectric response characteristics.[1] In doped and nanoengineered forms, titantium dioxide finds increasing application as an organic and hydrolytic photocatalyst. The binary main-group-metal nitride compounds have undergone recent advancements of in-situ heating technology in diamond anvil cells leading to a burst of experimental and theoretical interest. In our DOE proposal, we discussed our unique theoretical approach which applies ab initio electronic calculations in conjunction with systematic group-theoretical analysis of lattice distortions to study two representative phase transitions in ceramic materials: (1) displacive phase transitions in primarily titanium-based perovskite-like oxide ceramics, and (2) reconstructive phase transitions in main-group nitride ceramics. A sub area which we have explored in depth is doped titanium dioxide electrical/optical properties.

James P. Lewis (PI, former Co-PI), Dorian M. Hatch (Co-PI, former PI), and Harold T. Stokes (Co-PI)

2006-12-31T23:59:59.000Z

256

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

SciTech Connect

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

Chambers, Scott A.

2006-10-01T23:59:59.000Z

257

Diffusion Barrier Properties of Nitride-Based Coatings on Fuel Cladding  

SciTech Connect

In this work titanium nitride (TiN) and zirconium nitride (ZrN) coatings are proposed as diffusion barriers between stainless steel nuclear fuel cladding and lanthanide fission products. TiN and ZrN have been coated as barrier materials between pure Fe and Ce, i.e. diffusion couples of Fe/TiN/Ce and Fe/ZrN/Ce, annealed up to a temperature of 600 degrees C, and compared to the diffusion behavior of uncoated Fe/Ce. Backscattered electron images and electron dispersive X-ray spectroscopy measurements confirm that, with a 500 nm TiN or ZrN layer, no obvious diffusion is observed between Fe and Ce. Basic diffusion characteristics of the Fe/Ce couple have also been measured and compared with the TiN and ZrN coated ones. The results strongly advocate that TiN and ZrN coatings provide reliable diffusion barrier characteristics against Ce and possibly other lanthanide fission products.

Fauzia Khatkhatay; Jie Jian; Liang Jiao; Qing Su; Jian Gan; James I. Cole; Haiyan Wang

2013-12-01T23:59:59.000Z

258

Power mixture and green body for producing silicon nitride base & articles of high fracture toughness and strength  

DOE Patents (OSTI)

A powder mixture and a green body for producing a silicon nitride-based article of improved fracture toughness and strength. The powder mixture includes 9a) a bimodal silicon nitride powder blend consisting essentially of about 10-30% by weight of a first silicon mitride powder of an average particle size of about 0.2 .mu.m and a surface area of about 8-12m.sup.2 g, and about 70-90% by weight of a second silicon nitride powder of an average particle size of about 0.4-0.6 .mu.m and a surface area of about 2-4 m.sup.2 /g, (b) about 10-50 percent by volume, based on the volume of the densified article, of refractory whiskers or fibers having an aspect ratio of about 3-150 and having an equivalent diameter selected to produce in the densified articel an equivalent diameter ratio of the whiskers or fibers to grains of silicon nitride of greater than 1.0, and (c) an effective amount of a suitable oxide densification aid. The green body is formed from the powder mixture, an effective amount of a suitable oxide densification aid, and an effective amount of a suitable organic binder.

Huckabee, Marvin L. (Marlboro, MA); Buljan, Sergej-Tomislav (Acton, MA); Neil, Jeffrey T. (Acton, MA)

1991-01-01T23:59:59.000Z

259

Ion exchange separation of plutonium and gallium (1) resource and inventory requirements, (2) waste, emissions, and effluent, and (3) facility size  

SciTech Connect

The following report summarizes an effort intended to estimate within an order-of-magnitude the (1) resource and inventory requirements, (2) waste, emissions, and effluent amounts, and (3) facility size, for ion exchange (IX) separation of plutonium and gallium. This analysis is based upon processing 3.5 MT-Pu/yr. The technical basis for this summary is detailed in a separate document, {open_quotes}Preconceptual Design for Separation of Plutonium and Gallium by Ion Exchange{close_quotes}. The material balances of this separate document are based strictly on stoichiometric amounts rather than details of actual operating experience, in order to avoid classification as Unclassified Controlled Nuclear Information. This approximation neglets the thermodynamics and kinetics which can significantly impact the amount of reagents required. Consequently, the material resource requirements and waste amounts presented here would normally be considered minimums for processing 3.5 MT-Pu/yr; however, the author has compared the inventory estimates presented with that of an actual operating facility and found them similar. Additionally, the facility floor space presented here is based upon actual plutonium processing systems and can be considered a nominal estimate.

DeMuth, S.

1997-09-30T23:59:59.000Z

260

The effect of hydrogen-plasma and PECVD-nitride deposition on bulk and surface passivation in string-ribbon silicon solar cells  

DOE Green Energy (OSTI)

We have investigated whether an in-situ hydrogen or ammonia rf-plasma treatment prior to a PECVD-nitride deposition would promote bulk defect passivation independently of surface effects. We also studied whether the predeposition of a thin silicon-nitride protective layer vbefore performing the plasma treatment would serve to minimize surface damage. We found that for the limited set of deposition conditions in of cells processed using the used five different deposition strategies and compared the resulting cell performance with that investigated so far, the direct deposition of PECVD-nitride produces the best cells on String Ribbon silicon wafers to date, with efficiencies up to 14.5%. Hydrogen and ammonia plasma pretreatments without a protective nitride layer resulted in better bulk passivation, but damaged surfaces. Pretreatments after deposition of the protective layer produced the best surface passivation, but were not effective in passivating the bulk.

Ruby, D.S. [Sandia National Labs., Albuquerque, NM (United States); Wilbanks, W.L.; Fleddermann, C.B. [New Mexico Univ., Albuquerque, NM (United States); Hanoka, J.I. [Evergreen Solar Inc., Waltham, MA (United States)

1995-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "gallium nitride ingan" from the National Library of EnergyBeta (NLEBeta).
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to obtain the most current and comprehensive results.


261

Issues associated with the metalorganic chemical vapor deposition of ScGaN and YGaN alloys.  

SciTech Connect

The most energy efficient solid state white light source will likely be a combination of individually efficient red, green, and blue LED. For any multi-color approach to be successful the efficiency of deep green LEDs must be significantly improved. While traditional approaches to improve InGaN materials have yielded incremental success, we proposed a novel approach using group IIIA and IIIB nitride semiconductors to produce efficient green and high wavelength LEDs. To obtain longer wavelength LEDs in the nitrides, we attempted to combine scandium (Sc) and yttrium (Y) with gallium (Ga) to produce ScGaN and YGaN for the quantum well (QW) active regions. Based on linear extrapolation of the proposed bandgaps of ScN (2.15 eV), YN (0.8 eV) and GaN (3.4 eV), we expected that LEDs could be fabricated from the UV (410 nm) to the IR (1600 nm), and therefore cover all visible wavelengths. The growth of these novel alloys potentially provided several advantages over the more traditional InGaN QW regions including: higher growth temperatures more compatible with GaN growth, closer lattice matching to GaN, and reduced phase separation than is commonly observed in InGaN growth. One drawback to using ScGaN and YGaN films as the active regions in LEDs is that little research has been conducted on their growth, specifically, are there metalorganic precursors that are suitable for growth, are the bandgaps direct or indirect, can the materials be grown directly on GaN with a minimal defect formation, as well as other issues related to growth. The major impediment to the growth of ScGaN and YGaN alloys was the low volatility of metalorganic precursors. Despite this impediment some progress was made in incorporation of Sc and Y into GaN which is detailed in this report. Primarily, we were able to incorporate up to 5 x 10{sup 18} cm{sup -3} Y atoms into a GaN film, which are far below the alloy concentrations needed to evaluate the YGaN optical properties. After a no-cost extension was granted on this program, an additional more 'liquid-like' Sc precursor was evaluated and the nitridation of Sc metals on GaN were investigated. Using the Sc precursor, dopant level quantities of Sc were incorporated into GaN, thereby concluding the growth of ScGaN and YGaN films. Our remaining time during the no-cost extension was focused on pulsed laser deposition of Sc metal films on GaN, followed by nitridation in the MOCVD reactor to form ScN. Finally, GaN films were deposited on the ScN thin films in order to study possible GaN dislocation reduction.

Koleske, Daniel David; Knapp, James Arthur; Lee, Stephen Roger; Crawford, Mary Hagerott; Creighton, James Randall; Cross, Karen Charlene; Thaler, Gerald

2009-07-01T23:59:59.000Z

262

Gold Nanoparticles Supported on Carbon Nitride: Influence of Surface Hydroxyls on Low Temperature Carbon Monoxide Oxidation  

SciTech Connect

This paper reports the synthesis of 2.5 nm gold clusters on the oxygen free and chemically labile support carbon nitride (C3N4). Despite having small particle sizes and high enough water partial pressure these Au/C3N4 catalysts are inactive for the gas phase and liquid phase oxidation of carbon monoxide. The reason for the lack of activity is attributed to the lack of surface OH groups on the C3N4. These OH groups are argued to be responsible for the activation of CO in the oxidation of CO. The importance of basic OH groups explains the well document dependence of support isoelectric point versus catalytic activity.

Singh, Joseph A [ORNL; Dudney, Nancy J [ORNL; Li, Meijun [ORNL; Overbury, Steven {Steve} H [ORNL; Veith, Gabriel M [ORNL

2012-01-01T23:59:59.000Z

263

Vacancies in fully hydrogenated boron nitride layer: implications for functional nanodevices  

SciTech Connect

Using density functional theory, a series of calculations of structural and electronic properties of hydrogen vacancies in a fully hydrogenated boron nitride (fH-BN) layer were conducted. By dehydrogenating the fH-BN structure, B-terminated vacancies can be created which induce complete spin polarization around the Fermi level, irrespective of the vacancy size. On the contrary, the fH-BN structure with N-terminated vacancies can be a small-gap semiconductor, a typical spin gapless semiconductor, or a metal depending on the vacancy size. Utilizing such vacancy-induced band gap and magnetism changes, possible applications in spintronics are proposed, and a special fH-BN based quantum dot device is designed.

Zhou, Yungang; Wang, Zhiguo; Nie, JL; Yang, Ping; Sun, Xin; Khaleel, Mohammad A.; Zu, Xiaotao; Gao, Fei

2012-03-01T23:59:59.000Z

264

Energy transfer and 1.54 {mu}m emission in amorphous silicon nitride films  

Science Conference Proceedings (OSTI)

Er-doped amorphous silicon nitride films with various Si concentrations (Er:SiN{sub x}) were fabricated by reactive magnetron cosputtering followed by thermal annealing. The effects of Si concentrations and annealing temperatures were investigated in relation to Er emission and excitation processes. Efficient excitation of Er ions was demonstrated within a broad energy spectrum and attributed to disorder-induced localized transitions in amorphous Er:SiN{sub x}. A systematic optimization of the 1.54 {mu}m emission was performed and a fundamental trade-off was discovered between Er excitation and emission efficiency due to excess Si incorporation. These results provide an alternative approach for the engineering of sensitized Si-based light sources and lasers.

Yerci, S.; Li, R. [Department of Electrical and Computer Engineering, Boston University, 8 Saint Mary's Street, Boston, Massachusetts 02215-2421 (United States); Kucheyev, S. O.; Buuren, T. van [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States); Basu, S. N. [Division of Materials Science and Engineering, Boston University, 15 Saint Mary's Street, Brookline, Massachusetts 02446 (United States); Department of Mechanical Engineering, Boston University, 110 Cummington Street, Boston, Massachusetts 02215 (United States); Dal Negro, L. [Department of Electrical and Computer Engineering, Boston University, 8 Saint Mary's Street, Boston, Massachusetts 02215-2421 (United States); Division of Materials Science and Engineering, Boston University, 15 Saint Mary's Street, Brookline, Massachusetts 02446 (United States)

2009-07-20T23:59:59.000Z

265

Steel bonded dense silicon nitride compositions and method for their fabrication  

DOE Patents (OSTI)

A two-stage bonding technique for bonding high density silicon nitride and other ceramic materials to stainless steel and other hard metals, and multilayered ceramic-metal composites prepared by the technique are disclosed. The technique involves initially slurry coating a surface of the ceramic material at about 1500/sup 0/C in a vacuum with a refractory material and the stainless steel is then pressure bonded to the metallic coated surface by brazing it with nickel-copper-silver or nickel-copper-manganese alloys at a temperature in the range of about 850/sup 0/ to 950/sup 0/C in a vacuum. The two-stage bonding technique minimizes the temperature-expansion mismatch between the dissimilar materials.

Landingham, R.L.; Shell, T.E.

1985-05-20T23:59:59.000Z

266

Oxides and nitrides as alternative plasmonic materials in the optical range  

E-Print Network (OSTI)

As alternatives to conventional metals, new plasmonic materials offer many advantages in the rapidly growing fields of plasmonics and metamaterials. These advantages include low intrinsic loss, semiconductor-based design, compatibility with standard nanofabrication processes, tunability, and others. Transparent conducting oxides such as Al:ZnO, Ga:ZnO and indium-tin-oxide (ITO) enable many high-performance metamaterial devices operating in the near-IR. Transition-metal nitrides such as TiN or ZrN can be substitutes for conventional metals in the visible frequencies. In this paper we provide the details of fabrication and characterization of these new materials and discuss their suitability for a number of metamaterial and plasmonic applications.

Naik, Gururaj V; Boltasseva, Alexandra

2011-01-01T23:59:59.000Z

267

Dilute Group III-V nitride intermediate band solar cells with contact blocking layers  

DOE Patents (OSTI)

An intermediate band solar cell (IBSC) is provided including a p-n junction based on dilute III-V nitride materials and a pair of contact blocking layers positioned on opposite surfaces of the p-n junction for electrically isolating the intermediate band of the p-n junction by blocking the charge transport in the intermediate band without affecting the electron and hole collection efficiency of the p-n junction, thereby increasing open circuit voltage (V.sub.OC) of the IBSC and increasing the photocurrent by utilizing the intermediate band to absorb photons with energy below the band gap of the absorber layers of the IBSC. Hence, the overall power conversion efficiency of a IBSC will be much higher than an conventional single junction solar cell. The p-n junction absorber layers of the IBSC may further have compositionally graded nitrogen concentrations to provide an electric field for more efficient charge collection.

Walukiewicz, Wladyslaw (Kensington, CA); Yu, Kin Man (Lafayette, CA)

2012-07-31T23:59:59.000Z

268

Picosecond laser structuration under high pressures: Observation of boron nitride nanorods  

SciTech Connect

We report on picosecond UV-laser processing of hexagonal boron nitride (BN) at moderately high pressures above 500 bar. The main effect is specific to the ambient gas and laser pulse duration in the ablation regime: when samples are irradiated by 5 or 0.45 ps laser pulses in nitrogen gas environment, multiple nucleation of a new crystalline product-BN nanorods-takes place. This process is triggered on structural defects, which number density strongly decreases upon recrystallization. Nonlinear photon absorption by adsorbed nitrogen molecules is suggested to mediate the nucleation growth. High pressure is responsible for the confinement and strong backscattering of ablation products. A strong surface structuring also appears at longer 150 ps laser irradiation in similar experimental conditions. However, the transformed product in this case is amorphous strongly contaminated by boron suboxides B{sub x}O{sub y}.

Museur, Luc [Laboratoire de Physique des Lasers-LPL CNRS, Institut Galilee, Universite Paris 13, 93430 Villetaneuse (France); Petitet, Jean-Pierre; Kanaev, Andrei V. [Laboratoire d' Ingenierie des Materiaux et des Hautes Pressions-LIMHP CNRS, Institut Galilee, Universite Paris 13, 93430 Villetaneuse (France); Michel, Jean-Pierre [Laboratoire d' Ingenierie des Materiaux et des Hautes Pressions-LIMHP CNRS, Institut Galilee, Universite Paris 13, 93430 Villetaneuse (France); Laboratoire des Proprietes Mecaniques et Thermodynamiques des Materiaux-LPMTM CNRS, Institut Galilee, Universite Paris 13, 93430 Villetaneuse (France); Marine, Wladimir [Centre Interdisciplinaire de Nanoscience de Marseille-CINaM, UPR CNRS 3118, Faculte des Science de Luminy, 13288 Marseille (France); Anglos, Demetrios [Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas (IESL-FORTH), 71110 Heraklion, Crete (Greece); Fotakis, Costas [Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas (IESL-FORTH), 71110 Heraklion, Crete (Greece); Department of Physics, University of Crete, Heraklion, Crete (Greece)

2008-11-01T23:59:59.000Z

269

Evolution of oxidation and creep damage mechanisms in HIPed silicon nitride materials  

DOE Green Energy (OSTI)

Several yttria-fluxed, hot-isostatically pressed (HIPed) silicon nitrides have been tensile creep tested at temperatures representative of gas turbine engines. Creep and oxidation assisted damage mechanisms concurrently evolve when these materials are tested at high temperatures and low stresses (i.e., long exposure times at temperature). Atmospheric creep testing results in creation of oxygen and yttrium gradients across the radial dimension. High concentrations of oxygen and yttrium coincide with dense populations of lenticular-shaped cavities near the surface of crept specimens. The center of the tensile specimens was devoid of oxygen or yttrium; in addition, lenticular cavities were rare. The gradient in lenticular-cavity concentration is coincident with the oxygen and yttrium gradients. Stress corrosion cracking (SCC) also occurs in these HIPed silicon nitrides when they are subjected to stress at high temperatures in ambient air. The size of this damage zone increases when the temperature is higher and/or the applied stress is lower. Stress-corrosion cracking initiates at the surface of the tensile specimen and advances radially inwards. What nucleates SCC has not yet been identified, but it is believed to result from a stress-concentrator (e.g., machining damage) at the surface and its growth is a result of coalescence of microcracks and cavities. The higher concentration of oxygen and yttrium in the grain boundaries near the specimen`s surface lessens the local high temperature mechanical integrity; this is believed to be associated with the growth of the SCC zone. This SCC zone continues to grow in size during tensile loading until it reaches a critical size which causes fracture.

Wereszczak, A.A.; Ferber, M.K.; Kirkland, T.P.; More, K.L.

1994-10-01T23:59:59.000Z

270

Crystal and Electronic Structures of Neptunium Nitrides Synthesized Using a Fluoride Route  

SciTech Connect

A low-temperature fluoride route was utilized to synthesize neptunium mononitride, NpN. Through the development of this process, two new neptunium nitride species, NpN{sub 2} and Np{sub 2}N{sub 3}, were identified. The NpN{sub 2} and Np{sub 2}N{sub 3} have crystal structures isomorphous to those of UN{sub 2} and U{sub 2}N{sub 3}, respectively. NpN{sub 2} crystallizes in a face-centered cubic CaF{sub 2}-type structure with a space group of Fm3m and a refined lattice parameter of 5.3236(1) {angstrom}. The Np{sub 2}N{sub 3} adopts the body-centered cubic Mn{sub 2}O{sub 3}-type structure with a space group of Ia{bar 3}. Its refined lattice parameter is 10.6513(4) {angstrom}. The NpN synthesis at temperatures {le} 900 C using the fluoride route discussed here was also demonstrated. Previous computational studies of the neptunium nitride system have focused exclusively on the NpN phase because no evidence was reported experimentally on the presence of NpN{sub x} systems. Here, the crystal structures of NpN{sub 2} and Np{sub 2}N{sub 3} are discussed for the first time, confirming the experimental results by density functional calculations (DFT). These DFT calculations were performed within the local-density approximation (LDA+U) and the generalized-gradient approximation (GGA+U) corrected with an effective Hubbard parameter to account for the strong on-site Coulomb repulsion between Np 5f electrons. The effects of the spin-orbit coupling in the GGA+U calculations have also been investigated for NpN{sub 2} and NpN.

Silva, G W Chinthaka M [ORNL; Weck, Dr. Phil F. [Sandia National Laboratories (SNL); Eunja, Dr. Kim [University of Nevada, Las Vegas; Yeamans, Dr. Charles B. [Lawrence Livermore National Laboratory (LLNL); Cerefice, Gary S. [University of Nevada, Las Vegas; Sattelberger, Alfred P [Argonne National Laboratory (ANL); Czerwinski, Ken R. [University of Nevada, Las Vegas

2012-01-01T23:59:59.000Z

271

Highest transmittance and high-mobility amorphous indium gallium zinc oxide films on flexible substrate by room-temperature deposition and post-deposition anneals  

Science Conference Proceedings (OSTI)

Amorphous indium gallium zinc oxide (a-IGZO) thin films of the highest transmittance reported in literature were initially deposited onto flexible polymer substrates at room temperature. The films were annealed in vacuum, air, and oxygen to enhance their electrical and optical performances. Electrical and optical characterizations were done before and after anneals. A partial reversal of the degradation in electrical properties upon annealing in oxygen was achieved by subjecting the films to subsequent vacuum anneals. A model was developed based on film texture and structural defects which showed close agreement between the measured and calculated carrier mobility values at low carrier concentrations (2-6 x 10{sup 19} cm{sup -3}).

Gadre, Mandar J. [School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona 85287 (United States); Alford, T. L. [School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona 85287 (United States); Flexible Display Center at Arizona State University, Tempe, Arizona 85284 (United States)

2011-08-01T23:59:59.000Z

272

Nitrides I  

Science Conference Proceedings (OSTI)

May 24, 2010... Lincoln Laboratory, Lexington, MA, USA; Rajaram Bhat, Corning Inc ... Clemens Wächter1; Alexander Meyer1; Peter Michler1; 1Universität ...

273

Nitrides III  

Science Conference Proceedings (OSTI)

May 28, 2010... Lincoln Laboratory, Lexington, MA, USA; Rajaram Bhat, Corning Inc ... Jürgen Bläsing1; Armin Dadgar1; Thomas Hempel1; Peter Veit1; Alois ...

274

N-polar III-nitride quantum well light-emitting diodes with polarization-induced doping  

Science Conference Proceedings (OSTI)

Nitrogen-polar III-nitride heterostructures present unexplored advantages over Ga(metal)-polar crystals for optoelectronic devices. This work reports N-polar III-nitride quantum-well ultraviolet light-emitting diodes grown by plasma-assisted molecular beam epitaxy that integrate polarization-induced p-type doping by compositional grading from GaN to AlGaN along N-face. The graded AlGaN layer simultaneously acts as an electron blocking layer while facilitating smooth injection of holes into the active region, while the built-in electric field in the barriers improves carrier injection into quantum wells. The enhanced doping, carrier injection, and light extraction indicate that N-polar structures have the potential to exceed the performance of metal-polar ultraviolet light-emitting diodes.

Verma, Jai; Simon, John; Protasenko, Vladimir; Kosel, Thomas; Xing, Huili Grace; Jena, Debdeep [Department of Electrical Engineering, University of Notre Dame, Indiana 46556 (United States)

2011-10-24T23:59:59.000Z

275

Three Alkali-Metal-Gold-Gallium Systems. Ternary Tunnel Structures and Some Problems with Poorly Ordered Cations  

SciTech Connect

Six new intermetallic compounds have been characterized in the alkali metal (A = Na, Rb, Cs)–gold–gallium systems. Three isostructural compounds with the general composition A0.55Au2Ga2, two others of AAu3Ga2 (A = Rb, Cs), and the related Na13Au41.2Ga30.3 were synthesized via typical high-temperature reactions and their crystal structures determined by single-crystal X-ray diffraction analysis: Na0.56(9)Au2Ga2 (I, I4/mcm, a = 8.718(1) Ĺ, c = 4.857(1) Ĺ, Z = 4), Rb0.56(1)Au2Ga2 (II, I4/mcm, a = 8.950(1) Ĺ, c = 4.829(1) Ĺ, Z = 4), Cs0.54(2)Au2Ga2 (III, I4/mcm, a = 9.077(1) Ĺ, c = 4.815(1) Ĺ, Z = 4), RbAu3Ga2 (IV, Pnma, a = 13.384(3) Ĺ, b = 5.577(1) Ĺ, c = 7.017(1) Ĺ, Z = 4), CsAu3Ga2 (V, Pnma, a = 13.511(3) Ĺ, b = 5.614(2) Ĺ, c = 7.146(1) Ĺ, Z = 4), Na13Au41.2(1)Ga30.3(1) (VI, P6 mmm, a = 19.550(3) Ĺ, c = 8.990(2) Ĺ, Z = 2). The first three compounds (I–III) are isostructural with tetragonal K0.55Au2Ga2 and likewise contain planar eight-member Au/Ga rings that stack along c to generate tunnels and that contain varying degrees of disordered Na–Cs cations. The cation dispositions are much more clearly and reasonably defined by electron density mapping than through least-squares refinements with conventional anisotropic ellipsoids. Orthorhombic AAu3Ga2 (IV, V) are ordered ternary Rb and Cs derivatives of the SrZn5 type structure, demonstrating structural variability within the AAu3Ga2 family. All attempts to prepare an isotypic “NaAu3Ga2” were not successful, but yielded only a similar composition Na13Au41.2Ga30.3 (NaAu3.17Ga2.33) (VI) in a very different structure with two types of cation sites. Crystal orbital Hamilton population (COHP) analysis obtained from tight-binding electronic structure calculations for idealized I–IV via linear muffin-tin-orbital (LMTO) methods emphasized the major contributions of heteroatomic Au–Ga bonding to the structural stability of these compounds. The relative minima (pseudogaps) in the DOS curves for IV correspond well with the valence electron counts of known representatives of this structure type and, thereby, reveal some magic numbers to guide the search for new isotypic compounds. Theoretical calculation of total energies vs volumes obtained by VASP (Vienna Ab initio Simulation Package) calculations for KAu3Ga2 and RbAu3Ga2 suggest a possible transformation from SrZn5- to BaZn5-types at high pressure.

Smetana, Volodymyr; Miller, Gordon J.; Corbett, John D.

2012-06-27T23:59:59.000Z

276

Application of Self-Propagating High Temperature Synthesis to the Fabrication of Actinide Bearing Nitride and Other Ceramic Nuclear Fuels  

Science Conference Proceedings (OSTI)

The high vapor pressures of americium (Am) and americium nitride (AmN) are cause for concern in producing nitride ceramic nuclear fuel that contains Am. Along with the problem of Am retention during the sintering phases of current processing methods, are additional concerns of producing a consistent product of desirable homogeneity, density and porosity. Similar difficulties have been experienced during the laboratory scale process development stage of producing metal alloys containing Am wherein compact powder sintering methods had to be abandoned. Therefore, there is an urgent need to develop a low-temperature or low–heat fuel fabrication process for the synthesis of Am-containing ceramic fuels. Self-propagating high temperature synthesis (SHS), also called combustion synthesis, offers such an alternative process for the synthesis of Am nitride fuels. Although SHS takes thermodynamic advantage of the high combustion temperatures of these exothermic SHS reactions to synthesize the required compounds, the very fast heating, reaction and cooling rates can kinetically generate extremely fast reaction rates and facilitate the retention of volatile species within the rapidly propagating SHS reaction front. The initial objective of the research program is to use Mn as the surrogate for Am to synthesize a reproducible, dense, high quality Zr-Mn-N ceramic compound. Having determined the fundamental SHS reaction parameters and optimized SHS processing steps using Mn as the surrogate for Am, the technology will be transferred to Idaho National Laboratory to successfully synthesize a high quality Zr-Am-N ceramic fuel.

John J. Moore, Douglas E. Burkes, Collin D. Donohoue, Marissa M. Reigel, J. Rory Kennedy

2009-05-18T23:59:59.000Z

277

Methods for and products of processing nanostructure nitride, carbonitride and oxycarbonitride electrode power materials by utilizing sol gel technology for supercapacitor applications  

SciTech Connect

Metal nitride, carbonitride, and oxycarbonitride powder with high surface area (up to 150 m.sup.2 /g) is prepared by using sol-gel process. The metal organic precursor, alkoxides or amides, is synthesized firstly. The metal organic precursor is modified by using unhydrolyzable organic ligands or templates. A wet gel is formed then by hydrolysis and condensation process. The solvent in the wet gel is then be removed supercritically to form porous amorphous hydroxide. This porous hydroxide materials is sintered to 725.degree. C. under the ammonia flow and porous nitride powder is formed. The other way to obtain high surface area nitride, carbonitride, and oxycarbonitride powder is to pyrolyze polymerized templated metal amides aerogel in an inert atmosphere. The electrochemical capacitors are prepared by using sol-gel prepared nitride, carbonitride, and oxycarbonitride powder. Two methods are used to assemble the capacitors. Electrode is formed either by pressing the mixture of nitride powder and binder to a foil, or by depositing electrode coating onto metal current collector. The binder or coating is converted into a continuous network of electrode material after thermal treatment to provide enhanced energy and power density. Liquid electrolyte is soaked into porous electrode. The electrochemical capacitor assembly further has a porous separator layer between two electrodes/electrolyte and forming a unit cell.

Huang, Yuhong (West Hills, CA); Wei, Oiang (West Hills, CA); Chu, Chung-tse (Chatsworth, CA); Zheng, Haixing (Oak Park, CA)

2001-01-01T23:59:59.000Z

278

Silicon surface and bulk defect passivation by low temperature PECVD oxides and nitrides  

DOE Green Energy (OSTI)

The effectiveness of PECVD passivation of surface and bulk defects in Si, as well as phosphorous diffused emitters, Is investigated and quantified. Significant hydrogen incorporation coupled with high positive charge density in the PECVD SiN layer is found to play an important role in bulk and surface passivation. It is shown that photo-assisted anneal in a forming gas ambient after PECVD depositions significantly improves the passivation of emitter and bulk defects. PECVD passivation of phosphorous doped emitters and boron doped bare Si surfaces is found to be a strong function of doping concentration. Surface recombination velocity of less than 200 cm/s for 0.2 Ohm-cm and less than 1 cm/s for high resistivity substrates ({approximately} Ohm-cm) were achieved. PECVD passivation improved bulk lifetime in the range of 30% to 70% in multicrystalline Si materials. However, the degree of the passivation was found to be highly material specific. Depending upon the passivation scheme, emitter saturation current density (J{sub oe}) can be reduced by a factor of 3 to 9. Finally, the stability of PECVD oxide/nitride passivation under prolonged UV exposure is established.

Chen, Z.; Rohatgi, A. [Georgia Institute of Technology, Atlanta, GA (United States). Univ. Center of Excellence for Photovoltaics Research and Education; Ruby, D. [Sandia National Labs., Albuquerque, NM (United States)

1995-01-01T23:59:59.000Z

279

Influence of nitrogen background pressure on structure of niobium nitride films grown by pulsed laser deposition  

SciTech Connect

Depositions of niobium nitride thin films on Nb using pulsed laser deposition (PLD) with different nitrogen background pressures (10.7 to 66.7 Pa) have been performed. The effect of nitrogen pressure on NbN formation in this process was examined. The deposited films were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscope (AFM), and energy dispersive X-ray (EDX) analysis. Hexagonal {beta}-Nb{sub 2}N and cubic {delta}-NbN phases resulted when growth was performed in low nitrogen background pressures. With an increase in nitrogen pressure, NbN films grew in single hexagonal {beta}-Nb{sub 2}N phase. The formation of the hexagonal texture during the film growth was studied. The c/a ratio of the hexagonal {beta}-Nb{sub 2}N unit cell parameter increases with increasing nitrogen pressure. Furthermore, the N:Nb ratio has a strong influence on the lattice parameter of the {delta}-NbN, where the highest value was achieved for this ratio was 1.19. It was found that increasing nitrogen background pressure leads to change in the phase structure of the NbN film. With increasing nitrogen pressure, the film structure changes from hexagonal to a mixed phase and then back to a hexagonal phase.

Ashraf H. Farha, Ali O. Er, Yüksel Ufuktepe, Ganapati Myneni, Hani E. Elsayed-Ali

2011-12-01T23:59:59.000Z

280

High Temperature Annealing Studies on the Piezoelectric Properties of Thin Aluminum Nitride Films  

Science Conference Proceedings (OSTI)

A Rapid Thermal Annealing (RTA) system was used to anneal sputtered and MOVPE grown Aluminum Nitride (AlN) thin films at temperatures up to 1000°C in ambient and controlled environments. According to Energy Dispersive X-Ray Analysis (EDAX), the films annealed in an ambient environment rapidly oxidize after five minutes at 1000°C. Below 1000°C the films oxidized linearly as a function of annealing temperature which is consistent with what has been reported in literature [1]. Laser Doppler Vibrometry (LDV) was used to measure the piezoelectric coefficient, d33, of these films. Films annealed in an ambient environment had a weak piezoelectric response indicating that oxidation on the surface of the film reduces the value of d33. A high temperature furnace has been built that is capable of taking in-situ measurements of the piezoelectric response of AlN films. In-situ d33 measurements are recorded up to 300°C for both sputtered and MOVPE-grown AlN thin films. The measured piezoelectric response appears to increase with temperature up to 300°C possibly due to stress in the film.

R. Farrell; V. R. Pagan; A. Kabulski; Sridhar Kuchibhatl; J. Harman; K. R. Kasarla; L. E. Rodak; P. Famouri; J. Peter Hensel; D. Korakakis

2008-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "gallium nitride ingan" from the National Library of EnergyBeta (NLEBeta).
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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

High Temperature Annealing Studies on the Piezoelectric Properties of Thin Aluminum Nitride Films  

Science Conference Proceedings (OSTI)

A Rapid Thermal Annealing (RTA) system was used to anneal sputtered and MOVPE-grown Aluminum Nitride (AlN) thin films at temperatures up to 1000°C in ambient and controlled environments. According to Energy Dispersive X-Ray Analysis (EDAX), the films annealed in an ambient environment rapidly oxidize after five minutes at 1000°C. Below 1000°C the films oxidized linearly as a function of annealing temperature which is consistent with what has been reported in literature [1]. Laser Doppler Vibrometry (LDV) was used to measure the piezoelectric coefficient, d33, of these films. Films annealed in an ambient environment had a weak piezoelectric response indicating that oxidation on the surface of the film reduces the value of d33. A high temperature furnace has been built that is capable of taking in-situ measurements of the piezoelectric response of AlN films. In-situ d33 measurements are recorded up to 300°C for both sputtered and MOVPE-grown AlN thin films. The measured piezoelectric response appears to increase with temperature up to 300°C possibly due to stress in the film.

Farrell, R.; Pagan, V.R.; Kabulski, A.; Kuchibhatla, S.; Harman, J.; Kasarla, K.R.; Rodak, L.E.; Hensel, J.P.; Famouri, P.; Korakakis, D.

2008-01-01T23:59:59.000Z

282

Structure and composition of nanometer-sized nitrides in a creep resistant cast austenitic alloy  

SciTech Connect

The microstructure of a new and improved high-temperature creep-resistant cast austenitic alloy, CF8C-Plus, was characterized after creep-rupture testing at 1023 K (750 C) and 100 MPa. Microstructures were investigated by detailed scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray spectroscopy (EDS). Principal component analysis of EDS spectrum images was used to examine the complex precipitate morphology. Thermodynamic modeling was performed to predict equilibrium phases in this alloy as well as the compositions of these phases at relevant temperatures. The improved high-temperature creep strength of CF8C-Plus over its predecessor CF8C is suggested to be due to the modified microstructure and phase stability in the alloy, including the absence of {delta}-ferrite in the as-cast condition and the development of a stable, slow-growing precipitation hardening nitride phase - the tetragonal Z-phase - which has not been observed before in cast austenitic stainless steels.

Evans, Neal D [ORNL; Maziasz, Philip J [ORNL; Shingledecker, John P. [Electric Power Research Institute (EPRI); Pollard, Michael J [Caterpillar Technical Center

2010-01-01T23:59:59.000Z

283

Carbide/nitride grain refined rare earth-iron-boron permanent magnet and method of making  

DOE Patents (OSTI)

A method of making a permanent magnet wherein 1) a melt is formed having a base alloy composition comprising RE, Fe and/or Co, and B (where RE is one or more rare earth elements) and 2) TR (where TR is a transition metal selected from at least one of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, and Al) and at least one of C and N are provided in the base alloy composition melt in substantially stoichiometric amounts to form a thermodynamically stable compound (e.g. TR carbide, nitride or carbonitride). The melt is rapidly solidified in a manner to form particulates having a substantially amorphous (metallic glass) structure and a dispersion of primary TRC, TRN and/or TRC/N precipitates. The amorphous particulates are heated above the crystallization temperature of the base alloy composition to nucleate and grow a hard magnetic phase to an optimum grain size and to form secondary TRC, TRN and/or TRC/N precipitates dispersed at grain boundaries. The crystallized particulates are consolidated at an elevated temperature to form a shape. During elevated temperature consolidation, the primary and secondary precipitates act to pin the grain boundaries and minimize deleterious grain growth that is harmful to magnetic properties.

McCallum, R. William (Ames, IA); Branagan, Daniel J. (Ames, IA)

1996-01-23T23:59:59.000Z

284

Antifuse with a single silicon-rich silicon nitride insulating layer  

DOE Patents (OSTI)

An antifuse is disclosed which has an electrically-insulating region sandwiched between two electrodes. The electrically-insulating region has a single layer of a non-hydrogenated silicon-rich (i.e. non-stoichiometric) silicon nitride SiN.sub.X with a nitrogen content X which is generally in the range of 0

Habermehl, Scott D.; Apodaca, Roger T.

2013-01-22T23:59:59.000Z

285

Application of Self-Propagating High Temperature Synthesis to the Fabrication of Actinide Bearing Nitride and Other Ceramic Nuclear Fuels  

SciTech Connect

The project uses an exothermic combustion synthesis reaction, termed self-propagating high-temperature synthesis (SHS), to produce high quality, reproducible nitride fuels and other ceramic type nuclear fuels (cercers and cermets, etc.) in conjunction with the fabrication of transmutation fuels. The major research objective of the project is determining the fundamental SHS processing parameters by first using manganese as a surrogate for americium to produce dense Zr-Mn-N ceramic compounds. These fundamental principles will then be transferred to the production of dense Zr-Am-N ceramic materials. A further research objective in the research program is generating fundamental SHS processing data to the synthesis of (i) Pu-Am-Zr-N and (ii) U-Pu-Am-N ceramic fuels. In this case, Ce will be used as the surrogate for Pu, Mn as the surrogate for Am, and depleted uranium as the surrogate for U. Once sufficient fundamental data has been determined for these surrogate systems, the information will be transferred to Idaho National Laboratory (INL) for synthesis of Zr-Am-N, Pu-Am-Zr-N and U-Pu-Am-N ceramic fuels. The high vapor pressures of americium (Am) and americium nitride (AmN) are cause for concern in producing nitride ceramic nuclear fuel that contains Am. Along with the problem of Am retention during the sintering phases of current processing methods, are additional concerns of producing a consistent product of desirable homogeneity, density and porosity. Similar difficulties have been experienced during the laboratory scale process development stage of producing metal alloys containing Am wherein compact powder sintering methods had to be abandoned. Therefore, there is an urgent need to develop a low-temperature or low–heat fuel fabrication process for the synthesis of Am-containing ceramic fuels. Self-propagating high temperature synthesis (SHS), also called combustion synthesis, offers such an alternative process for the synthesis of Am nitride fuels. Although SHS takes thermodynamic advantage of the high combustion temperatures of these exothermic SHS reactions to synthesize the required compounds, the very fast heating, reaction and cooling rates can kinetically generate extremely fast reaction rates and facilitate the retention of volatile species within the rapidly propagating SHS reaction front. The initial objective of the research program is to use Mn as the surrogate for Am to synthesize a reproducible, dense, high quality Zr-Mn-N ceramic compound. Having determined the fundamental SHS reaction parameters and optimized SHS processing steps using Mn as the surrogate for Am, the technology will be transferred to Idaho National Laboratory to successfully synthesize a high quality Zr-Am-N ceramic fuel.

John J. Moore, Marissa M. Reigel, Collin D. Donohoue

2009-04-30T23:59:59.000Z

286

Page not found | Department of Energy  

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

Categorical Exclusion Determination Advanced Epi Tools for Gallium Nitride LED (Light Emitting Diode) Devices CX(s) Applied: B3.6 Date: 03052010 Location(s): Santa Clara,...

287

CX-010974: Categorical Exclusion Determination | Department of...  

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

CX-010974: Categorical Exclusion Determination Advanced Low-Cost Silicon Carbide (SiC) and Gallium Nitride (GaN) Wide Bandgap Inverters for Under-the-Hood Electric Vehicle...

288

Power Electronics Reliability Kick Off Meeting ? Silicon Power...  

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

failure modes of post-silicon power electronic (PE) devices such as silicon carbide (SiC) and gallium nitride (GaN) switches. * Seek opportunities for condition monitoring (CM)...

289

CX-010973: Categorical Exclusion Determination | Department of...  

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

CX-010973: Categorical Exclusion Determination Advanced Low-Cost Silicon Carbide (SiC) and Gallium Nitride (GaN) Wide Bandgap Inverters for Under-the-Hood Electric Vehicle...

290

CX-001137: Categorical Exclusion Determination | Department of...  

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

Categorical Exclusion Determination Advanced Epi Tools for Gallium Nitride LED (Light Emitting Diode) Devices CX(s) Applied: B3.6 Date: 03052010 Location(s): Santa Clara,...

291

Categorical Exclusion Determinations: National Energy Technology...  

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

Categorical Exclusion Determination Advanced Epi Tools for Gallium Nitride LED (Light Emitting Diode) Devices CX(s) Applied: B3.6 Date: 03052010 Location(s): Santa Clara,...

292

NETL F 451.1-1/1 Categorical Exclusion (CX) Designation Form  

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

01042010 - 12312011 Santa Clara, Ca Advanced Epi Tools for Gallium Nitride Light Emitting Diode Devices To develop a multi-chamber system such as a two MOCVD chambers, one...

293

JEM Table of Contents: November 1995 - TMS  

Science Conference Proceedings (OSTI)

Doping of Gallium Nitride Using Disilane [pp. 1547-1550] A.E. Wickenden, L.B. Rowland, K. Doverspike, D.K. Gaskill, J.A. Freitas, Jr., D.S. Simons, and P.H. Chi.

294

Page not found | Department of Energy  

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

-High Performance Gallium Nitride High Electron Mobility Transistor Modules for Agile Power Electronics CX(s) Applied: B3.6 Date: 08052010 Location(s): California Office(s):...

295

JOURNAL DE PHYSIQUE Colloque C4, suppltfment au no 4, Tome 40, avril 1979, page C4-31 Magnetic inelastic scattering in uranium nitride  

E-Print Network (OSTI)

inelastic scattering in uranium nitride T. M. Holden, E. C. Svensson, W. J. L. Buyers and G. H. Lander, Illinois, U.S.A. RCsumC. -De tous les pnictures d'uranium de structure cubique, le nitrure d'uranium pour la comprBhensionde la structure tlectronique de l'ion uranium comme des ions actinides en gkn

Paris-Sud XI, Université de

296

Self-organized GaAs patterns on misoriented GaAs (111)B substrates using dilute nitrides by molecular beam epitaxy  

Science Conference Proceedings (OSTI)

Recently, the growth of patterned surfaces is being used to demonstrate the site control of the three-dimensional nanostructures, and in particular quantum dots. Nevertheless the pre-patterning techniques show some disadvantages. In this work, we report ... Keywords: Dilute nitrides, InAs, Molecular beam epitaxy, Patterned surface, Quantum dots

R. Gargallo; J. Miguel-Sánchez; Á. Guzmán; U. Jahn; E. Muńoz

2006-12-01T23:59:59.000Z

297

C. Wetzel et al MRS Internet J. Nitride Semicond. Res. 10, 2 (2005) 1 Development of High Power Green Light Emitting Diode Chips  

E-Print Network (OSTI)

Power Green Light Emitting Diode Chips C. Wetzel and T. Detchprohm Future Chips Constellation Abstract The development of high emission power green light emitting diodes chips using GaInN/GaN multi production-scale implementation of this green LED die process. Keywords: nitrides, light emitting diode

Wetzel, Christian M.

298

Impact of temperature increments on tunneling barrier height and effective electron mass for plasma nitrided thin SiO{sub 2} layer on a large wafer area  

SciTech Connect

Thermally grown SiO{sub 2} layers were treated by a plasma nitridation process realized in a vertical furnace. The combination of a pulsed-low frequency plasma and a microwave remote plasma with N{sub 2}/NH{sub 3}/He feed gas mixture was used to nitride the thermally grown SiO{sub 2} gate dielectrics of MIS structures. Temperature dependency of effective masses and the barrier heights for electrons in pure thermally grown SiO{sub 2} as well as plasma nitrided SiO{sub 2} in high electric field by means of Fowler-Nordheim regime was determined. It is frequently seen from the literature that either effective electron mass or barrier height (generally effective electron mass) is assumed to be a constant and, as a result, the second parameter is calculated under the chosen assumption. However, in contrast to general attitude of previous studies, this work does not make any such assumptions for the calculation of neither of these two important parameters of an oxide at temperature ranges from 23 to 110 deg. C for SiO{sub 2}, and 23 to 130 deg. C for nitrided oxide. It is also shown here that both parameters are affected from the temperature changes; respectively, the barrier height decreases while the effective mass increases as a result of elevated temperature in both pure SiO{sub 2} and plasma nitrided SiO{sub 2}. Therefore, one parameter could be miscalculated if the other parameter, i.e., effective mass of electron, was assumed to be a constant with respect to variable physical conditions like changing temperature. Additionally, the barrier heights were calculated just by taking constant effective masses for both types of oxides to be able to compare our results to common literature values.

Aygun, G. [Fraunhofer IISB, Schottkystrasse 10, 91058 Erlangen (Germany); Department of Physics, Izmir Institute of Technology, TR-35430 Urla, Izmir (Turkey); Roeder, G.; Erlbacher, T.; Wolf, M.; Schellenberger, M.; Pfitzner, L. [Fraunhofer IISB, Schottkystrasse 10, 91058 Erlangen (Germany)

2010-10-15T23:59:59.000Z

299

Low Temperature Chemical Vapor Deposition of Zirconium Nitride in a Fluidized Bed  

E-Print Network (OSTI)

The objective of this research was to design, assemble, and demonstrate the initial performance of a fluidized bed chemical vapor deposition (FB-CVD) system capable of producing thin, uniform zirconium nitride (ZrN) coatings (1 to 10 micrometers thick) on uranium-molybdenum (UMo) particulate fuel. Plate-type fuel with U-xMo (x = 3 to 10 wt.%) particle fuel dispersed in an aluminum matrix is under development at Idaho National Laboratory (INL) for the Reduced Enrichment for Research and Test Reactors (RERTR) program. Initial irradiation tests performed at INL in the Advanced Test Reactor (ATR) indicate an interaction layer forms between the fuel microspheres and the matrix at relatively high power levels. These power levels induce higher temperatures which enables uranium diffusion into the aluminum during irradiation, eventually causing fuel plate failure. The objective of this work was to create a process to mitigate the fuel/matrix interaction by forming a thin barrier coating on the surface of the U-xMo microspheres before incorporation into the dispersion fuel plate matrix. One of the main challenges in performance of the FB-CVD system was the effective fluidization of a powder whose physical characteristics (size, density) are continuously changing. To address this, two types of fluidized bed reaction vessels were designed and improved over the course of this research: a spouted fluidized bed and an inverted fluidized bed. Both reaction vessels utilized tetrakis(dimethylamino)zirconium (TDMAZ) and ammonia gas as precursors at atmospheric pressure. Tungsten wires and zirconia-silica (ZrO2-SiO2) microspheres were used as the substrates for the coating experiments. The substrate temperature and precursor gas flow were manipulated as the process variables. The FB-CVD system was successful in forming zirconium based coatings on surrogate microspheres with elevated levels of chemical impurities. At atmospheric pressure, coatings of thicknesses ranging from 0.5 micrometers to 1.5 micrometers were produced between temperatures of 250 degrees C and 350 degrees C. The deposited coatings were characterized using scanning electron microscopy, energy dispersive spectroscopy and wavelength dispersive spectroscopy.

Arrieta, Marie

2012-08-01T23:59:59.000Z

300

Nonlinear optical properties of low temperature annealed silicon-rich oxide and silicon-rich nitride materials for silicon photonics  

SciTech Connect

We investigate the nonlinear optical properties of Si-rich silicon oxide (SRO) and Si-rich silicon nitride (SRN) samples as a function of silicon content, annealing temperature, and excitation wavelength. Using the Z-scan technique, we measure the non-linear refractive index n{sub 2} and the nonlinear absorption coefficient {beta} for a large number of samples fabricated by reactive co-sputtering. Moreover, we characterize the nonlinear optical parameters of SRN in the broad spectral region 1100-1500 nm and show the strongest nonlinearity at 1500 nm. These results demonstrate the potential of the SRN matrix for the engineering of compact devices with enhanced Kerr nonlinearities for silicon photonics applications.

Minissale, S. [Photonics Center, Boston University, 8 Saint Mary's street, Boston, Massachusetts 02215-2421 (United States) and Division of Materials Science and Engineering, Boston University, 15 Saint Mary's Street, Brookline, Massachusetts 02446 (United States); Yerci, S. [Department of Electrical and Computer Engineering, Boston University, 8 Saint Mary's Street, Boston, Massachusetts 02215-2421 (United States); Dal Negro, L. [Photonics Center, Boston University, 8 Saint Mary's street, Boston, Massachusetts 02215-2421 (United States) and Division of Materials Science and Engineering, Boston University, 15 Saint Mary's Street, Brookline, Massachusetts 02446 (United States); Department of Electrical and Computer Engineering, Boston University, 8 Saint Mary's Street, Boston, Massachusetts 02215-2421 (United States)

2012-01-09T23:59:59.000Z

Note: This page contains sample records for the topic "gallium nitride ingan" 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

Excitation wavelength dependence of water-window line emissions from boron-nitride laser-produced plasmas  

Science Conference Proceedings (OSTI)

We investigated the effects of laser excitation wavelength on water-window emission lines of laser-produced boron-nitride plasmas. Plasmas are produced by focusing 1064 nm and harmonically generated 532 and 266 nm radiation from a Nd:YAG laser on BN target in vacuum. Soft x-ray emission lines in the water-window region are recorded using a grazing-incidence spectrograph. Filtered photodiodes are used to obtain complementary data for water-window emission intensity and angular dependence. Spectral emission intensity changes in nitrogen Ly-{alpha} and He-{alpha} are used to show how laser wavelength affects emission. Our results show that the relative intensity of spectral lines is laser wavelength dependent, with the ratio of Ly-{alpha} to He-{alpha} emission intensity decreasing as laser wavelength is shortened. Filtered photodiode measurements of angular dependence showed that 266 and 532 nm laser wavelengths produce uniform emission.

Crank, M.; Harilal, S. S.; Hassan, S. M.; Hassanein, A. [Center for Materials Under Extreme Environment, School of Nuclear Engineering, Purdue University, West Lafayette, Indiana 47907 (United States)

2012-02-01T23:59:59.000Z

302

High mobility two-dimensional electron gases in nitride heterostructures with high Al composition AlGaN alloy barriers  

Science Conference Proceedings (OSTI)

We report high-electron mobility nitride heterostructures with >70% Al composition AlGaN alloy barriers grown by molecular beam epitaxy. Direct growth of such AlGaN layers on GaN resulted in hexagonal trenches and a low mobility polarization-induced charge. By applying growth interruption at the heterojunction, the surface morphology improved dramatically and the room temperature two-dimensional electron gas (2DEG) mobility increased by an order of magnitude, exceeding 1300 cm{sup 2}/V s. The 2DEG density was tunable at 0.4-3.7x10{sup 13}/cm{sup 2} by varying the total barrier thickness (t). Surface barrier heights of the heterostructures were extracted and exhibited dependence on t.

Li Guowang; Cao Yu; Xing Huili Grace; Jena, Debdeep [Department of Electrical Engineering, University of Notre Dame, Indiana 46556 (United States)

2010-11-29T23:59:59.000Z

303

Comprehensive Model of Hydrogen Transport into a Solar Cell during Silicon Nitride Processing for Fire-Through Metallization  

DOE Green Energy (OSTI)

A mechanism for the transport of H into a Si solar cell during plasma-enhanced chemical vapor deposition (PECVD) of a hydrogenated silicon nitride (SiN:H) layer and its subsequent fire-through metallization process is described. The PECVD process generates process-induced traps, which ''store'' H at the surface of the solar cell. This stored H is released and diffuses rapidly into the bulk of Si during the high-temperature metallization-firing process. During the ramp-down, the diffused H associates with impurities and defects and passivates them. The firing step partially heals up the surface damage. The proposed model explains a variety of observations and experimental results.

Sopori, B.; Zhang, Y.; Reedy, R.; Jones, K.; Yan, Y.; Al-Jassim, M.; Bathey, B.; Kalejs, J.

2005-02-01T23:59:59.000Z

304

SF{sub 6}/O{sub 2} plasma effects on silicon nitride passivation of AlGaN/GaN high electron mobility transistors  

SciTech Connect

The effects of various plasma and wet chemical surface pretreatments on the electrical characteristics of AlGaN/GaN high electron mobility transistors (HEMTs) passivated with plasma-deposited silicon nitride were investigated. The results of pulsed IV measurements show that samples exposed to various SF{sub 6}/O{sub 2} plasma treatments have markedly better rf dispersion characteristics compared to samples that were either untreated or treated in wet buffered oxide etch prior to encapsulation. The improvement in these characteristics correlates with the reduction of carbon on the semiconductor surface as measured with x-ray photoelectron spectroscopy. HEMT channel sheet resistance was also affected by varying silicon nitride deposition parameters.

Meyer, David J.; Flemish, Joseph R.; Redwing, Joan M. [Materials Science and Engineering Department, Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

2006-11-27T23:59:59.000Z

305

Crystal field disorder effects in the optical spectra of Nd{sup 3+} and Yb{sup 3+}-doped calcium lithium niobium gallium garnets laser crystals and ceramics  

SciTech Connect

The optical spectroscopic properties of RE{sup 3+} (Nd, 1 at. % or Yb, 1 to 10 at. %)-doped calcium-lithium-niobium-gallium garnet (CLNGG) single crystals and ceramics in the 10 K-300 K range are analyzed. In these compositionally disordered materials, RE{sup 3+} substitute Ca{sup 2+} in dodecahedral sites and the charge compensation is accomplished by adjusting the proportion of Li{sup +}, Nb{sup 5+}, and Ga{sup 3+} to the doping concentration. The crystals and ceramics show similar optical spectra, with broad and structured (especially at low temperatures) bands whose shape depends on temperature and doping concentration. At 10 K, the Nd{sup 3+4}I{sub 9/2}{yields}{sup 4}F{sub 3/2,5/2} and Yb{sup 3+2}F{sub 7/2}{yields}{sup 2}F{sub 5/2} absorption bands, which show prospect for diode laser pumping, can be decomposed in several lines that can be attributed to centers with large differences in the crystal field. The positions of these components are the same, but the relative intensity depends on the doping concentration and two main centers dominate the spectra. Non-selective excitation evidences broad emission bands, of prospect for short-pulse laser emission, whereas the selective excitation reveals the particular emission spectra of the various centers. The modeling reveals that the nonequivalent centers correspond to RE{sup 3+} ions with different cationic combinations in the nearest octahedral and tetrahedral coordination spheres, and the most abundant two centers have 4Nb and, respectively, 3Nb1Li in the nearest octahedral sphere. At 300 K, the spectral resolution is lost. It is then inferred that the observed optical bands are envelopes of the spectra of various structural centers, whose resolution is determined by the relative contribution of the temperature-dependent homogeneous broadening and the effects of crystal field disordering (multicenter structure, inhomogeneous broadening). The relevance of spectroscopic properties for selection of pumping conditions and of laser design that would enable utilization of the broad optical bands for efficient laser emission and reduced heat generation is discussed.

Lupei, V.; Lupei, A.; Gheorghe, C.; Gheorghe, L.; Achim, A. [National Institute for Lasers, Plasma and Radiation Physics, Lab. ECS, Bucharest (Romania); Ikesue, A. [World-Lab Co. Ltd., Atsuta-ku, Nagoya 456-8587 (Japan)

2012-09-15T23:59:59.000Z

306

Measurement of the solar neutrino capture rate with gallium metal. III: Results for the 2002--2007 data-taking period  

E-Print Network (OSTI)

The Russian-American experiment SAGE began to measure the solar neutrino capture rate with a target of gallium metal in Dec. 1989. Measurements have continued with only a few brief interruptions since that time. We give here the experimental improvements in SAGE since its last published data summary in Dec. 2001. Assuming the solar neutrino production rate was constant during the period of data collection, combined analysis of 168 extractions through Dec. 2007 gives a capture rate of solar neutrinos with energy more than 233 keV of 65.4 (+3.1)(-3.0) (stat) (+2.6)(-2.8) (syst) SNU. The weighted average of the results of all three Ga solar neutrino experiments, SAGE, Gallex, and GNO, is now 66.1 +/- 3.1 SNU, where statistical and systematic uncertainties have been combined in quadrature. During the recent period of data collection a new test of SAGE was made with a reactor-produced 37Ar neutrino source. The ratio of observed to calculated rates in this experiment, combined with the measured rates in the three prior 51Cr neutrino-source experiments with Ga, is 0.87 +/- 0.05. A probable explanation for this low result is that the cross section for neutrino capture by the two lowest-lying excited states in 71Ge has been overestimated. If we assume these cross sections are zero, then the standard solar model including neutrino oscillations predicts a total capture rate in Ga in the range of 63-66 SNU with an uncertainty of about 4%, in good agreement with experiment. We derive the current value of the neutrino flux produced in the Sun by the proton-proton fusion reaction to be (6.0 +/- 0.8) x 10^(10)/(cm^2 s), which agrees well with the pp flux predicted by the standard solar model. Finally, we show that the data are consistent with the assumption that the solar neutrino production rate is constant in time.

SAGE Collaboration; J. N. Abdurashitov; V. N. Gavrin; V. V. Gorbachev; P. P. Gurkina; T. V. Ibragimova; A. V. Kalikhov; N. G. Khairnasov; T. V. Knodel; I. N. Mirmov; A. A. Shikhin; E. P. Veretenkin; V. E. Yants; G. T. Zatsepin; T. J. Bowles; S. R. Elliott; W. A. Teasdale; J. S. Nico; B. T. Cleveland; J. F. Wilkerson

2009-01-15T23:59:59.000Z

307

Energy Research and Development Division FINAL PROJECT REPORT  

E-Print Network (OSTI)

FOR GALLIUM NITRIDE LIGHT EMITTING DIODE DEVICES DECEMBER 2012 CEC5002013027 Prepared for: California Nitride Light Emitting Diode Devices is the final report for the grant, PIR10055, conducted by Applied the Energy Commission at 9163271551. #12;3 ABSTRACT For light emitting diodes (LEDs) to realiz

308

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

DOE Green Energy (OSTI)

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

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

2008-01-01T23:59:59.000Z

309

Analytical and experimental evaluation of joining silicon nitride to metal and silicon carbide to metal for advanced heat engine applications  

DOE Green Energy (OSTI)

This report summarizes the results of Phase I of Analytical and Experimental Evaluation of Joining Silicon Nitride to Metal and Silicon Carbide to Metal and Silicon Carbide to Metal for Advanced Heat Engine Applications. A general methodology was developed to optimize the joint geometry and material systems for 650 and 950{degree}C applications. Failure criteria were derived to predict the fracture of the braze and ceramic. Extensive finite element analyses (FEA), using ABAQUS code, were performed to examine various joint geometries and to evaluate the affect of different interlayers on the residual stress state. Also, material systems composed of coating materials, interlayers, and braze alloys were developed for the program based on the chemical stability and strength of the joints during processing and service. Finally, the FEA results were compared with experiments using an idealized strength relationship. The results showed that the measured strength of the joint reached 30--90% of the strength by predicted by FEA. Overall results demonstrated that FEA is an effective tool for designing the geometries of ceramic-metal joints and that joining by brazing is a relevant method for advanced heat engine applications. 33 refs., 54 figs., 36 tabs.

Kang, S.; Selverian, J.H.; Kim, H.; O'Niel, D.; Kim, K. (GTE Labs., Inc., Waltham, MA (USA))

1990-04-01T23:59:59.000Z

310

Electrical transport properties of the Si-doped cubic boron nitride thin films prepared by in situ cosputtering  

SciTech Connect

Si-doped cubic boron nitride (c-BN) films with various Si concentrations were achieved by in situ cosputtering during ion beam assisted deposition. Effects of the Si concentration and rapid thermal annealing (RTA) conditions on the electrical transport properties of Si-doped c-BN thin films were investigated systematically. The results suggest that the optimum RTA condition is at the temperature of 1000 deg. C for 3 min. The resistance of Si-doped c-BN films gradually decreases as the Si concentration increases, indicating an electrical doping effect of the Si impurity. The temperature dependent electrical conductivity of the Si-doped c-BN films suggests that different conduction mechanisms are dominant over the different temperature ranges. Based on the Davis-Mott model, we propose that the extended-state conduction, band tail-state conduction and short-range hopping conduction are responsible for the respective temperature ranges. In addition, the reduction in activation energy of Si impurities is observed as the Si concentration increases.

Ying, J.; Zhang, X. W.; Yin, Z. G.; Tan, H. R.; Zhang, S. G.; Fan, Y. M. [Key Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China)

2011-01-15T23:59:59.000Z

311

Ga-Zr (Gallium - Zirconium)  

Science Conference Proceedings (OSTI)

Ga-Zr crystallographic data...Ga 5 Zr 3 44.0 oC 32 Cmcm Ga 3 Zr 2 47 oF 40 Fdd 2 βGaZr 56.7 � � αGaZr 56.7 tI 16 I 4 1 / amd Ga 4 Zr 5 62.1 hP 18 P 6 3 / mcm Ga 2 Zr 3 66 tP 10 P 4/ mbm Ga 3 Zr 5 68.6 hP 16 P 6 3 / mcm GaZr 2 72.4 tI 12 I 4/ mcm (βZr) ~94 to 100 cI 2 Im m (αZr) 99.4 to 100 hP 2 P 6 3 / mmc...

312

Ba-Ga (Barium - Gallium)  

Science Conference Proceedings (OSTI)

Ba-Ga crystallographic data...Ba-Ga crystallographic data Phase Composition, wt% Ga Pearson symbol Space group (Ba) 0 cI 2 Im m Ba 10 Ga 4.8 cF 176 Fd m Ba 8 Ga 7 30.8 cP 60 P 2 1 3 BaGa 2 50.4 hP 3 P 6/ mmm BaGa 4 67 tI 10 I 4/ mmm (Ga) 100 hP 2 P 6 3 / mmc...

313

Gallium interactions with zircaloy cladding  

Science Conference Proceedings (OSTI)

The effects of Ga from weapons-grade plutonium MOX fuel on zircaloy-IV cladding during power reactor operation have been simulated by implantations of 100 keV Ga-69 ions into a polished zircaloy-IV sample while the sample was maintained at a typical cladding temperature of 375{degrees}C. Analyses were based on scanning electron microscopy, Rutherford backscattering of 280 keV He-3 ions, and secondary ion mass spectroscopy. Subgrains at the zircaloy-IV surface formed at a Ga fluence equivalent to total release of approximately 12 ppm by weight of Ga from the fuel. The subgrains may be an intermetallic compound of Zr{sub 2}Ga. Enhanced diffusion of Ga was observed, but Ga concentrations decreased 3 orders of magnitude over a depth of 3000 {angstrom}.

Hart, R.R.; Rennie, J.; Aucoin, K.; West, M. [Texas A& M Univ., College Station, TX (United States)

1998-05-01T23:59:59.000Z

314

Novel Approaches to High-Efficiency III-V Nitride Heterostructure Emitters for Next-Generation Lighting Applications  

SciTech Connect

We report research activities and technical progress on the development of high-efficiency long wavelength ({lambda} {approx} 540nm) green light emitting diodes which covers whole years of the three-year program 'Novel approaches to high-efficiency III-V nitride heterostructure emitters for next-generation lighting applications'. The research activities were focused on the development of p-type layer that has less/no detrimental thermal annealing effect on as well as excellent structural and electrical properties and the development of green LED active region that has superior luminescence quality for {lambda}{approx}540nm green LEDs. We have also studied (1) the thermal annealing effect on blue and green LED active region during the p-type layer growth; (2) the effect of growth parameters and structural factors for LED active region on electroluminescence properties; (3) the effect of substrates and orientation on electrical and electro-optical properties of green LEDs. As a progress highlight, we obtained green-LED-active-region-friendly In{sub 0.04}Ga{sub 0.96}N:Mg exhibiting low resistivity with higher hole concentration (p=2.0 x 10{sup 18} cm{sup -3} and a low resistivity of 0.5 {omega}-cm) and improved optical quality green LED active region emitting at {approx}540nm by electroluminescence. The LEDs with p-InGaN layer can act as a quantum-confined Stark effect mitigation layer by reducing strain in the QW. We also have achieved (projected) peak IQE of {approx}25% at {lambda}{approx}530 nm and of {approx}13% at {lambda}{approx}545 nm. Visible LEDs on a non-polar substrate using (11-20) {alpha}-plane bulk substrates. The absence of quantum-confined Stark effect was confirmed but further improvement in electrical and optical properties is required.

Russell Dupuis

2007-06-30T23:59:59.000Z

315

Novel Approaches to High-Efficiency III-V Nitride Heterostructure Emitters for Next-Generation Lighting Applications  

SciTech Connect

We report research activities and technical progress on the development of high-efficiency long wavelength ({lambda} {approx} 540nm) green light emitting diodes which covers the second year of the three-year program ''Novel approaches to high-efficiency III-V nitride heterostructure emitters for next-generation lighting applications''. The second year activities were focused on the development of p-type layer that has less/no detrimental thermal annealing effect on green LED active region as well as excellent structural and electrical properties and the development of green LED active region that has superior luminescence quality for {lambda} {approx}540nm green LEDs. We have also studied the thermal annealing effect on blue and green LED active region during the p-type layer growth. As a progress highlight, we obtained green-LED-active-region-friendly In{sub 0.04}Ga{sub 0.96}N:Mg exhibiting low resistivity with higher hole concentration (p=2.0 x 10{sup 18} cm{sup -3} and a low resistivity of 0.5 {Omega}-cm) and improved optical quality green LED active region emitting at {lambda} {approx}540nm by electroluminescence. The active region of the green LEDs was found to be much more sensitive to the thermal annealing effect during the p-type layer growth than that of the blue LEDs. We have designed grown, fabricated green LED structures for both 520 nm and 540 nm for the evaluation of second year green LED development.

Russell D. Dupuis

2006-01-01T23:59:59.000Z

316

Novel Approaches to High-Efficiency III-V Nitride Heterostructure Emitters for Next-Generation Lighting Applications  

SciTech Connect

We report research activities and technical progress on the development of high-efficiency long wavelength ({lambda} {approx} 540nm) green light emitting diodes which covers whole years of the three-year program 'Novel approaches to high-efficiency III-V nitride heterostructure emitters for next-generation lighting applications'. The research activities were focused on the development of p-type layer that has less/no detrimental thermal annealing effect on as well as excellent structural and electrical properties and the development of green LED active region that has superior luminescence quality for {lambda}{approx}540nm green LEDs. We have also studied (1) the thermal annealing effect on blue and green LED active region during the p-type layer growth; (2) the effect of growth parameters and structural factors for LED active region on electroluminescence properties; (3) the effect of substrates and orientation on electrical and electro-optical properties of green LEDs. As a progress highlight, we obtained green-LED-active-region-friendly In{sub 0.04}Ga{sub 0.96}N:Mg exhibiting low resistivity with higher hole concentration (p=2.0 x 10{sup 18} cm{sup -3} and a low resistivity of 0.5 {omega}-cm) and improved optical quality green LED active region emitting at {approx}540nm by electroluminescence. The LEDs with p-InGaN layer can act as a quantum-confined Stark effect mitigation layer by reducing strain in the QW. We also have achieved (projected) peak IQE of {approx}25% at {lambda}{approx}530 nm and of {approx}13% at {lambda}{approx}545 nm. Visible LEDs on a non-polar substrate using (11-20) {alpha}-plane bulk substrates. The absence of quantum-confined Stark effect was confirmed but further improvement in electrical and optical properties is required.

Russell Dupuis

2007-06-30T23:59:59.000Z

317

Manufacturing and Performance Assessment of Stamped, Laser Welded, and Nitrided FeCrV Stainless Steel Bipolar Plates for Proton Exchange Membrane Fuel Cells  

SciTech Connect

A manufacturing and single-cell fuel cell performance study of stamped, laser welded, and gas nitrided ferritic stainless steel foils in an advanced automotive bipolar plate assembly design was performed. Two developmental foil compositions were studied: Fee20Cre4V and Fee23Cre4V wt.%. Foils 0.1 mm thick were stamped and then laser welded together to create single bipolar plate assemblies with cooling channels. The plates were then surface treated by pre-oxidation and nitridation in N2e4H2 based gas mixtures using either a conventional furnace or a short-cycle quartz lamp infrared heating system. Single-cell fuel cell testing was performed at 80 C for 500 h at 0.3 A/cm2 using 100% humidification and a 100%/40% humidification cycle that stresses the membrane and enhances release of the fluoride ion and promotes a more corrosive environment for the bipolar plates. Periodic high frequency resistance potential-current scans during the 500 h fuel cell test and posttest analysis of the membrane indicated no resistance increase of the plates and only trace levels of metal ion contamination.

Brady, Michael P [ORNL; Abdelhamid, Mahmoud [General Motors Technical Center; Dadheech, G [General Motors Technical Center; Bradley, J [General Motors Technical Center; Toops, Todd J [ORNL; Meyer III, Harry M [ORNL; Tortorelli, Peter F [ORNL

2013-01-01T23:59:59.000Z

318

Amorphous silicon/polycrystalline thin film solar cells  

DOE Patents (OSTI)

An improved photovoltaic solar cell is described including a p-type amorphous silicon layer, intrinsic amorphous silicon, and an n-type polycrystalline semiconductor such as cadmium sulfide, cadmium zinc sulfide, zinc selenide, gallium phosphide, and gallium nitride. The polycrystalline semiconductor has an energy bandgap greater than that of the amorphous silicon. The solar cell can be provided as a single-junction device or a multijunction device.

Ullal, H.S.

1991-03-13T23:59:59.000Z

319

A model of the gas-phase chemistry of boron nitride CVC from BCl{sub 3} and NH{sub 3}  

Science Conference Proceedings (OSTI)

The kinetics of gas-phase reactions occurring during the CVD of boron nitride (BN) from BCl{sub 3} and NH{sub 3} are investigated using an elementary reaction mechanism whose rate constants were obtained from theoretical predictions and literature sources. Plug-flow calculations using this mechanism predict that unimolecular decomposition of BCl{sub 3} is not significant under typical CVD conditions, but that some NH{sub 3} decomposition may occur, especially for deposition occurring at atmospheric pressure. Reaction of BCl{sub 3} with NH{sub 3} is rapid under CVD conditions and yields species containing both boron and nitrogen. One of these compounds, Cl{sub 2}BNH{sub 2}, is predicted to be a key gas-phase precursor to BN.

Allendorf, M.D.; Melius, C.F.; Osterheld, T.H.

1995-12-01T23:59:59.000Z

320

10 Nitrides: Chemistry  

Science Conference Proceedings (OSTI)

May 24, 1999 ... ant Substrates: Koen Vanhollebeke1; Ingrid Moerman1; Peter Van ...... Christine A. Wang1; Douglas C. Oakley1; 1MIT Lincoln Laboratory, ...

Note: This page contains sample records for the topic "gallium nitride ingan" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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321

Boron nitride insulating material  

DOE Patents (OSTI)

High temperature BN-insulated heaters for use as fuel pin simulators in reactor thermal hydraulic test facility studies comprise a cylindrical housing and a concentric heating element disposed within the housing and spaced apart from the housing to define an annular region therebetween. The annular region contains BN for providing electrical resistance and thermal conductivity between the housing and the heating element. The fabrication method of this invention comprises the steps of cold pressing BN powder at a pressure of 20 to 80,000 psig and a dwell time of at least 0.1-3 seconds to provide hollow cylindrical preforms of suitable dimensions for insertion into the annular region, the BN powder having a tap density of about 0.6-1.1 g/cm.sup.3 and an orientation ratio of at least about 100/3.5. The preforms are inserted into the annular region and crushed in place.

Morgan, Jr., Chester S. (Oak Ridge, TN); Cavin, O. Burl (Knoxville, TN); McCulloch, Reginald W. (Concord, TN); Clark, David L. (Clearwater, FL)

1978-01-01T23:59:59.000Z

322

Nitrided Metallic Bipolar Plates  

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

B. Cost (estimated) * Targets (2010) - resistivity < 10 mohm-cm 2 - corrosion < 1 x10 -6 Acm 2 Budget * Total project funding - cost < 5kW - 4530 K (+ 400 K Match) Team...

323

Analytical and experimental evaluation of joining silicon nitride to metal and silicon carbide to metal for advanced heat engine applications. Final report  

DOE Green Energy (OSTI)

This report summarizes the results of Phase 2 of Analytical and Experimental Evaluation of Joining Silicon Nitride to Metal and Silicon Carbide to Metal for Advanced Heat Engine Applications. A general methodology was developed to optimize the joint geometry and material systems for 650{degrees}C applications. Failure criteria were derived to predict the fracture of the braze and ceramic. Extensive finite element analyses (FEA) were performed to examine various joint geometries and to evaluate the affect of different interlayers on the residual stress state. Also, material systems composed of coating materials, interlayers, and braze alloys were developed for the program based on the chemical stability and strength of the joints during processing, and service. The FEA results were compared with experiments using two methods: (1) an idealized strength relationship of the ceramic, and (2) a probabilistic analysis of the ceramic strength (NASA CARES). The results showed that the measured strength of the joint reached 30--80% of the strength predicted by FEA. Also, potential high-temperature braze alloys were developed and evaluated for the high-temperature application of ceramic-metal joints. 38 tabs, 29 figs, 20 refs.

Kang, S.; Selverian, J.H.; O`Neil, D.; Kim, H. [GTE Labs., Inc., Waltham, MA (US)] [GTE Labs., Inc., Waltham, MA (US); Kim, K. [Brown Univ., Providence, RI (US). Div. of Engineering] [Brown Univ., Providence, RI (US). Div. of Engineering

1993-05-01T23:59:59.000Z

324

Gallium composition dependence of crystallographic and thermoelectric properties in polycrystalline type-I Ba{sub 8}Ga{sub x}Si{sub 46-x} (nominal x=14-18) clathrates prepared by combining arc melting and spark plasma sintering methods  

SciTech Connect

The gallium composition dependence of crystallographic and thermoelectric properties in polycrystalline n-type Ba{sub 8}Ga{sub x}Si{sub 46-x} (nominal x=14-18) compounds with the type-I clathrate structure is presented. Samples were prepared by combining arc melting and spark plasma sintering methods. Powder x-ray diffraction, Rietveld analysis, scanning electron microscopy, and energy-dispersive x-ray spectroscopy show that the solubility limit of gallium in the type-I clathrate phase is close to x=15, which is slightly higher than that for a single crystal. The carrier concentration at room temperature decreases from 2 Multiplication-Sign 10{sup 21} cm{sup -3} to 4 Multiplication-Sign 10{sup 20} cm{sup -3} as the Ga content x increases. The Seebeck coefficient, the electrical conductivity, and the thermal conductivity vary systematically with the carrier concentration when the Ga content x varies. The effective mass (2.0m{sub 0}), the carrier mobility (10 cm{sup 2} V{sup -1} s{sup -1}), and the lattice thermal conductivity (1.1 W m{sup -1} K{sup -1}) are determined for the Ga content x=14.51. The dimensionless thermoelectric figure of merit ZT is about 0.55 at 900 K for the Ga content x=14.51. The calculation of ZT using the experimentally determined material parameters predicts ZT=0.8 (900 K) at the optimum carrier concentration of about 2 Multiplication-Sign 10{sup 20} cm{sup -3}. - Graphical abstract: The gallium composition dependence of crystallographic and thermoelectric properties is presented on polycrystalline n-type Ba{sub 8}Ga{sub x}Si{sub 46-x} with the type-I clathrate structure prepared by combining arc melting and spark plasma sintering methods. The thermoelectric figure of merit ZT reaches 0.55 at 900 K due to the increase in the Ga content (close to x=15), and a calculation predicts further improvement of ZT at the optimized carrier concentration. Highlights: Black-Right-Pointing-Pointer Crystallographic properties of Ba{sub 8}Ga{sub x}Si{sub 46-x} clathrates are characterized. Black-Right-Pointing-Pointer Arc melting and spark plasma sintering process enables increase of Ga content. Black-Right-Pointing-Pointer We elucidate the Ga composition dependence of thermoelectric properties. Black-Right-Pointing-Pointer Thermoelectric figure of merit ZT is improved due to the increased Ga content. Black-Right-Pointing-Pointer Calculation predicts a potential ZT=0.8 at 900 K at optimized carrier concentration.

Anno, Hiroaki, E-mail: anno@rs.tus.ac.jp [Department of Electrical Engineering, Faculty of Engineering, Tokyo University of Science, Yamaguchi, 1-1-1 Daigaku-Dori, Sanyoonoda 756-0884 (Japan) [Department of Electrical Engineering, Faculty of Engineering, Tokyo University of Science, Yamaguchi, 1-1-1 Daigaku-Dori, Sanyoonoda 756-0884 (Japan); JST, CREST, 5 Sanbancho, Chiyoda-ku, Tokyo 102-0075 (Japan); Yamada, Hiroki; Nakabayashi, Takahiro; Hokazono, Masahiro [Department of Electrical Engineering, Faculty of Engineering, Tokyo University of Science, Yamaguchi, 1-1-1 Daigaku-Dori, Sanyoonoda 756-0884 (Japan)] [Department of Electrical Engineering, Faculty of Engineering, Tokyo University of Science, Yamaguchi, 1-1-1 Daigaku-Dori, Sanyoonoda 756-0884 (Japan); Shirataki, Ritsuko [Department of Electrical Engineering, Faculty of Engineering, Tokyo University of Science, Yamaguchi, 1-1-1 Daigaku-Dori, Sanyoonoda 756-0884 (Japan) [Department of Electrical Engineering, Faculty of Engineering, Tokyo University of Science, Yamaguchi, 1-1-1 Daigaku-Dori, Sanyoonoda 756-0884 (Japan); JST, CREST, 5 Sanbancho, Chiyoda-ku, Tokyo 102-0075 (Japan)

2012-09-15T23:59:59.000Z

325

Not Your Grandma's Quilt Researchers develop technique to keep cool high-power semiconductor  

E-Print Network (OSTI)

devices used in wireless applications, traffic lights and electric cars By Sean Nealon On MAY 8, 2012 in everything from traffic lights to electric cars. Gallium Nitride (GaN), a semiconductor material found by the Nano-Device Laboratory research group led byAlexander Balandin, professor of electrical engineering

326

Naval Postgraduate School Monterey, California 939435138  

E-Print Network (OSTI)

..............................................................................................................9 The Art of the Deal: How Can the Air Force Successfully Execute Renewable Energy Transactions of an Incident High-Energy Electromagnetic Beam ....21 Fusion Centers: Securing America's Homeland from Threats of an Incident High-Energy Electromagnetic Beam ... 23 Near-Field Imaging of Charge Transport in Gallium Nitride

327

Photonic-crystal GaN light-emitting diodes with tailored guided modes distribution  

E-Print Network (OSTI)

Photonic-crystal GaN light-emitting diodes with tailored guided modes distribution Aurélien David of photonic crystal PhC -assisted gallium nitride light-emitting diodes LEDs to the existence of unextracted a promising but challenging solution towards efficient solid-state lighting. Conventional GaN-based light-emitting

Recanati, Catherine

328

Iron-Nitride-Based Magnets: Synthesis and Phase Stabilization of Body Center Tetragonal (BCT) Metastable Fe-N Anisotropic Nanocomposite Magnet- A Path to Fabricate Rare Earth Free Magnet  

SciTech Connect

REACT Project: The University of Minnesota will develop an early stage prototype of an iron-nitride permanent magnet material for EVs and renewable power generators. This new material, comprised entirely of low-cost and abundant resources, has the potential to demonstrate the highest energy potential of any magnet to date. This project will provide the basis for an entirely new class of rare-earth-free magnets capable of generating power without costly and scarce rare earth materials. The ultimate goal of this project is to demonstrate a prototype with magnetic properties exceeding state-of-the-art commercial magnets.

None

2012-01-01T23:59:59.000Z

329

Commercialization of New Lattice-Matched Multi-Junction Solar Cells Based on Dilute Nitrides: July 8, 2010 - March 7, 2012  

SciTech Connect

Final Technical Progress Report for PV Incubator subcontract NAT-0-99013-03. The overall objective of this Incubator subcontract was to complete the work necessary to make commercial ready solar cells using the dilute nitride technology. The specific objectives of this program were aimed at completing the development of a triple-junction solar cell that incorporates a GaInNAs {approx}1eV subcell to the point of commercial readiness, and determining the cell reliability and, if necessary, identifying and eliminating process or material related issues that lead to early-life cell failures. There were three major objectives for Phase 1, each of which focuses on a key element of the solar cell that determines its performance in a commercial CPV system. One objective was to optimize the quality and performance of the key individual components making up the solar cell structure and then to optimize the integration of these components into a complete triple-junction cell. A second objective was to design and test anti-reflective coating that maximizes the light coupled into a 3J cell with a {approx}1 eV bottom cell bandgap. The third objective was to develop Highly Accelerated Life Tests (HALT) protocols and tools for identifying and correcting potential reliability problems. The Phase 2 objectives were a continuation of the work begun in Phase 1 but aimed at optimizing cell performance for commercial requirements. Phase 2 had four primary objectives: (1) develop a glass-matched anti-reflective coating (ARC) and optimize the cell/ARC to give good performance at 60C operating temperature, (2) optimize the cell for good operation at 60C and high concentration, and (3) complete the light biased HALT system and use it to determine what, if any, failures are observed, and (4) determine the reliability limits of the optimized cell.

Herb, J.

2012-04-01T23:59:59.000Z

330

Effects of Rare Earth (RE) Intergranular Adsorption on the Phase Transformation and Microstructure Evolution in Silicon Nitride with RE2O3 + MgO Additives: Fracture Behavior  

SciTech Connect

Silicon nitride powders consist primarily of the alpha phase, which transforms to the beta phase during the densification and microstructural evolution of Si3N4 ceramics. The temperature at which the transformation initiates in the presence of a combination of MgO and RE2O3 densification additives is found to decrease with increasing atomic number of the rare earth (RE). This trend coincides with the predicted and observed decrease in the affinity of the rare earth to segregate to and absorb on the prism planes of hexagonal prism shaped beta grains with increase in the atomic number of the RE. When RE adsorption is diminished, Si (and N) attachment on the smooth prism planes is enhanced, which increases diametrical growth rates, normally reaction-rate limited by an attachment mechanism. Combined with the typically fast [0001] growth, it is this augmented grain growth that contributes towards the initiation of the alpha-beta transformation at lower temperatures. With the enhanced transformation, observations reveal an increase in the number of beta grains growing in the early stages of densification. On the other hand, increased RE adsorption leads to greater growth anisotropy resulting in the formation of higher aspect ratio grains. Thus, Lu2O3 generates larger diameter, yet elongated, reinforcing grains, while La2O3 results in reinforcing grains of higher aspect ratio. The Gd2O3 additive transformation and microstructual characteristics lie intermediate to those of the lanthanide end member elements. Despite these differences, a substantial fraction of large reinforcing grains were found for each additive composition. As a result, the mechanical properties of the resultant ceramics are similar with flexure strengths in excess of 1 GPa, fracture toughness values greater than 10 MPa m1/2 at room temperature and excellent strength retention (>800 MPa) at 1200 C.

Becher, Paul F [ORNL; Painter, Gayle S [ORNL; Shibata, Naoya [University of Tokyo, Tokyo, Japan; Waters, Shirley B [ORNL; Lin, Hua-Tay [ORNL

2008-01-01T23:59:59.000Z

331

GALLIUM ARSENIDE SEMICONDUCTOR-BASED NEUTRON DETECTOR  

NEUTRON DETECTOR BENEFITS Portable, ... High Flux Isotope Reactor and Spallation Neutron Source. Several Homeland Security. LINKS TO ONLINE ...

332

References and Notes for Gallium ( Ga )  

Science Conference Proceedings (OSTI)

... Res. Natl. Bur. Stand. (US) 48, 334 (1952). ND82, JHM Neijzen and A. Donszelmann, Physica 114C, 241 (1982). The stated ...

333

Formation of manganese {delta}-doped atomic layer in wurtzite GaN  

Science Conference Proceedings (OSTI)

We describe the formation of a {delta}-doped manganese layer embedded within c-plane wurtzite gallium nitride using a special molecular beam epitaxy growth process. Manganese is first deposited on the gallium-poor GaN (0001) surface, forming a {radical}(3) Multiplication-Sign {radical}(3)-R30 Degree-Sign reconstructed phase. This well-defined surface reconstruction is then nitrided using plasma nitridation, and gallium nitride is overgrown. The manganese content of the {radical}(3) Multiplication-Sign {radical}(3)-R30 Degree-Sign phase, namely one Mn per each {radical}(3) Multiplication-Sign {radical}(3)-R30 Degree-Sign unit cell, implies that the MnGaN alloy layer has a Mn concentration of up to 33%. The structure and chemical content of the surface are monitored beginning from the initial growth stage up through the overgrowth of 20 additional monolayers (MLs) of GaN. An exponential-like drop-off of the Mn signal with increasing GaN monolayers, as measured by Auger electron spectroscopy, indicates that the highly concentrated Mn layer remains at the {delta}-doped interface. A model of the resultant {delta}-doped structure is formulated based on the experimental data, and implications for possible spintronic applications are discussed.

Shi Meng; Chinchore, Abhijit; Wang Kangkang; Mandru, Andrada-Oana; Liu Yinghao; Smith, Arthur R. [Department of Physics and Astronomy, Nanoscale and Quantum Phenomena Institute, Ohio University, Athens, Ohio 45701 (United States)

2012-09-01T23:59:59.000Z

334

Possibility of Electron Beam Damage on the InGaN well Layers of ...  

Science Conference Proceedings (OSTI)

Contributions of Atom Probe Tomography to the Understanding of Steels · Control of p-n ... Relationships in a Series of Co-Cr-Cu-Fe-Ni-Al High Entropy Alloys.

335

K2, Photoluminescence of Bandgap-Graded InGaN Wires Grown by ...  

Science Conference Proceedings (OSTI)

I4, Electrical Spin Injection in a Hybrid Organic/Inorganic Spin-Polarized Light Emitting Diode (Spin-LED) · I5, Properties of MnAs/GaMnAs/MnAs Magnetic ...

336

The Fluctuation of In Composition in InGaN Based LED Investigated ...  

Science Conference Proceedings (OSTI)

Design of Pre-Weakening and Evaluation of Structural Safety for Explosive ... Crystallization Temperature of Pd-Cu-Si System Using Integrated Thin Film Samples ... Mechanical Properties of 5083 Aluminium Welds after Manual and Automatic ...

337

II5, Electrical Tuning of InGaN Quantum Dots in GaN Photonic ...  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, 2011 Electronic Materials Conference. Symposium, 2011 Electronic Materials Conference. Presentation Title, II5, Electrical Tuning ...

338

Growth of InGaN HBTs by MOCVD THEODORE CHUNG,1,5  

E-Print Network (OSTI)

. Trimethylgallium (TMGa), trimethylindium (TMIn), and ammonia (NH3) are used as the sour- ces, while disilane (Si2H6

Asbeck, Peter M.

339

Electroluminescense from InGaN Quantum Dots, in a Monolithically ...  

Science Conference Proceedings (OSTI)

We present an electrically driven structure based on a monolithically GaN/AlInN cavity with a single quantum dot layer grown by MOVPE. The device was grown ...

340

LATE NEWS: L7, Molecular Beam Epitaxy of N-Polar InGaN  

Science Conference Proceedings (OSTI)

L6, PECVD-SiN, Si or Si/Al2O3-Capped ED-Mode AlN/GaN Inverters · Hide details for [

Note: This page contains sample records for the topic "gallium nitride ingan" 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

Synthesis and characterization of GaN thin films deposited on different substrates using a low-cost electrochemical deposition technique  

Science Conference Proceedings (OSTI)

Gallium nitride GaN thin films were deposited on three different substrates; Si (111), Si (100) and ITO coated glass using electrochemical deposition technique at 20 Degree-Sign C. A mixture of gallium nitrate, ammonium nitrate was used as electrolyte. The deposited films were investigated at room temperature by a series of material characterization techniques, namely; scanning electron microscopy (SEM), EDX and X-ray diffraction (XRD). SEM images and EDX results indicated that the growth of GaN films varies according to the substrates. XRD analyses showed the presence of hexagonal wurtzite and cubic zinc blende GaN phases with the crystallite size around 18-29 nm.

Al-Heuseen, K.; Hashim, M. R. [Al-Balqa Applied University, Ajloun University College (Jordan); School of Physics, Universiti Sains Malaysia, 11800-Penang (Malaysia)

2012-09-06T23:59:59.000Z

342

Final LDRD report : design and fabrication of advanced device structures for ultra high efficiency solid state lighting.  

SciTech Connect

The goal of this one year LDRD was to improve the overall efficiency of InGaN LEDs by improving the extraction of light from the semiconductor chip. InGaN LEDs are currently the most promising technology for producing high efficiency blue and green semiconductor light emitters. Improving the efficiency of InGaN LEDs will enable a more rapid adoption of semiconductor based lighting. In this LDRD, we proposed to develop photonic structures to improve light extraction from nitride-based light emitting diodes (LEDs). While many advanced device geometries were considered for this work, we focused on the use of a photonic crystal for improved light extraction. Although resonant cavity LEDs and other advanced structures certainly have the potential to improve light extraction, the photonic crystal approach showed the most promise in the early stages of this short program. The photonic crystal (PX)-LED developed here incorporates a two dimensional photonic crystal, or photonic lattice, into a nitride-based LED. The dimensions of the photonic crystal are selected such that there are very few or no optical modes in the plane of the LED ('lateral' modes). This will reduce or eliminate any radiation in the lateral direction so that the majority of the LED radiation will be in vertical modes that escape the semiconductor, which will improve the light-extraction efficiency. PX-LEDs were fabricated using a range of hole diameters and lattice constants and compared to control LEDs without a photonic crystal. The far field patterns from the PX-LEDs were dramatically modified by the presence of the photonic crystal. An increase in LED brightness of 1.75X was observed for light measured into a 40 degree emission cone with a total increase in power of 1.5X for an unencapsulated LED.

Koleske, Daniel David; Bogart, Katherine Huderle Andersen; Shul, Randy John; Wendt, Joel Robert; Crawford, Mary Hagerott; Allerman, Andrew Alan; Fischer, Arthur Joseph

2005-04-01T23:59:59.000Z

343

CX-000845: Categorical Exclusion Determination | Department of Energy  

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

0845: Categorical Exclusion Determination 0845: Categorical Exclusion Determination CX-000845: Categorical Exclusion Determination 25A2445 - Ammonothermal Bulk Gallium Nitride (GaN) Crystal Growth for Energy Efficient Lighting CX(s) Applied: B3.6 Date: 01/15/2010 Location(s): New York Office(s): Advanced Research Projects Agency - Energy This project plans to address the vast energy loss and consumption associated with conventional lighting by developing a new route to large, high-quality, single crystals of gallium nitride. These crystals will serve as substrates for light emitting diodes offering high-efficiency lighting. DOCUMENT(S) AVAILABLE FOR DOWNLOAD CX-000845.pdf More Documents & Publications CX-009889: Categorical Exclusion Determination Power Electronics Research and Development Program Plan

344

Page not found | Department of Energy  

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

31 - 9940 of 29,416 results. 31 - 9940 of 29,416 results. Download CX-010893: Categorical Exclusion Determination Modification to Demolish Building 900A and Reconstruct Building 900 Project CX(s) Applied: B1.3, B1.15 Date: 06/28/2013 Location(s): Pennsylvania Offices(s): National Energy Technology Laboratory http://energy.gov/nepa/downloads/cx-010893-categorical-exclusion-determination Download CX-010894: Categorical Exclusion Determination Graphene-Based Composite Sensor for Energy Applications CX(s) Applied: B3.6 Date: 06/27/2013 Location(s): West Virginia Offices(s): National Energy Technology Laboratory http://energy.gov/nepa/downloads/cx-010894-categorical-exclusion-determination Download CX-010895: Categorical Exclusion Determination Development and Industrialization of Indium Gallium Nitride/Gallium Nitride

345

Transphorm Takes Energy Efficiency to a New Level | Department of Energy  

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

Transphorm Takes Energy Efficiency to a New Level Transphorm Takes Energy Efficiency to a New Level Transphorm Takes Energy Efficiency to a New Level February 24, 2012 - 1:20pm Addthis Transphorm's gallium nitride semiconductors could be used to make operating photovoltaic panels, like these on the roof of the Research Support Facility, motor drives and transistors more energy efficient. | Photo courtesy of National Renewable Energy Laboratory. Transphorm's gallium nitride semiconductors could be used to make operating photovoltaic panels, like these on the roof of the Research Support Facility, motor drives and transistors more energy efficient. | Photo courtesy of National Renewable Energy Laboratory. Michael Hess Michael Hess Former Digital Communications Specialist, Office of Public Affairs What are the key facts?

346

Page not found | Department of Energy  

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

71 - 13680 of 26,764 results. 71 - 13680 of 26,764 results. Download CX-010895: Categorical Exclusion Determination Development and Industrialization of Indium Gallium Nitride/Gallium Nitride (InGaN/GaN) Light Emitting Diodes LEDs on Patterned Sapphire Substrate (PSS) for Low Cost Emitter Architecture CX(s) Applied: B3.6 Date: 06/27/2013 Location(s): California Offices(s): National Energy Technology Laboratory http://energy.gov/nepa/downloads/cx-010895-categorical-exclusion-determination Download CX-010896: Categorical Exclusion Determination California Low Carbon Fuels Infrastructure Investment Initiative (SUMMARY Categorical Exclusion) CX(s) Applied: B5.22 Date: 06/27/2013 Location(s): California Offices(s): National Energy Technology Laboratory http://energy.gov/nepa/downloads/cx-010896-categorical-exclusion-determination

347

Categorical Exclusion Determinations: Massachusetts | Department of Energy  

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

1 1 CX-006559: Categorical Exclusion Determination Dedham Municipal Solar Project CX(s) Applied: A9, B5.1 Date: 08/22/2011 Location(s): Dedham, Massachusetts Office(s): Energy Efficiency and Renewable Energy, Golden Field Office August 17, 2011 CX-006556: Categorical Exclusion Determination Gallium Nitride Electronics for Grid Applications CX(s) Applied: A1, A2, A9, A11, B3.6 Date: 08/17/2011 Location(s): Cambridge, Massachusetts Office(s): Electricity Delivery and Energy Reliability, National Energy Technology Laboratory August 17, 2011 CX-006555: Categorical Exclusion Determination Gallium Nitride Electronics for Grid Applications CX(s) Applied: A1, A2, A9, A11, B3.6 Date: 08/17/2011 Location(s): Lexington, Massachusetts Office(s): Electricity Delivery and Energy Reliability, National Energy

348

Categorical Exclusion Determinations: Arkansas | Department of Energy  

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

Arkansas Arkansas Categorical Exclusion Determinations: Arkansas Location Categorical Exclusion Determinations issued for actions in Arkansas. DOCUMENTS AVAILABLE FOR DOWNLOAD September 16, 2013 CX-010974: Categorical Exclusion Determination Advanced Low-Cost Silicon Carbide (SiC) and Gallium Nitride (GaN) Wide Bandgap Inverters for Under-the-Hood Electric Vehicle Traction... CX(s) Applied: B3.6 Date: 09/16/2013 Location(s): Arkansas Offices(s): National Energy Technology Laboratory September 16, 2013 CX-010973: Categorical Exclusion Determination Advanced Low-Cost Silicon Carbide (SiC) and Gallium Nitride (GaN) Wide Bandgap Inverters for Under-the-Hood Electric Vehicle Traction... CX(s) Applied: B3.6 Date: 09/16/2013 Location(s): Arkansas Offices(s): National Energy Technology Laboratory

349

Transphorm Takes Energy Efficiency to a New Level | Department of Energy  

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

Transphorm Takes Energy Efficiency to a New Level Transphorm Takes Energy Efficiency to a New Level Transphorm Takes Energy Efficiency to a New Level February 24, 2012 - 1:20pm Addthis Transphorm's gallium nitride semiconductors could be used to make operating photovoltaic panels, like these on the roof of the Research Support Facility, motor drives and transistors more energy efficient. | Photo courtesy of National Renewable Energy Laboratory. Transphorm's gallium nitride semiconductors could be used to make operating photovoltaic panels, like these on the roof of the Research Support Facility, motor drives and transistors more energy efficient. | Photo courtesy of National Renewable Energy Laboratory. Michael Hess Michael Hess Former Digital Communications Specialist, Office of Public Affairs What are the key facts?

350

Categorical Exclusion Determinations: A9 | Department of Energy  

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

August 17, 2011 August 17, 2011 CX-006556: Categorical Exclusion Determination Gallium Nitride Electronics for Grid Applications CX(s) Applied: A1, A2, A9, A11, B3.6 Date: 08/17/2011 Location(s): Cambridge, Massachusetts Office(s): Electricity Delivery and Energy Reliability, National Energy Technology Laboratory August 17, 2011 CX-006555: Categorical Exclusion Determination Gallium Nitride Electronics for Grid Applications CX(s) Applied: A1, A2, A9, A11, B3.6 Date: 08/17/2011 Location(s): Lexington, Massachusetts Office(s): Electricity Delivery and Energy Reliability, National Energy Technology Laboratory August 16, 2011 CX-006538: Categorical Exclusion Determination Bringing Hydrogen Fuel Cell Systems into Green Communities - University Retirement Center at Davis Green Energy Community

351

Peering into a Quantum Well | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

Peering into a Quantum Well Peering into a Quantum Well Discovery & Innovation Stories of Discovery & Innovation Brief Science Highlights SBIR/STTR Highlights Contact Information Office of Science U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5430 09.01.11 Peering into a Quantum Well Supercomputer simulation illuminates mysterious "droop" in solid-state lighting. Print Text Size: A A A Subscribe FeedbackShare Page Gallium nitride light-emitting diode. Image courtesy of Lawrence Berkeley National Laboratory Gallium nitride light-emitting diode. Despite being cool, ultra-efficient, and long-lasting, solid-state lighting has yet to conquer the general lighting market partly due to a problem called "efficiency droop." New findings from simulations carried out at

352

Page not found | Department of Energy  

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

71 - 13980 of 28,560 results. 71 - 13980 of 28,560 results. Download CX-010894: Categorical Exclusion Determination Graphene-Based Composite Sensor for Energy Applications CX(s) Applied: B3.6 Date: 06/27/2013 Location(s): West Virginia Offices(s): National Energy Technology Laboratory http://energy.gov/nepa/downloads/cx-010894-categorical-exclusion-determination Download CX-010895: Categorical Exclusion Determination Development and Industrialization of Indium Gallium Nitride/Gallium Nitride (InGaN/GaN) Light Emitting Diodes LEDs on Patterned Sapphire Substrate (PSS) for Low Cost Emitter Architecture CX(s) Applied: B3.6 Date: 06/27/2013 Location(s): California Offices(s): National Energy Technology Laboratory http://energy.gov/nepa/downloads/cx-010895-categorical-exclusion-determination

353

Effective passivation of the low resistivity silicon surface by a rapid thermal oxide/PECVD silicon nitride stack and its application to passivated rear and bifacial Si solar cells  

DOE Green Energy (OSTI)

A novel stack passivation scheme, in which plasma silicon nitride (SiN) is stacked on top of a rapid thermal SiO{sub 2} (RTO) layer, is developed to attain a surface recombination velocity (S) approaching 10 cm/s at the 1.3 {Omega}-cm p-type (100) silicon surface. Such low S is achieved by the stack even when the RTO and SiN films individually yield considerably poorer surface passivation. Critical to achieving low S by the stack is the use of a short, moderate temperature anneal (in this study 730 C for 30 seconds) after film growth and deposition. This anneal is believed to enhance the release and delivery of atomic hydrogen from the SiN film to the Si-SiO{sub 2} interface, thereby reducing the density of interface traps at the surface. Compatibility with this post-deposition anneal makes the stack passivation scheme attractive for cost-effective solar cell production since a similar anneal is required to fire screen-printed contacts. Application of the stack to passivated rear screen-printed solar cells has resulted in V{sub oc}`s of 641 mV and 633 mV on 0.65 {Omega}-cm and 1.3 {Omega}-cm FZ Si substrates, respectively. These V{sub oc} values are roughly 20 mV higher than for cells with untreated, highly recombinative back surfaces. The stack passivation has also been used to form fully screen-printed bifacial solar cells which exhibit rear-illuminated efficiency as high as 11.6% with a single layer AR coating.

Rohatgi, A.; Narasimha, S. [Georgia Inst. of Tech., Atlanta, GA (United States). Univ. Center for Excellence in Photovoltaics Research and Education; Ruby, D.S. [Sandia National Labs., Albuquerque, NM (United States)

1998-08-01T23:59:59.000Z

354

SYNTHESIS OF HIGH-PURITY BULK COPPER INDIUM GALLIUM SELENIDE ...  

A sputtering target formed by the method can have an oxygen content of 10 ppm by weight, ... Biomass and Biofuels; Building Energy Efficiency; Electricity Transmission;

355

Monolithic series-connected gallium arsenide converter development  

DOE Green Energy (OSTI)

We report the development of monolithic GaAs photovoltaic devices intended to convert light generated by a laser or other bright source to electricity. The converters described here can provide higher operating voltage than is possible using a single-junction converter, owing to use of a monolithic circuit that forms a planar series-connected string of single-junction sub-cells. This planar monolithic circuit is arranged to deliver the desired voltage and current during operation at the maximum power point. The paper describes two-, six-, and twelve-junction converters intended for illumination by a laser diode with a wavelength of 0.8 {mu}m. Design and characterization data are presented for optical power in the range of 100 mW to 1 W. The best conversion efficiency exceeds 50%. 9 refs., 4 figs., 2 tabs.

Spitzer, M.B.; McClelland, R.W.; Dingle, B.D.; Dingle, J.E.; Hill, D.S. (Kopin Corp., Taunton, MA (United States)); Rose, B.H. (Sandia National Labs., Albuquerque, NM (United States))

1991-01-01T23:59:59.000Z

356

Superconductivity in gallium-substituted Ba8Si46 clathrates  

E-Print Network (OSTI)

We report a joint experimental and theoretical investigation of superconductivity in Ga-substituted type-I silicon clathrates. We prepared samples of the general formula Ba8Si46-xGax, with different values of x. We show that Ba8Si40Ga6 is a bulk superconductor, with an onset at T-C approximate to 3.3 K. For x=10 and higher, no superconductivity was observed down to T=1.8 K. This represents a strong suppression of superconductivity with increasing Ga content, compared to Ba8Si46 with T-C approximate to 8 K. Suppression of superconductivity can be attributed primarily to a decrease in the density of states at the Fermi level, caused by a reduced integrity of the sp(3)-hybridized networks as well as the lowering of carrier concentration. These results are corroborated by first-principles calculations, which show that Ga substitution results in a large decrease of the electronic density of states at the Fermi level, which explains the decreased superconducting critical temperature within the BCS framework. To further characterize the superconducting state, we carried out magnetic measurements showing Ba8Si40Ga6 to be a type-II superconductor. The critical magnetic fields were measured to be H-C1 approximate to 35 Oe and H-C2 approximate to 8.5 kOe. We deduce the London penetration depth lambda approximate to 3700 A and the coherence length xi(c)approximate to 200 A. Our estimate of the electron-phonon coupling reveals that Ba8Si40Ga6 is a moderate phonon-mediated BCS superconductor.

Li, Yang; Zhang, Ruihong; Liu, Yang; Chen, Ning; Luo, Z. P.; Ma, Xingqiao; Cao, Guohui; Feng, Z. S.; Hu, Chia-Ren; Ross, Joseph H., Jr.

2007-01-01T23:59:59.000Z

357

Rutherford backscattering analysis of gallium implanted 316 stainless steel  

E-Print Network (OSTI)

Ion implantation of Ga ions into 316 stainless steel was performed at fluences ranging from 8x10ą? to 10ą? ions/cm˛. The depth profile of Ga in the steel was analyzed via Rutherford Backscattering and ToFSIMS. The surface effects were characterized with SEM analysis. Results indicate that Ga saturation was reached at fluences between 2-6x10ą? ions/cm˛. The maximum Ga concentration occurred near the surface and was between 20 and 25 atomic percent. A constant Ga concentration of 5% was attained at 300 [] and deeper. The possible enhanced diffusion of Ga was observed, but not necessarily through the grain boundaries. Although there was no indication of compound formation, significant pitting was observed at high fluences. Repassivation characteristics of stainless steel may be inhibited at high fluences; therefore future studies are recommended.

Ortensi, Javier

2000-01-01T23:59:59.000Z

358

Supply Chain Dynamics of Tellurium (Te), Indium (In), and Gallium...  

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

CdTe Solar Cells, Solar Energy Materials and Solar Cells, 90 (2006) 2263-2271. 3 CRC Handbook of Chemistry and Physics, CRC Press, Boca Raton, FL, 1986. 4 M.A. Green, K....

359

Session B: Gallium Arsenide Processing Room: University Center ...  

Science Conference Proceedings (OSTI)

We report thin film InP based resonant tunneling diodes (RTD) and tunneling hot electron transfer amplifiers (THETA) contact bonded to silicon substates.

360

Polarization engineering via staggered InGaN quantum wells for radiative efficiency enhancement of light emitting diodes  

E-Print Network (OSTI)

of light emitting diodes Ronald A. Arif, Yik-Khoon Ee, and Nelson Tansu Citation: Appl. Phys. Lett. 91 extraction in GaN-based light emitting diodes Appl. Phys. Lett. 100, 061107 (2012) Electrically driven nanopyramid green light emitting diode Appl. Phys. Lett. 100, 061106 (2012) Ultraviolet electroluminescence

Gilchrist, James F.

Note: This page contains sample records for the topic "gallium nitride ingan" from the National Library of EnergyBeta (NLEBeta).
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361

Improving light output power of InGaN-based light emitting diodes with pattern-nanoporous p-type GaN:Mg surfaces  

SciTech Connect

InGaN-based light emitting diodes (LEDs) with a top pattern-nanoporous p-type GaN:Mg surface were fabricated by using a photoelectrochemical (PEC) process. The peak wavelengths of electroluminescence (EL) and operating voltages were measured as 461.2 nm (3.1 V), 459.6 nm (9.2 V), and 460.1 nm (3.3 V) for conventional, nanoporous, and pattern-nanoporous LEDs using 20 mA operation current. The EL spectrum of the nanoporous LED had a larger blueshift phenomenon as a result of a partial compression strain release in the InGaN active layer through the formation of a top nanoporous surface. The light output power had 12.1% and 26.4% enhancements for the nanoporous and the pattern-nanoporous LEDs compared with conventional LEDs. The larger operating voltage of the nanoporous LED was due to the non-ohmic contact on the PEC treated p-type GaN:Mg surface. By using a pattern-nanoporous p-type GaN:Mg structure, the operating voltage of the pattern-nanoporous LED was reduced to 3.3 V. A lower compression strain in the InGaN active layer and a higher light extraction efficiency at the top nanoporous surface were observed in pattern-nanoporous LEDs for higher efficiency nitride-based LED applications.

Yang, C.C.; Lin, C.F.; Lin, C.M.; Chang, C.C.; Chen, K.T.; Chien, J.F.; Chang, C.Y. [Department of Materials Engineering, National Chung Hsing University, Taichung 402, Taiwan (China)

2008-11-17T23:59:59.000Z

362

Session K: III-Nitride Nanowires  

Science Conference Proceedings (OSTI)

Jun 23, 2010 ... The EDX data in conjunction with scanning transmission electron ... shifted to the red until narrow emission lines appeared around 371nm. ... 1National Institute of Standards and Technology (NIST); 2University of Colorado .... Interestingly the average nanowire diameter frequently differed from one "row" of ...

363

Silicon Nitride Nanowire Papers Synthesized by Silica ...  

Science Conference Proceedings (OSTI)

Aerosol Jet® Material Deposition for High Resolution Printed Electronic Applications ... Carbon Nanotube Coatings Laser Power and Energy Measurements ... Rational Tailoring of 1-D (Nanowires), 2-D (Graphene) and 3-D (Ceramic/Carbon ...

364

Session Q: III-Nitrides: Electronics II  

Science Conference Proceedings (OSTI)

Jun 23, 2011... base stations and switches in power conditioning applications. ..... that the current is caused by tunneling through dislocations in the space ...

365

Amine-functionalized boron nitride nanotubes  

or posting on open internet sites, your personal or institution’s website or repository, are prohibited. For exceptions, permission

366

Session A: III-Nitrides: MBE Growth  

Science Conference Proceedings (OSTI)

Jun 22, 2011... Jiao1; Wei Kong1; Tongho Kim1; April Brown1; 1Duke University .... Hall measurements seem to show that the activation energy is lower the ...

367

Boron Nitride Nanotube Reinforced Aluminum Nanocomposites  

Science Conference Proceedings (OSTI)

Nanocomposites for Electrochemical Energy Storage ... Thermoelectric Study of InGaN-Based Materials for Thermal Energy Harvesting · Thick and Thin Film ...

368

Session KK: Indium Nitride - Programmaster.org  

Science Conference Proceedings (OSTI)

Jun 25, 2010 ... PL spectra clearly demonstrate two peaks: at 0.678eV due to InN ... Kamimura1; Katsumi Kishino1; Akihiko Kikuchi1; 1Sophia University

369

Amine-functionalized boron nitride nanotubes  

bDepartment of Physics, University of California, Berkeley, CA 94720, USA cDepartment of Chemistry, University of California, Berkeley, CA 94720, USA

370

Superhydrophobicity of Boron Nitride Nanotubes Structures  

Science Conference Proceedings (OSTI)

... demonstrate superhydrophobicity in both air environment and oil phase. ... Application of Biomass Waste Materials in the Nano Mineral Synthesis .... Nanocomposites by Laser Power Variation Throughout the Laser Pyrolysis Process.

371

Direct Aluminum Powder Nitridation under Flowing Ammonia  

Science Conference Proceedings (OSTI)

Design and Manufacture of Fluidized Bed Reactor in Pilot Scale for Multiple ..... The Effect of Circulating Coal Slurry Water Hardness on Coal Preparation.

372

Available Technologies: Boron Nitride Converted Carbon Fibers  

Energy Efficiency; Energy Storage and Recovery; Renewable Energy; Environmental Technologies. Monitoring and Imaging; Remediation; Modeling; Imaging ...

373

Cl{sub 2}-based dry etching of the AlGaInN system in inductively coupled plasmas  

DOE Green Energy (OSTI)

Cl{sub 2}-based Inductively Coupled Plasmas with low additional dc self- biases(-100V) produce convenient etch rates(500-1500 A /min) for GaN, AlN, InN, InAlN and InGaN. A systematic study of the effects of additive gas(Ar, N{sub 2}, H{sub 2}), discharge composition and ICP source power and chuck power on etch rate and surface morphology has been performed. The general trends are to go through a maximum in etch rate with percent Cl{sub 2} in the discharge for all three mixtures, and to have an increase(decrease) in etch rate with source power(pressure). Since the etching is strongly ion-assisted, anisotropic pattern transfer is readily achieved. Maximum etch selectivities of approximately 6 for InN over the other nitrides were obtained.

Cho, Hyun; Vartuli, C.B.; Abernathy, C.R.; Donovan, S.M.; Pearton, S.J. [Florida Univ., Gainesville, FL (United States). Dept. of Materials Science and Engineering; Shul, R.J.; Han, J. [Sandia National Labs., NM (United States)

1997-12-01T23:59:59.000Z

374

CX-009000: Categorical Exclusion Determination | Department of Energy  

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

0: Categorical Exclusion Determination 0: Categorical Exclusion Determination CX-009000: Categorical Exclusion Determination "High Quality, Low Cost Bulk Gallium Nitride (GaN) Substrates Grown by the Electrochemical Solution Growth Method CX(s) Applied: A9, B3.6 Date: 08/20/2012 Location(s): Missouri Offices(s): Golden Field Office The U.S. Department of Energy (DOE) is proposing to provide federal funding to MEMC Electronic Materials, Inc. MEMC would conduct research and development activities for a two phase project to develop a new process method for growing large bulk gallium nitrate (GaN) crystals at low cost with improved functional properties." CX-009000.pdf More Documents & Publications CX-000845: Categorical Exclusion Determination Energy Storage Systems 2010 Update Conference Presentations - Day 3,

375

Vehicle Technologies Office: Power Electronics  

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

Power Electronics Power Electronics The power electronics activity focuses on research and development (R&D) for flexible, integrated, modular power electronics for power conditioning and control, including a power switch stage capable of running a variety of motors and loads. Efforts are underway to reduce overall system costs for these vehicles through the elimination of additional cooling loops to keep the power electronics within their safe operation ranges. These challenges are being met within the program through research in: Silicon carbide and Gallium Nitride semiconductors, which can be operated at much higher temperatures than current silicon semiconductors; Packaging innovations for higher temperature operation; Improved thermal control technologies; and

376

FORMING PROTECTIVE FILMS ON METAL  

DOE Patents (OSTI)

Methods are described of inhibiting the corrosion of ferrous metal by contact with heavy liquid metals such as bismuth and gallium at temperatures above 500 icient laborato C generally by bringing nltrogen and either the metal zirconium, hafnium, or titanium into reactlve contact with the ferrous metal to form a thin adherent layer of the nitride of the metal and thereafter maintaining a fractional percentage of the metal absorbed in the heavy liquid metal in contact with the ferrous metal container. The general purpose for uslng such high boiling liquid metals in ferrous contalners would be as heat transfer agents in liquid-metal-fueled nuclear reactors.

Gurinsky, D.H.; Kammerer, O.F.; Sadofsky, J.; Weeks, J.R.

1958-12-16T23:59:59.000Z

377

Mapping the nonlinear optical susceptibility by noncollinear second harmonic generation  

E-Print Network (OSTI)

We present a method, based on noncollinear second harmonic generation, to evaluate the non-zero elements of the nonlinear optical susceptibility. At a fixed incidence angle, the generated signal is investigated by varying the polarization state of both fundamental beams. The resulting polarization charts allows to verify if Kleinman symmetry rules can be applied to a given material or to retrieve the absolute value of the nonlinear optical tensor terms, from a reference measurement. Experimental measurements obtained from Gallium Nitride layers are reported. The proposed method does not require an angular scan thus is useful when the generated signal is strongly affected by sample rotation

Larciprete, M C; Giardina, M; Belardini, A; Centini, M; Sibilia, 1 C; Bertolotti, M; Passaseo, A; Tasco, V

2009-01-01T23:59:59.000Z

378

Power Electronics Reliability Kick Off Meeting Â… Silicon Power Corp. & Sandia Labs  

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

Reliability Reliability 2010 Update Conference - DOE ESS Program November 4, 2010 Mark A. Smith - Systems Readiness & Sustainment Technologies Robert Kaplar, Matthew Marinella, Reinhard Brock, James Stanley, and Michael King - Radiation Hard CMOS Technology Stan Atcitty - Energy Infrastructure and Distributed Energy Resources Sandia National Laboratories Thanks to Dr. Imre Gyuk for supporting this work. Project Goals * Use experiments and modeling to investigate and characterize stress-related failure modes of post-silicon power electronic (PE) devices such as silicon carbide (SiC) and gallium nitride (GaN) switches. * Seek opportunities for condition monitoring (CM) and prognostics and health management (PHM) to further enhance the reliability of power electronics devices and equipment.

379

Constricted glow discharge plasma source  

SciTech Connect

A constricted glow discharge chamber and method are disclosed. The polarity and geometry of the constricted glow discharge plasma source is set so that the contamination and energy of the ions discharged from the source are minimized. The several sources can be mounted in parallel and in series to provide a sustained ultra low source of ions in a plasma with contamination below practical detection limits. The source is suitable for applying films of nitrides such as gallium nitride and oxides such as tungsten oxide and for enriching other substances in material surfaces such as oxygen and water vapor, which are difficult process as plasma in any known devices and methods. The source can also be used to assist the deposition of films such as metal films by providing low-energy ions such as argon ions.

Anders, Andre (Albany, CA); Anders, Simone (Albany, CA); Dickinson, Michael (San Leandro, CA); Rubin, Michael (Berkeley, CA); Newman, Nathan (Winnetka, IL)

2000-01-01T23:59:59.000Z

380

Recycling of wasted energy : thermal to electrical energy conversion  

E-Print Network (OSTI)

of Amorphous Gallium Indium Zinc Oxide NonvolatileAmorphous gallium indium zinc oxide thin film transistors:Effects in Amorphous Gallium–Indium Zinc- xv Oxide Thin Film

Lim, Hyuck

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "gallium nitride ingan" 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

Microsoft Word - 25A2445 Continued  

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

This ARPA-E program plans to address the vast energy loss and consumption associated with conventional lighting by developing a new This ARPA-E program plans to address the vast energy loss and consumption associated with conventional lighting by developing a new route to large, high-quality, single crystals of gallium nitride. These crystals will serve as substrates for LEDs offering high-efficiency lighting. Around 8% of the energy consumption in the U.S. is from lighting, and by 2025, the U.S. could consume as much as 1,000 TWh per year. In addition, conventional light sources can account for more than 25% of a building's energy demands in the forms of direct energy for lighting, waste heat from the lights, and higher HVAC costs due to the waste heat. With its more efficient light production and minimal waste heat, gallium-nitride (GaN) Solid- State Lighting (SSL) technology has the potential to reduce energy consumption by

382

High-efficiency solar cell and method for fabrication  

DOE Patents (OSTI)

A high-efficiency 3- or 4-junction solar cell is disclosed with a theoretical AM0 energy conversion efficiency of about 40%. The solar cell includes p-n junctions formed from indium gallium arsenide nitride (InGaAsN), gallium arsenide (GaAs) and indium gallium aluminum phosphide (InGaAlP) separated by n-p tunnel junctions. An optional germanium (Ge) p-n junction can be formed in the substrate upon which the other p-n junctions are grown. The bandgap energies for each p-n junction are tailored to provide substantially equal short-circuit currents for each p-n junction, thereby eliminating current bottlenecks and improving the overall energy conversion efficiency of the solar cell. Additionally, the use of an InGaAsN p-n junction overcomes super-bandgap energy losses that are present in conventional multi-junction solar cells. A method is also disclosed for fabricating the high-efficiency 3- or 4-junction solar cell by metal-organic chemical vapor deposition (MOCVD). 4 figs.

Hou, H.Q.; Reinhardt, K.C.

1999-08-31T23:59:59.000Z

383

High-efficiency solar cell and method for fabrication  

DOE Patents (OSTI)

A high-efficiency 3- or 4-junction solar cell is disclosed with a theoretical AM0 energy conversion efficiency of about 40%. The solar cell includes p-n junctions formed from indium gallium arsenide nitride (InGaAsN), gallium arsenide (GaAs) and indium gallium aluminum phosphide (InGaAlP) separated by n-p tunnel junctions. An optional germanium (Ge) p-n junction can be formed in the substrate upon which the other p-n junctions are grown. The bandgap energies for each p-n junction are tailored to provide substantially equal short-circuit currents for each p-n junction, thereby eliminating current bottlenecks and improving the overall energy conversion efficiency of the solar cell. Additionally, the use of an InGaAsN p-n junction overcomes super-bandgap energy losses that are present in conventional multi-junction solar cells. A method is also disclosed for fabricating the high-efficiency 3- or 4-junction solar cell by metal-organic chemical vapor deposition (MOCVD).

Hou, Hong Q. (Albuquerque, NM); Reinhardt, Kitt C. (Albuquerque, NM)

1999-01-01T23:59:59.000Z

384

IEEE TRANSACTIONS ON NUCLEAR SCIENCE, VOL. 55, NO. 6, DECEMBER 2008 3633 Radiation Effects on InGaN Quantum Wells  

E-Print Network (OSTI)

GaN Quantum Wells and GaN Simultaneously Probed by Ion Beam-Induced Luminescence J. W. Tringe, Member, IEEE, A. Stevens, and C. Wetzel, Member, IEEE Abstract--InGaN quantum well structures on GaN epilayers were exposed of the epilayer and wells. Performance was estimated by the intensity of ion-beam induced luminescence. Two

Wetzel, Christian M.

385

Fabrication and Characterization of III-Nitride Solar Cells.  

E-Print Network (OSTI)

??In this thesis, first we use the program AMPS-1D (Analysis of Microelectronic and Photonic Structures) developed by the Pennsylvania State University to simulate the electrical… (more)

Deng, Tsung-Wei

2013-01-01T23:59:59.000Z

386

Point Defect Control in Power III-Nitride Semiconductors  

Science Conference Proceedings (OSTI)

Symposium, Advanced Materials for Power Electronics, Power Conditioning, and ... Characterization of Degradation for MLCC under Thermal and Electrical ...

387

Observation of visible luminescence from indium nitride at room temperature  

SciTech Connect

InN films were grown on sapphire substrates with AlN buffer layers by reactive sputtering. C-axis-oriented crystalline InN films with a wurtzite structure were confirmed by x-ray diffraction and Raman scattering. Strong photoluminescence (PL) at 1.87 eV, together with a clear absorption edge at 1.97 eV, was observed at room temperature, which clearly demonstrates that it is not accurate in the previous assignment of an {approx}0.7 eV fundamental band gap for intrinsic InN simply from PL and absorption data. The possible origin of the present large band gap was discussed in terms of the effects of oxygen and the Burstein-Moss shift.

Guo, Q.X.; Tanaka, T.; Nishio, M.; Ogawa, H.; Pu, X.D.; Shen, W.Z. [Department of Electrical and Electronic Engineering, Saga University, Saga 840-8502 (Japan); Laboratory of Condensed Matter Spectroscopy and Opto-Electronic Physics, Department of Physics, Shanghai Jiao Tong University, 1954 Hua Shan Road, Shanghai 200030 (China)

2005-06-06T23:59:59.000Z

388

Nitride semiconductor Surface and interface characterization and device design  

E-Print Network (OSTI)

Dev. 48 , 444 (2001) J. M. Redwing, M. A. Tischler, J. S.K. S. Boutros, and J. M. Redwing, Appl. Phys. Lett. 73 ,

Zhang, Hongtao

2006-01-01T23:59:59.000Z

389

Elements of Power Conversion Integration in Group-III Nitride ...  

Science Conference Proceedings (OSTI)

Symposium, Advanced Materials for Power Electronics, Power Conditioning, and Power Conversion ... Potential Ceramic Dielectrics for Air Force Applications.

390

Growth and characterization of ultrathin nitrided silicon oxide films  

Science Conference Proceedings (OSTI)

This paper reviews recent progress in understanding microstructural and growth-mechanistic aspects of ultrathin (<4 nm) oxynitride films for gate dielectric applications. Different techniques for characterizing these films are summarized. We discuss ...

E. P. Gusev; H.-C. Lu; E. L. Garfunkel; T. Gustafsson; M. L. Green

1999-05-01T23:59:59.000Z

391

Mixed Mode Fracture in Silicon Nitride Disks Using the Brazilian ...  

Science Conference Proceedings (OSTI)

Analysis of a Bucketwheel Stacker Reclaimer Structural Failure · Analysis of Glass Breakage · Analysis of Sealed, Integrated, Automotive Wheel Bearings.

392

Boron nitride protective coating of beryllium window surfaces  

SciTech Connect

The use of beryllium windows on white synchrotron radiation beamlines is constrained by the fact that the downstream surfaces of these windows should not be exposed to ambient atmosphere. They should, rather, be protected by a tail-piece under vacuum or containing helium atmosphere. This tailpiece is typically capped by Kapton (3M Corporation, St. Paul, MN) or aluminum foil. The reason for such an arrangement is due to the health risk associated with contaminants (BeO) which from on the exposed beryllium window surfaces and due to possible loss of integrity of the windows. Such a tail-piece may, however, add unwanted complications to the beamline in the form of vacuum pumps or helium supplies and their related monitoring systems. The Kapton windows may burn through in the case of high intensity beams and lower energy radiation may be absorbed in the case of aluminum foil windows. A more ideal situation would be to provide a coating for the exposed beryllium window surface, sealing it off from the atmosphere, thus preventing contamination and/or degradation of the window, and eliminating the need for helium or vacuum equipment.

Gmuer, N.F.

1991-12-01T23:59:59.000Z

393

Structural and Morphological Properties of Niobium Nitride Thin ...  

Science Conference Proceedings (OSTI)

A Study on Contact Resistance Failure between Al-Ti-TiN Multi-layer and W-via ... of Superlattices Through Phase Transformation by Low-Energy Ion Irradiation.

394

Metal Nitride Catalysts to Enhance Hydrogen Evolution Reactions  

growing energy generation and utilization technologies. For example, water electrolysis can transform electrical energy produced by solar cells into ...

395

Synthesis of actinide nitrides, phosphides, sulfides and oxides  

DOE Patents (OSTI)

This invention is comprised of a process of preparing an actinide compound of the formula An{sub x}Z{sub y} wherein An is an actinide metal atom selected from the group consisting of thorium, uranium, plutonium, neptunium, and americium, x is selected from the group consisting of one, two or three, Z is a main group element atom selected from the group consisting of nitrogen, phosphorus, oxygen and sulfur and y is selected from the group consisting of one, two, three or four, by admixing an actinide organometallic precursor wherein said actinide is selected from the group consisting of thorium, uranium, plutonium, neptunium, and americium, a suitable solvent and a protic Lewis base selected from the group consisting of ammonia, phosphine, hydrogen sulfide and water, at temperatures and for time sufficient to form an intermediate actinide complex, heating said intermediate actinide complex at temperatures and for time sufficient to form the actinide compound, and a process of depositing a thin film of such an actinide compound, e.g., uranium mononitride, by subliming an actinide organometallic precursor, e.g., a uranium amide precursor, in the presence of an effective amount of a protic Lewis base, e.g., ammonia, within a reactor at temperatures and for time sufficient to form a thin film of the actinide compound, are disclosed.

Van Der Sluys, W.G.; Burns, C.J.; Smith, D.C.

1991-04-02T23:59:59.000Z

396

Graphene Coated with Titanium Nitride as Electrode Materials for ...  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, 2013 TMS Annual Meeting & Exhibition. Symposium , 2013 and Beyond: Flexible Electronics. Presentation Title, Graphene Coated ...

397

Simulation of the Ferritic Nitriding Process - Database Development  

Science Conference Proceedings (OSTI)

In this paper a preliminary version of the simulation tool will be presented and discussed in terms of database ... 25 Years of Thermochemistry Applications.

398

Method and apparatus for aluminum nitride monocrystal boule growth  

DOE Patents (OSTI)

A crystal growth setup within a physical vapor transport growth furnace system for producing AlN monocrystal boules at high temperatures includes a crucible effective to contain an AlN source material and a growing AlN crystal boule. This crucible has a thin wall thickness in at least that portion housing the growing AlN crystal boule. Other components include a susceptor, in case of an inductive heating, or a heater, in case of a resistive heating, a thermal insulation enclosing the susceptor or heater effective to provide a thermal gradient inside the crucible in the range of 5-100.degree. C./cm and a furnace chamber capable of being operated from a vacuum (<0.1 torr) to a gas pressure of at least 4000 torr through filling or flowing a nitrogen gas or a mixture of nitrogen gas and argon gas. The high temperatures contribute to a high boule growth rate and the thin wall thickness contributes to reduced imparted stress during boule removal.

Wang, Shaoping (Brookfield, CT)

2009-04-28T23:59:59.000Z

399

C-7: Gaseous Nitriding Process Control: Application of Customized ...  

Science Conference Proceedings (OSTI)

... investigation and this proves the utility of using thermodynamic database to .... the Asymptotic Grain Face Distribution in Terms of Tological Event Rates.

400

A Novel Method for Manufacturing Aluminum-Aluminum Nitride ...  

Science Conference Proceedings (OSTI)

One-Dimensional ZnO Nanostructures for Photonic and Optoelectronic Applications · Optical Thin Films for Gas Sensing in Advanced Coal Fired Power Plants.

Note: This page contains sample records for the topic "gallium nitride ingan" 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

PUBLICATIONS "Ultrafast Photoluminescence Dynamics Of Nitride Passivated Silicon  

E-Print Network (OSTI)

as psychological differences between individuals are not ad- dressed (Hulin, 1971). Efforts focused primarily.V. (1959). The motivation to work. New York: Wiley. Hulin, C.L. (1971). Individual differences and job-Bass. Renwick, P.A. (1975). Perception and management of superior­subordinate conflict. Organiza- tional

Fauchet, Philippe

402

Zinc Oxide and Nitride Nanowire Based Light Emitting Diodes  

E-Print Network (OSTI)

light sources have wasted emission and energy as can be seenor in other words, wasted electrical energy). Extraction

Lai, Elaine Michelle

2009-01-01T23:59:59.000Z

403

Zinc Oxide and Nitride Nanowire Based Light Emitting Diodes  

E-Print Network (OSTI)

lumens/W, the LED beats the incandescent bulb and is on thefor an LED as opposed to an incandescent light bulb as shownbulb, fluorescent lamp, and blue light emitting diode. (24) (25) 2.2 LED

Lai, Elaine Michelle

2009-01-01T23:59:59.000Z

404

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

405

Synthesis of actinide nitrides, phosphides, sulfides and oxides  

DOE Green Energy (OSTI)

A process of preparing an actinide compound of the formula An.sub.x Z.sub.y wherein An is an actinide metal atom selected from the group consisting of thorium, uranium, plutonium, neptunium, and americium, x is selected from the group consisting of one, two or three, Z is a main group element atom selected from the group consisting of nitrogen, phosphorus, oxygen and sulfur and y is selected from the group consisting of one, two, three or four, by admixing an actinide organometallic precursor wherein said actinide is selected from the group consisting of thorium, uranium, plutonium, neptunium, and americium, a suitable solvent and a protic Lewis base selected from the group consisting of ammonia, phosphine, hydrogen sulfide and water, at temperatures and for time sufficient to form an intermediate actinide complex, heating said intermediate actinide complex at temperatures and for time sufficient to form the actinide compound, and a process of depositing a thin film of such an actinide compound, e.g., uranium mononitride, by subliming an actinide organometallic precursor, e.g., a uranium amide precursor, in the presence of an effectgive amount of a protic Lewis base, e.g., ammonia, within a reactor at temperatures and for time sufficient to form a thin film of the actinide compound, are disclosed.

Van Der Sluys, William G. (Missoula, MT); Burns, Carol J. (Los Alamos, NM); Smith, David C. (Los Alamos, NM)

1992-01-01T23:59:59.000Z

406

Microstructure and Coercivity of Nitrided Mn-Sn Based Alloy  

Science Conference Proceedings (OSTI)

Alloy Design and Powder Processing of Mn-Al Based Materials for Rare Earth ... Enhancement of the Refrigerant Capacity in Partially Crystallized Gd-Fe-Al-B ...

407

Density and Thermal Conductivity of Boron Nitride-alumina Mixed ...  

Science Conference Proceedings (OSTI)

Synthesis and Characterization of Plasma Polymerized Thin Films Deposited from Benzene and Hexamethyldisiloxane Using (PECVD) Method · Synthesis and ...

408

Mechanism of Metal Titanium Powder Nitriding under Microwave ...  

Science Conference Proceedings (OSTI)

Author(s), Keiichiro Kashimura, Jun Fukushima, Motoyasu Sato. On-Site Speaker (Planned), Keiichiro Kashimura. Abstract Scope, Chemical reaction under ...

409

Surface Hardening in Nitrided Ferrous Alloys by Nano-sized ...  

Science Conference Proceedings (OSTI)

D8: Study of Rack and Chord Assembly Formability for Jack-up Platforms ... Zone of Zr-Ti Microalloyed High-strength High-toughness Offshore Structural Steels.

410

G9 Mechanical Properties of Nitrided Martensitic Stainless Steel 431 ...  

Science Conference Proceedings (OSTI)

D14 Gold Nanoparticles in Red Ruby Glasses Used for Decoration in Thailand · D15 Soft Magnetic Properties of Nanocrystalline Fe-based P/M Cores Mixed ...

411

Session M: III-Nitrides: Defects and LEDs  

Science Conference Proceedings (OSTI)

Jun 22, 2011 ... A correlation has been established between the optical and structural properties of blue light-emitting diode structures with an indium ...

412

High-Efficiency Nitride-Base Photonic Crystal Light Sources  

DOE Green Energy (OSTI)

The research activities performed in the framework of this project represent a major breakthrough in the demonstration of Photonic Crystals (PhC) as a competitive technology for LEDs with high light extraction efficiency. The goals of the project were to explore the viable approaches to manufacturability of PhC LEDS through proven standard industrial processes, establish the limits of light extraction by various concepts of PhC LEDs, and determine the possible advantages of PhC LEDs over current and forthcoming LED extraction concepts. We have developed three very different geometries for PhC light extraction in LEDs. In addition, we have demonstrated reliable methods for their in-depth analysis allowing the extraction of important parameters such as light extraction efficiency, modal extraction length, directionality, internal and external quantum efficiency. The information gained allows better understanding of the physical processes and the effect of the design parameters on the light directionality and extraction efficiency. As a result, we produced LEDs with controllable emission directionality and a state of the art extraction efficiency that goes up to 94%. Those devices are based on embedded air-gap PhC - a novel technology concept developed in the framework of this project. They rely on a simple and planar fabrication process that is very interesting for industrial implementation due to its robustness and scalability. In fact, besides the additional patterning and regrowth steps, the process is identical as that for standard industrially used p-side-up LEDs. The final devices exhibit the same good electrical characteristics and high process yield as a series of test standard LEDs obtained in comparable conditions. Finally, the technology of embedded air-gap patterns (PhC) has significant potential in other related fields such as: increasing the optical mode interaction with the active region in semiconductor lasers; increasing the coupling of the incident light into the active region of solar cells; increasing the efficiency of the phosphorous light conversion in white light LEDs etc. In addition to the technology of embedded PhC LEDs, we demonstrate a technique for improvement of the light extraction and emission directionality for existing flip-chip microcavity (thin) LEDs by introducing PhC grating into the top n-contact. Although, the performances of these devices in terms of increase of the extraction efficiency are not significantly superior compared to those obtained by other techniques like surface roughening, the use of PhC offers some significant advantages such as improved and controllable emission directionality and a process that is directly applicable to any material system. The PhC microcavity LEDs have also potential for industrial implementation as the fabrication process has only minor differences to that already used for flip-chip thin LEDs. Finally, we have demonstrated that achieving good electrical properties and high fabrication yield for these devices is straightforward.

James Speck; Evelyn Hu; Claude Weisbuch; Yong-Seok Choi; Kelly McGroddy; Gregor Koblmuller; Elison Matioli; Elizabeth Rangel; Fabian Rol; Dobri Simeonov

2010-01-31T23:59:59.000Z

413

Hydrogen incorporation into III-V nitrides during processing  

DOE Green Energy (OSTI)

Hydrogen is readily incorporated into GaN and related alloys during wet and dry etching, chemical vapor deposition of dielectric overlayers, boiling in water and other process steps, in addition to its effects during MOCVD or MOMBE growth. The hydrogen is bound at defects or impurities and passivates their electrical activity. Reactivation occurs at 450-550{degrees}C, but evolution from the crystal requires much higher temperatures ({ge} 800{degrees}C).

Pearton, S.J.; Abernathy, C.R.; Vartuli, C.B. [Univ. of Florida, Gainesville, FL (United States)] [and others

1995-10-01T23:59:59.000Z

414

G3: Nitriding Surface Treatments to Improve Water Droplet Erosion ...  

Science Conference Proceedings (OSTI)

A8: Microstructural Investigation of Nano-Calcium Phosphates Doped with Fluoride Ions .... D7: Surfactant Structure–property Relationship: Effect of Polypropylene ... E4: The Effect of Monobutyl Ether Ethylene Glycol on the Conductivity and ...

415

Boron Nitride Nanotube Reinforced Metal and Ceramic Composites ...  

Science Conference Proceedings (OSTI)

Functional Composites: Fluorescent Carbon Nanotubes in Silica Aerogel ... Novel Metallo-Organic Derived Ti-Si-Cr-C-N Nanocomposite Coatings: Part II ...

416

Zinc Oxide and Nitride Nanowire Based Light Emitting Diodes  

E-Print Network (OSTI)

1-x)Ga(x)N alloys: Full-solar-spectrum photovoltaic materialas compared to solar spectrum, taken from LBL website (as compared to solar spectrum, taken from LBL website (50)

Lai, Elaine Michelle

2009-01-01T23:59:59.000Z

417

Borazine-boron nitride hybrid hydrogen storage system  

DOE Patents (OSTI)

A hybrid hydrogen storage composition includes a first phase and a second phase adsorbed on the first phase, the first phase including BN for storing hydrogen by physisorption and the second phase including a borazane-borazine system for storing hydrogen in combined form as a hydride.

Narula, Chaitanya K. (Knoxville, TN); Simonson, J. Michael (Knoxville, TN); Maya, Leon (Knoxville, TN); Paine, Robert T. (Albuquerque, NM)

2008-04-22T23:59:59.000Z

418

Future Challenges and Directions for Nitride Materials and Light Emitters  

E-Print Network (OSTI)

. Keywords--High-temperature techniques, light emitting diodes, materials science and technology@meijo-u.ac.jp). Publisher Item Identifier S 0018-9219(97)08491-0. blue light emitting diode (LED) devices emitted

Wetzel, Christian M.

419

F1: Effect of Boron Nitride Nanotube in Titanium Composite  

Science Conference Proceedings (OSTI)

The milling mixed powders were then hot consolidated to produce the composites. ... FRP Facesheets and Nanoclay-wood Flour Modified Polyurethane Foam.

420

Nitride semiconductors studied by atom probe tomography and correlative techniques  

E-Print Network (OSTI)

in hope or fear; But, grateful, take the good I find, The best of now and here.’ -- John Greenleaf Whittier Acknowledgements iv I am grateful to the many people who have helped and supported me during my three years in the Cambridge Centre... .2.1.2. Challenges to the island coalescence theory .................................................. 48 3.2.2. Effect of TDs ...................................................................................... 53 3.2.2.1. Non-radiative recombination model...

Bennett, Samantha

2011-02-08T23:59:59.000Z

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


421

Nanostructured Nitride-based Thin Films with Enhanced ...  

Science Conference Proceedings (OSTI)

Engineered Nanoparticles as Improved Oil Recovery and Flow Assurance Agents Under Harsh Reservoir Conditions · Enhanced Fatigue Property of a ...

422

Session O: III-Nitrides: UV Emitters and Detectors  

Science Conference Proceedings (OSTI)

Jun 23, 2011 ... A light emitting diode grown on AlN single crystal substrates based on pseudomorphic AlGaN films will be described. In addition, an estimation ...

423

GaN-Ready Aluminum Nitride Substrates for Cost-Effective, Very Low Dislocation Density III-Nitride LED's  

SciTech Connect

The objective of this project was to develop and then demonstrate the efficacy of a costeffective approach for a low defect density substrate on which AlInGaN LEDs can be fabricated. The efficacy of this “GaN-ready” substrate would then be tested by growing high efficiency, long lifetime InxGa1-xN blue LEDs. The approach used to meet the project objectives was to start with low dislocation density AlN single-crystal substrates and grow graded AlxGa1-xN layers on top. Pseudomorphic AlxGa1-xN epitaxial layers grown on bulk AlN substrates were used to fabricate light emitting diodes and demonstrate better device performance as a result of the low defect density in these layers when benched marked against state-of-the-art LEDs fabricated on sapphire substrates. The pseudomorphic LEDs showed excellent output powers compared to similar wavelength devices grown on sapphire substrates, with lifetimes exceeding 10,000 hours (which was the longest time that could reliably be estimated). In addition, high internal quantum efficiencies were demonstrated at high driving current densities even though the external quantum efficiencies were low due to poor photon extraction. Unfortunately, these pseudomorphic LEDs require high Al content so they emit in the ultraviolet. Sapphire based LEDs typically have threading dislocation densities (TDD) > 108 cm-2 while the pseudomorphic LEDs have TDD ? 105 cm-2. The resulting TDD, when grading the AlxGa1-xN layer all the way to pure GaN to produce a “GaN-ready” substrate, has varied between the mid 108 down to the 106 cm-2. These inconsistencies are not well understood. Finally, an approach to improve the LED structures on AlN substrates for light extraction efficiency was developed by thinning and roughening the substrate.

Sandra Schujman; Leo Schowalter

2010-10-15T23:59:59.000Z

424

Gallium Safety in the Laboratory INEEL/CON-03-00078  

Office of Scientific and Technical Information (OSTI)

This is a preprint of a paper intended for publication in a This is a preprint of a paper intended for publication in a journal or proceedings. Since changes may be made before publication, this preprint should not be cited or reproduced without permission of the author. This document was prepared as a account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, or any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for any third party's use, or the results of such use, of any information, apparatus, product or process disclosed in this report, or represents that its use by such third party would not infringe privately owned rights. The views expressed in this paper are

425

Analysis of amorphous indium-gallium-zinc-oxide thin-film transistor contact metal  

E-Print Network (OSTI)

, 157-159 (2008). 22 W.L. Bragg, Philosophical Magazine Series 6, 40:236, 169-189 (1920). 23 N.E. Holden, Pure & Appl. Chem. 52, 2349-2384 (1979). 24 J.F. Shackelford and W. Alexander, Materials science and engineering handbook, ed. 3. (CRC...

Kiani, Ahmed; Hasko, David G.; Milne, William I.; Flewitt, Andrew J.

2013-04-15T23:59:59.000Z

426

Quantum wells on indium gallium arsenic compositionally graded buffers realized by molecular beam epitaxy  

E-Print Network (OSTI)

For a long time, there has been a desire to extend the emission wavelength of GaAs-based quantum well lasers, with the aim of eventually replacing InP with GaAs as the substrate of choice for communication applications. ...

Choy, Henry Kwong Hin, 1974-

2005-01-01T23:59:59.000Z

427

Synthesis, Structure, and Molecular Dynamics of Gallium Complexes of Schizokinen and the Amphiphilic  

E-Print Network (OSTI)

). The activation parameters found for the two sequential steps of the proton independent pathway were Hq ) 25 ( 3 kcal M-1 , Sq ) 25 ( 7 cal M-1 K-1 and Hq ) 17.1 ( 0.2 kcal M-1 , Sq ) 0.3 ( 2.7 cal M-1 K-1 organic compounds that are produced by microorganisms in response to iron deficiency. These compounds

Groves, John T.

428

Dependence of carrier mobility on an electric field in gallium selenide crystals  

Science Conference Proceedings (OSTI)

The dependence of the mobility of charge carriers on voltage has been studied in undoped GaSe single crystals and crystals doped with gadolinium; the latter crystals have exhibited various values of dark resistivity ({rho}{sub d.r} Almost-Equal-To 10{sup 4}-10{sup 8} {Omega} cm at 77 K) and of the doping level (N = 10{sup -5}, 10{sup -4}, 10{sup -3}, 10{sup -2}, and 10{sup -1} at %). It is established that the dependence of the charge-carrier mobility on the electric field applied to the sample E {=} 10{sup 4} {Omega} cm) and in lightly doped GaSe crystals (N {<=} 10{sup -2} at %) in the region of T {<=} 150 K. It is found that this dependence is not related to heating of the charge carriers by an electric field; rather, it is caused by elimination of drift barriers as a result of injection.

Abdinov, A. Sh., E-mail: abdinov_axmed@yahoo.com; Babaeva, R. F., E-mail: Babaeva-Rena@yandex.ru; Rzayev, R. M. [Baku State University (Azerbaijan)

2012-06-15T23:59:59.000Z

429

Selective growth experiments on gallium arsenide (100) surfaces patterned using UV-nanoimprint lithography  

Science Conference Proceedings (OSTI)

We describe a nanoimprint lithography (NIL) process and subsequent solid-source molecular beam epitaxy (SSMBE) growth of III-V semiconductors on patterned substrates. In particular, growth of GaAs, GaInAs, and GaInP, and effects of growth temperature ... Keywords: Molecular beam epitaxy, Nanoimprint lithography, Patterned substrates, Selective growth

A. Tukiainen; J. Viheriälä; T. Niemi; T. Rytkönen; J. Kontio; M. Pessa

2006-12-01T23:59:59.000Z

430

ISOTHERMAL (DELTA)/(ALPHA-PRIME) TRANSFORMATION AND TTT DIAGRAM IN A PLUTONIUM GALLIUM ALLOY  

Science Conference Proceedings (OSTI)

Differential scanning calorimetry (DSC) is used as an alternative approach to determining the tine-temperature-transformation (TTT) diagram for the martensitic delta to alpha-prime transformation in a Pu-2.0 at% Ga alloy. Previous work suggests that the TTT diagram for a similar alloy exhibits an unusual double-C curve for isothermal holds of less than 100 minutes. Here, we extend this diagram to 18 hours, and confirm the double-C curve behavior. When the sample is cooled prior to the isothermal holds, the delta to alpha-prime transformation is observed as several overlapping exothermic peaks. These peaks are very reproducible, and they are believed to be the result of different kinds of delta to alpha-prime martensitic transformation. This may be due to the presence of different nucleation sites and/or different morphologies.

Oudot, B P; Blobaum, K M; Wall, M A; Schwartz, A J

2005-11-11T23:59:59.000Z

431

GaN CVD Reactions: Hydrogen and Ammonia Decomposition and the Desorption of Gallium  

DOE Green Energy (OSTI)

Isotopic labeling experiments have revealed correlations between hydrogen reactions, Ga desorption, and ammonia decomposition in GaN CVD. Low energy electron diffraction (LEED) and temperature programmed desorption (TPD) were used to demonstrate that hydrogen atoms are available on the surface for reaction after exposing GaN(0001) to deuterium at elevated temperatures. Hydrogen reactions also lowered the temperature for Ga desorption significantly. Ammonia did not decompose on the surface before hydrogen exposure. However, after hydrogen reactions altered the surface, N15H3 did undergo both reversible and irreversible decomposition. This also resulted in the desorption of N2 of mixed isotopes below the onset of GaN sublimation, This suggests that the driving force of the high nitrogen-nitrogen bond strength (226 kcal/mol) can lead to the removal of nitrogen from the substrate when the surface is nitrogen rich. Overall, these findings indicate that hydrogen can influence G-aN CVD significantly, being a common factor in the reactivity of the surface, the desorption of Ga, and the decomposition of ammonia.

Bartram, Michael E.; Creighton, J. Randall

1999-05-26T23:59:59.000Z

432

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

DOE Green Energy (OSTI)

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

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

1993-02-01T23:59:59.000Z

433

The Interfacial Mechanics of the Thin Oxide Skin on Liquid Gallium ...  

Science Conference Proceedings (OSTI)

The ability to micromold the metal for these applications is enabled by the ... The oxide skin is elastic and yields under a critical stress, at which point the metal flows. ... Interface Bond Strength of HIP-Clad Depleted Uranium and 6061- Aluminum ... Quantitative NanoSIMS Analysis of Grain Boundary Segregation in Bulk ...

434

Sparse gallium arsenide to silicon metal waferbonding for heterogeneous monolithic microwave integrated circuits  

E-Print Network (OSTI)

New York Master of Science, Electrical Engineering (AppliedYork Bachelor of Science, Electrical Engineering RochesterElectronic Thin Film Science: For Electrical Engineers and

Bickford, Justin Robert

2008-01-01T23:59:59.000Z

435

Scintigraphic evaluation of Lyme disease: Gallium-67 imaging of Lyme myositis  

Science Conference Proceedings (OSTI)

A patient suffering from Lyme disease had cardiac conduction abnormalities, symptoms of arthritis, and myalgia. A Ga-67 image showed evidence of endomyocarditis, but intense skeletal muscle uptake pointed to Lyme myositis. Reference is made to two other case reports of Lyme myositis.

Kengen, R.A.; v.d. Linde, M.; Sprenger, H.G.; Piers, D.A. (Univ. Hospital, Groningen (Netherlands))

1989-10-01T23:59:59.000Z

436

Preconceptual Design For Separation Of Plutonium And Gallium By Ion Exchange  

E-Print Network (OSTI)

.............................................................................. 5 2.0 BACKGROUND.........................................................................5 3.0 PROCESS DESCRIPTION.............................................................6 3.1 Oxidation of Metal...............................................................7 3.2 Dissolution of Oxide............................................................ 8 3.3 Ion Exchange (IX).............................................................. 8 3.4 Plutonium Product Preparation................................................ 10 3.5 Recycle Operations..............................................................10 3.6 Waste Generation................................................................10 4.0 MATERIAL BALANCES...............................................................11 4.1 Dissolution of Oxide............................................................ 11 4.2 IX Feed Pretreatment.............................

Scott Demuth; Scott F. Demuth

1997-01-01T23:59:59.000Z

437

Active devices for high temperature microcircuitry. [Silicon and gallium arsenide devices  

DOE Green Energy (OSTI)

As part of a program to develop high temperature electronics for geothermal well instrumentation, a number of solid state diode and transistor types were characterized from room temperature to 300/sup 0/C. The temperature dependence and aging stability of transport and leakage properties were measured. Included in the study were silicon diodes, bipolar transistors, JFETs, MOSFETs, and GaAs MESFETs and JFETs. In summary the results are: diodes and bipolar transistors became extremely leaky at high temperature and are therefore of limited use; silicon MOSFETs and GaAs devices showed unacceptable aging instabilities at high temperatures; silicon JFETs from certain manufacturers were sufficiently stable and had suitable temperature dependent characteristics so that operational circuits could be made. Comparisons were made of experimental device characteristics and those predicted by theory. The theoretical calculations were done using standard equations revised to include appropriate temperature dependent parameters. Close agreement between theory and experiment was found, indicating that unexpected high temperature effects were insignificant. In order to facilitate the use of devices in high temperature hybrids, it was necessary to develop bonding and prescreening techniques. A large variance of JFET 300/sup 0/C operating parameters was found even within a single production lot. Consequently, high temperature prescreening allowed each circuit to be specifically ''pretuned.'' Standard solder, epoxy, and chip and wire attachment technologies were not functional at 300/sup 0/C. Gold-germanium solder, aluminum wire to DuPont 9910 gold film, and diffusion barrier pads were developed to allow high temperature attachment.

Palmer, D.W.; Draper, B.L.; McBrayer, J.D.; White, K.R.

1978-02-01T23:59:59.000Z

438

SAGE: Solar Neutrino Data from SAGE, the Russian-American Gallium Solar Neutrino Experiment  

DOE Data Explorer (OSTI)

SAGE is a solar neutrino experiment based on the reaction 71Ga + n goes to 71Ge + e-. The 71Ge atoms are chemically extracted from a 50-metric ton target of Ga metal and concentrated in a sample of germane gas mixed with xenon. The atoms are then individually counted by observing their decay back to 71Ga in a small proportional counter. The distinguishing feature of the experiment is its ability to detect the low-energy neutrinos from proton-proton fusion. These neutrinos, which are made in the primary reaction that provides the Sun's energy, are the major component of the solar neutrino flux and have not been observed in any other way. To shield the experiment from cosmic rays, it is located deep underground in a specially built facility at the Baksan Neutrino Observatory in the northern Caucasus mountains of Russia. Nearly 100 measurements of the solar neutrino flux have been made during 1990-2000, and their combined result is a neutrino capture rate that is well below the prediction of the Standard Solar Model. The significant suppression of the solar neutrino flux that SAGE and other solar neutrino experiments have observed gives a strong indication for the existence of neutrino oscillations. [copied from the SAGE homepage at http://ewi.npl.washington.edu/SAGE/SAGE.html

SAGE Collaboration

439

Transparent Conducting Contacts Based on Zinc Oxide Substitutionally Doped with Gallium: Preprint  

DOE Green Energy (OSTI)

Transparent conducting oxides (TCOs) are a critical element in photovoltaic devices. This paper describes research on Ga:ZnO (a TCO candidate) using a high-throughput combinatorial approach.

Gorrie, C. W.; Reese, M.; Perkins, J. D.; Alleman, J. L.; Dabney M. S.; To, B.; Ginley, D. S.; Berry, J. J.

2008-05-01T23:59:59.000Z

440

Synthesis and optical properties of CsC1-doped gallium-sodium-sulfide glasses  

SciTech Connect

Ga{sub 2}S{sub 3}-Na{sub 2}S (GNS) glasses doped with CsCl were synthesized in open crucibles under inert atmosphere. The evaporative loss of CsCl during glass melting was measured by energy dispersive X-ray spectroscopy and corrected for by biasing the CsCl concentration in the mixture of starting materials to obtain glasses with accurately controlled stoichiometry. Glass transition temperatures, refractive index dispersions, and band edge energies were measured for four GNS:CsCl glasses, and the respective values were found to significantly improve over earlier studies that did not mitigate CsCl evaporative losses. The refractive index dispersion measurements indicate that the Cs{sup +} and Cl{sup -} radii are 16% larger in GNS:CsCl glass than in bulk crystalline CsCl. The band edge energy increases from 2.97 eV in GNS glass to 3.32 eV in GNS glass doped with 20 mol% CsCl as a result of introducing Cl{sup -} ions having a large optical electronegativity. The large bandgap of 3.32 eV and the low (450 cm{sup -1}) phonon energy make GNS:20%CsCl an attractive host material for rare-earth ions with radiative transitions in the near ultra-violet, visible, and near-infrared spectral regions.

Hehlen, Markus P [Los Alamos National Laboratory; Bennett, Bryan L [Los Alamos National Laboratory; Williams, Darrick J [Los Alamos National Laboratory; Muenchausen, Ross E [Los Alamos National Laboratory; Castro, Alonso [Los Alamos National Laboratory; Tornga, Stephanie C [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "gallium nitride ingan" 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

Sparse gallium arsenide to silicon metal waferbonding for heterogeneous monolithic microwave integrated circuits  

E-Print Network (OSTI)

and V. I. Tsimbal, “Electrical Resistivity of Pd-In Alloys,”and V. I. Tsimbal, “Electrical Resistivity of Pd-In Alloys,”and V. I. Tsimbal, “Electrical Resistivity of Pd-In Alloys,”

Bickford, Justin Robert

2008-01-01T23:59:59.000Z

442

Page not found | Department of Energy  

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

61 - 17070 of 31,917 results. 61 - 17070 of 31,917 results. Download CX-001136: Categorical Exclusion Determination 130 Lumens Per Watt 1000 Lumen Warm White LEDs (Light-Emitting Diodes) for Illumination CX(s) Applied: B3.6, B5.1 Date: 03/05/2010 Location(s): San Jose, California Office(s): Energy Efficiency and Renewable Energy, National Energy Technology Laboratory http://energy.gov/nepa/downloads/cx-001136-categorical-exclusion-determination Download CX-001137: Categorical Exclusion Determination Advanced Epi Tools for Gallium Nitride LED (Light Emitting Diode) Devices CX(s) Applied: B3.6 Date: 03/05/2010 Location(s): Santa Clara, California Office(s): Energy Efficiency and Renewable Energy, National Energy Technology Laboratory http://energy.gov/nepa/downloads/cx-001137-categorical-exclusion-determination

443

CX-005363: Categorical Exclusion Determination | Department of Energy  

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

5363: Categorical Exclusion Determination 5363: Categorical Exclusion Determination CX-005363: Categorical Exclusion Determination Solar Junction's 100 Megawatt Manufacturing Line CX(s) Applied: B1.31 Date: 03/04/2011 Location(s): San Jose, California Office(s): Loan Guarantee Program Office The Department of Energy's proposed action is to issue a loan guarantee to Solar Junction to finance a 100 megawatt (MW) solar cell manufacturing line for multifunction photovoltaic solar cells to expand their existing 7 MW Demonstration Facility at 401 Charcot Avenue, San Jose, California 95131. The proposed project will commercialize an entirely new class of high-efficiency solar cells and concentrating photovoltaic components that incorporate high performance junctions formed with a tunable band gap semiconductor material, Gallium Indium Nitride Arsenide.

444

Categorical Exclusion Determinations: New York | Department of Energy  

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

January 15, 2010 January 15, 2010 CX-000845: Categorical Exclusion Determination 25A2445 - Ammonothermal Bulk Gallium Nitride (GaN) Crystal Growth for Energy Efficient Lighting CX(s) Applied: B3.6 Date: 01/15/2010 Location(s): New York Office(s): Advanced Research Projects Agency - Energy December 29, 2009 CX-000273: Categorical Exclusion Determination Pressure Sensor and Telemetry Methods for Measurement while Drilling in Geothermal Wells CX(s) Applied: A9, B3.6 Date: 12/29/2009 Location(s): New York Office(s): Energy Efficiency and Renewable Energy, Golden Field Office December 21, 2009 CX-001281: Categorical Exclusion Determination Hire Experts, Lighting Retrofits, and Install Solar Lights CX(s) Applied: A9, B5.1 Date: 12/21/2009 Location(s): Suffolk, New York Office(s): Energy Efficiency and Renewable Energy

445

Advanced Power Electronics for LED Drivers: Advanced Technologies for integrated Power Electronics  

SciTech Connect

ADEPT Project: MIT is teaming with Georgia Institute of Technology, Dartmouth College, and the University of Pennsylvania (UPenn) to create more efficient power circuits for energy-efficient light-emitting diodes (LEDs) through advances in 3 related areas. First, the team is using semiconductors made of high-performing gallium nitride grown on a low-cost silicon base (GaN-on-Si). These GaN-on-Si semiconductors conduct electricity more efficiently than traditional silicon semiconductors. Second, the team is developing new magnetic materials and structures to reduce the size and increase the efficiency of an important LED power component, the inductor. This advancement is important because magnetics are the largest and most expensive part of a circuit. Finally, the team is creating an entirely new circuit design to optimize the performance of the new semiconductors and magnetic devices it is using.

2010-09-01T23:59:59.000Z

446

BridgeLux | Open Energy Information  

Open Energy Info (EERE)

BridgeLux BridgeLux Jump to: navigation, search Logo: BridgeLux Name BridgeLux Address 1170 Sonora Court Place Sunnyvale, California Zip 94086 Sector Efficiency Product Designs and makes high power indium gallium nitride light emitting diodes Website http://www.bridgelux.com/ Coordinates 37.371138°, -121.998365° 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":37.371138,"lon":-121.998365,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

447

 

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

Defect-Driven Magnetism in Mn-doped GaN Defect-Driven Magnetism in Mn-doped GaN Semiconductors doped with magnetic elements are very interesting materials. In these materials, the magnetic impurities interact with and induce magnetism in the semiconductor host. Thus, they have the potential for combining magnetism with the rich electronic behavior of semiconductors, which may lead to new generations of low-power-consumption electronics, non-volatile memories, and field-configurable logic devices. Gallium nitride doped with Mn is particularly interesting because it is one of the few materials for which magnetism above room temperature has been reported, making it a candidate room-temperature magnetic semiconductor. Photo: Gan Molecules Illustration of the crystal structures derived from x-ray results and calculations. In ideal GaN (left), a Mn atom substitutes

448

Main Title 32pt  

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

Electroactive Ionic Liquids: Electroactive Ionic Liquids: A New Approach to Flow Batteries 2. Gallium Nitride Substrates for Power Electronics: Electrochemical Solution Growth Karen Waldrip, PhD Advanced Power Sources R&D Sandia National Labs, Albuquerque, NM knwaldr@sandia.gov Sandia National Laboratories' Programs Electroactive Ionic Liquids: A New Approach To Flow Batteries Date Travis Anderson David Ingersoll Chad Staiger Karen Waldrip Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. Flow Batteries *No cross contamination *Flexible layout *High cycle life *Large, tunable capacity *Low maintenance vanadium redox couples are

449

Page not found | Department of Energy  

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

21 - 13730 of 26,764 results. 21 - 13730 of 26,764 results. Download CX-010974: Categorical Exclusion Determination Advanced Low-Cost Silicon Carbide (SiC) and Gallium Nitride (GaN) Wide Bandgap Inverters for Under-the-Hood Electric Vehicle Traction... CX(s) Applied: B3.6 Date: 09/16/2013 Location(s): Arkansas Offices(s): National Energy Technology Laboratory http://energy.gov/nepa/downloads/cx-010974-categorical-exclusion-determination Download CX-010975: Categorical Exclusion Determination Advanced Climate Control and Cabin Preconditioning using Zonal Distribution, Advanced Heat Pump... CX(s) Applied: B3.6, B5.1 Date: 09/16/2013 Location(s): Michigan Offices(s): National Energy Technology Laboratory http://energy.gov/nepa/downloads/cx-010975-categorical-exclusion-determination Download CX-010976: Categorical Exclusion Determination

450

Cree Inc | Open Energy Information  

Open Energy Info (EERE)

Cree Inc Cree Inc Jump to: navigation, search Name Cree Inc Place Durham, North Carolina Zip 27703 Product Cree develops and manufactures semiconductor materials and devices based on silicon carbide (SiC), gallium nitride (GaN), silicon (Si) and related compounds. Coordinates 45.396265°, -122.755099° 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":45.396265,"lon":-122.755099,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

451

U.S. DEPARTIVmNT OF ENFRGY EERE PROJECT MANAGEMENT CENTER NEP.A DETFmllNATION  

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

DEPARTIVmNT OF ENFRGY DEPARTIVmNT OF ENFRGY EERE PROJECT MANAGEMENT CENTER NEP.A DETFmllNATION RECIPIENT:MEMC Electronic Materials, Inc. Page 1 of2 STATE: MO PROJECT TITLE: High Quality, Low Cost Bulk Gallium Nitride (GaN) Substrates Grown by the Electrochemical Solution Growth Method Funding Opportunity Announcement Number DE-FOA-0000560 Procurement Instrument Number NEPA Control Number CID Number DE-EE0005755 GF0-0005755-001 G05755 Based on my r eview of the information concerning the proposed action, as NEPA Compliance Officer (authorized under DOE Order 451.1A), I have made the following determination: CX, EA, EIS APPENDIX AND NUMBER: Description: A9 Information gathering, analysis, and dissemination Information gathering (including, but not limited to, literature surveys, inventories, site visits, and

452

Page not found | Department of Energy  

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

41 - 8950 of 29,416 results. 41 - 8950 of 29,416 results. Download CX-000845: Categorical Exclusion Determination 25A2445 - Ammonothermal Bulk Gallium Nitride (GaN) Crystal Growth for Energy Efficient Lighting CX(s) Applied: B3.6 Date: 01/15/2010 Location(s): New York Office(s): Advanced Research Projects Agency - Energy http://energy.gov/nepa/downloads/cx-000845-categorical-exclusion-determination Download CX-000839: Categorical Exclusion Determination 25A1089 - Electroville: High-Amperage Energy Storage Device-Energy Storage for the Neighborhood CX(s) Applied: B3.6 Date: 01/15/2010 Location(s): Massachusetts Office(s): Advanced Research Projects Agency - Energy http://energy.gov/nepa/downloads/cx-000839-categorical-exclusion-determination Download CX-000860: Categorical Exclusion Determination

453

STATEMENT OF CONSIDERATIONS  

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

331, 331, W(A} 2010·047, CH-1569 The Petitioner, Applied Materials, Inc., (Applied) was awarded the subject cooperative agreement with DOE for the performance of work entitled, "Recovery Act: Advanced Epi Tools for Gallium Nitride Light Emitting Diode Devices." The objective of the work is to achieve cost reduction of solid-state lighting (SSL) through improvements in manufacturing equipment, processes, and techniques. The primary objectives of the program are to reduce energy use and resulting pollutants by encouraging the adoption and installation of improved solid-state lighting products and to bolster the US manufacturing and technology base for related technologies. The program will support advanced manufacturing of LEOs to make SSL a more competitive

454

Development of a Bulk GaN Growth Technique for Low Defect Density, Large-Area Native Substrates  

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

Next-Generation Power Electronics: Next-Generation Power Electronics: Electrochemical Solution Growth (ESG) Technique for Bulk Gallium Nitride Substrates Karen Waldrip Dept. 2546, Advanced Power Sources R&D Sandia National Labs, Albuquerque, NM knwaldr@sandia.gov, (505) 844-1619 Acknowledgements: Mike Soboroff, Stan Atcitty, Nancy Clark, and John Boyes David Ingersoll, Frank Delnick, and Travis Anderson 2010 DOE Peer Review, Nov. 2-4, Washington, DC Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. Funded by the Energy Storage Systems Program of the U.S. Department Of Energy through Sandia National Laboratories Project Objective

455

Categorical Exclusion (CX) Determinations By Date | Department of Energy  

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

5, 2010 5, 2010 CX-006103: Categorical Exclusion Determination California-City-San Clemente CX(s) Applied: A1, A9, A11, B1.32, B5.1 Date: 03/05/2010 Location(s): San Clemente, California Office(s): Energy Efficiency and Renewable Energy March 5, 2010 CX-001054: Categorical Exclusion Determination Aquantis 2.5 Megawatt Ocean Current Generation Device CX(s) Applied: A9, B3.6 Date: 03/05/2010 Location(s): California Office(s): Energy Efficiency and Renewable Energy, Golden Field Office March 5, 2010 CX-001137: Categorical Exclusion Determination Advanced Epi Tools for Gallium Nitride LED (Light Emitting Diode) Devices CX(s) Applied: B3.6 Date: 03/05/2010 Location(s): Santa Clara, California Office(s): Energy Efficiency and Renewable Energy, National Energy Technology Laboratory

456

CX-004937: Categorical Exclusion Determination | Department of Energy  

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

937: Categorical Exclusion Determination 937: Categorical Exclusion Determination CX-004937: Categorical Exclusion Determination Transphorm, Inc. -High Performance Gallium Nitride High Electron Mobility Transistor Modules for Agile Power Electronics CX(s) Applied: B3.6 Date: 08/05/2010 Location(s): California Office(s): Advanced Research Projects Agency - Energy Funding will support laboratory research, design, testing, and fabrication of the first hybrid multichip power modules for inverters/converters operating at 1 megahertz, capable of being retrofitted to older generation motors, embedded in new motors, and in grid-tied photovoltaic inverters. The proposed work is consistent with the goal of Agile Delivery of Electric Power Technology (ADEPT): fundamental advances in soft magnetics, high voltage switches, and reliable, high-density charge storage. Proposed work

457

Categorical Exclusion (CX) Determinations By Date | Department of Energy  

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

5, 2010 5, 2010 CX-000839: Categorical Exclusion Determination 25A1089 - Electroville: High-Amperage Energy Storage Device-Energy Storage for the Neighborhood CX(s) Applied: B3.6 Date: 01/15/2010 Location(s): Massachusetts Office(s): Advanced Research Projects Agency - Energy January 15, 2010 CX-000845: Categorical Exclusion Determination 25A2445 - Ammonothermal Bulk Gallium Nitride (GaN) Crystal Growth for Energy Efficient Lighting CX(s) Applied: B3.6 Date: 01/15/2010 Location(s): New York Office(s): Advanced Research Projects Agency - Energy January 15, 2010 CX-000852: Categorical Exclusion Determination 25A4800 - High Energy Permanent Magnets for Hybrid Vehicles and Alternative Energy CX(s) Applied: B3.6 Date: 01/15/2010 Location(s): Delaware Office(s): Advanced Research Projects Agency - Energy

458

Page not found | Department of Energy  

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

61 - 15470 of 31,917 results. 61 - 15470 of 31,917 results. Download CX-004937: Categorical Exclusion Determination Transphorm, Inc. -High Performance Gallium Nitride High Electron Mobility Transistor Modules for Agile Power Electronics CX(s) Applied: B3.6 Date: 08/05/2010 Location(s): California Office(s): Advanced Research Projects Agency - Energy http://energy.gov/nepa/downloads/cx-004937-categorical-exclusion-determination Download Federal Register Notice for January 2012 Meeting Federal Register Notice for January 2012 URTAC Meeting http://energy.gov/fe/downloads/federal-register-notice-january-2012-meeting Download TBH-0080- In the Matter of Billy Joe Baptist This decision will consider an Order to Show Cause that I issued on February 3, 2009, regarding a March 6, 2008, whistleblower complaint filed

459

Power electronics reliability.  

Science Conference Proceedings (OSTI)

The project's goals are: (1) use experiments and modeling to investigate and characterize stress-related failure modes of post-silicon power electronic (PE) devices such as silicon carbide (SiC) and gallium nitride (GaN) switches; and (2) seek opportunities for condition monitoring (CM) and prognostics and health management (PHM) to further enhance the reliability of power electronics devices and equipment. CM - detect anomalies and diagnose problems that require maintenance. PHM - track damage growth, predict time to failure, and manage subsequent maintenance and operations in such a way to optimize overall system utility against cost. The benefits of CM/PHM are: (1) operate power conversion systems in ways that will preclude predicted failures; (2) reduce unscheduled downtime and thereby reduce costs; and (3) pioneering reliability in SiC and GaN.

Kaplar, Robert James; Brock, Reinhard C.; Marinella, Matthew; King, Michael Patrick; Stanley, James K.; Smith, Mark A.; Atcitty, Stanley

2010-10-01T23:59:59.000Z

460

Efficient Switches for Solar Power Conversion: Four Quadrant GaN Switch Enabled Three Phase Grid-Tied Microinverters  

Science Conference Proceedings (OSTI)

Solar ADEPT Project: Transphorm is developing power switches for new types of inverters that improve the efficiency and reliability of converting energy from solar panels into useable electricity for the grid. Transistors act as fast switches and control the electrical energy that flows in an electrical circuit. Turning a transistor off opens the circuit and stops the flow of electrical current; turning it on closes the circuit and allows electrical current to flow. In this way a transistor can be used to convert DC from a solar panel into AC for use in a home. Transphorm’s transistors will enable a single semiconductor device to switch electrical currents at high-voltage in both directions—making the inverter more compact and reliable. Transphorm is using Gallium Nitride (GaN) as a semiconductor material in its transistors instead of silicon, which is used in most conventional transistors, because GaN transistors have lower losses at higher voltages and switching frequencies.

None

2012-02-13T23:59:59.000Z

Note: This page contains sample records for the topic "gallium nitride ingan" 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

Chip-Scale Power Conversion for LED Lighting: Integrated Power Chip Converter for Solid-State Lighting  

Science Conference Proceedings (OSTI)

ADEPT Project: Teledyne is developing cost-effective power drivers for energy-efficient LED lights that fit on a compact chip. These power drivers are important because they transmit power throughout the LED device. Traditional LED driver components waste energy and don't last as long as the LED itself. They are also large and bulky, so they must be assembled onto a circuit board separately which increases the overall manufacturing cost of the LED light. Teledyne is shrinking the size and improving the efficiency of its LED driver components by using thin layers of an iron magnetic alloy and new gallium nitride on silicon devices. Smaller, more efficient components will enable the drivers to be integrated on a single chip, reducing costs. The new semiconductors in Teledyne's drivers can also handle higher levels of power and last longer without sacrificing efficiency. Initial applications for Teledyne's LED power drivers include refrigerated grocery display cases and retail lighting.

None

2010-10-01T23:59:59.000Z

462

Stress testing on silicon carbide electronic devices for prognostics and health management.  

SciTech Connect

Power conversion systems for energy storage and other distributed energy resource applications are among the drivers of the important role that power electronics plays in providing reliable electricity. Wide band gap semiconductors such as silicon carbide (SiC) and gallium nitride (GaN) will help increase the performance and efficiency of power electronic equipment while condition monitoring (CM) and prognostics and health management (PHM) will increase the operational availability of the equipment and thereby make it more cost effective. Voltage and/or temperature stress testing were performed on a number of SiC devices in order to accelerate failure modes and to identify measureable shifts in electrical characteristics which may provide early indication of those failures. Those shifts can be interpreted and modeled to provide prognostic signatures for use in CM and/or PHM. Such experiments will also lead to a deeper understanding of basic device physics and the degradation mechanisms behind failure.

Kaplar, Robert James; Brock, Reinhard C.; Marinella, Matthew; King, Michael Patrick; Smith, Mark A.; Atcitty, Stanley

2011-01-01T23:59:59.000Z

463

InGaAsN/GaAs heterojunction for multi-junction solar cells  

DOE Patents (OSTI)

An InGaAsN/GaAs semiconductor p-n heterojunction is disclosed for use in forming a 0.95-1.2 eV bandgap photodetector with application for use in high-efficiency multi-junction solar cells. The InGaAsN/GaAs p-n heterojunction is formed by epitaxially growing on a gallium arsenide (GaAs) or germanium (Ge) substrate an n-type indium gallium arsenide nitride (InGaAsN) layer having a semiconductor alloy composition In.sub.x Ga.sub.1-x As.sub.1-y N.sub.y with 070%.

Kurtz, Steven R. (Albuquerque, NM); Allerman, Andrew A. (Albuquerque, NM); Klem, John F. (Albuquerque, NM); Jones, Eric D. (Edgewood, NM)

2001-01-01T23:59:59.000Z

464

Techniques for Growth of Lattice-Matched Semiconductor Layers ...  

As one example, the technologies can be used to grow lattice-matched InGaN alloys for fabrication of a green LED.

465

High Efficiency LED Lamp for Solid-State Lighting  

SciTech Connect

This report contains a summary of technical achievements during a three-year project to demonstrate high efficiency, solid-state lamps based on gallium nitride/silicon carbide light-emitting diodes. Novel chip designs and fabrication processes are described for a new type of nitride light-emitting diode with the potential for very high efficiency. This work resulted in the demonstration of blue light-emitting diodes in the one watt class that achieved up to 495 mW of light output at 350 mA drive current, corresponding to quantum and wall plug efficiencies of 51% and 45%, respectively. When combined with a phosphor in Cree's 7090 XLamp package, these advanced blue-emitting devices resulted in white light-emitting diodes whose efficacy exceeded 85 lumens per watt. In addition, up to 1040 lumens at greater than 85 lumens per watt was achieved by combining multiple devices to make a compact white lamp module with high optical efficiency.

James Ibbetson

2006-12-31T23:59:59.000Z

466

Single-Crystalline Thin Film Used in Photovoltaics  

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

Single-crystalline thin films are made from gallium arsenide (GaAs), a compound semiconductor that is a mixture of gallium and arsenic.

467

Bismuth in gallium arsenide: Structural and electronic properties of GaAs{sub 1-x}Bi{sub x} alloys  

Science Conference Proceedings (OSTI)

The structural and electronic properties of cubic GaAs{sub 1-x}Bi{sub x} alloys with bismuth concentration 0.0, 0.25, 0.50, 0.75 and 1.0 are studied using the 'special quasi-random structures' (SQS) approach of Zunger along with the generalized gradient approximation (GGA) and the Engel-Vosko generalized gradient approximation (EV-GGA). The lattice constant, bulk modulus, derivative of bulk modulus and energy gap vary with bismuth concentration nonlinearly. The present calculations show that the band gap decreases substantially with increasing bismuth concentration and that spin-orbit coupling influences the nature of bonding at high Bi concentrations. - Graphical abstract: Bowing effect of spin-orbit split-off band values versus Bi content with and without spin-orbit coupling for GaAs{sub 1-x}Bi{sub x} (at x=0.25, 0.50 and 0.75). Calculations are done with GGA. Highlights: Black-Right-Pointing-Pointer Structural and electronic properties of GaAs{sub 1-x}Bi{sub x} alloys were studied. Black-Right-Pointing-Pointer We present results of lattice constant, energy gap, bulk modulus and derivative. Black-Right-Pointing-Pointer The band gap decreases substantially with increasing Bi concentration. Black-Right-Pointing-Pointer Calculations of the density of states and charge densities are also presented. Black-Right-Pointing-Pointer We have performed calculations without and with spin-orbit coupling.

Reshak, Ali Hussain, E-mail: maalidph@yahoo.co.uk [School of Complex Systems, FFWP-South Bohemia University, Nove Hrady 37333 (Czech Republic); School of Material Engineering, Malaysia University of Perlis, P.O Box 77, d/a Pejabat Pos Besar, 01007 Kangar, Perlis (Malaysia); Kamarudin, H. [School of Material Engineering, Malaysia University of Perlis, P.O Box 77, d/a Pejabat Pos Besar, 01007 Kangar, Perlis (Malaysia); Auluck, S. [National Physical Laboratory Dr. KS Krishnan Marg, New Delhi 110012 (India); Kityk, I.V. [Electrical Engineering Department, Technological University of Czestochowa, Al. Armii Krajowej 17/19, Czestochowa (Poland)

2012-02-15T23:59:59.000Z

468

High temperature step-flow growth of gallium phosphide by molecular beam epitaxy and metalorganic chemical vapor deposition  

Science Conference Proceedings (OSTI)

Post-growth surface morphologies of high-temperature homoepitaxial GaP films grown by molecular beam epitaxy (MBE) and metalorganic chemical vapor deposition (MOCVD) have been studied. Smooth, stepped surface morphologies of MBE-grown layers, measured by atomic force microscopy, were found for a wide range of substrate temperatures and P{sub 2}:Ga flux ratios. A MOCVD-based growth study performed under similar conditions to MBE-grown samples shows a nearly identical smooth, step-flow surface morphology, presenting a convergence of growth conditions for the two different methods. The additional understanding of GaP epitaxy gained from this study will impact its use in applications that include GaP-based device technologies, III-V metamorphic buffers, and III-V materials integration with silicon.

Ratcliff, C. [Department of Electrical and Computer Engineering, Ohio State University, Columbus, Ohio 43210 (United States); Grassman, T. J.; Ringel, S. A. [Department of Electrical and Computer Engineering, Ohio State University, Columbus, Ohio 43210 (United States); Institute for Materials Research, Ohio State University, Columbus, Ohio 43210 (United States); Carlin, J. A. [Institute for Materials Research, Ohio State University, Columbus, Ohio 43210 (United States)

2011-10-03T23:59:59.000Z

469

Förster Resonance Energy Transfer Mediated White-Light-Emitting Rhodamine Fluorophore Derivatives-Gamma Phase Gallium Oxide Nanostructures.  

E-Print Network (OSTI)

??The global lighting source energy consumption accounts for about 22% of the total electricity generated. New high-efficiency solid-state light sources are needed to reduce the… (more)

Chiu, Wan Hang Melanie

2012-01-01T23:59:59.000Z

470

Electron-beam induced electric-hydraulic expansion in a silica-shelled gallium microball-nanotube structure  

Science Conference Proceedings (OSTI)

Heteroshape-heteroscale structure of silica-shelled Ga microball-nanotube was fabricated. Under in situ electron-beam irradiation, an abnormally large and fast expansion of Ga was observed. Failed by a sole routine heating effect of electron-beam, the expansion was explained by an electric-hydraulic expansion effect taking into account a huge inner pressure induced by the repelling Coulomb force of positively charged Ga ions on the Ga microball surface. The ions were accumulated due to knocking-out of Ga electrons under irradiation and shielding effect of a silica shell which prevents the charge balance restoration. A circuit model is proposed to calculate the accumulation of Ga ions.

Gao, Y. H.; Sun, M.; Su, J. [Wuhan National Laboratory for Optoelectronics (WNLO), School of Physics, College of Optoelectronic Science and Engineering, Huazhong University of Science and Technology (HUST), LuoyuRoad 1037, Wuhan 430074 (China); Zhi, C. Y.; Golberg, D.; Bando, Y. [International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), Namiki 1-1, Tsukuba, Ibaraki 305-0044 (Japan); Duan, X. F. [Institute of Physics, Beijing National Laboratory of Condensed Matter Physics, Chinese Academy of Sciences