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1

Mexico FL GA SC AL MS LA TX AR TN TN  

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

2005 Hurricanes on the Natural Gas Industry in the Gulf of Mexico Region Mexico FL GA SC AL MS LA TX AR TN TN Katrina - Cumulative wind > 39 mph Katrina - Cumulative wind > 73 mph...

2

REPLY TO Al-TN OF: EM-421 SUBJECT:  

Office of Legacy Management (LM)

;;;;!r;; c"/ I%- , 2.1 + 2- ;;;;!r;; c"/ I%- , 2.1 + 2- llnited States Government Department of Energy memorandum Fw?fw --&a Gt3 .I\ DATE: Af'R 8 1991 REPLY TO Al-TN OF: EM-421 SUBJECT: Elimination of the Magnus Brass Manufacturing Company from FUSRAP TO: The File The Magnus Brass Manufacturing Company Sites are hereby eliminated from consideration in the Department of Energy's Formerly Utilized Sites Remedial Action Program (FUSRAP). The Department of Energy does not have the authority under the Atomic Energy Act to further investigate the sites, which are located at 533 Reading Road and 1029 West Seventh Street in Cincinnati, Ohio. The lack of authority is more fully explained in the attached Authority Review. The Department of Energy does not have any further information concerning the radiological status of the sites;

3

AlGaN/GaN-based power semiconductor switches  

E-Print Network (OSTI)

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

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

2013-01-01T23:59:59.000Z

4

REPLY TO AlTN OF: W-421 (W. A. W  

Office of Legacy Management (LM)

QOEF 13254 QOEF 13254 i.3891 EFG iO7W United- states Government bemoranduin DATE: f-!uG 3, 9 19g4 REPLY TO AlTN OF: W-421 (W. A. W illiams, 427-1719) SUBJECT: Elimination of the Sites from Program the Formerly Utilized Sites Remedial Action To' The File In 1990, with the assistance of Mr. reviewed a number of sites that had services to the Fernald facility as . _ Doug Tonkay and Us. Michelle Landis, I formerly provided goods and/or subcontractors. For 24 of .these B. . sites, recoaaaendations were made to ellrlnate them from further consideration under Fomerly Utilized Sites Remedial Action Program (FUSRAP). In each case, I made or reviewed the evaluation, and, in each case, a handwritten evaluation was prepared. This is to provide a more formal record of the decision on these sites and to ratify and confirm the

5

Effect of dislocations on electron mobility in AlGaN/GaN and AlGaN/AlN/GaN heterostructures  

Science Conference Proceedings (OSTI)

Al{sub x}Ga{sub 1-x}N/GaN (x = 0.06, 0.12, 0.24) and AlGaN/AlN/GaN heterostructures were grown on 6 H-SiC, GaN-on-sapphire, and free-standing GaN, resulting in heterostructures with threading dislocation densities of {approx}2 Multiplication-Sign 10{sup 10}, {approx}5 Multiplication-Sign 10{sup 8}, and {approx}5 Multiplication-Sign 10{sup 7} cm{sup -2}, respectively. All growths were performed under Ga-rich conditions by plasma-assisted molecular beam epitaxy. Dominant scattering mechanisms with variations in threading dislocation density and sheet concentration were indicated through temperature-dependent Hall measurements. The inclusion of an AlN interlayer was also considered. Dislocation scattering contributed to reduced mobility in these heterostructures, especially when sheet concentration was low or when an AlN interlayer was present.

Kaun, Stephen W.; Burke, Peter G.; Kyle, Erin C. H.; Speck, James S. [Materials Department, University of California, Santa Barbara, California 93106 (United States); Wong, Man Hoi; Mishra, Umesh K. [Electrical and Computer Engineering Department, University of California, Santa Barbara, California 93106 (United States)

2012-12-24T23:59:59.000Z

6

GA-AL-SC | Department of Energy  

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

GA-AL-SC GA-AL-SC GA-AL-SC October 1, 2012 ALA-1-N Wholesale Power Rate Schedule Area: PowerSouth Energy Cooperative System: Georgia-Alabama-South Carolina October 1, 2012 Duke-1-E Wholesale Power Rate Schedule Area: Duke On-System System: Georgia-Alabama-South Carolina October 1, 2012 Duke-2-E Wholesale Power Rate Schedule Area: Central System: Georgia-Alabama-South Carolina October 1, 2012 Duke-3-E Wholesale Power Rate Schedule Area: None System: Georgia-Alabama-South Carolina October 1, 2012 Duke-4-E Wholesale Power Rate Schedule Area: Duke Self-Schedulers System: Georgia-Alabama-South Carolina October 1, 2012 MISS-1-N Wholesale Power Rate Schedule Area: South Mississippi Electric Power Association System: Georgia-Alabama-South Carolina October 1, 2012 Pump-1-A Wholesale Power Rate Schedule

7

Ultraviolet electroabsorption modulator based on AlGaN/GaN multiple quantum wells  

E-Print Network (OSTI)

Ultraviolet electroabsorption modulator based on AlGaN/GaN multiple quantum wells I. Friel, C online 20 June 2005 An ultraviolet electroabsorption modulator based on AlGaN/GaN quantum wells is demonstrated. Enhanced excitonic absorption in the quantum wells at around 3.48 eV was achieved using

Moustakas, Theodore

8

Self-aligned AlGaN/GaN transistors for sub-mm wave applications  

E-Print Network (OSTI)

This thesis describes work done towards realizing self-aligned AlGaN/GaN high electron mobility transistors (HEMTs). Self-aligned transistors are important for improving the frequency of AlGaN/GaN HEMTs by reducing source ...

Saadat, Omair I

2010-01-01T23:59:59.000Z

9

Reactive codoping of GaAlInP compound semiconductors  

DOE Patents (OSTI)

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

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

2008-02-12T23:59:59.000Z

10

Characteristics study of 2DEG transport properties of AlGaN/GaN and AlGaAs/GaAs-based HEMT  

Science Conference Proceedings (OSTI)

Growth of wide bandgap material over narrow bandgap material, results into a two dimensional electron gas (2DEG) at the heterointerface due to the conduction band discontinuity. In this paper the 2DEG transport properties of AlGaN/GaN-based high electron mobility transistor (HEMT) is discussed and its effect on various characteristics such as 2DEG density, C-V characteristics and Sheet resistances for different mole fractions are presented. The obtained results are also compared with AlGaAs/GaAs-based HEMT for the same structural parameter as like AlGaN/GaN-based HEMT. The calculated results of electron sheet concentration as a function of the Al mole fraction are in excellent agreement with some experimental data available in the literature.

Lenka, T. R., E-mail: trlenka@gmail.com; Panda, A. K., E-mail: akpanda62@hotmail.com [National Institute of Science and Technology, Palur Hills (India)

2011-05-15T23:59:59.000Z

11

Effect of buffer structures on AlGaN/GaN high electron mobility transistor reliability  

Science Conference Proceedings (OSTI)

AlGaN/GaN high electron mobility transistors (HEMTs) with three different types of buffer layers, including a GaN/AlGaN composite layer, or 1 or 2 lm GaN thick layers, were fabricated and their reliability compared. The HEMTs with the thick GaN buffer layer showed the lowest critical voltage (Vcri) during off-state drain step-stress, but this was increased by around 50% and 100% for devices with the composite AlGaN/GaN buffer layers or thinner GaN buffers, respectively. The Voff - state for HEMTs with thin GaN and composite buffers were 100 V, however, this degraded to 50 60V for devices with thick GaN buffers due to the difference in peak electric field near the gate edge. A similar trend was observed in the isolation breakdown voltage measurements, with the highest Viso achieved based on thin GaN or composite buffer designs (600 700 V), while a much smaller Viso of 200V was measured on HEMTs with the thick GaN buffer layers. These results demonstrate the strong influence of buffer structure and defect density on AlGaN/GaN HEMT performance and reliability.

Liu, L. [University of Florida, Gainesville; Xi, Y. Y. [University of Florida, Gainesville; Ren, F. [University of Florida; Pearton, S. J. [University of Florida; Laboutin, O. [Kopin Corporation, Taunton, MA; Cao, Yu [Kopin Corporation, Taunton, MA; Johnson, Wayne J. [Kopin Corporation, Taunton, MA; Kravchenko, Ivan I [ORNL

2012-01-01T23:59:59.000Z

12

AlGaAsSb/GaSb Distributed Bragg Reflectors Grown by Organometallic Vapor Phase Epitaxy  

SciTech Connect

The first AlGaAsSb/GaSb quarter-wave distributed Bragg reflectors grown by metallic vapor phase epitaxy are reported. The peak reflectance is 96% for a 10-period structure.

C.A. Wang; C.J. Vineis; D.R. Calawa

2002-02-13T23:59:59.000Z

13

Molecular beam epitaxy growth of GaAsBi/GaAs/AlGaAs separate confinement heterostructures  

Science Conference Proceedings (OSTI)

GaAsBi/GaAs/AlGaAs separate confinement heterostructures are grown using an asymmetric temperature profile due to the low optimal growth temperature of GaAsBi; the bottom AlGaAs barrier is grown at 610 Degree-Sign C, while the GaAsBi quantum well and the top AlGaAs barrier are grown at 320 Degree-Sign C. Cross-sectional transmission electron microscopy and room temperature photoluminescence measurements indicate that this approach results in samples with excellent structural and optical properties. The high quality of the low temperature AlGaAs barrier is attributed to the presence of Bi on the surface as indicated by a (1 Multiplication-Sign 3) surface reconstruction persisting throughout the low temperature growth.

Fan Dongsheng; Yu Shuiqing [Department of Electrical Engineering, University of Arkansas, Fayetteville, Arkansas 72701 (United States); Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville, Arkansas 72701 (United States); Zeng Zhaoquan; Hu Xian; Dorogan, Vitaliy G.; Li Chen; Benamara, Mourad; Hawkridge, Michael E.; Mazur, Yuriy I.; Salamo, Gregory J. [Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville, Arkansas 72701 (United States); Johnson, Shane R. [School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, Arizona 85287-6206 (United States); Wang, Zhiming M. [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054 (China)

2012-10-29T23:59:59.000Z

14

Radiation Hard AlGaN Detectors and Imager  

Science Conference Proceedings (OSTI)

Radiation hardness of AlGaN photodiodes was tested using a 65 MeV proton beam with a total proton fluence of 3x10{sup 12} protons/cm{sup 2}. AlGaN Deep UV Photodiode have extremely high radiation hardness. These new devices have mission critical applications in high energy density physics (HEDP) and space explorations. These new devices satisfy radiation hardness requirements by NIF. NSTec is developing next generation AlGaN optoelectronics and imagers.

None

2012-05-01T23:59:59.000Z

15

Pulsed optically detected NMR of single GaAs/AlGaAs quantum wells  

E-Print Network (OSTI)

Pulsed optically detected NMR of single GaAs/AlGaAs quantum wells Marcus Eickhoff* and Dieter Suter, nanometer-sized quantum wells possible with excellent sensitivity and selectivity while avoiding.60.-k; 78.55.Cr; 78.67.De Keywords: ODNMR; Pulsed excitation; Quantum well; GaAs 1. Introduction Nuclear

Suter, Dieter

16

Optical injection and coherent control of a ballistic charge current in GaAsAlGaAs quantum wells  

E-Print Network (OSTI)

Optical injection and coherent control of a ballistic charge current in GaAs�AlGaAs quantum wells of Hache´ et al.,2,3 but in this article we report injection into the plane of GaAs/AlGaAs quantum wells specific to quantum wells. Although we expect the underlying physics of injection and control of currents

Sipe,J. E.

17

Free carrier accumulation at cubic AlGaN/GaN heterojunctions  

Science Conference Proceedings (OSTI)

Cubic Al{sub 0.3}Ga{sub 0.7}N/GaN heterostructures were grown by plasma-assisted molecular beam epitaxy on 3C-SiC (001) substrates. A profile of the electrostatic potential across the cubic-AlGaN/GaN heterojunction was obtained using electron holography in the transmission electron microscope. The experimental potential profile indicates that the unintentionally doped layers show n-type behavior and accumulation of free electrons at the interface with a density of 5.1 x 10{sup 11}/cm{sup 2}, about one order of magnitude less than in wurtzite AlGaN/GaN junctions. A combination of electron holography and cathodoluminescence measurements yields a conduction-to-valence band offset ratio of 5:1 for the cubic AlGaN/GaN interface, which also promotes the electron accumulation. Band diagram simulations show that the donor states in the AlGaN layer provide the positive charges that to a great extent balance the two-dimensional electron gas.

Wei, Q. Y.; Li, T.; Huang, J. Y.; Ponce, F. A. [Department of Physics, Arizona State University, Tempe, Arizona 85287-1504 (United States); Tschumak, E.; Zado, A.; As, D. J. [Department of Physics, Universitaet Paderborn, D-33098 Paderborn (Germany)

2012-04-02T23:59:59.000Z

18

Schottky-Drain Technology for AlGaN/GaN High-Electron Mobility Transistors  

E-Print Network (OSTI)

In this letter, we demonstrate 27% improvement in the buffer breakdown voltage of AlGaN/GaN high-electron mobility transistors (HEMTs) grown on Si substrate by using a new Schottky-drain contact technology. Schottky-drain ...

Lu, Bin

19

Phonon Knudsen flow in GaAs/AlAs superlattices  

DOE Green Energy (OSTI)

The measured in-plane thermal conductivity, {delta}{sub SL} of GaAs/AlAs superlattices with even moderate layer thicknesses are significantly smaller than the weighted average, {delta}{sub l} = 67 W/Km, of the bulk GaAs and AlAs conductivities. One expects a suppression of the thermal conductivity to that of an actual Al{sub 0.5}Ga{sub 0.5}As alloy when the thickness of the GaAs and AlAs layers approaches that of a single monolayer. However, the observed superlattice thermal conductivity remains suppressed even at layer thickness {approx_gt} 10 nm. The low thermal conductivities, and very high mobilities, make n-doped GaAs/AlAs superlattices attractive possibilities for thermoelectric devices. With Molecular-Beam-Epitaxial grown GaAs/AlAs superlattices one can expect the individual GaAs and AlAs layers to be extremely clean. Defect and/or alloy scattering is limited to be near the heterostructure interfaces. The authors estimate the room-temperature phonon mean-free-path to be 42 (22) nm for the longitudinal (transverse) mode and thus comparable to or smaller than the layer thicknesses. Thus they expect an important phonon scattering at the interfaces. They study this phonon scattering at the superlattice interfaces assuming a Knudsen flow characterized by diffusive scattering. The solid curve in the figure shows the Knudsen-flow theory estimated for the superlattice thermal conductivity which shows a significant reduction when the layer thickness is shorter than the estimated phonon mean free paths.

Hyldgaard, P.; Mahan, G.D. [Oak Ridge National Lab., TN (United States). Solid State Div.]|[Univ. of Tennessee, Knoxville, TN (United States). Dept. of Physics and Astronomy

1995-09-01T23:59:59.000Z

20

Two-dimensional electron gas in AlGaN/GaN heterostructures  

Science Conference Proceedings (OSTI)

The formation of a two-dimensional electron gas (2DEG) system by an AlGaN/GaN heterostructure has been further confirmed by measuring its electrical properties. The effect of persistent photoconductivity (PPC) has been observed and its unique features have been utilized to study the properties of 2DEG formed by the AlGaN/GaN heterointerface. Sharp electronic transitions from the first to the second subbands in the 2DEG channel have been observed by monitoring the 2DEG carrier mobility as a function of carrier concentration through the use of PPC. These results are expected to have significant implications on field-effect transistor and high electron mobility transistor applications based on the GaN system. {copyright} {ital 1997 American Vacuum Society.}

Li, J.Z.; Lin, J.Y.; Jiang, H.X. [Department of Physics, Kansas State University, Manhattan, Kansas 66506-2601 (United States)] [Department of Physics, Kansas State University, Manhattan, Kansas 66506-2601 (United States); Khan, M.A.; Chen, Q. [APA Optics, Inc., Blaine, Minnesota 55449 (United States)] [APA Optics, Inc., Blaine, Minnesota 55449 (United States)

1997-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "tn al ga" 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

Charge Profiling of the p-AlGaN Electron Blocking Layer in AlGaInN Light Emitting Diode Structures  

E-Print Network (OSTI)

Charge Profiling of the p-AlGaN Electron Blocking Layer in AlGaInN Light Emitting Diode Structures, U.S.A. ABSTRACT Characterization of operational AlGaInN heterostructure light emitting diodes (LEDs the device lifetime in a non-destructive mode. INTRODUCTION Group ­ III nitride light emitting diodes (LEDs

Wetzel, Christian M.

22

Analysis of Schottky gate electron tunneling in polarization induced AlGaN/GaN high electron mobility transistors  

Science Conference Proceedings (OSTI)

( gate=nickel)/(barrier=GaN/Al (y) Ga (1?y) N)/(buffer=GaN)/(substrate=SiC ) polarizationinduced high electron mobility transistors (PI-HEMTs) show promise for ultrahigh power microwave amplification. The polarization fields in these Ga-face

Lester F. Eastman

1999-01-01T23:59:59.000Z

23

AlP/GaP distributed Bragg reflectors  

SciTech Connect

Distributed Bragg reflectors with high reflectivity bands centered at wavelengths from 530 to 690 nm (green to red) based on AlP/GaP quarter-wave stacks are prepared on (001)GaP using gas-source molecular-beam epitaxy. Additionally, the complex refractive index of AlP is measured using spectroscopic ellipsometry within the range of 330-850 nm in order to facilitate an accurate reflector design. Structures consisting of 15 quarter-wave stacks reach a peak reflectance between 95% and 98%, depending on the spectral position of the maximum.

Emberger, Valentin; Hatami, Fariba; Ted Masselink, W. [Department of Physics, Humboldt-Universitaet zu Berlin, Newtonstrasse 15, D-12489 Berlin (Germany); Peters, Sven [Sentech Instruments GmbH, Schwarzschildstr. 2, 12489 Berlin (Germany)

2013-07-15T23:59:59.000Z

24

AlGaAs/GaAs nano-hetero-epitaxy on a patterned GaAs substrate by MBE  

SciTech Connect

An AlGaAs/GaAs resonant tunneling diode (RTD) with submicron size was fabricated on {l_brace}111{r_brace} oblique facets of GaAs with selective MBE. The method is based on the fact that a certain facet structure is formed on a patterned substrate in selective MBE because the growth rate depends strongly on the facet structure. The fabrication of a double-barrier structure was attempted on a {l_brace}111{r_brace}B facet. The current-voltage characteristics of the sample showed negative differential resistance at 77K demonstrating that we have achieved an RTD on a submicron facet.

Nishiwaki, T.; Yamaguchi, M.; Sawaki, N. [Department of Electronics, Nagoya University, Chikusa-ku, Nagoya, 464-8603 (Japan)

2007-04-10T23:59:59.000Z

25

Evolution of structural defects associated with electrical degradation in AlGaN/GaN high electron mobility transistors  

E-Print Network (OSTI)

We have investigated the surface morphology of electrically stressed AlGaN/GaN high electron mobility transistors using atomic force microscopy and scanning electron microscopy after removing the gate metallization by ...

Makaram, Prashanth

26

Enhancement-mode AlGaN/GaN HEMTs with high linearity fabricated by hydrogen plasma treatment  

E-Print Network (OSTI)

Enhancement-mode (E-mode) AlGaN/GaN high electron mobility transistors (HEMTs) are highly desirable for power and digital electronic circuits. Several technologies have been demonstrated in the last few years to fabricate ...

Palacios, Tomas

27

Advanced technologies for improving high frequency performance of AlGaN/GaN high electron mobility transistors  

E-Print Network (OSTI)

In this thesis, we have used a combination of physical analysis, numerical simulation and experimental work to identify and overcome some of the main challenges in AlGaN/GaN high electron mobility transistors (HEMTs) for ...

Chung, Jinwook W. (Jinwook Will)

2008-01-01T23:59:59.000Z

28

MBE growth of high electron mobility 2DEGs in AlGaN/GaN heterostructures controlled by RHEED  

Science Conference Proceedings (OSTI)

We have grown 2DEG AlGaN/GaN heterostructures by molecular beam epitaxy (MBE) with electron mobilities up to 21500 cm{sup 2}V{sup -1}s{sup -1} at 2 K. In-situ RHEED was applied to optimize different aspects of Ga-rich growth. This paper gives a compact overview of the experimental key aspects that significantly affect the low temperature electron mobility in AlGaN/GaN heterostructures. Growth at the transition towards Ga droplet formation produced the best results. A quantitative analysis of the magnetoresistance confirmes scattering at dislocations as the dominant scattering process at low temperature.

Broxtermann, D.; Sivis, M.; Malindretos, J.; Rizzi, A. [IV. physikalisches Institut, Georg-August-Universitaet Goettingen (Germany)

2012-03-15T23:59:59.000Z

29

Growth and Fabrication of GaN/AlGaN Heterojunction Bipolar Transistor  

SciTech Connect

A GaN/AlGaN heterojunction bipolar transistor structure with Mg doping in the base and Si Doping in the emitter and collector regions was grown by Metal Organic Chemical Vapor Deposition in c-axis Al(2)O(3). Secondary Ion Mass Spectrometry measurements showed no increase in the O concentration (2-3x10(18) cm(-3)) in the AlGaN emitter and fairly low levels of C (~4-5x10(17) cm (-3)) throughout the structure. Due to the non-ohmic behavior of the base contact at room temperature, the current gain of large area (~90 um diameter) devices was <3. Increasing the device operating temperature led to higher ionization fractions of the mg acceptors in the base, and current gains of ~10 were obtained at 300 degree C.

Abernathy, C.R.; Baca, A.G.; Cao, X.A.; Cho, H.; Dang, G.T.; Donovan, S.M.; Han, J.; Jung, K.B.; Pearton, S.J.; Ren, F.; Shul, R.J.; Willison, C.G.; Wilson, R.G.; Zhang, A.P.; Zhang, L

1999-03-16T23:59:59.000Z

30

AlGaAs diode pumped tunable chromium lasers  

DOE Patents (OSTI)

An all-solid-state laser system is disclosed wherein the laser is pumped in the longwave wing of the pump absorption band. By utilizing a laser material that will accept unusually high dopant concentrations without deleterious effects on the crystal lattice one is able to compensate for the decreased cross section in the wing of the absorption band, and the number of pump sources which can be used with such a material increases correspondingly. In a particular embodiment a chromium doped colquiriite-structure crystal such as Cr:LiSrAlF.sub.6 is the laser material. The invention avoids the problems associated with using AlGaInP diodes by doping the Cr:LiSrAlF.sub.6 heavily to enable efficient pumping in the longwave wing of the absorption band with more practical AlGaAs diodes.

Krupke, William F. (Pleasanton, CA); Payne, Stephen A. (Castro Valley, CA)

1992-01-01T23:59:59.000Z

31

Evaluation of defects and degradation in GaAs-GaAlAs wafers using transmission cathodoluminescence  

Science Conference Proceedings (OSTI)

A large number of GaAs substrates GaAlAs double-heterostructure (DH) wafers, and high-radiance GaAlAs DH light-emitting diodes (LEDS) were evaluated using transmission cathodoluminescence (TCL). We show that only epitaxial wafers with a high defect density as revealed by TCL readily develop dark line defects (DLDs) with current injection, optical excitation, or electron beam excitation. Furthermore, in agreement with the previous work, the electron-beam-induced DLDs originate at dislocations and their growth requires minority-carrier injection. Based on these results, it is inferred that TCL can serve as a nondestructive screening technique for the selection of materials that produces a high yield of reliable LEDs.

Chin, A.K.; Keramidas, V.G.; Johnston, W.D. Jr.; Mahajan, S.; Roccasecca, D.D.

1980-02-01T23:59:59.000Z

32

Double pulse doped InGaAs/AlGaAs/GaAs pseudomorphic high-electron-mobility transistor heterostructures  

Science Conference Proceedings (OSTI)

Double pulse doped ({delta}-doped) InGaAs/AlGaAs/GaAs pseudomorphic high-electron-mobility transistor (HEMT) heterostructures were grown by molecular-beam epitaxy using a multiwafer technological system. The room-temperature electron mobility was determined by the Hall method as 6550 and 6000 cm{sup 2}/(V s) at sheet electron densities of 3.00 x 10{sup 12} and 3.36 x 10{sup 12} cm{sup -2}, respectively. HEMT heterostructures fabricated in a single process feature high uniformity of structural and electrical characteristics over the entire area of wafers 76.2 mm in diameter and high reproducibility of characteristics from process to process.

Egorov, A. Yu., E-mail: anton@beam.ioffe.ru; Gladyshev, A. G.; Nikitina, E. V.; Denisov, D. V.; Polyakov, N. K.; Pirogov, E. V.; Gorbazevich, A. A. [Russian Academy of Sciences, St. Petersburg Physics and Technology Center for Research and Education (Russian Federation)

2010-07-15T23:59:59.000Z

33

Mn-doped Ga(As,P) and (Al,Ga)As ferromagnetic semiconductors: Electronic structure calculations  

E-Print Network (OSTI)

A remarkable progress towards functional ferromagnetic semiconductor materials for spintronics has been achieved in p-type (Ga,Mn)As. Robust hole-mediated ferromagnetism has, however, been observed also in other III-V hosts such as antimonides, GaP, or (Al,Ga)As, which opens a wide area of possibilities for optimizing the host composition towards higher ferromagnetic Curie temperatures. Here we explore theoretically hole-mediated ferromagnetism and Mn incorporation in Ga(As,P) and (Al,Ga)As ternary hosts. While alloying (Ga,Mn)As with Al has only a small effect on the Curie temperature we predict a sizable enhancement of Curie temperatures in the smaller lattice constant Ga(As,P) hosts. Mn-doped Ga(As,P) is also favorable, as compared to (Al,Ga)As, with respect to the formation of carrier and moment compensating interstitial Mn impurities. In (Ga,Mn) (As,P) we find a marked decrease of the partial concentration of these detrimental impurities with increasing P content.

Masek, J.; Kudrnovsky, J.; Maca, F.; Sinova, Jairo; MacDonald, A. H.; Campion, R. P.; Gallagher, B. L.; Jungwirth, T.

2007-01-01T23:59:59.000Z

34

An inverted AlGaAs/GaAs patterned-Ge tunnel junction cascade concentrator solar cell  

DOE Green Energy (OSTI)

This report describes work to develop inverted-grown Al[sub 0.34]Ga[sub 0.66]As/GaAs cascades. Several significant developments are reported on as follows: (1) The AM1.5 1-sun total-area efficiency of the top Al[sub 0.34]Ga[sub 0.66]As cell for the cascade was improved from 11.3% to 13.2% (NREL measurement [total-area]). (2) The cycled'' organometallic vapor phase epitaxy growth (OMVPE) was studied in detail utilizing a combination of characterization techniques including Hall-data, photoluminescence, and secondary ion mass spectroscopy. (3) A technique called eutectic-metal-bonding (EMB) was developed by strain-free mounting of thin GaAs-AlGaAs films (based on lattice-matched growth on Ge substrates and selective plasma etching of Ge substrates) onto Si carrier substrates. Minority-carrier lifetime in an EMB GaAs double-heterostructure was measured as high as 103 nsec, the highest lifetime report for a freestanding GaAs thin film. (4) A thin-film, inverted-grown GaAs cell with a 1-sun AM1.5 active-area efficiency of 20.3% was obtained. This cell was eutectic-metal-bonded onto Si. (5) A thin-film inverted-grown, Al[sub 0.34]Ga[sub 0.66]As/GaAs cascade with AM1.5 efficiency of 19.9% and 21% at 1-sun and 7-suns, respectively, was obtained. This represents an important milestone in the development of an AlGaAs/GaAs cascade by OMVPE utilizing a tunnel interconnect and demonstrates a proof-of-concept for the inverted-growth approach.

Venkatasubramanian, R. (Research Triangle Inst., Research Triangle Park, NC (United States))

1993-01-01T23:59:59.000Z

35

High Breakdown ( > \\hbox {1500 V} ) AlGaN/GaN HEMTs by Substrate-Transfer Technology  

E-Print Network (OSTI)

In this letter, we present a new technology to increase the breakdown voltage of AlGaN/GaN high-electron-mobility transistors (HEMTs) grown on Si substrates. This new technology is based on the removal of the original Si ...

Lu, Bin

36

Fine structure of AlN/AlGaN superlattice grown by pulsed atomic-layer epitaxy for dislocation filtering  

SciTech Connect

We report the detailed structure analysis of our AlN/AlGaN superlattice (SL) grown by pulsed atomic-layer epitaxy (PALE) for dislocation filtering. Due to the nature of PALE, the AlGaN well material itself in the SL was found to be composed actually of an Al{sub x}Ga{sub 1-x}N/Al{sub y}Ga{sub 1-y}N short-period superlattice (SPSL), with the periodicity of 15.5 A ({approx_equal}6 monolayer), determined consistently from high-resolution x-ray diffraction and high-resolution transmission electron microscopy measurements. The SPSL nature of the AlGaN layers is believed to benefit from the AlN/AlGaN SL's coherent growth, which is important in exerting compressive strain for the thick upper n-AlGaN film, which serves to eliminate cracks. Direct evidence is presented which indicates that this SL can dramatically reduce the screw-type threading dislocation density.

Sun, W.H.; Zhang, J.P.; Yang, J.W.; Maruska, H.P.; Khan, M. Asif; Liu, R.; Ponce, F.A. [Department of Electrical Engineering, University of South Carolina, Columbia, South Carolina 29208 (United States); Department of Physics and Astronomy, Arizona State University, Tempe, Arizona 85287 (United States)

2005-11-21T23:59:59.000Z

37

M4, Semipolar AlGaN Buffers for Deep Ultraviolet Diode Lasers  

Science Conference Proceedings (OSTI)

On-axis reciprocal space mapping of the graded AlGaN showed tilt at each interface associated ..... New Concepts and Materials for Solar Power Conversion

38

Structure and Composition Peculiarities of GaN/AlN Multiple ...  

Science Conference Proceedings (OSTI)

Thickness of AlN and GaN layers in MQWs (multiple quantum wells) were ... InAs Quantum Dots by Ballistic Electron Emission Microscopy and Spectroscopy.

39

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

40

AlGaN/GaN high electron mobility transistors based on InGaN/GaN multi-quantum-well structures with photo-chemical vapor deposition of SiO2 dielectrics  

Science Conference Proceedings (OSTI)

AlGaN/GaN metal-oxide-semiconductor high electron mobility transistor (MOS-HEMT) based on InGaN/GaN multi-quantum-well (MQW) structure has been fabricated with SiO"2 dielectric deposited via photo-chemical vapor deposition (PHCVD) using a deuterium lamp ... Keywords: GaN, HEMT, MQW, Photo-chemical vapor deposition, SiO 2

Kai-Hsuan Lee; Ping-Chuan Chang; Shoou-Jinn Chang

2013-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "tn al ga" 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

Role of nanoscale AlN and InN for the microwave characteristics of AlGaN/(Al,In)N/GaN-based HEMT  

Science Conference Proceedings (OSTI)

A new AlGaN/GaN-based high electron mobility transistor (HEMT) is proposed and its micro-wave characteristics are discussed by introducing a nanoscale AlN or InN layer to study the potential improvement in their high frequency performance. The 2DEG transport mechanism including various sub-band calculations for both (Al,In) N-based HEMTs are also discussed in the paper. Apart from direct current characteristics of the proposed HEMT, various microwave parameters such as transconductance, unit current gain (h{sub 21} = 1) cut-off frequency (f{sub t}), high power-gain frequency (f{sub max}). Masons available/stable gain and masons unilateral gain are also discussed for both devices to understand its suitable deployment in microwave frequency range.

Lenka, T. R., E-mail: trlenka@gmail.com; Panda, A. K., E-mail: akpanda62@hotmail.com [National Institute of Science and Technology (India)

2011-09-15T23:59:59.000Z

42

GaSb/GaP compliant interface for high electron mobility AlSb/InAs heterostructures on (001) GaP  

Science Conference Proceedings (OSTI)

We report on the epitaxial growth of an AlSb/InAs heterostructure on a (001) GaP substrate. We investigate the conditions for the most efficient relaxation of GaSb islands on GaP. In particular, we show that the GaP surface treatment and the growth temperature are crucial for the formation of a two-dimensional periodic array of 90 deg. misfit dislocations at the episubstrate interface. With this relaxation process, an AlSb/InAs heterostructure exhibiting a room temperature mobility of 25 500 cm{sup 2} V{sup -1} s{sup -1} on GaP is demonstrated. This result paves the way to the integration of Sb-based devices on Si substrates through the use of GaP/Si templates.

El Kazzi, S.; Desplanque, L.; Coinon, C.; Wallart, X. [Institut d'Electronique, de Microelectronique, et de Nanotechnologie, UMR-CNRS 8520, BP 60069, 59652 Villeneuve d'Ascq Cedex (France); Wang, Y.; Ruterana, P. [CIMAP UMR 6252 CNRS-ENSICAEN-CEA-UCBN, 6, Boulevard du Marechal Juin, 14050 Caen Cedex (France)

2010-11-08T23:59:59.000Z

43

CC2, Two-Dimensional Electron Gas in In X Al 1-X N/Aln/GaN ...  

Science Conference Proceedings (OSTI)

DD3, A New Approach to Make ZnO-Cu2O Heterojunctions for Solar Cells ... E2, AlGaAs/GaAs/GaN Wafer Fused HBTs with Ar Implanted Extrinsic Collectors.

44

Temperature-Dependence of Exciton Radiative Recombination in (Al,Ga)N/GaN Quantum Wells Grown on a-Plane GaN Substrates  

E-Print Network (OSTI)

5221, 34095 Montpellier, France E-mail: pmc53@cam.ac.uk Received October 12, 2012; accepted November 22, 2012; published online May 20, 2013 This article presents the dynamics of excitons in a-plane (Al,Ga)N/GaN single quantum wells of various...

Corfdir, Pierre; Dussaigne, Amélie; Teisseyre, Henryk; Suski, Tadeusz; Grzegory, Izabella; Lefebvre, Pierre; Giraud, Etienne; Shahmohammadi, Mehran; Phillips, Richard; Ganičre, Jean-Daniel; Grandjean, Nicolas; Deveaud, Benoît

45

K7, Self-Assembled GaN/AlN Nanowire Superlattices on Si toward ...  

Science Conference Proceedings (OSTI)

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

46

Excitons in single and double GaAs/AlGaAs/ZnSe/Zn(Cd)MnSe heterovalent quantum wells  

Science Conference Proceedings (OSTI)

Exciton photoluminescence spectra, photoluminescence excitation spectra, and magnetophotoluminescence spectra of single (GaAs/AlGaAs/ZnMnSe) and double (GaAs/AlGaAs/ZnSe/ZnCdMnSe) heterovalent quantum wells formed by molecular beam epitaxy are studied. It is shown that the exciton absorption spectrum of such quantum wells mainly reproduces the resonant exciton spectrum expected for usual quantum wells with similar parameters, while the radiative exciton recombination have substantial distinctions, in particular the additional localization mechanism determined by defects generated by heterovalent interface exists. The nature of these localization centers is not currently clarified; their presence leads to broadening of photoluminescence lines and to an increase in the Stokes shift between the peaks of luminescence and absorption, as well as determining the variation in the magnetic g factor of bound exciton complexes.

Toropov, A. A., E-mail: toropov@beam.ioffe.ru; Kaibyshev, V. Kh.; Terent'ev, Ya. V.; Ivanov, S. V.; Kop'ev, P. S. [Russian Academy of Sciences, Ioffe Physical Technical Institute (Russian Federation)

2011-02-15T23:59:59.000Z

47

SnO2-gated AlGaN/GaN high electron mobility transistors based oxygen sensors  

Science Conference Proceedings (OSTI)

Hydrothermally grown SnO2 was integrated with AlGaN/GaN high electron mobility transistor (HEMT) sensor as the gate electrode for oxygen detection. The crystalline of the SnO2 was improved after annealing at 400 C. The grain growth kinetics of the SnO2 nanomaterials, together with the O2 gas sensing properties and sensing mechanism of the SnO2 gated HEMT sensors were investigated. Detection of 1% oxygen in nitrogen at 100 C was possible. A low operation temperature and low power consumption oxygen sensor can be achieved by combining the SnO2 films with the AlGaN/GaN HEMT structure

Hung, S.T. [Feng Chia University, Taichung, Taiwan; Chung, Chi-Jung [Feng Chia University, Taichung, Taiwan; Chen, Chin Ching [University of Florida, Gainesville; Lo, C. F. [University of Florida; Ren, F. [University of Florida; Pearton, S. J. [University of Florida; Kravchenko, Ivan I [ORNL

2012-01-01T23:59:59.000Z

48

Identification of the Parasitic Chemical Reactions during AlGaN OMVPE  

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

Identification of the Parasitic Chemical Reactions during AlGaN OMVPE Identification of the Parasitic Chemical Reactions during AlGaN OMVPE by J. R. Creighton, M. E. Coltrin, and W. G. Breiland Motivation-GaN and AlGaN alloys are ex- tremely important materials with widespread applications for optoelectronics (e.g. solid state lighting) and high power electronics. Or- ganometallic vapor phase epitaxy (OMVPE) is the primary deposition methodology, but it suf- fers from several growth chemistry anomalies. Growth rate and alloy composition are often a sensitive function of temperature and other reac- tor variables. These factors make the AlGaN OMVPE process difficult to control and in- crease the cost of the material. Conventional wisdom has been that the non-ideal OMVPE behavior is due to parasitic "pre-reactions" be-

49

Fabrication of Two-Dimensional Photonic Crystals in AlGaInP/GaInP Membranes by Inductively Coupled Plasma Etching  

E-Print Network (OSTI)

The fabrication process of two-dimensional photonic crystals in an AlGaInP/GaInP multi-quantum-well membrane structure is developed. The process includes high resolution electron-beam lithography, pattern transfer into ...

Chen, A.

50

Thermal carrier emission and nonradiative recombinations in nonpolar (Al,Ga)N/GaN quantum wells grown on bulk GaN  

Science Conference Proceedings (OSTI)

We investigate, via time-resolved photoluminescence, the temperature-dependence of charge carrier recombination mechanisms in nonpolar (Al,Ga)N/GaN single quantum wells (QWs) grown via molecular beam epitaxy on the a-facet of bulk GaN crystals. We study the influence of both QW width and barrier Al content on the dynamics of excitons in the 10-320 K range. We first show that the effective lifetime of QW excitons {tau} increases with temperature, which is evidence that nonradiative mechanisms do not play any significant role in the low-temperature range. The temperature range for increasing {tau} depends on the QW width and Al content in the (Al,Ga)N barriers. For higher temperatures, we observe a reduction in the QW emission lifetime combined with an increase in the decay time for excitons in the barriers, until both exciton populations get fully thermalized. Based on analysis of the ratio between barrier and QW emission intensities, we demonstrate that the main mechanism limiting the radiative efficiency in our set of samples is related to nonradiative recombination in the (Al,Ga)N barriers of charge carriers that have been thermally emitted from the QWs.

Corfdir, P.; Dussaigne, A.; Giraud, E.; Ganiere, J.-D.; Grandjean, N.; Deveaud-Pledran, B. [Institute of Condensed Matter Physics, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland); Teisseyre, H. [Institute of Physics, Polish Academy of Sciences, 02-668 Warsaw (Poland); Institute of High Pressure Physics, Polish Academy of Sciences, 01-142 Warsaw (Poland); Suski, T.; Grzegory, I. [Institute of High Pressure Physics, Polish Academy of Sciences, 01-142 Warsaw (Poland); Lefebvre, P. [Laboratoire Charles Coulomb - UMR5221 - CNRS - Universite Montpellier 2, 34095 Montpellier (France)

2012-02-01T23:59:59.000Z

51

Strain relaxation in GaN/Al{sub x}Ga{sub 1-x}N superlattices grown by plasma-assisted molecular-beam epitaxy  

SciTech Connect

We have investigated the misfit relaxation process in GaN/Al{sub x}Ga{sub 1-x}N (x = 0.1, 0.3, 0.44) superlattices (SL) deposited by plasma-assisted molecular beam epitaxy. The SLs under consideration were designed to achieve intersubband absorption in the mid-infrared spectral range. We have considered the case of growth on GaN (tensile stress) and on AlGaN (compressive stress) buffer layers, both deposited on GaN-on-sapphire templates. Using GaN buffer layers, the SL remains almost pseudomorphic for x = 0.1, 0.3, with edge-type threading dislocation densities below 9 x 10{sup 8} cm{sup -2} to 2 x 10{sup 9} cm{sup -2}. Increasing the Al mole fraction to 0.44, we observe an enhancement of misfit relaxation resulting in dislocation densities above 10{sup 10} cm{sup -2}. In the case of growth on AlGaN, strain relaxation is systematically stronger, with the corresponding increase in the dislocation density. In addition to the average relaxation trend of the SL, in situ measurements indicate a periodic fluctuation of the in-plane lattice parameter, which is explained by the different elastic response of the GaN and AlGaN surfaces to the Ga excess at the growth front. The results are compared with GaN/AlN SLs designed for near-infrared intersubband absorption.

Kotsar, Y.; Bellet-Amalric, E.; Das, A.; Monroy, E. [CEA-Grenoble, INAC/SP2M/NPSC, 17 Rue des Martyrs, 38054 Grenoble cedex 9 (France); Doisneau, B. [SIMaP, Grenoble INP, Domaine Universitaire, BP 75, 38402 Saint Martin d'Heres (France); Sarigiannidou, E. [LMGP, Grenoble INP, 3 Parvis Louis Neel, BP 257, 38016 Grenoble cedex 1 (France)

2011-08-01T23:59:59.000Z

52

AlGaAsSb buffer/barrier on GaAs substrate for InAs channel devices with high electron mobility and practical reliability  

Science Conference Proceedings (OSTI)

Keywords: AlGaAsSb, Hall elements, InAs, Sb, buffer/barriers, deep quantum well, field effect transistors, reliability

S. Miya; S. Muramatsu; N. Kuze; K. Nagase; T. Iwabuchi; A. Ichii; M. Ozaki; I. Shibasaki

1996-03-01T23:59:59.000Z

53

L1, Formation of Structural Defects in AlGaN/GaN High Electron ...  

Science Conference Proceedings (OSTI)

Transmission electron microscope (TEM) cross sectional image has shown that electrical degradation is closely related to structural damage in the GaN cap and  ...

54

Suppression of nuclear spin diffusion at a GaAs/AlGaAs interface measured with a single quantum dot nano-probe  

E-Print Network (OSTI)

Nuclear spin polarization dynamics are measured in optically pumped individual GaAs/AlGaAs interface quantum dots by detecting the time-dependence of the Overhauser shift in photoluminescence (PL) spectra. Long nuclear polarization decay times of ~ 1 minute have been found indicating inefficient nuclear spin diffusion from the GaAs dot into the surrounding AlGaAs matrix in externally applied magnetic field. A spin diffusion coefficient two orders lower than that previously found in bulk GaAs is deduced.

A. E. Nikolaenko; E. A. Chekhovich; M. N. Makhonin; I. W. Drouzas; A. B. Vankov; J. Skiba-Szymanska; M. S. Skolnick; P. Senellart; A. Lemaitre; A. I. Tartakovskii

2009-01-15T23:59:59.000Z

55

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

56

Metalorganic Vapor-Phase Epitaxial Growth and Characterization of Quaternary AlGaInN  

SciTech Connect

In this letter we report the growth (by MOVPE) and characterization of quaternary AlGaInN. A combination of PL, high-resolution XRD, and RBS characterizations enables us to explore and delineate the contours of equil-emission energy and lattice parameters as functions of the quaternary compositions. The observation of room temperature PL emission as short as 351nm (with 20% Al and 5% In) renders initial evidence that the quaternary could be used to provide confinement for GaInN (and possibly GaN). AlGaInN/GdnN MQW heterostructures have also been grown; both x-ray diffraction and PL measurement suggest the possibility of incorporating this quaternary into optoelectronic devices.

BANAS, MICHAEL ANTHONY; CRAWFORD, MARY H.; FIGIEL, JEFFREY J.; HAN, JUNG; LEE, STEPHEN R.; MYERS JR., SAMUEL M.; PETERSON, GARY D.

1999-09-27T23:59:59.000Z

57

Electroluminescence and Transmission Electron Microscopy Characterization of Reverse-Biased AlGaN/GaN Devices  

Science Conference Proceedings (OSTI)

Reverse-bias stress testing has been applied to a large set of more than 50 AlGaN/GaN high electron mobility transistors, which were fabricated using the same process but with different values of the AlN mole fraction and the AlGaN barrier-layer thickness, as well as different substrates (SiC and sapphire). Two sets of devices having different defect types and densities, related to the different growth conditions and the choice of nucleation layer, were also compared. When subjected to gate drain (or gate-to-drain and source short-circuited) reverse-bias testing, all devices presented the same time-dependent failure mode, consisting of a significant increase in the gate leakage current. This failure mechanism occurred abruptly during step-stress experiments when a certain negative gate voltage, or critical voltage, was exceeded or, during constant voltage tests, at a certain time, defined as time to breakdown. Electroluminescence (EL) microscopy was systematically used to identify localized damaged areas that induced an increase of gate reverse current. This current increase was correlated with the increase of EL intensity, and significant EL emission during tests occurred only when the critical voltage was exceeded. Focused-ion-beam milling produced cross-sectional samples suitable for electron microscopy observation at the sites of failure points previously identified by EL microscopy. In highdefectivity devices, V-defects were identified that were associated with initially high gate leakage current and corresponding to EL spots already present in untreated devices. Conversely, identification of defects induced by reverse-bias testing proved to be extremely difficult, and only nanometer-size cracks or defect chains, extending vertically from the gate edges through the AlGaN/GaN heterojunction, were found. No signs of metal/semiconductor interdiffusion or extended defective areas were visible.

Cullen, David A [ORNL; Smith, David J [Arizona State University; Passaseo, Adriana [Consiglio Nazionale delle Ricerche; Tasco, Vittorianna [Consiglio Nazionale delle Ricerche; Stocco, Antonio [Universita di Padova; Meneghini, Matteo [Universita di Padova; Meneghesso, Gaudenzio [Universita di Padova; Zanoni, Enrico [Universita di Padova

2013-01-01T23:59:59.000Z

58

NJ WY AK AL CA AR CO CT DE FL GA HI ID KS IL IN IA IA KY LA  

Gasoline and Diesel Fuel Update (EIA)

0.00-1.99 0.00-1.99 2.00-2.99 3.00-3.99 4.00-4.99 5.00-5.99 6.00-6.99 7.00+ NJ WY AK AL CA AR CO CT DE FL GA HI ID KS IL IN IA IA KY LA ME MI MA MD MN MS MT MO NE ND OH NV NM NY NH NC OK OR PA RI SC SD TN TX UT VT WA WV WI AZ VA DC 0.00-1.99 2.00-2.99 3.00-3.99 4.00-4.99 5.00-5.99 6.00-6.99 7.00+ 18. Average Price of Natural Gas Delivered to U.S. Onsystem Industrial Consumers, 1996 (Dollars per Thousand Cubic Feet) Figure 19. Average Price of Natural Gas Delivered to U.S. Electric Utilities, 1996 (Dollars per Thousand Cubic Feet) Figure Sources: Federal Energy Regulatory Commission (FERC), Form FERC-423, "Monthly Report of Cost and Quality of Fuels for Electric Plants," and Energy Information Administration (EIA), Form EIA-176, "Annual Report of Natural and Supplemental Gas Supply and Disposition." Note: In 1996, consumption of natural gas for agricultural use

59

GaAs/AlGaAs nanostructured composites for free-space and integrated optical devices  

E-Print Network (OSTI)

Fainman, "Influence of chlorine on etched sidewalls inFainman, “Influence of chlorine on etched sidewalls inthe RIBE of GaAs with chlorine (Cl 2 ), ion beam sputtering

Tsai, Chia-Ho

2006-01-01T23:59:59.000Z

60

Dependence on proton energy of degradation of AlGaN/GaN high electron mobility transistors  

Science Conference Proceedings (OSTI)

The effects of proton irradiation energy on dc, small signal, and large signal rf characteristics of AlGaN/GaN high electron mobility transistors (HEMTs) were investigated. AlGaN/GaN HEMTs were irradiated with protons at fixed fluence of 51015/cm2 and energies of 5, 10, and 15 MeV. Both dc and rf characteristics revealed more degradation at lower irradiation energy, with reductions of maximum transconductance of 11%, 22%, and 38%, and decreases in drain saturation current of 10%, 24%, and 46% for HEMTs exposed to 15, 10, and 5MeV protons, respectively. The increase in device degradation with decreasing proton energy is due to the increase in linear energy transfer and corresponding increase in nonionizing energy loss with decreasing proton energy in the active region of the HEMTs. After irradiation, both subthreshold drain leakage current and reverse gate current decreased more than 1 order of magnitude for all samples. The carrier removal rate was in the range 121 336 cm1 over the range of proton energies employed in this study

Liu, L. [University of Florida, Gainesville; Xi, Y. Y. [University of Florida, Gainesville; Wang, Y.l. [University of Florida; Ren, F. [University of Florida; Pearton, S. J. [University of Florida; Kim, H.-Y. [Korea University; Kim, J. [Korea University; Fitch, Robert C [Air Force Research Laboratory, Wright-Patterson AFB, OH; Walker, Dennis E [Air Force Research Laboratory, Wright-Patterson AFB, OH; Chabak, Kelson D [Air Force Research Laboratory, Wright-Patterson AFB, OH; Gillespie, James k [Air Force Research Laboratory, Wright-Patterson AFB, OH; Tetlak, Stephen E [Air Force Research Laboratory, Wright-Patterson AFB, OH; Via, Glen D [Air Force Research Laboratory, Wright-Patterson AFB, OH; Crespo, Antonio [Air Force Research Laboratory, Wright-Patterson AFB, OH; Kravchenko, Ivan I [ORNL

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "tn al ga" 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

Realization of compressively strained GaN films grown on Si(110) substrates by inserting a thin AlN/GaN superlattice interlayer  

Science Conference Proceedings (OSTI)

We investigate the strain properties of GaN films grown by plasma-assisted molecular beam epitaxy on Si(110) substrates. It is found that the strain of the GaN film can be converted from a tensile to a compressive state simply by inserting a thin AlN/GaN superlattice structure (SLs) within the GaN film. The GaN layers seperated by the SLs can have different strain states, which indicates that the SLs plays a key role in the strain modulation during the growth and the cooling down processes. Using this simple technique, we grow a crack-free GaN film exceeding 2-{mu}m-thick. The realization of the compressively strained GaN film makes it possible to grow thick GaN films without crack generation on Si substrates for optic and electronic device applications.

Shen, X. Q.; Takahashi, T.; Kawashima, H.; Ide, T.; Shimizu, M. [Advanced Power Electronics Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Umezono 1-1-1, Central 2, Tsukuba-shi, Ibaraki 305-8568 (Japan)

2012-07-16T23:59:59.000Z

62

Electron mobility and drift velocity in selectively doped InAlAs/InGaAs/InAlAs heterostructures  

Science Conference Proceedings (OSTI)

An increase in the electron mobility and drift velocity in high electric fields in quantum wells of selectively doped InAlAs/InGaAs/InAsAs heterostructures is obtained experimentally via controlling the composition of semiconductors forming the interface. The electron mobility at the interface in the In{sub 0.8}Ga{sub 0.2}As/In{sub 0.7}Al{sub 0.3}As metamorphic structure with a high molar fraction of In (0.7-0.8) is as high as 12.3 Multiplication-Sign 10{sup 3} cm{sup 2} V{sup -1} s{sup -1} at room temperature. An increase in the electron mobility by a factor of 1.1-1.4 is attained upon the introduction of thin (1-3 nm) InAs layers into a quantum well of selectively doped In{sub 0.53}Ga{sub 0.47}As/In{sub 0.52}Al{sub 0.48}As heterostructures. A maximal drift velocity attains 2.5 Multiplication-Sign 10{sup 7} cm/s in electric fields of 2-5 kV/cm. The threshold field F{sub th} for the intervalley {Gamma}-L electron transfer (the Gunn effect) in the InGaAs quantum well is higher than in the bulk material by a factor of 2.5-3. The effect of two- to threefold decrease in the threshold field F{sub th} in the InGaAs quantum well is established upon increasing the molar fraction of In in the InAlAs barrier, as well as upon the introduction of thin InAs inserts into the InGaAs quantum well.

Vasil'evskii, I. S., E-mail: pozela@pfi.lt; Galiev, G. B.; Klimov, E. A. [MEPHI National Nuclear Research University (Russian Federation); Pozela, K.; Pozela, J.; Juciene, V.; Suziedelis, A.; Zurauskiene, N.; Kersulis, S.; Stankevic, V. [Center for Physical Sciences and Technology, Semiconductor Physics Institute (Lithuania)

2011-09-15T23:59:59.000Z

63

Optical stability of shape-engineered InAs/InAlGaAs quantum dots  

SciTech Connect

The optical properties of shape-engineered InAs/InAlGaAs quantum dots (SEQDs) were investigated by temperature-dependent and excitation-power-dependent photoluminescence (PL) spectroscopy and compared with those of the conventionally grown InAs QDs (CQDs). The emission wavelength of the InAs/InAlGaAs SEQDs at 240 K was redshifted by 18 nm from that at 15 K, which was relatively smaller than that of the InAs CQDs (97 nm). The PL yield at 240 K was reduced to 1/86 and 1/65 of that measured at 15 K for the InAs CQDs and the InAs/InAlGaAs SEQDs, respectively. The emission wavelength for the InAs CQDs was blueshifted by 76 nm with increasing excitation power from 0.56 to 188 mW, compared to only by 7 nm for the InAs/InAlGaAs SEQDs. These results indicated that the InAs/InAlGaAs SEQDs were optically more stable than the InAs CQDs mainly due to the enhancement of the carrier confinement in the vertical direction and the improvement in the size uniformity.

Yang, Youngsin; Jo, Byounggu; Kim, Jaesu; Lee, Cheul-Ro; Kim, Jin Soo [Division of Advanced Materials Engineering, Research Center of Advanced Materials Development (RCAMD), Chonbuk National University, Jeonju, Chonbuk 561-756 (Korea, Republic of); Oh, Dae Kon [Electronics and Telecommunication Research Institute (ETRI), Daejeon 305-350 (Korea, Republic of); Kim, Jong Su [Advanced Photonics Research Institute, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of); Leem, Jae-Young [School of Nano Engineering, Inje University, Gimhae 621-749 (Korea, Republic of)

2009-03-01T23:59:59.000Z

64

An inverted AlGaAs/GaAs patterned-Ge tunnel junction cascade concentrator solar cell. Final subcontract report, 1 January 1991--31 August 1992  

DOE Green Energy (OSTI)

This report describes work to develop inverted-grown Al{sub 0.34}Ga{sub 0.66}As/GaAs cascades. Several significant developments are reported on as follows: (1) The AM1.5 1-sun total-area efficiency of the top Al{sub 0.34}Ga{sub 0.66}As cell for the cascade was improved from 11.3% to 13.2% (NREL measurement [total-area]). (2) The ``cycled`` organometallic vapor phase epitaxy growth (OMVPE) was studied in detail utilizing a combination of characterization techniques including Hall-data, photoluminescence, and secondary ion mass spectroscopy. (3) A technique called eutectic-metal-bonding (EMB) was developed by strain-free mounting of thin GaAs-AlGaAs films (based on lattice-matched growth on Ge substrates and selective plasma etching of Ge substrates) onto Si carrier substrates. Minority-carrier lifetime in an EMB GaAs double-heterostructure was measured as high as 103 nsec, the highest lifetime report for a freestanding GaAs thin film. (4) A thin-film, inverted-grown GaAs cell with a 1-sun AM1.5 active-area efficiency of 20.3% was obtained. This cell was eutectic-metal-bonded onto Si. (5) A thin-film inverted-grown, Al{sub 0.34}Ga{sub 0.66}As/GaAs cascade with AM1.5 efficiency of 19.9% and 21% at 1-sun and 7-suns, respectively, was obtained. This represents an important milestone in the development of an AlGaAs/GaAs cascade by OMVPE utilizing a tunnel interconnect and demonstrates a proof-of-concept for the inverted-growth approach.

Venkatasubramanian, R. [Research Triangle Inst., Research Triangle Park, NC (United States)

1993-01-01T23:59:59.000Z

65

Al composition dependence of breakdown voltage in Al{sub x}Ga{sub 1-x}N Schottky rectifiers  

SciTech Connect

Planar geometry, lateral Schottky rectifiers were fabricated on high resistivity Al{sub x}Ga{sub 1-x}N (x=0-0.25) epitaxial layers grown on sapphire substrates. The reverse breakdown voltages of unpassivated devices increased with Al composition, varying from 2.3 kV for GaN to 4.3 kV for Al{sub 0.25}Ga{sub 0.75}N. The reverse current-voltage (I-V) characteristics showed classical Shockley-Read-Hall recombination as the dominant mechanism, with I{proportional_to}V{sup 0.5}. The reverse current density in all diodes was in the range 5-10x10{sup -6} A cm{sup -2} at 2 kV. The use of p{sup +} guard rings was effective in preventing premature edge breakdown and with optimum ring width increased V{sub B} from 2.3 to 3.1 kV in GaN diodes. (c) 2000 American Institute of Physics.

Zhang, A. P. [Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611 (United States)] [Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611 (United States); Dang, G. [Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611 (United States)] [Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611 (United States); Ren, F. [Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611 (United States)] [Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611 (United States); Han, J. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States); Polyakov, A. Y. [Institute of Rare Metals, Moscow 109017, Russia (Russian Federation)] [Institute of Rare Metals, Moscow 109017, Russia (Russian Federation); Smirnov, N. B. [Institute of Rare Metals, Moscow 109017, Russia (Russian Federation)] [Institute of Rare Metals, Moscow 109017, Russia (Russian Federation); Govorkov, A. V. [Institute of Rare Metals, Moscow 109017, Russia (Russian Federation)] [Institute of Rare Metals, Moscow 109017, Russia (Russian Federation); Redwing, J. M. [Epitronics, Phoenix, Arizona 85027 (United States)] [Epitronics, Phoenix, Arizona 85027 (United States); Cao, X. A. [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States)] [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Pearton, S. J. [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States)] [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States)

2000-03-27T23:59:59.000Z

66

Optical modulation at around 1550 nm in a InGaAlAs optical waveguide containing a InGaAs/AlAs resonant tunnelling diode  

E-Print Network (OSTI)

We report electro-absorption modulation of light at around 1550 nm in a unipolar InGaAlAs optical waveguide containing a InGaAs/AlAs double-barrier resonant tunneling diode (DB-RTD). The RTD peak-to-valley transition increases the electric field across the waveguide, which shifts the core material absorption band-edge to longer wavelengths via the Franz-Keldysh effect, thus changing the light-guiding characteristics of the waveguide. Low-frequency characterisation of a device shows modulation up to 28 dB at 1565 nm. When dc biased close to the negative differential conductance (NDC) region, the RTD optical waveguide behaves as an electro-absorption modulator integrated with a wide bandwidth electrical amplifier, offering a potential advantage over conventional pn modulators.

Figueiredo, J M L; Stanley, C R; Ironside, C N; McMeekin, S G; Leite, A M P

1999-01-01T23:59:59.000Z

67

THz laser based on quasi-periodic AlGaAs superlattices  

SciTech Connect

The use of quasi-periodic AlGaAs superlattices as an active element of a quantum cascade laser of terahertz range is proposed and theoretically investigated. A multi-colour emission, having from three to six peaks of optical gain, is found in Fibonacci, Thue-Morse, and figurate superlattices in electric fields of intensity F = 11 - 13 kV cm{sup -1} in the frequency range f = 2 - 4 THz. The peaks depend linearly on the electric field, retain the height of 20 cm{sup -1}, and strongly depend on the thickness of the AlGaAs-layers. (lasers)

Malyshev, K V [N.E. Bauman Moscow State Technical University, Moscow (Russian Federation)

2013-06-30T23:59:59.000Z

68

Impact of proton irradiation on dc performance of AlGaN/GaN high electron mobility transistors  

Science Conference Proceedings (OSTI)

The effects of proton irradiation dose on dc characteristics and the reliability of AlGaN/GaN high electron mobility transistors (HEMTs) were investigated. The HEMTs were irradiated with protons at a fixed energy of 5 MeV and doses ranging from 109 to 2 1014 cm-2. For the dc characteristics, there was only minimal degradation of saturation drain current (IDSS), transconductance (gm), electron mobility and sheet carrier concentration at doses below 2 1013 cm-2, while the reduction of these parameters were 15%, 9%, 41% and 16.6%, respectively, at a dose of 2 1014 cm-2. At this same dose condition, increases of 37% in drain breakdown voltage (VBR) and of 45% in critical voltage (Vcri) were observed. The improvement of device reliability was attributed to the modification of the depletion region due to the introduction of a higher density of defects after irradiation at a higher dose.

Liu, L. [University of Florida, Gainesville; Cuervo, C.V. [University of Florida, Gainesville; Xi, Y. Y. [University of Florida, Gainesville; Ren, F. [University of Florida; Pearton, S. J. [University of Florida; Kim, H.-Y. [Korea University; Kim, J. [Korea University; Kravchenko, Ivan I [ORNL

2013-01-01T23:59:59.000Z

69

Harmonic Responses in 2DEG AlGaAs/GaAs HEMT Devices Due to Plasma Wave Interaction  

Science Conference Proceedings (OSTI)

Plasma waves are oscillations of electron density in time and space, and in deep submicron field effect transistors, typical plasma frequencies, omega{sub p}, lie in the terahertz range and do not involve any quantum transitions. Hence, using plasma wave excitation for detection and/or generation of THz oscillations is a very promising approach. In this paper, the investigation of plasma wave interaction between the plasma waves propagating in a short-channel High-Electron-Mobility Transistor (HEMT) and the radiated electromagnetic waves was carried out. Experimentally, we have demonstrated the detection of the terahertz (THz) radiation by an AlGaAs/GaAs HEMT up to third harmonic at room temperature and their resonant responses show very good agreement with the calculated results.

Hashim, A. M.; Alias, Q. I. [Faculty of Electrical Engineering, Universiti Teknologi Malaysia, 81310 Skudai, Johor (Malaysia); Kasai, S.; Hasegawa, H. [Research Center for Integrated Quantum Electronics, Hokkaido University North 12 West 8, Sapporo 060-8628 (Japan)

2010-03-11T23:59:59.000Z

70

Ultra-shallow quantum dots in an undoped GaAs/AlGaAs two-dimensional electron gas  

SciTech Connect

We report quantum dots fabricated on very shallow 2-dimensional electron gases, only 30 nm below the surface, in undoped GaAs/AlGaAs heterostructures grown by molecular beam epitaxy. Due to the absence of dopants, an improvement of more than one order of magnitude in mobility (at 2 Multiplication-Sign 10{sup 11} cm{sup -2}) with respect to doped heterostructures with similar depths is observed. These undoped wafers can easily be gated with surface metallic gates patterned by e-beam lithography, as demonstrated here from single-level transport through a quantum dot showing large charging energies (up to 1.75 meV) and excited state energies (up to 0.5 meV).

Mak, W. Y.; Sfigakis, F.; Beere, H. E.; Farrer, I.; Griffiths, J. P.; Jones, G. A. C.; Ritchie, D. A. [Cavendish Laboratory, University of Cambridge, Cambridge (United Kingdom)] [Cavendish Laboratory, University of Cambridge, Cambridge (United Kingdom); Das Gupta, K. [Cavendish Laboratory, University of Cambridge, Cambridge (United Kingdom) [Cavendish Laboratory, University of Cambridge, Cambridge (United Kingdom); Department of Physics, Indian Institute of Technology Bombay, Mumbai 400076 (India); Klochan, O.; Hamilton, A. R. [School of Physics, University of New South Wales, Sydney (Australia)] [School of Physics, University of New South Wales, Sydney (Australia)

2013-03-11T23:59:59.000Z

71

Temperature dependence and current transport mechanisms in Al{sub x}Ga{sub 1-x}N Schottky rectifiers  

SciTech Connect

GaN and Al{sub 0.25}Ga{sub 0.75}N lateral Schottky rectifiers were fabricated either with (GaN) or without (AlGaN) edge termination. The reverse breakdown voltage V{sub B} (3.1 kV for GaN; 4.3 kV for AlGaN) displayed a negative temperature coefficient of -6.0{+-}0.4 V K{sup -1} for both types of rectifiers. The reverse current originated from contact periphery leakage at moderate bias, while the forward turn-on voltage at a current density of 100 A cm-2 was {approx}5 V for GaN and {approx}7.5 V for AlGaN. The on-state resistances, R{sub ON}, were 50 m{omega} cm2 for GaN and 75 m{omega} cm2 for AlGaN, producing figures-of-merit (V{sub RB}){sup 2}/R{sub ON} of 192 and 246 MW cm-2, respectively. The activation energy of the reverse leakage was 0.13 eV at moderate bias. (c) 2000 American Institute of Physics.

Zhang, A. P. [Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611 (United States)] [Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611 (United States); Dang, G. [Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611 (United States)] [Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611 (United States); Ren, F. [Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611 (United States)] [Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611 (United States); Han, J. [Sandia National Laboratories, Albuquerque, New Mexico 87195 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87195 (United States); Polyakov, A. Y. [Institute of Rare Metals, Moscow 109017, Russia (Russian Federation)] [Institute of Rare Metals, Moscow 109017, Russia (Russian Federation); Smirnov, N. B. [Institute of Rare Metals, Moscow 109017, Russia (Russian Federation)] [Institute of Rare Metals, Moscow 109017, Russia (Russian Federation); Govorkov, A. V. [Institute of Rare Metals, Moscow 109017, Russia (Russian Federation)] [Institute of Rare Metals, Moscow 109017, Russia (Russian Federation); Redwing, J. M. [Epitronics, Phoenix, Arizona 85027 (United States)] [Epitronics, Phoenix, Arizona 85027 (United States); Cho, H. [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States)] [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Pearton, S. J. [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States)] [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States)

2000-06-19T23:59:59.000Z

72

Two-color picosecond experiments on anti-Stokes photoluminescence in GaAs/AlGaAs asymmetric double quantum wells  

E-Print Network (OSTI)

quantum wells S. C. Hohng and D. S. Kima) Department of Physics and Condensed Matter Research Institute in GaAs/AlGaAs asymmetric double quantum wells. Direct evidence for forbidden absorption is shown heterojunctions and asymmetric double quan- tum wells was found and its origin is still being hotly de- bated

Hohng, Sung Chul

73

Relaxation and critical strain for maximum In incorporation in AlInGaN on GaN grown by metal organic vapour phase epitaxy  

Science Conference Proceedings (OSTI)

Quaternary AlInGaN layers were grown on conventional GaN buffer layers on sapphire by metal organic vapour phase epitaxy at different surface temperatures and different reactor pressures with constant precursor flow conditions. A wide range in compositions within 30-62% Al, 5-29% In, and 23-53% Ga was covered, which leads to different strain states from high tensile to high compressive. From high-resolution x-ray diffraction and Rutherford backscattering spectrometry, we determined the compositions, strain states, and crystal quality of the AlInGaN layers. Atomic force microscopy measurements were performed to characterize the surface morphology. A critical strain value for maximum In incorporation near the AlInGaN/GaN interface is presented. For compressively strained layers, In incorporation is limited at the interface as residual strain cannot exceed an empirical critical value of about 1.1%. Relaxation occurs at about 15 nm thickness accompanied by strong In pulling. Tensile strained layers can be grown pseudomorphically up to 70 nm at a strain state of 0.96%. A model for relaxation in compressively strained AlInGaN with virtual discrete sub-layers, which illustrates the gradually changing lattice constant during stress reduction is presented.

Reuters, Benjamin; Finken, M.; Wille, A.; Kalisch, H.; Vescan, A. [RWTH Aachen University, GaN Device Technology, Sommerfeldstrasse 24, 52074 Aachen (Germany); Juelich Aachen Research Alliance, JARA-FIT, Wilhelm-Johnen-Strasse, 52428 Juelich (Germany); Hollaender, B. [Juelich Aachen Research Alliance, JARA-FIT, Wilhelm-Johnen-Strasse, 52428 Juelich (Germany); Forschungszentrum Juelich GmbH, PGI9-IT, 52425 Juelich (Germany); Heuken, M. [RWTH Aachen University, GaN Device Technology, Sommerfeldstrasse 24, 52074 Aachen (Germany); AIXTRON SE, Kaiserstr. 98, 52134 Herzogenrath (Germany)

2012-11-01T23:59:59.000Z

74

Method of extracting thermally stable optical signals from a GaAlAs LED source  

SciTech Connect

A self-compensating scheme is described that eliminates the need for temperature control devices employed in many LED-based optical test and measurement instruments to ensure optical signal stability. Thermal behavior of GaAlAs LED sources is exploited to provide an optical wavelength band signal with 0.1%/C power level stability.

Murtaza, G.; Senior, J.M. [Manchester Metropolitan Univ. (United Kingdom). Faculty of Science and Engineering

1995-05-01T23:59:59.000Z

75

US ESC TN Site Consumption  

Gasoline and Diesel Fuel Update (EIA)

60% 80% 100% US ESC TN OtherNone Propane Electricity Natural Gas MAIN HEATING FUEL USED COOLING EQUIPMENT USED DIVISION: East South Central (ESC) STATES INCLUDED: Alabama,...

76

Effect of Mg ionization efficiency on performance of Npn AlGaN/GaN heterojunction bipolar transistors  

SciTech Connect

A drift-diffusion transport model has been used to examine the performance capabilities of AlGaN/GaN Npn heterojunction bipolar transistors (HBTs). The Gummel plot from the first GaN-based HBT structure recently demonstrated is adjusted with simulation by using experimental mobility and lifetime reported in the literature. Numerical results have been explored to study the effect of the p-type Mg doping and its incomplete ionization in the base. The high base resistance induced by the deep acceptor level is found to be the cause of limiting current gain values. Increasing the operating temperature of the device activates more carriers in the base. An improvement of the simulated current gain by a factor of 2 to 4 between 25 and 300 C agrees well with the reported experimental results. A preliminary analysis of high frequency characteristics indicates substantial progress of predicted rf performances by operating the device at higher temperature due to a reduced extrinsic base resistivity.

MONIER,C.; PEARTON,S.J.; CHANG,PING-CHIH; BACA,ALBERT G.

2000-03-10T23:59:59.000Z

77

L7, Reduced Self-Heating in AlGaN/GaN HEMTs Using ...  

Science Conference Proceedings (OSTI)

Conference Tools for 2010 Electronic Materials Conference ... Electr. Dev., vol. 48, no. 3, pp. 465, 2001. [2] H. I. Fujishiro et al., Phys. Stat. Sol. (c) 2, no.

78

Pulsed atomic layer epitaxy of quaternary AlInGaN layers  

Science Conference Proceedings (OSTI)

In this letter, we report on a material deposition scheme for quaternary Al{sub x}In{sub y}Ga{sub 1-x--y}N layers using a pulsed atomic layer epitaxy (PALE) technique. The PALE approach allows accurate control of the quaternary layer composition and thickness by simply changing the number of aluminum, indium, and gallium pulses in a unit cell and the number of unit cell repeats. Using PALE, AlInGaN layers with Al mole fractions in excess of 40% and strong room-temperature photoluminescence peaks at 280 nm can easily be grown even at temperatures lower than 800{sup o}C. {copyright} 2001 American Institute of Physics.

Zhang, J.; Kuokstis, E.; Fareed, Q.; Wang, H.; Yang, J.; Simin, G.; Asif Khan, M.; Gaska, R.; Shur, M.

2001-08-13T23:59:59.000Z

79

US ESC TN Site Consumption  

U.S. Energy Information Administration (EIA) Indexed Site

ESC TN ESC TN Site Consumption million Btu $0 $500 $1,000 $1,500 $2,000 $2,500 US ESC TN Expenditures dollars ALL ENERGY average per household (excl. transportation) 0 4,000 8,000 12,000 16,000 US ESC TN Site Consumption kilowatthours $0 $400 $800 $1,200 $1,600 US ESC TN Expenditures dollars ELECTRICITY ONLY average per household * Tennessee households consume an average of 79 million Btu per year, about 12% less than the U.S. average. * Average electricity consumption for Tennessee households is 33% higher than the national average and among the highest in the nation, but spending for electricity is closer to average due to relatively low electricity prices. * Tennessee homes are typically newer, yet smaller in size, than homes in other parts of the country.

80

Electron and hole gas in modulation-doped GaAs/Al{sub 1-x}Ga{sub x}As radial heterojunctions  

Science Conference Proceedings (OSTI)

We perform self-consistent Schroedinger-Poisson calculations with exchange and correlation corrections to determine the electron and hole gas in a radial heterojunction formed in a GaAs/AlGaAs core-multi-shell nanowire, which is either n- or p-doped. We show that the electron and hole gases can be tuned to different localizations and symmetries inside the core as a function of the doping density/gate potential. Contrary to planar heterojunctions, conduction electrons do not form a uniform 2D electron gas (2DEG) localized at the GaAs/AlGaAs interface, but rather show a transition between an isotropic, cylindrical distribution deep in the GaAs core (low doping) and a set of six tunnel-coupled quasi-1D channels at the edges of the interface (high doping). Holes, on the other hand, are much more localized at the GaAs/AlGaAs interface. At low doping, they present an additional localization pattern with six separated 2DEGs strips. The field generated by a back-gate may easily deform the electron or hole gas, breaking the sixfold symmetry. Single 2DEGs at one interface or multiple quasi-1D channels are shown to form as a function of voltage intensity, polarity, and carrier type.

Bertoni, Andrea; Royo, Miquel; Mahawish, Farah; Goldoni, Guido [CNR-NANO S3, Istituto Nanoscienze, Via Campi 213/a, 41125 Modena (Italy); Department of Physics, University of Modena and Reggio Emilia and CNR-NANO S3, Istituto Nanoscienze, Via Campi 213/a, 41125 Modena (Italy)

2011-11-15T23:59:59.000Z

Note: This page contains sample records for the topic "tn al ga" from the National Library of EnergyBeta (NLEBeta).
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81

Gate-Recessed InAlN/GaN HEMTs on SiC Substrate With Al[subscript 2]O[subscript 3] Passivation  

E-Print Network (OSTI)

We studied submicrometer (L[subscript G] = 0.15-0.25 Ă Âżm) gate-recessed InAlN/AlN/GaN high-electron mobility transistors (HEMTs) on SiC substrates with 25-nm Al[subscript 2]O[subscript 3] passivation. The combination of ...

Guo, Shiping

82

Mid-infrared InAs/AlGaSb superlattice quantum-cascade lasers  

SciTech Connect

We report on the demonstration of mid-infrared InAs/AlGaSb superlattice quantum-cascade lasers operating at 10 {mu}m. The laser structures are grown on n-InAs (100) substrate by solid-source molecular-beam epitaxy. An InAs/AlGaSb chirped superlattice structure providing a large oscillator strength and fast carrier depopulation is employed as the active part. The observed minimum threshold current density at 80 K is 0.7 kA/cm{sup 2}, and the maximum operation temperature in pulse mode is 270 K. The waveguide loss of an InAs plasmon waveguide is estimated, and the factors that determine the operation temperature are discussed.

Ohtani, K.; Fujita, K.; Ohno, H. [Laboratory for Nanoelectronics and Semiconductor Spintronics, Research Institute of Electrical Communication, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai (Japan)

2005-11-21T23:59:59.000Z

83

Power Conversion Efficiency of AlGaAs/GaAs Schottky Diode for Low-Power On-Chip Rectenna Device Application  

Science Conference Proceedings (OSTI)

A Schottky diode has been designed and fabricated on n-AlGaAs/GaAs high-electron-mobility-transistor (HEMT) structure. Current-voltage (I-V) measurements show good device rectification with a Schottky barrier height of 0.4349 eV for Ni/Au metallization. The differences of Schottky barrier height from theoretical value are due to the fabrication process and smaller contact area. The RF signals up to 1 GHz are well rectified by the fabricated Schottky diodes and stable DC output voltage is obtained. Power conversion efficiency up to 50% is obtained at 1 GHz with series connection between diode and load. The fabricated the n-AlGaAs/GaAs Schottky diode provide conduit for breakthrough designs for ultra-low power on-chip rectenna device technology to be integrated in nanosystems.

Mustafa, Farahiyah; Hashim, Abdul Manaf; Rahman, Shaharin Fadzli Abd [Material Innovations and Nanoelectronics Research Group, Faculty of Electrical Engineering, Universiti Teknologi Malaysia, 81310 Skudai (Malaysia); Ibnu Sina Institute for Fundamental Science Studies, Universiti Teknologi Malaysia, 81310 Skudai Johor Malaysia (Malaysia); Osman, Mohd Nizam [Telekom Research and Development, TM Innovation Centre, 63000 Cyberjaya (Malaysia)

2011-05-25T23:59:59.000Z

84

Transmission electron microscopy characterization of electrically stressed AlGaN/GaN high electron mobility transistor devices  

Science Conference Proceedings (OSTI)

A set of AlGaN/GaN high electron mobility transistor devices has been investigated using step-stress testing, and representative samples of undegraded, source-side-degraded, and drain-side-degraded devices were examined using electron microscopy and microanalysis. An unstressed reference sample was also examined. All tested devices and their corresponding transmission electron microscopy samples originated from the same wafer and thus received nominally identical processing. Step-stressing was performed on each device and the corresponding current voltage characteristics were generated. Degradation in electrical performance, specifically greatly increased gate leakage current, was shown to be correlated with the presence of crystal defects near the gate edges. However, the drain-side-degraded device showed a surface pit on the source side, and another region of the same device showed no evidence of damage. Moreover, significant metal diffusion into the barrier layer from the gate contacts was also observed, as well as thin amorphous oxide layers below the gate metal contacts, even in the unstressed sample. Overall, these observations emphasize that gate-edge defects provide only a partial explanation for device failure.

Johnson, Michael [Arizona State University; Cullen, David A [ORNL; Liu, Lu [University of Florida; Kang, Tsung Sheng [University of Florida, Gainesville; Ren, F. [University of Florida; Chang, C. Y. [University of Florida; Pearton, S. J. [University of Florida; Jang, Soohwan [University of Florida, Gainesville; Johnson, Wayne J. [Kopin Corporation, Taunton, MA; Smith, David J [Arizona State University

2012-01-01T23:59:59.000Z

85

Final report on LDRD project : outstanding challenges for AlGaInN MOCVD.  

Science Conference Proceedings (OSTI)

The AlGaInN material system is used for virtually all advanced solid state lighting and short wavelength optoelectronic devices. Although metal-organic chemical vapor deposition (MOCVD) has proven to be the workhorse deposition technique, several outstanding scientific and technical challenges remain, which hinder progress and keep RD&A costs high. The three most significant MOCVD challenges are: (1) Accurate temperature measurement; (2) Reliable and reproducible p-doping (Mg); and (3) Low dislocation density GaN material. To address challenge (1) we designed and tested (on reactor mockup) a multiwafer, dual wavelength, emissivity-correcting pyrometer (ECP) for AlGaInN MOCVD. This system simultaneously measures the reflectance (at 405 and 550 nm) and emissivity-corrected temperature for each individual wafer, with the platen signal entirely rejected. To address challenge (2) we measured the MgCp{sub 2} + NH{sub 3} adduct condensation phase diagram from 65-115 C, at typical MOCVD concentrations. Results indicate that it requires temperatures of 80-100 C in order to prevent MgCp{sub 2} + NH{sub 3} adduct condensation. Modification and testing of our research reactor will not be complete until FY2005. A new commercial Veeco reactor was installed in early FY2004, and after qualification growth experiments were conducted to improve the GaN quality using a delayed recovery technique, which addresses challenge (3). Using a delayed recovery technique, the dislocation densities determined from x-ray diffraction were reduced from 2 x 10{sup 9} cm{sup -2} to 4 x 10{sup 8} cm{sup -2}. We have also developed a model to simulate reflectance waveforms for GaN growth on sapphire.

Mitchell, Christine Charlotte; Follstaedt, David Martin; Russell, Michael J.; Cross, Karen Charlene; Wang, George T.; Creighton, James Randall; Allerman, Andrew Alan; Koleske, Daniel David; Lee, Stephen Roger; Coltrin, Michael Elliott

2005-03-01T23:59:59.000Z

86

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

87

Thermal stability of the deep ultraviolet emission from AlGaN/AlN Stranski-Krastanov quantum dots  

Science Conference Proceedings (OSTI)

We report on the structural and optical properties of AlGaN/AlN quantum dot (QD) superlattices synthesized by plasma-assisted molecular-beam epitaxy. Modifying the composition and geometry of the QDs, the peak emission wavelength can be shifted from 320 nm to 235 nm while keeping the internal quantum efficiency larger than 30%. The efficient carrier confinement is confirmed by the stability of the photoluminescence (PL) intensity and decay time, from low temperature up to 100 K. Above this threshold, the PL intensity decreases and the radiative lifetime increases due to carrier thermalization. We also identified the intraband electronic transition between the ground level of the conduction band and the first excited state confined along the growth axis (s-p{sub z}).

Himwas, C.; Songmuang, R.; Le Si Dang [CEA-CNRS Group 'Nanophysique et Semiconducteurs,' Institut Neel-CNRS, 25 rue des Martyrs, 38042 Grenoble Cedex 9 (France); Bleuse, J.; Monroy, E. [CEA-CNRS Group 'Nanophysique et Semiconducteurs,' INAC-SP2M, CEA-Grenoble, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France); Rapenne, L.; Sarigiannidou, E. [INP-Grenoble/Minatec, 3 parvis Louis Neel BP257, 38016 Grenoble (France)

2012-12-10T23:59:59.000Z

88

Time-resolved resonance and linewidth of an ultrafast switched GaAs/AlAs microcavity  

E-Print Network (OSTI)

We explore a planar GaAs/AlAs photonic microcavity using pump-probe spectroscopy. Free carriers are excited in the GaAs with short pump pulses. The time-resolved reflectivity is spectrally resolved short probe pulses. We show experimentally that the cavity resonance and its width depend on the dynamic refractive index of both the lambda-slab and the lambda/4 GaAs mirrors. We clearly observe a double exponential relaxation of both the the cavity resonance and its width, which is due to the different recombination timescales in the lambda-slab and the mirrors. In particular, the relaxation time due to the GaAs mirrors approaches the photon storage time of the cavity, a regime for which nonlinear effects have been predicted. The strongly non-single exponential behavior of the resonance and the width is in excellent agreement to a transfer-matrix model taking into account two recombination times. The change in width leads to a change in reflectivity modulation depth. The model predicts an optimal cavity Q for any...

Harding, Philip J; Hartsuiker, Alex; Nowicki-Bringuier, Yoanna-Reine; Gerard, Jean-Michel; Vos, Willem L

2009-01-01T23:59:59.000Z

89

Atomic-layer-deposited Al2O3 and HfO2 on GaN: A comparative study on interfaces and electrical characteristics  

Science Conference Proceedings (OSTI)

Al"2O"3, HfO"2, and composite HfO"2/Al"2O"3 films were deposited on n-type GaN using atomic layer deposition (ALD). The interfacial layer of GaON and HfON was observed between HfO"2 and GaN, whereas the absence of an interfacial layer at Al"2O"3/GaN ... Keywords: Al2O3, Atomic-layer-deposition (ALD), GaN, HfO2, High k dielectric, MOS

Y. C. Chang; M. L. Huang; Y. H. Chang; Y. J. Lee; H. C. Chiu; J. Kwo; M. Hong

2011-07-01T23:59:59.000Z

90

Scattering and electron mobility in combination-doped HFET-structures AlGaAs/InGaAs/AlGaAs with high electron density  

Science Conference Proceedings (OSTI)

Molecular-beam epitaxy is used for growing structures differing in doping technique and doping level and having a high two-dimensional-electron concentration n{sub s} in the quantum well. The effect of doping combining uniform and {delta} doping on the electron-transport properties of heterostructures is investigated. A new type of structure with a two-sided silicon {delta} doping of GaAs transition layers located on the quantum-well boundaries is proposed. The largest value of electron mobility {mu}{sub H} = 1520 cm{sup 2}/(V s) is obtained simultaneously with a high electron density n{sub s} = 1.37 Multiplication-Sign 10{sup 13} cm{sup -2} at 300 K with such a doping. It is associated with decreasing electron scattering by an ionized impurity, which is confirmed by the carried out calculations.

Khabibullin, R. A., E-mail: khabibullin_r@mail.ru; Vasil'evskii, I. S. [MEPHI National Research Nuclear University (Russian Federation); Galiev, G. B.; Klimov, E. A. [Russian Academy of Sciences, Institute of Ultrahigh-Frequency Semiconductor Electronics (Russian Federation); Ponomarev, D. S. [MEPHI National Research Nuclear University (Russian Federation); Lunin, R. A.; Kulbachinskii, V. A. [Moscow State University (Russian Federation)

2011-10-15T23:59:59.000Z

91

Category:Memphis, TN | Open Energy Information  

Open Energy Info (EERE)

Memphis, TN Memphis, TN Jump to: navigation, search Go Back to PV Economics By Location Media in category "Memphis, TN" The following 16 files are in this category, out of 16 total. SVFullServiceRestaurant Memphis TN City of Memphis Tennessee (Utility Company).png SVFullServiceRestauran... 66 KB SVHospital Memphis TN City of Memphis Tennessee (Utility Company).png SVHospital Memphis TN ... 69 KB SVLargeHotel Memphis TN City of Memphis Tennessee (Utility Company).png SVLargeHotel Memphis T... 67 KB SVLargeOffice Memphis TN City of Memphis Tennessee (Utility Company).png SVLargeOffice Memphis ... 70 KB SVMediumOffice Memphis TN City of Memphis Tennessee (Utility Company).png SVMediumOffice Memphis... 65 KB SVMidriseApartment Memphis TN City of Memphis Tennessee (Utility Company).png

92

Polarization-balanced design of AlN/GaN heterostructures: Application to double-barrier structures  

E-Print Network (OSTI)

Inversion- and depletion- regions generally form at the interfaces between doped leads (cladding layers) and the active region in wurtzite c-plane AlN/GaN heterostructures. The band bending in the depletion region can seriously impede perpendicular electronic transport. To counter the formation of these regions, we consider polarization-balanced designs of AlN/GaN heterostructures based on matching the applied bias to the internal voltage drop arising from spontaneous and piezeolectric fields. To retain freedom of design we use alloyed Al$_{\\tilde{x}}$Ga$_{1-\\tilde{x}}$N leads. Use of pure GaN leads requires huge voltage drops which severely restricts design. The alloy concentration $\\tilde{x}$ tunes the internal voltage drop over the structure. For short active regions comprised of AlN and GaN layers, we derive a simple relation between the applied bias, average alloy composition of the active region, and the alloy concentration of the leads. We study polarization-balanced designs for AlN barriers structures...

Berland, Kristian; Hyldgaard, Per

2011-01-01T23:59:59.000Z

93

Category:Nashville, TN | Open Energy Information  

Open Energy Info (EERE)

Nashville, TN Nashville, TN Jump to: navigation, search Go Back to PV Economics By Location Media in category "Nashville, TN" The following 16 files are in this category, out of 16 total. SVFullServiceRestaurant Nashville TN City of Memphis Tennessee (Utility Company).png SVFullServiceRestauran... 67 KB SVHospital Nashville TN City of Memphis Tennessee (Utility Company).png SVHospital Nashville T... 71 KB SVLargeHotel Nashville TN City of Memphis Tennessee (Utility Company).png SVLargeHotel Nashville... 68 KB SVLargeOffice Nashville TN City of Memphis Tennessee (Utility Company).png SVLargeOffice Nashvill... 71 KB SVMediumOffice Nashville TN City of Memphis Tennessee (Utility Company).png SVMediumOffice Nashvil... 67 KB SVMidriseApartment Nashville TN City of Memphis Tennessee (Utility Company).png

94

Theoretical And Experimental Studies Of The Effects Of Rapid Thermal Annealing In GaAs/AlGaAs Quantum Dots Grown By Droplet Epitaxy  

Science Conference Proceedings (OSTI)

We fabricated low-density GaAs/AlGaAs quantum dots for single photon source by droplet epitaxy. We investigated the emission energies of the dots and underlying superlattice by using photoluminescence and cathodoluminescence measurements. By forming a mesa etched structure, we distinguished the transitions from the superlattice and the dots. And we calculated the diffusion length in this system from the peak shift of the superlattice, and applied the diffusion to the dots to investigate the emission energy shift of the QDs.z

Moon, P. [Nano Convergence Devices Center, Korea Institute of Science and Technology, Seoul (Korea, Republic of); School of Materials Science, Japan Advanced Institute of Science and Technology, Ishikawa (Japan); Ha, S.-K.; Song, J. D.; Lim, J. Y.; Choi, W. J.; Han, I. K.; Lee, J. I. [Nano Convergence Devices Center, Korea Institute of Science and Technology, Seoul (Korea, Republic of); Bounouar, S.; Donatini, F.; Dang, L. S.; Poizat, J. P. [CEA/CNRS/UJF team 'Nanophysics and semiconductors', Institute Neel/CNRS-UJF, Grenoble (France); Kim, J. S. [Department of Physics, Yeungnam University, Gyeonsan (Korea, Republic of)

2011-12-23T23:59:59.000Z

95

Single photon emission from impurity centers in AlGaAs epilayers on Ge and Si substrates  

SciTech Connect

We show that the epitaxial growth of thin layers of AlGaAs on Ge and Si substrates allows to obtain single photon sources by exploiting the sparse and unintentional contamination with acceptors of the AlGaAs. Very bright and sharp single photoluminescence lines are observed in confocal microscopy. These lines behave very much as single excitons in quantum dots, but their implementation is by far much easier, since it does not require 3D nucleation. The photon antibunching is demonstrated by time resolved Hanbury Brown and Twiss measurements.

Minari, S.; Cavigli, L.; Sarti, F.; Abbarchi, M.; Accanto, N.; Munoz Matutano, G.; Vinattieri, A.; Gurioli, M. [Dipartimento di Fisica e Astronomia, LENS and CNISM, Universita di Firenze, Via Sansone 1, I-50019 Firenze (Italy); Bietti, S.; Sanguinetti, S. [Dipartimento di Scienza dei Materiali and L-NESS, Universita di Milano Bicocca, Via Cozzi 53, I-20125 Milano (Italy)

2012-10-22T23:59:59.000Z

96

II3, 2?m Thick Device Quality GaN on Si(111) Using AlGaN Graded ...  

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 ...

97

Effect of antimony nano-scale surface-structures on a GaSb/AlAsSb distributed Bragg reflector  

SciTech Connect

Effects of antimony crystallization on the surface of GaSb during low temperature molecular beam epitaxy growth are investigated. The geometry of these structures is studied via transmission electron and atomic force microscopies, which show the surface metal forms triangular-shaped, elongated nano-wires with a structured orientation composed entirely of crystalline antimony. By depositing antimony on a GaSb/AlAsSb distributed Bragg reflector, the field is localized within the antimony layer. Polarization dependent transmission measurements are carried out on these nano-structures deposited on a GaSb/AlAsSb distributed Bragg reflector. It is shown that the antimony-based structures at the surface favor transmission of light polarized perpendicular to the wires.

Husaini, S.; Shima, D.; Ahirwar, P.; Rotter, T. J.; Hains, C. P.; Dang, T.; Bedford, R. G.; Balakrishnan, G. [Air Force Research Laboratory, Sensors Directorate, Wright-Patterson AFB, Dayton, OH 45433 (United States)] [Air Force Research Laboratory, Sensors Directorate, Wright-Patterson AFB, Dayton, OH 45433 (United States)

2013-02-11T23:59:59.000Z

98

NJ WY AK AL CA AR CO CT DE FL GA HI ID KS IL IN IA IA KY LA  

Gasoline and Diesel Fuel Update (EIA)

176, "Annual Report of Natural and Supplemental Gas Supply and Disposition." NJ WY AK AL CA AR CO CT DE FL GA HI ID KS IL IN IA IA KY LA ME MI MA MD MN MS MT MO NE ND OH NV NM NY...

99

Sub-250 nm room-temperature optical gain from AlGaN/AlN multiple quantum wells with strong band-structure potential fluctuations  

Science Conference Proceedings (OSTI)

Deep-UV optical gain has been demonstrated in Al{sub 0.7}Ga{sub 0.3}N/AlN multiple quantum wells under femtosecond optical pumping. Samples were grown by molecular beam epitaxy under a growth mode that introduces band structure potential fluctuations and high-density nanocluster-like features within the AlGaN wells. A maximum net modal gain value of 118 {+-} 9 cm{sup -1} has been measured and the transparency threshold of 5 {+-} 1 {mu}J/cm{sup 2} was experimentally determined, corresponding to 1.4 x 10{sup 17} cm{sup -3} excited carriers. These findings pave the way for the demonstration of solid-state lasers with sub-250 nm emission at room temperature.

Francesco Pecora, Emanuele; Zhang Wei; Nikiforov, A.Yu.; Yin Jian; Paiella, Roberto; Dal Negro, Luca; Moustakas, T. D. [Department of Electrical and Computer Engineering and Photonics Center, Boston University, 8 Saint Mary's Street, Boston, Massachusetts 02215 (United States); Zhou Lin; Smith, David J. [Department of Physics, Arizona State University, Tempe, Arizona 85287 (United States)

2012-02-06T23:59:59.000Z

100

Effect of AlN buffer layer properties on the morphology and polarity of GaN nanowires grown by molecular beam epitaxy  

SciTech Connect

Low-temperature AlN buffer layers grown via plasma-assisted molecular beam epitaxy on Si (111) were found to significantly affect the subsequent growth morphology of GaN nanowires. The AlN buffer layers exhibited nanowire-like columnar protrusions, with their size, shape, and tilt determined by the AlN V/III flux ratio. GaN nanowires were frequently observed to adopt the structural characteristics of the underlying AlN columns, including the size and the degree of tilt. Piezoresponse force microscopy and polarity-sensitive etching indicate that the AlN films and the protruding columns have a mixed crystallographic polarity. Convergent beam electron diffraction indicates that GaN nanowires are Ga-polar, suggesting that Al-polar columns are nanowire nucleation sites for Ga-polar nanowires. GaN nanowires of low density could be grown on AlN buffers that were predominantly N-polar with isolated Al-polar columns, indicating a high growth rate for Ga-polar nanowires and suppressed growth of N-polar nanowires under typical growth conditions. AlN buffer layers grown under slightly N-rich conditions (V/III flux ratio = 1.0 to 1.3) were found to provide a favorable growth surface for low-density, coalescence-free nanowires.

Brubaker, Matt D. [Physical Measurement Laboratory, National Institute of Standards and Technology, Boulder, Colorado 80305 (United States); Department of Mechanical Engineering, University of Colorado, Boulder, Colorado 80309 (United States); DARPA Center for Integrated Micro/Nano-Electromechanical Transducers (iMINT), University of Colorado, Boulder, Colorado 80309 (United States); Levin, Igor; Davydov, Albert V. [Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Rourke, Devin M.; Sanford, Norman A.; Bertness, Kris A. [Physical Measurement Laboratory, National Institute of Standards and Technology, Boulder, Colorado 80305 (United States); Bright, Victor M. [Department of Mechanical Engineering, University of Colorado, Boulder, Colorado 80309 (United States); DARPA Center for Integrated Micro/Nano-Electromechanical Transducers (iMINT), University of Colorado, Boulder, Colorado 80309 (United States)

2011-09-01T23:59:59.000Z

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


101

Activation energy of degradation in GaAlAs double heterostructure laser diodes  

SciTech Connect

Aging test of GaAlAs double heterostructure (DH) laser diodes is performed in the temperature range of 50--180 /sup 0/C. In samples for the aging test, AuSn-alloy bonding solder is used and the facet coating with Al/sub 2/O/sub 3/ film is performed. Samples are operated in the light emitting diode (LED) mode with the application of the constant current of 4 kA/cm/sup 2/ and 6 kA/cm/sup 2/ at temperatures above 80 /sup 0/C and in the automatic power control (APC) lasing mode with the constant optical power of 5 mW/facet at 50 and 70 /sup 0/C. The activation energy is 0.5 eV obtained from the results of the LED mode operation at 4 kA/cm/sup 2/. The parameter to evaluate the degradation is the current at which the optical power at 25 /sup 0/C is 5 mW/facet. This parameter includes the deterioration of the external differencial efficiency. It is shown that the increasing rates of this parameter are almost the same at the same temperature between the LED mode operation at 4 kA/cm/sup 2/ and 6 kA/cm/sup 2/. The increasing rate is almost the same when samples are operated in the APC lasing mode. Twenty-three samples operated at 70 /sup 0/C maintain the optical power of 5 mW/facet set initially over 5000 h. The averaged increasing rate of that parameter in these samples is 7.1 x 10/sup -6//h. The activation energy of 0.5 eV is almost the same as that of GaAlAs DH LED's which is 0.56 eV. It is presumed that point defects which disperse homogeneously cause the degradation of laser diodes and this degradation mode seemed to be the same as LED owing to the improvements against the facet degradation and the contact degradation.

Imai, H.; Hori, K.; Takusagawa, M.; Wakita, K.

1981-05-01T23:59:59.000Z

102

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

103

Improvement of near-infrared absorption linewidth in AlGaN/GaN superlattices by optimization of delta-doping location  

Science Conference Proceedings (OSTI)

We report a systematic study of the near-infrared intersubband absorption in AlGaN/GaN superlattices grown by plasma-assisted molecular-beam epitaxy as a function of Si-doping profile with and without {delta}-doping. The transition energies are in agreement with theoretical calculations including many-body effects. A dramatic reduction of the intersubband absorption linewidth is observed when the {delta}-doping is placed at the end of the quantum well. This reduction is attributed to the improvement of interface roughness. The linewidth dependence on interface roughness is well reproduced by a model that considers the distribution of well widths measured with transmission electron microscopy.

Edmunds, C.; Cervantes, M.; Malis, O. [Department of Physics, Purdue University, West Lafayette, Indiana 47907 (United States); Tang, L.; Shao, J.; Li, D. [Department of Physics, Purdue University, West Lafayette, Indiana 47907 (United States); Birck Nanotechnology Center, West Lafayette, Indiana 47907 (United States); Gardner, G. [Birck Nanotechnology Center, West Lafayette, Indiana 47907 (United States); School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Zakharov, D. N. [Birck Nanotechnology Center, West Lafayette, Indiana 47907 (United States); Manfra, M. J. [Department of Physics, Purdue University, West Lafayette, Indiana 47907 (United States); Birck Nanotechnology Center, West Lafayette, Indiana 47907 (United States); School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907 (United States)

2012-09-03T23:59:59.000Z

104

Improved Off-State Stress Critical Voltage on AlGaN/GaN High Electron Mobility Transistors Utilizing Pt/Ti/Au Based Gate Metallization  

Science Conference Proceedings (OSTI)

The critical voltage for degradation of AlGaN/GaN high electron mobility transistors (HEMTs) employed with the Pt/Ti/Au gate metallization instead of the commonly used Ni/Au was significantly increased during the off-state stress. The typical critical voltage for HEMTs with Ni/Au gate metallization was around -60V. By sharp contrast, no critical voltage was observed for the HEMTs with Pt/Ti/Au gate metallization, even up to -100V, which was the instrumental limitation in this experiment. Both Schottky forward and reverse gate characteristics of the Ni/Au degraded once the gate voltage passed the critical voltage of around -60V. There was no degradation exhibited for the HEMTs with Pt-gated HEMTs.

Lo, C. F. [University of Florida; Liu, L. [University of Florida, Gainesville; Kang, Tsung Sheng [University of Florida, Gainesville; Davies, Ryan [University of Florida; Gila, Brent P. [University of Florida, Gainesville; Pearton, S. J. [University of Florida; Kravchenko, Ivan I [ORNL; Laboutin, O. [Kopin Corporation, Taunton, MA; Cao, Yu [Kopin Corporation, Taunton, MA; Johnson, Wayne J. [Kopin Corporation, Taunton, MA; Ren, F. [University of Florida

2011-01-01T23:59:59.000Z

105

Real-time x-ray response of biocompatible solution gate AlGaN/GaN high electron mobility transistor devices  

Science Conference Proceedings (OSTI)

We present the real-time x-ray irradiation response of charge and pH sensitive solution gate AlGaN/GaN high electron mobility transistors. The devices show stable and reproducible behavior under and following x-ray radiation, including a linear integrated response with dose into the muGy range. Titration measurements of devices in solution reveal that the linear pH response and sensitivity are not only retained under x-ray irradiation, but an irradiation response could also be measured. Since the devices are biocompatible, and can be simultaneously operated in aggressive fluids and under hard radiation, they are well-suited for both medical radiation dosimetry and biosensing applications.

Hofstetter, Markus; Funk, Maren; Paretzke, Herwig G.; Thalhammer, Stefan [Helmholtz Zentrum Muenchen, Ingolstaedter Landstrasse 1, 85764 Neuherberg (Germany); Howgate, John; Sharp, Ian D.; Stutzmann, Martin [Walter Schottky Institut, Technische Universitaet Muenchen, Am Coulombwall 3, 85748 Garching (Germany)

2010-03-01T23:59:59.000Z

106

Murdock Road Knoxville.TN  

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

702 702 Murdock Road Knoxville.TN 37932 Tel: (609) 921-1456 Fax: (609) 92 1-8703 AA\W.nell-one.com March 25,2009 Office of the Assistant General Counsel for Technology Transfer and Intellectual Property U.S. Department of Energy 1000 Independence Avenue, SW Washington, DC 20585 Attn: Technology Transfer Questions Subject: Questions Concerning Technology Transfer Practices at DOE Laboratories (Federal RegisterNol. 73, No. 229/ November 26,2008 /Notices) Dear Mr. Gottlieb, Thank you for the opportunity to respond to the questions published in the Federal Register. As Chief Executive Officer of Nell One Therapeutics, a spin-out company which is in the process of licensing technology from Oak Ridge National Laboratory (ORNL), I found the questions to be highly relevant to our experiences. While many great technologies and capabilities reside in the National Laboratories

107

High photo-excited carrier multiplication by charged InAs dots in AlAs/GaAs/AlAs resonant tunneling diode  

E-Print Network (OSTI)

We present an approach for the highly sensitive photon detection based on the quantum dots (QDs) operating at temperature of 77K. The detection structure is based on an AlAs/GaAs/AlAs double barrier resonant tunneling diode combined with a layer of self-assembled InAs QDs (QD-RTD). A photon rate of 115 photons per second had induced 10nA photocurrent in this structure, corresponding to the photo-excited carrier multiplication factor of 10^7. This high multiplication factor is achieved by the quantum dot induced memory effect and the resonant tunneling tuning effect of QD-RTD structure.

Wang, Wangping; Xiong, Dayuan; Li, Ning; Lu, Wei

2007-01-01T23:59:59.000Z

108

High photo-excited carrier multiplication by charged InAs dots in AlAs/GaAs/AlAs resonant tunneling diode  

E-Print Network (OSTI)

We present an approach for the highly sensitive photon detection based on the quantum dots (QDs) operating at temperature of 77K. The detection structure is based on an AlAs/GaAs/AlAs double barrier resonant tunneling diode combined with a layer of self-assembled InAs QDs (QD-RTD). A photon rate of 115 photons per second had induced 10nA photocurrent in this structure, corresponding to the photo-excited carrier multiplication factor of 10^7. This high multiplication factor is achieved by the quantum dot induced memory effect and the resonant tunneling tuning effect of QD-RTD structure.

Wangping Wang; Ying Hou; Dayuan Xiong; Ning Li; Wei Lu

2007-10-15T23:59:59.000Z

109

Drift velocity of electrons in quantum wells of selectively doped In{sub 0.5}Ga{sub 0.5}As/Al{sub x}In{sub 1-x}As and In{sub 0.2}Ga{sub 0.8}As/Al{sub x}Ga{sub 1-x}As heterostructures in high electric fields  

Science Conference Proceedings (OSTI)

The field dependence of drift velocity of electrons in quantum wells of selectively doped In{sub 0.5}Ga{sub 0.5}As/Al{sub x}In{sub 1-x}As and In{sub 0.2}Ga{sub 0.8}As/Al{sub x}Ga{sub 1-x}As heterostructures is calculated by the Monte Carlo method. The influence of varying the molar fraction of Al in the composition of the Al{sub x}Ga{sub 1-x}As and Al{sub x}In{sub 1-x}As barriers of the quantum well on the mobility and drift velocity of electrons in high electric fields is studied. It is shown that the electron mobility rises as the fraction x of Al in the barrier composition is decreased. The maximum mobility in the In{sub 0.5}Ga{sub 0.5}As/In{sub 0.8}Al{sub 0.2}As quantum wells exceeds the mobility in a bulk material by a factor of 3. An increase in fraction x of Al in the barrier leads to an increase in the threshold field E{sub th} of intervalley transfer (the Gunn effect). The threshold field is E{sub th} = 16 kV/cm in the In{sub 0.5}Ga{sub 0.5}As/Al{sub 0.5}In{sub 0.5}As heterostructures and E{sub th} = 10 kV/cm in the In{sub 0.2}Ga{sub 0.8}As/Al{sub 0.3}Ga{sub 0.7}As heterostructures. In the heterostructures with the lowest electron mobility, E{sub th} = 2-3 kV/cm, which is lower than E{sub th} = 4 kV/cm in bulk InGaAs.

Pozela, J., E-mail: pozela@pfi.lt; Pozela, K.; Raguotis, R.; Juciene, V. [Center for Physical Sciences and Technology, Semiconductor Physics Institute (Lithuania)

2011-06-15T23:59:59.000Z

110

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

111

Strain control of AlGaN/GaN high electron mobility transistor structures on silicon (111) by plasma assisted molecular beam epitaxy  

Science Conference Proceedings (OSTI)

This paper reports on the use of plasma assisted molecular beam epitaxy of AlGaN/GaN-based high electron mobility transistor structures grown on 4 in. Si (111) substrates. In situ measurements of wafer curvature during growth proved to be a very powerful method to analyze the buffer layer's thickness dependent strain. The Ga/N ratio at the beginning of growth of the GaN buffer layer is the critical parameter to control the compressive strain of the entire grown structure. An engineered amount of compressive strain must be designed into the structure to perfectly compensate for the tensile strain caused by differences in the thermal expansion coefficient between the epi-layer and substrate during sample cool down from growth temperatures. A maximum film thickness of 4.2 {mu}m was achieved without the formation of any cracks and a negligible bow of the wafers below 10 {mu}m. Measurement of the as-grown wafers revealed depth profiles of the charge carrier concentration comparable to values achieved on SiC substrates and mobility values of the two dimensional electron gas in the range 1230 to 1350 cm{sup 2}/Vs at a charge carrier concentration of 6.5-7 10{sup 12}/cm{sup 2}. First results on processed wafers with 2 {mu}m thick buffer layer indicate very promising results with a resistance of the buffer, measured on 200 {mu}m long contacts with 15 {mu}m pitch, in the range of R > 10{sup 9}{Omega} at 100 V and breakdown voltages up to 550 V.

Aidam, Rolf; Diwo, Elke; Rollbuehler, Nicola; Kirste, Lutz; Benkhelifa, Fouad [Fraunhofer-Institute for Applied Solid State Physics, Tullastrasse 72, 79108 Freiburg (Germany)

2012-06-01T23:59:59.000Z

112

Growth and properties of InGaAs/FeAl/InAlAs/InP heterostructures for buried reflector/interconnect applications in InGaAs thermophotovoltaic devices  

DOE Green Energy (OSTI)

Thermophotovoltaic cells consisting of InGaAs active layers are of extreme promise for high efficiency, low bandgap TPV conversion. In the monolithic interconnected module configuration, the presence of the InGaAs lateral conduction layer (LCL) necessary for the series connection between TPV cells results in undesirable free carrier absorption, causing a tradeoff between series resistance and optical absorption losses in the infrared. A potential alternative is to replace the LCL with an epitaxial metal layer that would provide a low-resistance interconnect while not suffering from free carrier absorption. The internal metal layer would also serve as an efficient, panchromatic back surface reflector, providing the additional advantage of increased effective optical thickness of the InGaAs cell. In this paper, the authors present the first results on the growth and development of buried epitaxial metal layers for TPV applications. High quality, single crystal, epitaxial Fe{sub x}Al{sub 1{minus}x} layers were grown on InAlAs/InP substrates, having compositions in the range x = 0.40--0.80. Epitaxial metal layers up to 1,000 {angstrom} in thickness were achieved, with excellent uniformity over large areas and atomically smooth surfaces. X-ray diffraction studies indicate that all FeAl layers are strained with respect to the substrate, for the entire composition range studied and for all thicknesses. The FeAl layers exhibit excellent resistance characteristics, with resistivities from 60 {micro}ohm-cm to 100 {micro}ohm-cm, indicating that interface scattering has a negligible effect on lateral conductivity. Reflectance measurements show that the FeAl thickness must be at least 1,000 {angstrom} to achieve > 90% reflection in the infrared.

Ringel, S.A.; Sacks, R.N.; Qin, L. [Ohio State Univ., Columbus, OH (United States). Dept. of Electrical Engineering; Clevenger, M.B.; Murray, C.S. [Bettis Atomic Power Lab., West Mifflin, PA (United States)

1998-11-01T23:59:59.000Z

113

Spin injection into semiconductors : the role of Fe/Al[sub x]Ga[sub 1-x]As interface  

SciTech Connect

The influence of the growth and post-growth annealing temperatures of Fe/Al{sub x}Ga{sub 1-x}As-based spin light-emitting diodes (LEDs) on the spin injection efficiency is discussed. The extent of interfacial reactions during molecular beam epitaxial growth of Fe on GaAs was determined from in-situ x-ray photoelectron spectroscopy studies. The Fe/GaAs interface results in {<=} 3 monolayers of reaction for Fe grown at -15 C. Intermediate growth temperatures (95 C) lead to {approx}5 monolayers of interfacial reactions, and high growth temperatures of 175 C lead to a {approx}9 monolayer thick reacted layer. Polarized neutron reflectivity was used to determine the interfacial magnetic properties of epitaxial Fe{sub 0.5}Co{sub 0.5}/GaAs heterostructures grown under identical conditions. No interfacial magnetic dead layer is detected at the interface for Fe{sub 0.5}Co{sub 0.5} films grown at -15 C, an {approx}6 {angstrom} thick nonmagnetic layer formed at the interface for 95 C growth and an {approx}5 {angstrom} thick magnetic interfacial reacted layer formed for growth at 175 C. Spin injection from Fe contacts into spin LEDs decreases sharply when reactions result in a nonmagnetic interfacial layer. Significant spin injection signals are obtained from Fe contacts grown between -5 C and 175 C, although the higher Fe growth temperatures resulted in a change in the sign of the spin polarization. Post-growth annealing of the spin LEDs is found to increase spin injection efficiency for low Fe growth temperatures and to a sign reversal of the spin polarization for high growth temperature (175 C). An effective Schottky barrier height increase indicates that post growth annealing modifies the Fe/Al{sub x}Ga{sub 1-x}As interface.

Fitzsimmons, M. R. (Michael R.); Park, S. (Sungkyun)

2004-01-01T23:59:59.000Z

114

Evolution of AlN buffer layers on Silicon and the effect on the property of the expitaxial GaN film  

E-Print Network (OSTI)

The morphology evolution of high-temperature grown AlN nucleation layers on (111) silicon has been studied using atomic force microscopy (AFM). The structure and morphology of subsequently grown GaN film were characterized ...

Zang, Keyan

115

II2, GaN/AlN Heterostructures on Vertical {111} Fin Facets of Si (110)  

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 ...

116

Comparison of dc performance of Pt/Ti/Au- and Ni/Au-Gated AlGaN/GaN High Electron Mobility Transistors  

Science Conference Proceedings (OSTI)

We have demonstrated significant improvements of AlGaN/GaN High Electron Mobility Transistors (HEMTs) dc performance by employing Pt/Ti/Au instead of the conventional Ni/Au gate metallization. During off-state bias stressing, the typical critical voltage for HEMTs with Ni/Au gate metallization was ~ -45 to -65V. By sharp contrast, no critical voltage was observed for HEMTs with Pt/Ti/Au gate metallization, even up to -100V, which was the instrumental limitation in this experiment. After the off-state stressing, the drain current of Ni/Au gated-HEMTs decreased by~ 15%. For the Pt-gate HEMTs, no degradation of the drain current occurred and there were minimal changes in the Schottky gate characteristics for both forward and reverse bias conditions. The HEMTs with Pt/Ti/Au metallization showed an excellent drain on/off current ratio of 1.5 108. The on/off drain current ratio of Ni-gated HEMTs was dependent on the drain bias voltage and ranged from 1.2 107 at Vds=5V and 6 105

Liu, L. [University of Florida, Gainesville; Lo, C. F. [University of Florida; Kang, Tsung Sheng [University of Florida, Gainesville; Pearton, S. J. [University of Florida; Kravchenko, Ivan I [ORNL; Laboutin, O. [Kopin Corporation, Taunton, MA; Johnson, Wayne J. [Kopin Corporation, Taunton, MA; Ren, F. [University of Florida

2011-01-01T23:59:59.000Z

117

AOCS Official Method Tn 1a-64  

Science Conference Proceedings (OSTI)

Flash and Fire Points, Cleveland Open Cup Method AOCS Official Method Tn 1a-64 Methods Downloads Methods Downloads DEFINITION This method determines the temperature at which the test sample will flash and burn....

118

AOCS Official Method Tn 2a-86  

Science Conference Proceedings (OSTI)

Flash Point of Fatty Quaternary Ammonium Chloride, Closed Cup Method (Modified Closed Cup Method, ASTM Designation D 93-80) AOCS Official Method Tn 2a-86 Methods Downloads Methods Downloads DEFINITION This method

119

Invenergy TN LLC | Open Energy Information  

Open Energy Info (EERE)

Tennessee Sector Wind energy Product Wholly-owned subsidiary of Invenergy Wind developing wind farms in Tenessee. References Invenergy TN LLC1 LinkedIn Connections CrunchBase...

120

Investigation of mechanisms of multimode emission from double-heterostructure AlGaAs injection lasers with narrow stripe contacts  

SciTech Connect

An investigation was made of the spectral characteristics of planar stripe (contact width 6--8 ..mu..) lasers made of AlGaAs heterostructures. The steady-state emission spectrum could be of multimode type because of the high level of spontaneous emission in the lasing mode. The spectrum then became narrower on increase in the power and in the limit changed to the single-mode form. However, in the presence of self-modulation processes the multimode nature of the emission spectrum could be explained by a theory of transient effects and in this case the width of the spectrum increased on increase in the power.

Bessonov, Y.L.; Kurlenkov, S.S.; Morozov, V.N.; Sapozhnikov, S.M.; Thai, C.t.; Shidlovskii, V.R.

1985-02-01T23:59:59.000Z

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


121

C-V characteristics of epitaxial germanium metal-oxide-semiconductor capacitor on GaAs substrate with ALD Al2O3 dielectric  

Science Conference Proceedings (OSTI)

Epitaxial germanium metal-oxide-semiconductor capacitors (MOSCAP) were fabricated on GaAs substrate using atomic layer deposited Al"2O"3 gate dielectric with surface treatments including pure HF and HF plus rapid thermal oxidation (RTO). The electrical ... Keywords: ALD Al2O3, CMOS integration, Ge MOSCAP, Ge epitaxial film, RTO

Shih Hsuan Tang; Chien I. Kuo; Hai Dang Trinh; Mantu Hudait; Edward Yi Chang; Ching Yi Hsu; Yung Hsuan Su; Guang-Li Luo; Hong Quan Nguyen

2012-09-01T23:59:59.000Z

122

Lattice constant grading in the Al.sub.y Ga.sub.1-y As.sub.1-x Sb.sub.x alloy system  

DOE Patents (OSTI)

Liquid phase epitaxy is employed to grow a lattice matched layer of GaAsSb on GaAs substrates through the compositional intermediary of the III-V alloy system AlGaAsSb which acts as a grading layer. The Al constituent reaches a peak atomic concentration of about 6% within the first 2.5 .mu.m of the transition layer, then decreases smoothly to about 1% to obtain a lattice constant of 5.74 A. In the same interval the equilibrium concentration of Sb smoothly increases from 0 to about 9 atomic percent to form a surface on which a GaAsSb layer having the desired energy bandgap of 1.1 ev for one junction of an optimized dual junction photolvoltaic device. The liquid phase epitaxy is accomplished with a step cooling procedure whereby dislocation defects are more uniformly distributed over the surface of growing layer.

Moon, Ronald L. (Palo Alto, CA)

1980-01-01T23:59:59.000Z

123

Effects of proton irradiation on dc characteristics of InAlN/GaN high electron mobility transistors  

Science Conference Proceedings (OSTI)

The effects of proton irradiation on the dc characteristics of InAlN/GaN high electron mobility transistors were investigated. In this study we used 5 MeV protons with doses varying from 21011 to 21015 cm2. The transfer resistance and contact resistivity suffered more degradation as compared to the sheet resistance. With irradiation at the highest dose of 21015 cm2, both forward- and reverse-bias gate currents were increased after proton irradiation. A negative threshold-shift and reduction of the saturation drain current were also observed as a result of radiation-induced carrier scattering and carrier removal. Devices irradiated with doses of 21011 to 21015 cm2 exhibited minimal degradation of the saturation drain current and extrinsic trans- conductance. These results show that InAlN/GaN high electron mobility transistors are attractive for space-based applications when high-energy proton fluxes are present. VC 2011 American Vacuum Society. [DOI: 10.1116/1.3644480

Lo, C. F. [University of Florida; Liu, L. [University of Florida, Gainesville; Ren, F. [University of Florida; Kim, H.-Y. [Korea University; Kim, J. [Korea University; Pearton, S. J. [University of Florida; Laboutin, O. [Kopin Corporation, Taunton, MA; Cao, Yu [Kopin Corporation, Taunton, MA; Johnson, Wayne J. [Kopin Corporation, Taunton, MA; Kravchenko, Ivan I [ORNL

2011-01-01T23:59:59.000Z

124

DOE - Office of Legacy Management -- Knoxville Iron Co - TN 07  

Office of Legacy Management (LM)

Knoxville Iron Co - TN 07 Knoxville Iron Co - TN 07 FUSRAP Considered Sites Site: KNOXVILLE IRON CO. (TN.07 ) Eliminated from consideration under FUSRAP Designated Name: Not Designated Alternate Name: None Location: Knoxville , Tennessee TN.07-1 Evaluation Year: 1994 TN.07-2 TN.07-3 Site Operations: Melted uranium contaminated scrap metal in order to test industrial hygiene procedures in the mid-1950s. TN.07-1 Site Disposition: Eliminated - AEC license TN.07-2 Radioactive Materials Handled: Yes Primary Radioactive Materials Handled: Limited Quantities of Uranium Contained in Slag Material TN.07-4 Radiological Survey(s): Yes - health and safety monitoring during operations only TN.07-4 Site Status: Eliminated from consideration under FUSRAP Also see Documents Related to KNOXVILLE IRON CO.

125

Molecular beam epitaxy of InAlN lattice-matched to GaN with homogeneous composition using ammonia as nitrogen source  

Science Conference Proceedings (OSTI)

InAlN lattice-matched to GaN was grown by molecular beam epitaxy (MBE) using ammonia as the nitrogen source. The alloy composition, growth conditions, and strain coherence of the InAlN were verified by high resolution x-ray diffraction {omega}-2{theta} scans and reciprocal space maps. Scanning transmission electron microscopy and energy-dispersive x-ray spectroscopy of the InAlN revealed the absence of lateral composition modulation that was observed in the films grown by plasma-assisted MBE. InAlN/AlN/GaN high electron mobility transistors with smooth surfaces were fabricated with electron mobilities exceeding 1600 cm{sup 2}/Vs and sheet resistances below 244 {Omega}/sq.

Wong, Man Hoi; Wu Feng; Hurni, Christophe A.; Choi, Soojeong; Speck, James S.; Mishra, Umesh K. [Department of Electrical and Computer Engineering and Materials Department, University of California, Santa Barbara, California 93106 (United States)

2012-02-13T23:59:59.000Z

126

SOLID SOLUTION EFFECTS ON THE THERMAL PROPERTIES IN THE MgAl2O4-MgGa2O4  

Science Conference Proceedings (OSTI)

Solid solution eects on thermal conductivity within the MgO-Al2O3-Ga2O3 system were studied. Samples with systematically varied additions of MgGa2O4 to MgAl2O4 were prepared and the laser ash technique was used to determine thermal diusivity at temperatures between 200C and 1300C. Heat capacity as a function of temperature from room temperature to 800C was also determined using dierential scanning calorimetry. Solid solution in the MgAl2O4-MgGa2O4 system decreases the thermal conductivity up to 1000C. At 200C thermal conductivity decreased 24% with a 5 mol% addition of MgGa2O4 to the system. At 1000C the thermal conductivity decreased 13% with a 5 mol% addition. Steady state calculations showed a 12.5% decrease in heat ux with 5 mol% MgGa2O4 considered across a 12 inch thickness.

O'Hara, Kelley [University of Missouri, Rolla; Smith, Jeffrey D [ORNL; Sander, Todd P. [Missouri University of Science and Technology; Hemrick, James Gordon [ORNL

2013-01-01T23:59:59.000Z

127

Radio-frequency measurements of UNiX compounds (X= Al, Ga, Ge) in high magnetic fields  

SciTech Connect

We performed radio-frequency (RF) skin-depth measurements of antiferromagnetic UNiX compounds (X=Al, Ga, Ge) in magnetic fields up to 60 T and at temperatures between 1.4 to {approx}60 K. Magnetic fields are applied along different crystallographic directions and RF penetration-depth was measured using a tunnel-diode oscillator (TDO) circuit. The sample is coupled to the inductive element of a TDO resonant tank circuit, and the shift in the resonant frequency {Delta}f of the circuit is measured. The UNiX compounds exhibit field-induced magnetic transitions at low temperatures, and those transitions are accompanied by a drastic change in {Delta}f. The results of our skin-depth measurements were compared with previously published B-T phase diagrams for these three compounds.

Mielke, Charles H [Los Alamos National Laboratory; Mcdonald, David R [Los Alamos National Laboratory; Zapf, Vivien [Los Alamos National Laboratory; Altarawneh, Moaz M [Los Alamos National Laboratory; Lacerda, Alex H [Los Alamos National Laboratory; Adak, Sourav [Los Alamos National Laboratory; Karunakar, Kothapalli [Los Alamos National Laboratory; Nakotte, Heinrich [Los Alamos National Laboratory; Chang, S [NIST; Alsmadi, A M [HASHEMITE UNIV; Alyones, S [HASHEMIT UNIV

2009-01-01T23:59:59.000Z

128

The effects of proton irradiation on the reliability of InAlN/GaN high electron mobility transistors  

Science Conference Proceedings (OSTI)

We have investigated the effect of proton irradiation on reliability of InAlN/GaN high electron mobility transistors (HEMTs). Devices were subjected to 5-15 MeV proton irradiations with a fixed dose of 5 1015 cm-2, or to a different doses of 2 1011, 5 1013 or 2 1015 cm-2 of protons at a fixed energy of 5 MeV. During off-state electrical stressing, the typical critical voltage for un-irradiated devices was 45 to 55 V. By sharp contrast, no critical voltage was detected for proton irradiated HEMTs up to 100 V, which was instrument-limited. After electrical stressing, no degradation was observed for the drain or gate current-voltage characteristics of the proton-irradiated HEMTs. However, the drain current decreased ~12%, and the reverse bias gate leakage current increased more than two orders of magnitude for un-irradiated HEMTs as a result of electrical stressing.

Liu, L. [University of Florida, Gainesville; Lo, C. F. [University of Florida; Xi, Y. Y. [University of Florida, Gainesville; Wang, Y.l. [University of Florida; Kim, H.-Y. [Korea University; Kim, J. [Korea University; Pearton, S. J. [University of Florida; Laboutin, O. [Kopin Corporation, Taunton, MA; Cao, Yu [Kopin Corporation, Taunton, MA; Johnson, Wayne J. [Kopin Corporation, Taunton, MA; Kravchenko, Ivan I [ORNL; Ren, F. [University of Florida

2012-01-01T23:59:59.000Z

129

Atomic layer deposition of Al{sub 2}O{sub 3} on GaSb using in situ hydrogen plasma exposure  

SciTech Connect

In this report, we study the effectiveness of hydrogen plasma surface treatments for improving the electrical properties of GaSb/Al{sub 2}O{sub 3} interfaces. Prior to atomic layer deposition of an Al{sub 2}O{sub 3} dielectric, p-GaSb surfaces were exposed to hydrogen plasmas in situ, with varying plasma powers, exposure times, and substrate temperatures. Good electrical interfaces, as indicated by capacitance-voltage measurements, were obtained using higher plasma powers, longer exposure times, and increasing substrate temperatures up to 250 Degree-Sign C. X-ray photoelectron spectroscopy reveals that the most effective treatments result in decreased SbO{sub x}, decreased Sb, and increased GaO{sub x} content at the interface. This in situ hydrogen plasma surface preparation improves the semiconductor/insulator electrical interface without the use of wet chemical pretreatments and is a promising approach for enhancing the performance of Sb-based devices.

Ruppalt, Laura B.; Cleveland, Erin R.; Champlain, James G.; Prokes, Sharka M.; Brad Boos, J.; Park, Doewon; Bennett, Brian R. [Electronics Science and Technology Division, Naval Research Laboratory, Washington, DC 20375 (United States)

2012-12-03T23:59:59.000Z

130

Molecular beam epitaxial growth of metamorphic AlInSb/GaInSb high-electron-mobility-transistor structures on GaAs substrates for low power and high frequency applications  

Science Conference Proceedings (OSTI)

We report on molecular beam epitaxial growth of AlInSb/GaInSb metamorphic high-electron-mobility-transistor structures for low power, high frequency applications on 4 in. GaAs substrates. The structures consist of a Ga{sub 0.4}In{sub 0.6}Sb channel embedded in Al{sub 0.4}In{sub 0.6}Sb barrier layers which are grown on top of an insulating metamorphic buffer, which is based on the linear exchange of Ga versus In and a subsequent exchange of As versus Sb. Precise control of group V fluxes and substrate temperature in the Al{sub 0.4}In{sub 0.6}As{sub 1-x}Sb{sub x} buffer is essential to achieve high quality device structures. Good morphological properties were achieved demonstrated by the appearance of crosshatching and root mean square roughness values of 2.0 nm. Buffer isolation is found to be >100 k{Omega}/{open_square} for optimized growth conditions. Hall measurements at room temperature reveal electron densities of 2.8x10{sup 12} cm{sup -2} in the channel at mobility values of 21.000 cm{sup 2}/V s for single-sided Te volume doping and 5.4x10{sup 12} cm{sup -2} and 17.000 cm{sup 2}/V s for double-sided Te {delta}-doping, respectively.

Loesch, R.; Aidam, R.; Kirste, L.; Leuther, A. [Fraunhofer Institute for Applied Solid-State Physics (IAF), Tullastrasse 72, 79108 Freiburg (Germany)

2011-02-01T23:59:59.000Z

131

Capped ED-Mode AlN/GaN Inverters - Programmaster.org  

Science Conference Proceedings (OSTI)

The demonstrated inverter is operating at VDD = 5 V and consists of an enhancement- and depletion-mode HEMT with 1.5 nm thin subcritical AlN ...

132

Many-body effects in wide parabolic AlGaAs quantum wells A. Tabata, M. R. Martins, and J. B. B. Oliveira  

E-Print Network (OSTI)

Many-body effects in wide parabolic AlGaAs quantum wells A. Tabata, M. R. Martins, and J. B. B gas in n-type wide parabolic quantum wells. A series of samples with different well widths at the Fermi level at low temperature only in the thinnest parabolic quantum wells. The suppression of the many

Gusev, Guennady

133

Electrical properties and interfacial chemical environments of in situ atomic layer deposited Al2O3 on freshly molecular beam epitaxy grown GaAs  

Science Conference Proceedings (OSTI)

Interfacial chemical analyses and electrical characterization of in situ atomic layer deposited (ALD) Al"2O"3 on freshly molecular beam epitaxy (MBE) grown n- and p- GaAs (001) with a (4x6) surface reconstruction are performed. The capacitance-voltage ... Keywords: Atomic layer deposition, III-V compound semiconductor, Molecular beam epitaxy

Y. H. Chang; M. L. Huang; P. Chang; C. A. Lin; Y. J. Chu; B. R. Chen; C. L. Hsu; J. Kwo; T. W. Pi; M. Hong

2011-04-01T23:59:59.000Z

134

AlGaN UV LED and Photodiodes Radiation Hardness and Space Qualifications and Their Applications in Space Science and High Energy Density Physics  

Science Conference Proceedings (OSTI)

This presentation provides an overview of robust, radiation hard AlGaN optoelectronic devices and their applications in space exploration & high energy density physics. Particularly, deep UV LED and deep UV photodiodes are discussed with regard to their applications, radiation hardness and space qualification. AC charge management of UV LED satellite payload instruments, which were to be launched in late 2012, is covered.

Sun, K. X.

2011-05-31T23:59:59.000Z

135

Correlation between Ga-O signature and midgap states at the Al{sub 2}O{sub 3}/In{sub 0.53}Ga{sub 0.47}As interface  

SciTech Connect

Al{sub 2}O{sub 3}/In{sub 0.53}Ga{sub 0.47}As gate stacks were fabricated using different concentrations of NH{sub 4}OH as a pre-deposition treatment. Increased NH{sub 4}OH concentrations significantly reduced the C-V weak inversion hump and the measured near midgap interface states density (D{sub it}). X-ray photoelectron spectroscopy (XPS) studies revealed that these changes in the electrical properties were accompanied by a reduction in the amount of the Ga-O bonding while As-As dimers as well as other XPS detected InGaAs surface species did not correlate with the observed D{sub it} trend. Possible explanations for these findings are suggested.

Krylov, Igor [Russell Berrie Nanotechnology Institute, Technion - Israel Institute of Technology, Haifa 32000 (Israel); Gavrilov, Arkady [Department of Electrical Engineering, Technion - Israel Institute of Technology, Haifa 32000 (Israel); Eizenberg, Moshe [Russell Berrie Nanotechnology Institute, Technion - Israel Institute of Technology, Haifa 32000 (Israel); Department of Materials Engineering, Technion - Israel Institute of Technology, Haifa 32000 (Israel); Ritter, Dan [Russell Berrie Nanotechnology Institute, Technion - Israel Institute of Technology, Haifa 32000 (Israel); Department of Electrical Engineering, Technion - Israel Institute of Technology, Haifa 32000 (Israel)

2012-08-06T23:59:59.000Z

136

Structural and optical studies of GaN pn-junction with AlN buffer layer grown on Si (111) by RF plasma enhanced MBE  

Science Conference Proceedings (OSTI)

GaN pn-junction grown on silicon substrates have been the focus in a number of recent reports and further effort is still necessary to improve its crystalline quality for practical applications. GaN has the high n-type background carrier concentration resulting from native defects commonly thought to be nitrogen vacancies. In this work, we present the growth of pn-junction of GaN on Si (111) substrate using RF plasma-enhanced molecular beam epitaxy (MBE). Both of the layers show uniformity with an average thickness of 0.709 {mu}m and 0.095 {mu}m for GaN and AlN layers, respectively. The XRD spectra indicate that no sign of cubic phase of GaN are found, so it is confirmed that the sample possessed hexagonal structure. It was found that all the allowed Raman optical phonon modes of GaN, i.e. the E2 (low), E1 (high) and A1 (LO) are clearly visible.

Yusoff, Mohd Zaki Mohd; Hassan, Zainuriah; Woei, Chin Che; Hassan, Haslan Abu; Abdullah, Mat Johar [Nano-Optoelectronics Research and Technology Laboratory School of Physics, Universiti Sains Malaysia, 11800 Penang, Malaysia and Department of Applied Sciences Universiti Teknologi MARA (UiTM) 13500 Permatang Pauh, Penang (Malaysia); Department of Applied Sciences Universiti Teknologi MARA (UiTM) 13500 Permatang Pauh, Penang (Malaysia)

2012-06-29T23:59:59.000Z

137

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

138

Synchrotron radiation based cross-sectional scanning photoelectron microscopy and spectroscopy of n-ZnO:Al/p-GaN:Mg heterojunction  

Science Conference Proceedings (OSTI)

Al-doped ZnO (AZO) deposited by radio frequency co-sputtering is formed on epitaxial Mg-doped GaN template at room temperature to achieve n-AZO/p-GaN heterojunction. Alignment of AZO and GaN bands is investigated using synchrotron radiation based cross-sectional scanning photoelectron microscopy and spectroscopy on the nonpolar side-facet of a vertically c-axis aligned heterostructure. It shows type-II band configuration with valence band offset of 1.63 {+-} 0.1 eV and conduction band offset of 1.61 {+-} 0.1 eV, respectively. Rectification behavior is clearly observed, with a ratio of forward-to-reverse current up to six orders of magnitude when the bias is applied across the p-n junction.

Lee, Kai-Hsuan; Chen, Chia-Hao [Nano Science Group, National Synchrotron Radiation Research Center, Hsin-Ann Rd. 101, 30076 Hsinchu, Taiwan (China)] [Nano Science Group, National Synchrotron Radiation Research Center, Hsin-Ann Rd. 101, 30076 Hsinchu, Taiwan (China); Chang, Ping-Chuan [Department of Electro-Optical Engineering, Kun Shan University, Dawan Rd. 949, 71003 Tainan, Taiwan (China)] [Department of Electro-Optical Engineering, Kun Shan University, Dawan Rd. 949, 71003 Tainan, Taiwan (China); Chen, Tse-Pu; Chang, Sheng-Po; Chang, Shoou-Jinn [Institute of Microelectronics and Department of Electrical Engineering, Center for Micro/Nano Science and Technology, Advanced Optoelectronic Technology Center, National Cheng Kung University, University Rd. 1, 70101 Tainan, Taiwan (China)] [Institute of Microelectronics and Department of Electrical Engineering, Center for Micro/Nano Science and Technology, Advanced Optoelectronic Technology Center, National Cheng Kung University, University Rd. 1, 70101 Tainan, Taiwan (China); Shiu, Hung-Wei; Chang, Lo-Yueh [Nano Science Group, National Synchrotron Radiation Research Center, Hsin-Ann Rd. 101, 30076 Hsinchu, Taiwan (China) [Nano Science Group, National Synchrotron Radiation Research Center, Hsin-Ann Rd. 101, 30076 Hsinchu, Taiwan (China); Department of Physics, National Tsing Hua University, Kuang-Fu Rd. 101, 30013 Hsinchu, Taiwan (China)

2013-02-18T23:59:59.000Z

139

SiN{sub x}-induced intermixing in AlInGaAs/InP quantum well through interdiffusion of group III atoms  

Science Conference Proceedings (OSTI)

We analyze the composition profiles within intermixed and non-intermixed AlInGaAs-based multiple quantum wells structures by secondary ion mass spectrometry and observe that the band gap blue shift is mainly attributed to the interdiffusion of In and Ga atoms between the quantum wells and the barriers. Based on these results, several AlInGaAs-based single quantum well (SQW) structures with various compressive strain (CS) levels were grown and their photoluminescence spectra were investigated after the intermixing process involving the encapsulation of thin SiN{sub x} dielectric films on the surface followed by rapid thermal annealing. In addition to the annealing temperature, we report that the band gap shift can be also enhanced by increasing the CS level in the SQW. For instance, at an annealing temperature of 850 Degree-Sign C, the photoluminescence blue shift is found to reach more than 110 nm for the sample with 1.2%-CS SQW, but only 35 nm with 0.4%-CS SQW. We expect that this relatively larger atomic compositional gradient of In (and Ga) between the compressively strained quantum well and the barrier can facilitate the atomic interdiffusion and it thus leads to the larger band gap shift.

Lee, Ko-Hsin; Thomas, Kevin; Gocalinska, Agnieszka; Manganaro, Marina; Corbett, Brian [Tyndall National Institute, University College Cork, Lee Maltings, Prospect Row, Cork (Ireland); Pelucchi, Emanuele; Peters, Frank H. [Tyndall National Institute, University College Cork, Lee Maltings, Prospect Row, Cork (Ireland); Department of Physics, University College Cork, Cork (Ireland)

2012-11-01T23:59:59.000Z

140

Lateral Al{sub x}Ga{sub 1-x}N power rectifiers with 9.7 kV reverse breakdown voltage  

SciTech Connect

Al{sub x}Ga{sub 1-x}N (x=0--0.25) Schottky rectifiers were fabricated in a lateral geometry employing p{sup +}-implanted guard rings and rectifying contact overlap onto an SiO{sub 2} passivation layer. The reverse breakdown voltage (V{sub B}) increased with the spacing between Schottky and ohmic metal contacts, reaching 9700 V for Al{sub 0.25}Ga{sub 0.75}N and 6350 V for GaN, respectively, for 100 {mu}m gap spacing. Assuming lateral depletion, these values correspond to breakdown field strengths of {<=}9.67x10{sup 5}Vcm{sup -1}, which is roughly a factor of 20 lower than the theoretical maximum in bulk GaN. The figure of merit (V{sub B}){sup 2}/R{sub ON}, where R{sub ON} is the on-state resistance, was in the range 94--268 MWcm-2 for all the devices.

Zhang, A. P.; Johnson, J. W.; Ren, F.; Han, J.; Polyakov, A. Y.; Smirnov, N. B.; Govorkov, A. V.; Redwing, J. M.; Lee, K. P.; Pearton, S. J.

2001-02-05T23:59:59.000Z

Note: This page contains sample records for the topic "tn al ga" 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

Proton irradiation energy dependence of dc and rf characteristics on InAlN/GaN high electron mobility transistors  

Science Conference Proceedings (OSTI)

The effects of proton irradiation energy on dc and rf characteristics of InAlN/GaN high electron mobility transistors (HEMTs) were investigated. A fixed proton dose of 51015 cm2 with 5, 10, and 15 MeV irradiation energies was used in this study. For the dc characteristics, degradation was observed for sheet resistance, transfer resistance, contact resistivity, saturation drain current, maximum transconductance, reverse-bias gate leakage current, and sub-threshold drain leakage current for all the irradiated HEMTs; however, the degree of the degradation was decreased as the irradiation energy increased. Similar trends were obtained for the rf performance of the devices, with 10% degradation of the unity gain cut-off frequency (fT) and maximum oscillation frequency ( fmax) for the HEMTs irradiated with 15 MeV protons but 30% for 5 MeV proton irradiation. The carrier removal rate was in the range 0.66 1.24 cm1 over the range of proton energies investigated

Lo, C. F. [University of Florida; Liu, L. [University of Florida, Gainesville; Ren, F. [University of Florida; Pearton, S. J. [University of Florida; Gila, Brent P. [University of Florida, Gainesville; Kim, H.-Y. [Korea University; Kim, J. [Korea University; Laboutin, O. [Kopin Corporation, Taunton, MA; Cao, Yu [Kopin Corporation, Taunton, MA; Johnson, Wayne J. [Kopin Corporation, Taunton, MA; Kravchenko, Ivan I [ORNL

2012-01-01T23:59:59.000Z

142

Above room-temperature operation of InAs/AlGaSb superlattice quantum cascade lasers emitting at 12 {mu}m  

SciTech Connect

The authors report on above-room-temperature operation of InAs/AlGaSb quantum cascade lasers emitting at 12 {mu}m. The laser structures are grown on a n-InAs (100) substrate using solid-source molecular beam epitaxy. An InAs/AlGaSb superlattice is used as an active part and an InAs double plasmon waveguide is used for optical confinement. Results show that increased doping concentration in the injection part of the active region expands the current operation range of the devices, allowing laser operation at and above room temperature. The observed threshold current density is 4.0 kA/cm{sup 2} at 300 K; the maximum operation temperature is 340 K.

Ohtani, K.; Moriyasu, Y.; Ohnishi, H.; Ohno, H. [Laboratory for Nanoelectronics and Semiconductor Spintronics, Research Institute of Electrical Communication, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai 980-8577 (Japan)

2007-06-25T23:59:59.000Z

143

Analysis of the causes of the decrease in the electroluminescence efficiency of AlGaInN light-emitting-diode heterostructures at high pumping density  

SciTech Connect

The study is devoted to theoretical explanation of a decrease in the electroluminescence efficiency as the pump current increases, which is characteristic of light-emitting-diode (LED) heterostructures based on AlInGaN. Numerical simulation shows that the increase in the external quantum efficiency at low current densities J {approx} 1 A/cm{sup 2} is caused by the competition between radiative and nonradiative recombination. The decrease in the quantum efficiency at current densities J > 1 A/cm{sup 2} is caused by a decrease in the efficiency of hole injection into the active region. It is shown that the depth of the acceptor energy level in the AlGaN emitter, as well as low electron and hole mobilities in the p-type region, plays an important role in this effect. A modified LED heterostructure is suggested in which the efficiency decrease with the pump current should not occur.

Rozhansky, I. V., E-mail: igor@quantum.ioffe.ru; Zakheim, D. A. [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation)

2006-07-15T23:59:59.000Z

144

GaN High Power Devices  

SciTech Connect

A brief review is given of recent progress in fabrication of high voltage GaN and AlGaN rectifiers, GaN/AlGaN heterojunction bipolar transistors, GaN heterostructure and metal-oxide semiconductor field effect transistors. Improvements in epitaxial layer quality and in fabrication techniques have led to significant advances in device performance.

PEARTON,S.J.; REN,F.; ZHANG,A.P.; DANG,G.; CAO,X.A.; LEE,K.P.; CHO,H.; GILA,B.P.; JOHNSON,J.W.; MONIER,C.; ABERNATHY,C.R.; HAN,JUNG; BACA,ALBERT G.; CHYI,J.-I.; LEE,C.-M.; NEE,T.-E.; CHUO,C.-C.; CHI,G.C.; CHU,S.N.G.

2000-07-17T23:59:59.000Z

145

Accelerated Publication: Ge metal-oxide-semiconductor devices with Al2O3/Ga2O3(Gd2O3) as gate dielectric  

Science Conference Proceedings (OSTI)

Ga"2O"3(Gd"2O"3) [GGO] 3.5nm-thick, with an in situ Al"2O"3 cap 1.5nm thick, has been directly deposited on Ge substrate without employing interfacial passivation layers. The equivalent oxide thickness (EOT) of the gate stack is 1.38-nm. The metal-oxide-semiconductor ... Keywords: EOT, Germanium, High-? dielectric, MOS

L. K. Chu; T. H. Chiang; T. D. Lin; Y. J. Lee; R. L. Chu; J. Kwo; M. Hong

2012-03-01T23:59:59.000Z

146

Well-defined excited states of self-assembled InAs/InAlGaAs quantum dots on InP (001)  

SciTech Connect

Self-assembled InAs/InAlGaAs quantum dots (QDs) in an InAlGaAs matrix on InP (001) substrates were grown by the alternate growth method (AGQD), where an InAs layer with a thickness of 1 monolayer (ML) and an InAlGaAs layer with a thickness of 1 ML were alternately deposited. Cross-sectional transmission electron microscopy images indicated that the aspect ratio (height/width) for the AGQDs was {approx}0.25, which was higher than {approx}0.10 of conventionally grown InAs QDs. The photoluminescence (PL) peak position for the ground states of the AGQDs was 1.485 {mu}m with a linewidth broadening of 42 meV at room temperature, while the PL linewidth for the conventionally grown QDs was 85 meV. And the peaks for the excited-state transitions were also clearly observed from the excitation-power dependent PL. This is the first observation on the well-defined excited-state transitions from the InP-based InAs QDs, even though there were several reports on the features of the excited states.

Kim, Jin Soo; Lee, Jin Hong; Hong, Sung Ui; Kwack, Ho-Sang; Choi, Byung Seok; Oh, Dae Kon [Basic Research Laboratory, Electronics and Telecommunications Research Institute (ETRI), Daejeon (Korea, Republic of)

2005-08-01T23:59:59.000Z

147

Optical properties of a-plane (Al, Ga)N/GaN multiple quantum wells grown on strain engineered Zn{sub 1-x}Mg{sub x}O layers by molecular beam epitaxy  

Science Conference Proceedings (OSTI)

Nonpolar (1120) Al{sub 0.2}Ga{sub 0.8}N/GaN multiple quantum wells (MQWs) have been grown by molecular beam epitaxy on (1120) Zn{sub 0.74}Mg{sub 0.26}O templates on r-plane sapphire substrates. The quantum wells exhibit well-resolved photoluminescence peaks in the ultra-violet region, and no sign of quantum confined Stark effect is observed in the complete multiple quantum well series. The results agree well with flat band quantum well calculations. Furthermore, we show that the MQW structures are strongly polarized along the [0001] direction. The origin of the polarization is discussed in terms of the strain anisotropy dependence of the exciton optical oscillator strengths.

Xia, Y.; Vinter, B.; Chauveau, J.-M. [CRHEA-CNRS, Rue Bernard Gregory, 06560 Valbonne (France); University of Nice Sophia-Antipolis, 06103 Nice (France); Brault, J.; Nemoz, M.; Teisseire, M.; Leroux, M. [CRHEA-CNRS, Rue Bernard Gregory, 06560 Valbonne (France)

2011-12-26T23:59:59.000Z

148

AT-TN: Mr. R. L. Rudolph  

Office of Legacy Management (LM)

MAR 1 ? 7982 MAR 1 ? 7982 3echW tiational, Inc. AT-TN: Mr. R. L. Rudolph PO Box 350 Oak Ridge, TFi 37830 Gentlemen: CRITERIA FOR REMEDIAL ACTION AT ACID/PUEBLO AND BAY0 CANYONS; REQUEST FOR COST/BENEFIT ANALYSES OF REMEDIAL ACTION OPTIONS AT THE CANYONS Enclosed are several pieces of cqrespondence related to AcldjPueblo * and Bayo Canyons. . . . . . . . . . . . . . First, EP has concurred with the remedial action DATE criteria for the New Mexico sftes that were proposed to them on August 20, 1987 (wfth the addition of a criterion for Pu-239 added RTG SYMBO, October 20, 7981). In summary, the cri terla will be: . . . . . . . IUITI*LSSIG. f ---- Radionuclfdt Sr-90 cs-137 Th-228 Th-230 Th-232 u-234 U-238 Pu-239 Pu-240 Pu-241 Am-241 Sofl Limft (pCi/g) 100 80

149

SLAC_TN04051_04.dvi  

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

8 8 SLAC-TN-04-051 Sep. 2004 (Jan. 2005) Abstract This note documents a set of expressions used to explore the issue of whether or not it is reasonable to consider a conventional positron source for a Tesla formatted beam. The critical issue is that of energy deposition in the conversion target and the comparison of the induced stress with the ultimate tensile strength of the target material. Since the length of the incident beam pulse is large in comparison to the ratio of beam size to the speed of sound, the concurrent pressure pulse dissipates in a time short compared to the overall pulse duration and one is left with only the Electron Conditioning of Technical Aluminum Surfaces ¤ F. Le Pimpec, F. King, and R. E. Kirby

150

Long-wavelength laser based on self-assembled InAs quantum dots in InAlGaAs on InP (001)  

SciTech Connect

Seven stacks of self-assembled InAs quantum dots (QDs) separated by 28 nm thick InAlGaAs barriers were grown on InP (001) substrate by a solid-source molecular-beam epitaxy and were investigated by cross-sectional transmission electron microscopy and photoluminescence spectroscopy. Gain guided broad-area lasers with a stripe width of 75 {mu}m were fabricated by using the seven-stacked InAs QD layers with the InAlGaAs-InAlAs material system on InP (001). The lasing operation from InAs QDs was observed up to 260 K and the characteristic temperature of the uncoated QD laser calculated from the temperature dependence of threshold current density was 377 K for temperatures up to 200 K, and 138 K above 200 K. The drastic decrease in the characteristic temperature above 200 K was mainly related to the thermal behavior of carriers in QDs, and possibly the thermal coupling of the QDs to the wetting layer and the waveguide region.

Kim, Jin Soo; Lee, Jin Hong; Hong, Sung Ui; Han, Won Seok; Kwack, Ho-Sang; Lee, Chul Wook; Oh, Dae Kon [Basic Research Laboratory, Electronics and Telecommunications Research Institute (ETRI), Daejeon (Korea, Republic of)

2004-08-09T23:59:59.000Z

151

LBNL-4183E-rev1 N NA AT TU UR RA AL L G GA AS S V VA AR RI  

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

4183E-rev1 4183E-rev1 N NA AT TU UR RA AL L G GA AS S V VA AR RI IA AB BI IL LI IT TY Y I IN N C CA AL LI IF FO OR RN NI IA A: : E EN NV VI IR RO ON NM ME EN NT TA AL L I IM MP PA AC CT TS S A AN ND D D DE EV VI IC CE E P PE ER RF FO OR RM MA AN NC CE E E EX XP PE ER RI IM ME EN NT TA AL L E EV VA AL LU UA AT TI IO ON N O OF F I IN NS ST TA AL LL LE ED D C CO OO OK KI IN NG G E EX XH HA AU US ST T F FA AN N P PE ER RF FO OR RM MA AN NC CE E Brett C. Singer, William W. Delp and Michael G. Apte Indoor Environment Department Atmospheric Sciences Department Environmental Energy Technologies Division July 2011 (Revised February 2012) Disclaimer 1 This document was prepared as an account of work sponsored by the United States Government. While this document is believed to contain correct information, neither the United States Government nor any agency thereof, nor The Regents of the University of California, nor any of

152

DOE - Office of Legacy Management -- Oak Ridge TN Warehouse Site...  

Office of Legacy Management (LM)

Warehouses Site. This site is managed by the U.S. Department of Energy Office of Legacy Management. Aerial photograph of the Oak Ridge, Tennessee, Site TN.09-1 - DOE...

153

Passivation of In{sub 0.53}Ga{sub 0.47}As/ZrO{sub 2} interfaces by AlN atomic layer deposition process  

SciTech Connect

Reducing defects at III-V/high-k interfaces is essential for optimizing devices built on these materials. Here, the role of an interfacial AlN process at In{sub 0.53}Ga{sub 0.47}As/ZrO{sub 2} interfaces is investigated by hard x-ray photoelectron spectroscopy (HAXPES) and capacitance/voltage (C-V) measurements. C-V measurements show a significant reduction in the density of interface traps with the interfacial AlN process and a capping TiN layer. To elucidate the specific role of the AlN process, blanket films with various deposition processes are compared. The AlN process alone (without subsequent dielectric deposition) reduces InGaAs oxide levels below the HAXPES detection limit, even though the AlN is ultimately found to be oxidized into AlO{sub x} with only trace N incorporation, yet AlN passivation provides a lower D{sub it} (density of interface traps) when compared with an H{sub 2}O-based Al{sub 2}O{sub 3} deposition. The AlN process does not passivate against re-oxidation of the InGaAs during an O{sub 3} based ZrO{sub 2} deposition process, but it does provide passivation against As-As development during subsequent TiN deposition. The role of chemical defects in the C-V characteristics is also discussed.

Weiland, C.; Woick, J. C. [National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Rumaiz, A. K. [National Synchrotron Light Source, Brookhaven National Laboratory, Upton, New York 11973 (United States); Price, J.; Lysaght, P. [SEMATECH, 257 Fuller Road, Albany, New York 12203 (United States)

2013-07-21T23:59:59.000Z

154

Thickness Effect of Al-Doped ZnO Window Layer on Damp-Heat Stability of CuInGaSe2 Solar Cells  

DOE Green Energy (OSTI)

We investigated the damp heat (DH) stability of CuInGaSe{sub 2} (CIGS) solar cells as a function of thickness of the Al-doped ZnO (AZO) window layer from the 'standard' 0.12 {micro}m to a modest 0.50 {micro}m over an underlying 0.10-{micro}m intrinsic ZnO buffer layer. The CIGS cells were prepared with external electrical contact using fine Au wire to the tiny 'standard' Ni/Al (0.05 {micro}m/3 {micro}m) metal grid contact pads. Bare cell coupons and sample sets encapsulated in a specially designed, Al-frame test structure with an opening for moisture ingress control using a TPT backsheet were exposed to DH at 85 C and 85% relative humidity, and characterized by current-voltage (I-V), quantum efficiency (QE), and (electrochemical) impedance spectroscopy (ECIS). The results show that bare cells exhibited rapid degradation within 50-100 h, accompanied by film wrinkling and delamination and corrosion of Mo and AlNi grid, regardless of AZO thickness. In contrast, the encapsulated cells did not show film wrinkling, delamination, and Mo corrosion after 168 h DH exposure; but the trend of efficiency degradation rate showed a weak correlation to the AZO thickness.

Pern, F. J.; Mansfield, L.; DeHart, C.; Glick, S. H.; Yan, F.; Noufi, R.

2011-01-01T23:59:59.000Z

155

Thickness Effect of Al-Doped ZnO Window Layer on Damp Heat Stability of CuInGaSe2 Solar Cells: Preprint  

DOE Green Energy (OSTI)

We investigated the damp heat (DH) stability of CuInGaSe2 (CIGS) solar cells as a function of thickness of the Al-doped ZnO (AZO) window layer from the 'standard' 0.12 ?m to a modest 0.50 ?m over an underlying 0.10-?m intrinsic ZnO buffer layer. The CIGS cells were prepared with external electrical contact using fine Au wire to the tiny 'standard' Ni/Al (0.05 ?m/3 ?m) metal grid contact pads. Bare cell coupons and sample sets encapsulated in a specially designed, Al-frame test structure with an opening for moisture ingress control using a TPT backsheet were exposed to DH at 85oC and 85% relative humidity, and characterized by current-voltage (I-V), quantum efficiency (QE), and (electrochemical) impedance spectroscopy (ECIS). The results show that bare cells exhibited rapid degradation within 50-100 h, accompanied by film wrinkling and delamination and corrosion of Mo and AlNi grid, regardless of AZO thickness. In contrast, the encapsulated cells did not show film wrinkling, delamination, and Mo corrosion after 168 h DH exposure; but the trend of efficiency degradation rate showed a weak correlation to the AZO thickness.

Pern, F. J.; Mansfield, L.; DeHart, C.; Glick, S. H.; Yan, F.; Noufi, R.

2011-07-01T23:59:59.000Z

156

DOE - Office of Legacy Management -- Vitro Corp of America - TN 04  

Office of Legacy Management (LM)

TN 04 TN 04 FUSRAP Considered Sites Site: Vitro Corp. of America (TN.04) Eliminated from further consideration under FUSRAP Designated Name: Not Designated Alternate Name: Heavy Minerals Company Vitro Chemical Company TN.04-4 TN.04-5 Location: 4000 North Hawthorne Street , Chattanooga , Tennessee TN.04-5 Evaluation Year: 1990 TN.04-1 Site Operations: Processed mineral monazite to produce a thorium-uranium hydroxide and a series of rare earth products. TN.04-4 Site Disposition: Eliminated - Site licensed by AEC and State of Tennessee - No Authority to perform remedial action under FUSRAP TN.04-2 TN.04-3 Radioactive Materials Handled: Yes Primary Radioactive Materials Handled: Thorium Metal, ThF4, Thorium Oxide TN.04-1 Radiological Survey(s): None Indicated

157

Impacts of anisotropic lattice relaxation on crystal mosaicity and luminescence spectra of m-plane Al{sub x}Ga{sub 1-x}N films grown on m-plane freestanding GaN substrates by NH{sub 3} source molecular beam epitaxy  

SciTech Connect

In-plane anisotropic lattice relaxation was correlated with the crystal mosaicity and luminescence spectra for m-plane Al{sub x}Ga{sub 1-x}N films grown on a freestanding GaN substrate by NH{sub 3}-source molecular beam epitaxy. The homoepitaxial GaN film exhibited A- and B-excitonic emissions at 8 K, which obeyed the polarization selection rules. For Al{sub x}Ga{sub 1-x}N overlayers, the m-plane tilt mosaic along c-axis was the same as the substrate as far as coherent growth was maintained (x{<=}0.25). However, it became more severe than along the a-axis for lattice-relaxed films (x{>=}0.52). The results are explained in terms of anisotropic lattice and thermal mismatches between the film and the substrate. Nonetheless, all the Al{sub x}Ga{sub 1-x}N films exhibited a near-band-edge emission peak and considerably weak deep emission at room temperature.

Hoshi, T.; Hazu, K.; Ohshita, K.; Kagaya, M.; Onuma, T.; Chichibu, S. F. [CANTech, Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577 (Japan); Fujito, K. [Optoelectronics Laboratory, Mitsubishi Chemical Corporation, 1000 Higashi-Mamiana, Ushiku 300-1295 (Japan); Namita, H. [Mitsubishi Chemical Group Science and Technology Research Center, Inc., 8-3-1 Chuo, Ami, Inashiki 300-0332 (Japan)

2009-02-16T23:59:59.000Z

158

Self-cleaning and surface recovery with arsine pretreatment in ex situ atomic-layer-deposition of Al2O3 on GaAs  

E-Print Network (OSTI)

. heavily doped GaAs 001 substrates at 650 °C with TMG Ga CH3 3 and arsine AsH3 V/III=23 with disilane Si2H6

159

Y2, Threading Defect Elimination in GaN Nanostructures  

Science Conference Proceedings (OSTI)

DD3, A New Approach to Make ZnO-Cu2O Heterojunctions for Solar Cells ... E2, AlGaAs/GaAs/GaN Wafer Fused HBTs with Ar Implanted Extrinsic Collectors.

160

Accelerated aging of GaAs concentrator solar cells  

DOE Green Energy (OSTI)

An accelerated aging study of AlGaAs/GaAs solar cells has been completed. The purpose of the study was to identify the possible degradation mechanisms of AlGaAs/GaAs solar cells in terrestrial applications. Thermal storage tests and accelerated AlGaAs corrosion studies were performed to provide an experimental basis for a statistical analysis of the estimated lifetime. Results of this study suggest that a properly designed and fabricated AlGaAs/GaAs solar cell can be mechanically rugged and environmentally stable with projected lifetimes exceeding 100 years.

Gregory, P.E.

1982-04-01T23:59:59.000Z

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161

Effective passivation of In{sub 0.2}Ga{sub 0.8}As by HfO{sub 2} surpassing Al{sub 2}O{sub 3} via in-situ atomic layer deposition  

SciTech Connect

High {kappa} gate dielectrics of HfO{sub 2} and Al{sub 2}O{sub 3} were deposited on molecular beam epitaxy-grown In{sub 0.2}Ga{sub 0.8}As pristine surface using in-situ atomic-layer-deposition (ALD) without any surface treatment or passivation layer. The ALD-HfO{sub 2}/p-In{sub 0.2}Ga{sub 0.8}As interface showed notable reduction in the interfacial density of states (D{sub it}), deduced from quasi-static capacitance-voltage and conductance-voltage (G-V) at room temperature and 100 Degree-Sign C. More significantly, the midgap peak commonly observed in the D{sub it}(E) of ALD-oxides/In{sub 0.2}Ga{sub 0.8}As is now greatly diminished. The midgap D{sub it} value decreases from {>=}15 Multiplication-Sign 10{sup 12} eV{sup -1} cm{sup -2} for ALD-Al{sub 2}O{sub 3} to {approx}2-4 Multiplication-Sign 10{sup 12} eV{sup -1} cm{sup -2} for ALD-HfO{sub 2}. Further, thermal stability at 850 Degree-Sign C was achieved in the HfO{sub 2}/In{sub 0.2}Ga{sub 0.8}As, whereas C-V characteristics of Al{sub 2}O{sub 3}/p-In{sub 0.2}Ga{sub 0.8}As degraded after the high temperature annealing. From in-situ x-ray photoelectron spectra, the AsO{sub x}, which is not the oxidized state from the native oxide, but is an induced state from adsorption of trimethylaluminum and H{sub 2}O, was found at the ALD-Al{sub 2}O{sub 3}/In{sub 0.2}Ga{sub 0.8}As interface, while that was not detected at the ALD-HfO{sub 2}/In{sub 0.2}Ga{sub 0.8}As interface.

Chang, Y. H.; Chiang, T. H. [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Lin, C. A.; Liu, Y. T.; Lin, H. Y.; Huang, M. L.; Kwo, J. [Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Lin, T. D.; Hong, M. [Graduate Institute of Applied Physics and Department of Physics, National Taiwan University, Taipei 10617, Taiwan (China); Pi, T. W. [National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan (China)

2012-10-22T23:59:59.000Z

162

Comparison of the properties of AlGaInN light-emitting diode chips of vertical and flip-chip design using silicon as the a submount  

SciTech Connect

Vertical and flip-chip light-emitting diode (LED) chips are compared from the viewpoint of the behavior of current spreading in the active region and the distribution of local temperatures and thermal resistances of chips. AlGaInN LED chips of vertical design are fabricated using Si as a submount and LED flipchips were fabricated with the removal of a sapphire substrate. The latter are also mounted on a Si submount. The active regions of both chips are identical and are about 1 mm{sup 2} in size. It is shown that both the emittance of the crystal surface in the visible range and the distribution of local temperatures estimated from radiation in the infrared region are more uniform in crystals of vertical design. Heat removal from flip-chips is insufficient in regions of the n contact, which do not possess good thermal contact with the submount. As a result, the total thermal resistances between the p-n junction and the submount both for the vertical chips and for flip-chips are approximately 1 K/W. The total area of the flip-chips exceeds that of the vertical design chips by a factor of 1.4.

Markov, L. K., E-mail: l.markov@mail.ioffe.ru; Smirnova, I. P.; Pavlyuchenko, A. S. [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation); Kukushkin, M. V.; Vasil'eva, E. D. [ZAO Innovation 'Tetis' (Russian Federation); Chernyakov, A. E. [Russian Academy of Sciences, Science-and-Technology Microelectronics Center (Russian Federation); Usikov, A. S. [De Core Nanosemiconductors Ltd. (India)

2013-03-15T23:59:59.000Z

163

Ga Air Compressor, Ga Air Compressor Products, Ga Air ...  

U.S. Energy Information Administration (EIA)

Ga Air Compressor, You Can Buy Various High Quality Ga Air Compressor Products from Global Ga Air Compressor Suppliers and Ga Air Compressor ...

164

GaSb molecular beam epitaxial growth on p-InP(001) and passivation with in situ deposited Al{sub 2}O{sub 3} gate oxide  

SciTech Connect

The integration of high carrier mobility materials into future CMOS generations is presently being studied in order to increase drive current capability and to decrease power consumption in future generation CMOS devices. If III-V materials are the candidates of choice for n-type channel devices, antimonide-based semiconductors present high hole mobility and could be used for p-type channel devices. In this work we first demonstrate the heteroepitaxy of fully relaxed GaSb epilayers on InP(001) substrates. In a second part, the properties of the Al{sub 2}O{sub 3}/GaSb interface have been studied by in situ deposition of an Al{sub 2}O{sub 3} high-{kappa} gate dielectric. The interface is abrupt without any substantial interfacial layer, and is characterized by high conduction and valence band offsets. Finally, MOS capacitors show well-behaved C-V with relatively low D{sub it} along the bandgap, these results point out an efficient electrical passivation of the Al{sub 2}O{sub 3}/GaSb interface.

Merckling, C.; Brammertz, G.; Hoffmann, T. Y.; Caymax, M.; Dekoster, J. [Interuniversity Microelectronics Center (IMEC vzw), Kapeldreef 75, 3001, Leuven (Belgium); Sun, X. [Katholieke Universiteit Leuven, Celestijnelaan 200D, 3001, Leuven (Belgium); Department of Electrical Engineering, Yale University, New Haven, Connecticut 06520-8284 (United States); Alian, A.; Heyns, M. [Interuniversity Microelectronics Center (IMEC vzw), Kapeldreef 75, 3001, Leuven (Belgium); Katholieke Universiteit Leuven, Celestijnelaan 200D, 3001, Leuven (Belgium); Afanas'ev, V. V. [Katholieke Universiteit Leuven, Celestijnelaan 200D, 3001, Leuven (Belgium)

2011-04-01T23:59:59.000Z

165

Electron transport in an In{sub 0.52}Al{sub 0.48}As/In{sub 0.53}Ga{sub 0.47}As/In{sub 0.52}Al{sub 0.48}As quantum well with a {delta}-Si doped barrier in high electric fields  

Science Conference Proceedings (OSTI)

The electron conduction in a two-dimensional channel of an In{sub 0.52}Al{sub 0.48}As/In{sub 0.53}Ga{sub 0.47}As/In{sub 0.52}Al{sub 0.48}As quantum well (QW) with a {delta}-Si doped barrier has been investigated. It is shown that the introduction of thin InAs barriers into the QW reduces the electron scattering rate from the polar optical and interface phonons localized in the QW and increases the electron mobility. It is found experimentally that the saturation of the conduction current in the In{sub 0.53}Ga{sub 0.47}As channel in strong electric fields is determined by not only the sublinear field dependence of the electron drift velocity, but also by the decrease in the electron concentration n{sub s} with an increase in the voltage across the channel. The dependence of n{sub s} on the applied voltage is due to the ionized-donor layer located within the {delta}-Si doped In{sub 0.52}Al{sub 0.48}As barrier and oriented parallel to the In{sub 0.53}Ga{sub 0.47}As QW.

Vasil'evskii, I. S.; Galiev, G. B.; Matveev, Yu. A.; Klimov, E. A.; Pozela, J., E-mail: pozela@pfi.lt [Russian Academy of Sciences, Institute of Microwave Semiconductor Electronics (Russian Federation); Pozela, K.; Suziedelis, A.; Paskevic, C.; Juciene, V. [Semiconductor Physics Institute (Lithuania)

2010-07-15T23:59:59.000Z

166

P8, Fabrication of Subwavelength Pillar Arrays on GaAs by Confined ...  

Science Conference Proceedings (OSTI)

DD3, A New Approach to Make ZnO-Cu2O Heterojunctions for Solar Cells ... E2, AlGaAs/GaAs/GaN Wafer Fused HBTs with Ar Implanted Extrinsic Collectors.

167

Y-12 and East TN Public Broadcasting System ? A Nuclear Family...  

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

East TN Public Broadcasting System - A Nuclear Family Video Miniseries The fourth and final episode of A Nuclear Family: Y-12 National Security Complex documentary film miniseries...

168

Structure and magnetic properties of the Al{sub 1-x}Ga{sub x}FeO{sub 3} family of oxides: A combined experimental and theoretical study  

Science Conference Proceedings (OSTI)

Magnetic properties of the Al{sub 1-x}Ga{sub x}FeO{sub 3} family of oxides crystallizing in a non-centrosymmetric space group have been investigated in detail along with structural aspects by employing X-ray and neutron diffraction, Moessbauer spectroscopy and other techniques. The study has revealed the occurrence of several interesting features related to unit cell parameters, site disorder and ionic size. Using first-principles density functional theory based calculations, we have attempted to understand how magnetic ordering and related properties in these oxides depend sensitively on disorder at the cation site. The origin and tendency of cations to disorder and the associated properties are traced to the local structure and ionic sizes. -- Graphical abstract: We have studied both experimentally and theoretically the important role of disorder at the cation site on magnetic and related properties of the Al{sub 1-x}Ga{sub x}FeO{sub 3} family of oxides crystallizing in a non-centrosymmetric space group. Display Omitted Research highlights: {yields} Interesting observations on cation site disorder, cell parameters and ionic size. {yields} Cation site disorder explains magnetic ordering. {yields} Demonstrates the importance of the A-site cations.

Saha, Rana; Shireen, Ajmala [Chemistry and Physics of Materials Unit, New Chemistry Unit, Theoretical Science Unit and International Centre for Materials Science, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560 064 (India); Bera, A.K. [Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Shirodkar, Sharmila N.; Sundarayya, Y.; Kalarikkal, Nandakumar [Chemistry and Physics of Materials Unit, New Chemistry Unit, Theoretical Science Unit and International Centre for Materials Science, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560 064 (India); Yusuf, S.M. [Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Waghmare, Umesh V. [Chemistry and Physics of Materials Unit, New Chemistry Unit, Theoretical Science Unit and International Centre for Materials Science, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560 064 (India); Sundaresan, A., E-mail: sundaresan@jncasr.ac.i [Chemistry and Physics of Materials Unit, New Chemistry Unit, Theoretical Science Unit and International Centre for Materials Science, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560 064 (India); Rao, C.N.R, E-mail: cnrrao@jncasr.ac.i [Chemistry and Physics of Materials Unit, New Chemistry Unit, Theoretical Science Unit and International Centre for Materials Science, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560 064 (India)

2011-03-15T23:59:59.000Z

169

II United States Government DATE: REPLY TO Al-TN OF: SUBJECT...  

Office of Legacy Management (LM)

for Remedial Action at the Former Baker Brothers Inc. Site, Toledo, Ohio Manager, DOE Oak Ridge Field Office This is to notify you that the Former Baker Brothers, Inc. site...

170

Cell, Vol. 29, 551-559, June 1982, Copyright 0 1982 by MIT Directed Transposon Tn5 Mutagenesis and  

E-Print Network (OSTI)

(nif) was cloned from the genome of the symbiotic nitrogen-fixing species Rhizobium meliloti. A total of 31 Tn5 insertions in the nif region were constructed and assayed for their effect on symbiotic between genomic nif: :TnS insertions and nif: :Tn5 insertions on mo- bilizable cloning vectors

Ausubel, Frederick M.

171

Synchrotron Radiation Photoemission Spectroscopic Study of Band Offsets and Interface Self-cleaning by Atomic Layer Deposited HfO2 on In0.53Ga0.47As and In0.52Al0.48As  

SciTech Connect

The Synchrotron Radiation Photoemission Spectroscopic (SRPES) study was conducted to (a) investigate the surface chemistry of In{sub 0.53}Ga{sub 0.47}As and In{sub 0.52}Al{sub 0.48}As post chemical and thermal treatments, (b) construct band diagram and (c) investigate the interface property of HfO{sub 2}/In{sub 0.53}Ga{sub 0.47}As and HfO{sub 2}/In{sub 0.52}Al{sub 0.48}As. Dilute HCl and HF etch remove native oxides on In{sub 0.53}Ga{sub 0.47}As and In{sub 0.52}Al{sub 0.47}As, whereas in-situ vacuum annealing removes surface arsenic pile-up. After the atomic layer deposition of HfO{sub 2}, native oxides were considerably reduced compared to that in as-received epi-layers, strongly suggesting the self-clean mechanism. Valence and conduction band offsets are measured to be 3.37 {+-} 0.1eV, 1.80 {+-} 0.3eV for In{sub 0.53}Ga{sub 0.47}As and 3.00 {+-} 0.1eV, 1.47 {+-} 0.3eV for In{sub 0.52}Al{sub 0.47}As, respectively.

Kobayashi, Masaharu; /SLAC, SSRL; Chen, P.T.; Sun, Y.; Goel, N.; Majhi, P.; Garner, M; Tsai, W.; Pianetta, P.; Nishi, Y.; /SLAC, SSRL

2008-10-31T23:59:59.000Z

172

Synthesis and structural characterization of the ternary Zintl phases AE{sub 3}Al{sub 2}Pn{sub 4} and AE{sub 3}Ga{sub 2}Pn{sub 4} (AE=Ca, Sr, Ba, Eu; Pn=P, As)  

Science Conference Proceedings (OSTI)

Ten new ternary phosphides and arsenides with empirical formulae AE{sub 3}Al{sub 2}Pn{sub 4} and AE{sub 3}Ga{sub 2}Pn{sub 4} (AE=Ca, Sr, Ba, Eu; Pn=P, As) have been synthesized using molten Ga, Al, and Pb fluxes. They have been structurally characterized by single-crystal and powder X-ray diffraction to form with two different structures-Ca{sub 3}Al{sub 2}P{sub 4}, Sr{sub 3}Al{sub 2}As{sub 4}, Eu{sub 3}Al{sub 2}P{sub 4}, Eu{sub 3}Al{sub 2}As{sub 4}, Ca{sub 3}Ga{sub 2}P{sub 4}, Sr{sub 3}Ga{sub 2}P{sub 4}, Sr{sub 3}Ga{sub 2}As{sub 4}, and Eu{sub 3}Ga{sub 2}As{sub 4} crystallize with the Ca{sub 3}Al{sub 2}As{sub 4} structure type (space group C2/c, Z=4); Ba{sub 3}Al{sub 2}P{sub 4} and Ba{sub 3}Al{sub 2}As{sub 4} adopt the Na{sub 3}Fe{sub 2}S{sub 4} structure type (space group Pnma, Z=4). The polyanions in both structures are made up of TrPn{sub 4} tetrahedra, which share common corners and edges to form {sup 2}{sub {infinity}}[TrPn{sub 2}]{sub 3-} layers in the phases with the Ca{sub 3}Al{sub 2}As{sub 4} structure, and {sup 1}{sub {infinity}}[TrPn{sub 2}]{sub 3-} chains in Ba{sub 3}Al{sub 2}P{sub 4} and Ba{sub 3}Al{sub 2}As{sub 4} with the Na{sub 3}Fe{sub 2}S{sub 4} structure type. The valence electron count for all of these compounds follows the Zintl-Klemm rules. Electronic band structure calculations confirm them to be semiconductors. - Graphical abstract: AE{sub 3}Al{sub 2}Pn{sub 4} and AE{sub 3}Ga{sub 2}Pn{sub 4} (AE=Ca, Sr, Ba, Eu; Pn=P, As) crystallize in two different structures-Ca{sub 3}Al{sub 2}P{sub 4}, Sr{sub 3}Al{sub 2}As{sub 4}, Eu{sub 3}Al{sub 2}P{sub 4}, Eu{sub 3}Al{sub 2}As{sub 4}, Ca{sub 3}Ga{sub 2}P{sub 4}, Sr{sub 3}Ga{sub 2}P{sub 4}, Sr{sub 3}Ga{sub 2}As{sub 4}, and Eu{sub 3}Ga{sub 2}As{sub 4}, are isotypic with the previously reported Ca{sub 3}Al{sub 2}As{sub 4} (space group C2/c (No. 15)), while Ba{sub 3}Al{sub 2}P{sub 4} and Ba{sub 3}Al{sub 2}As{sub 4} adopt a different structure known for Na{sub 3}Fe{sub 2}S{sub 4} (space group Pnma (No. 62). The polyanions in both structures are made up of TrPn{sub 4} tetrahedra, which by sharing common corners and edges, form {sup 2}{sub {infinity}}[TrPn{sub 2}]{sub 3-}layers in the former and {sup 1}{sub {infinity}}[TrPn{sub 2}]{sub 3-} chains in Ba{sub 3}Al{sub 2}P{sub 4} and Ba{sub 3}Al{sub 2}As{sub 4}. Highlights: Black-Right-Pointing-Pointer AE{sub 3}Ga{sub 2}Pn{sub 4} (AE=Ca, Sr, Ba, Eu; Pn=P, As) are new ternary pnictides. Black-Right-Pointing-Pointer Ba{sub 3}Al{sub 2}P{sub 4} and Ba{sub 3}Al{sub 2}As{sub 4} adopt the Na{sub 3}Fe{sub 2}S{sub 4} structure type. Black-Right-Pointing-Pointer The Sr- and Ca-compounds crystallize with the Ca{sub 3}Al{sub 2}As{sub 4} structure type. Black-Right-Pointing-Pointer The valence electron count for all title compounds follows the Zintl-Klemm rules.

He, Hua; Tyson, Chauntae; Saito, Maia [Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716 (United States); Bobev, Svilen, E-mail: bobev@udel.edu [Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716 (United States)

2012-04-15T23:59:59.000Z

173

HH8, Characterization of Thin InAlP Native Oxide Gate Dielectric ...  

Science Conference Proceedings (OSTI)

DD3, A New Approach to Make ZnO-Cu2O Heterojunctions for Solar Cells ... E2, AlGaAs/GaAs/GaN Wafer Fused HBTs with Ar Implanted Extrinsic Collectors.

174

BB2, Novel Cs-Free GaN Photocathodes  

Science Conference Proceedings (OSTI)

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

175

Simulation and Design Analysis of (A1Ga)As/GaAs MODFET Integrated Circuits  

Science Conference Proceedings (OSTI)

A new (AlGa)As/GaAs MODFET integrated circuit simulator is described. Our simulator is a customized version of SPICE incorporating the extended charge control model for MODFET's and the velocity saturation model for ungated FET's used as the load devices. ...

Choong H. Hyun; M. S. Shur; N. C. Cirillo

2006-11-01T23:59:59.000Z

176

DOE - Office of Legacy Management -- W R Grace - Erwin - TN 05  

Office of Legacy Management (LM)

- Erwin - TN 05 - Erwin - TN 05 FUSRAP Considered Sites Site: W R Grace - Erwin (TN.05) Designated Name: Alternate Name: Location: Evaluation Year: Site Operations: Site Disposition: Radioactive Materials Handled: Primary Radioactive Materials Handled: Radiological Survey(s): Site Status: This site is one of a group of 5 FUSRAP considered sites for which records are available that provide a reasonably complete historical account of their operations and relationship, if any, with MED/AEC operations. However, additional analyses of these historical records, and more recent documentation of decisions concerning the authority and other considerations related to the elimination of these sites from further consideration under FUSRAP is warranted. These analyses will provide the

177

Summary - Mitigation and Remediation of Mercury Contamination at the Y-12 Plant, Oak Ridge, TN  

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

Oak Ridge, TN Oak Ridge, TN EM Project: Mitigation/Remediation of Hg ETR Report Date: April 2008 ETR-13 United States Department of Energy Office of Environmental Management (DOE-EM) External Technical Review of the Mitigation and Remediation of Mercury Contamination at the Y-12 Plant, Oak Ridge, TN Why DOE-EM Did This Review From 1953 to 1983, ~240,000 pounds of mercury (Hg) were released to the East Fork Popular Creek during the operation of the Y-12 Plant. In 1963, direct systematic releases of mercury stopped; however, mercury continues to be released into the creek from various sources of contamination in the Y-12 complex. Remediation completed up to 1992 resulted in an overall reduction of Hg loading from 150 g/day in 1983 to 15 g/day in 1992, with a

178

DOE - Office of Legacy Management -- Union Carbide and Carbon Co - TN 10  

Office of Legacy Management (LM)

Carbide and Carbon Co - TN 10 Carbide and Carbon Co - TN 10 FUSRAP Considered Sites Site: Union Carbide and Carbon Co (TN.10) Designated Name: Alternate Name: Location: Evaluation Year: Site Operations: Site Disposition: Radioactive Materials Handled: Primary Radioactive Materials Handled: Radiological Survey(s): Site Status: This site is one of a group of 5 FUSRAP considered sites for which records are available that provide a reasonably complete historical account of their operations and relationship, if any, with MED/AEC operations. However, additional analyses of these historical records, and more recent documentation of decisions concerning the authority and other considerations related to the elimination of these sites from further consideration under FUSRAP is warranted. These analyses will provide the

179

Summary - Environmental Management Waste Management Facility (EMWMF) at Oak Ridge, TN  

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

Oak Ridge, TN Oak Ridge, TN EM Project: EM Waste Management Facility ETR Report Date: February 2008 ETR-11 United States Department of Energy Office of Environmental Management (DOE-EM) External Technical Review of Environmental Management Waste Management Facility (EMWMF) at Oak Ridge, TN Why DOE-EM Did This Review The Environmental Management Waste Management Facility (EMWMF) is a land disposal facility for wastes generated by environmental restoration activities being conducted at the US Department of Energy's (DOE) Oak Ridge Reservation. Low-level radioactive wastes, hazardous wastes (Subtitle C of the Resource Conservation and Recovery Act), and wastes defined by the Toxic Substances Control Act are approved for disposal in the EMWMF. All of the cells are lined with a

180

3D-Orientation Space; Filters and Sampling Frank G.A. Faas and Lucas J. van Vliet  

E-Print Network (OSTI)

3D-Orientation Space; Filters and Sampling Frank G.A. Faas and Lucas J. van Vliet Pattern,lucas}@ph.tn.tudelft.nl Abstract. The orientation space transform is a concept that can deal with multiple oriented structures at a single location. In this paper we extend the orientation space transform to 3D images producing a 5D

van Vliet, Lucas J.

Note: This page contains sample records for the topic "tn al ga" 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

Electric field engineering in GaN high electron mobility transistors  

E-Print Network (OSTI)

In the last few years, AlGaN/GaN high electron mobility transistors (HEMTs) have become the top choice for power amplification at frequencies up to 20 GHz. Great interest currently exists in industry and academia to increase ...

Zhao, Xu, S.M. Massachusetts Institute of Technology

2008-01-01T23:59:59.000Z

182

lntersubbancl transitions in high indium content InGaAs/AIGaAs quantum wells  

E-Print Network (OSTI)

lntersubbancl transitions in high indium content InGaAs/AIGaAs quantum wells H. C. Chui, S. M. Lord report the first observation of intersubband transitions in In,Ga, -#s(y=O.3,0.5)/ AlGaAs quantum wells. These quantum wells were grown on a GaAs substrate with a linearly graded InGaAs buffer to achieve strain

Fejer, Martin M.

183

NIL PHENOMENA IN TOPOLOGY (1415 APRIL 2007) VANDERBILT UNIVERSITY (NASHVILLE, TN U.S.A.)  

E-Print Network (OSTI)

. Consider the cartesian square Z[G] // Z[G]/ // /n. 1 #12;2 B. HUGHES, Q. KHAN (ORGANIZERS); I. HAMBLETONNIL PHENOMENA IN TOPOLOGY (14­15 APRIL 2007) VANDERBILT UNIVERSITY (NASHVILLE, TN U.S.A.) PROBLEM SESSION BRUCE HUGHES, QAYUM KHAN (ORGANIZERS) IAN HAMBLETON (MODERATOR) IO. (Ivonne Ortiz, Miami of Ohio

Hughes, Bruce

184

EA-1514: Proposed Conveyance of Parcel ED-6 to the City of Oak Ridge, TN  

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

This Environmental Assessment was prepared for the conveyance of approximately 336 acres of excess property (i.e., property not needed to fulfill DOE current or foreseeable future requirements) known as Parcel ED-6 to the city of Oak Ridge, TN.

185

Lattice-matched epitaxial GaInAsSb/GaSb thermophotovoltaic devices  

DOE Green Energy (OSTI)

The materials development of Ga{sub 1{minus}x}In{sub x}As{sub y}Sb{sub 1{minus}y} alloys for lattice-matched thermophotovoltaic (TPV) devices is reported. Epilayers with cutoff wavelength 2--2.4 {micro}m at room temperature and lattice-matched to GaSb substrates were grown by both low-pressure organometallic vapor phase epitaxy and molecular beam epitaxy. These layers exhibit high optical and structural quality. For demonstrating lattice-matched thermophotovoltaic devices, p- and n-type doping studies were performed. Several TPV device structures were investigated, with variations in the base/emitter thicknesses and the incorporation of a high bandgap GaSb or AlGaAsSb window layer. Significant improvement in the external quantum efficiency is observed for devices with an AlGaAsSb window layer compared to those without one.

Wang, C.A.; Choi, H.K.; Turner, G.W.; Spears, D.L.; Manfra, M.J. [Massachusetts Inst. of Tech., Lexington, MA (United States). Lincoln Lab.; Charache, G.W. [Lockheed Martin, Inc., Schenectady, NY (United States)

1997-05-01T23:59:59.000Z

186

, 2004, 46, . 1 GaAs/AlGaAs  

E-Print Network (OSTI)

, S. Rumyantsev, J.-Q. L¨u, M.S. Shur, C.A. Saylor, L.C. Brunel. Appl. Phys. Lett. 80, 18, 3433 (2002. L¨u, R. Gaska, M.S. Shur, F. Simin, X. Hu, M. Asif Khan, C.A. Saylor, L.C. Brunel. J. Appl. Phys. 91, , N. Dyakonova , E. Kaminska , A. Piotrowska , K. Golaszewska , M.S. Shur , 603950 , GES

Levelut, Claire

187

Properties of double-layered Ga-doped Al-zinc-oxide/titanium-doped indium-tin-oxide thin films prepared by dc magnetron sputtering applied for Si-based thin film solar cells  

Science Conference Proceedings (OSTI)

In this article, Ga-doped Al-zinc-oxide (GAZO)/titanium-doped indium-tin-oxide (ITIO) bi-layer films were deposited onto glass substrates by direct current (dc) magnetron sputtering. The bottom ITIO film, with a thickness of 200 nm, was sputtered onto the glass substrate. The ITIO film was post-annealed at 350 deg. C for 10-120 min as a seed layer. The effect of post-annealing conditions on the morphologies, electrical, and optical properties of ITIO films was investigated. A GAZO layer with a thickness of 1200 nm was continuously sputtered onto the ITIO bottom layer. The results show that the properties of the GAZO/ITIO films were strongly dependent on the post-annealed conditions. The spectral haze (T{sub diffuse}/T{sub total}) of the GAZO/ITIO bi-layer films increases upon increasing the post-annealing time. The haze and resistivity of the GAZO/ITIO bi-layer films were improved with the post-annealed process. After optimizing the deposition and annealing parameters, the GAZO/ITIO bi-layer film has an average transmittance of 83.20% at the 400-800 nm wavelengths, a maximum haze of 16%, and the lowest resistivity of 1.04 x 10{sup -3}{Omega} cm. Finally, the GAZO/ITIO bi-layer films, as a front electrode for silicon-based thin film solar cells, obtained a maximum efficiency of 7.10%. These encouraging experimental results have potential applications in GAZO/ITIO bi-layer film deposition by in-line sputtering without the wet-etching process and enable the production of highly efficient, low-cost thin film solar cells.

Wang, Chao-Chun; Wuu, Dong-Sing; Lin, Yang-Shih; Lien, Shui-Yang; Huang, Yung-Chuan; Liu, Chueh-Yang; Chen, Chia-Fu; Nautiyal, Asheesh; Lee, Shuo-Jen [Department of Materials Science and Engineering, National Chung Hsing University, Taichung 40227, Taiwan (China); Department of Materials Science and Engineering, MingDao University, Changhua 52345, Taiwan (China); Department of Mechanical Engineering, Yuan Ze University, Taoyuan 320, Taiwan (China)

2011-11-15T23:59:59.000Z

188

China Ga Air Compressor, China Ga Air Compressor Products ...  

U.S. Energy Information Administration (EIA)

China Ga Air Compressor, China Ga Air Compressor Suppliers and Manufacturers Directory - Source a Large Selection of Ga Air Compressor Products at ...

189

File:USDA-CE-Production-GIFmaps-TN.pdf | Open Energy Information  

Open Energy Info (EERE)

TN.pdf TN.pdf Jump to: navigation, search File File history File usage Tennessee Ethanol Plant Locations Size of this preview: 776 × 600 pixels. Full resolution ‎(1,650 × 1,275 pixels, file size: 332 KB, MIME type: application/pdf) Description Tennessee Ethanol Plant Locations Sources United States Department of Agriculture Related Technologies Biomass, Biofuels, Ethanol Creation Date 2010-01-19 Extent State Countries United States UN Region Northern America States Tennessee External links http://www.nass.usda.gov/Charts_and_Maps/Ethanol_Plants/ File history Click on a date/time to view the file as it appeared at that time. Date/Time Thumbnail Dimensions User Comment current 16:21, 27 December 2010 Thumbnail for version as of 16:21, 27 December 2010 1,650 × 1,275 (332 KB) MapBot (Talk | contribs) Automated bot upload

190

File:EIA-Appalach7-TN-KY-LIQ.pdf | Open Energy Information  

Open Energy Info (EERE)

Appalach7-TN-KY-LIQ.pdf Appalach7-TN-KY-LIQ.pdf Jump to: navigation, search File File history File usage Appalachian Basin, Kentucky and Tennessee By 2001 Liquids Reserve Class Size of this preview: 463 × 599 pixels. Other resolution: 464 × 600 pixels. Full resolution ‎(5,100 × 6,600 pixels, file size: 19.31 MB, MIME type: application/pdf) Description Appalachian Basin, Kentucky and Tennessee By 2001 Liquids Reserve Class Sources Energy Information Administration Authors Samuel H. Limerick; Lucy Luo; Gary Long; David F. Morehouse; Jack Perrin; Robert F. King Related Technologies Oil, Natural Gas Creation Date 2005-09-01 Extent Regional Countries United States UN Region Northern America States Kentucky, Tennessee File history Click on a date/time to view the file as it appeared at that time.

191

InGaAs and Ge MOSFETs with high ? dielectrics  

Science Conference Proceedings (OSTI)

InGaAs and Ge MOSFETs with high @k's are now the leading candidates for technology beyond the 15nm node CMOS. The UHV-Al"2O"3/Ga"2O"3(Gd"2O"3) [GGO]/InGaAs has low electrical leakage current densities, C-V characteristics with low interfacial densities ... Keywords: Atomic layer deposition, Germanium, High ? dielectrics, III-V Compound semiconductor, MOSFETs, Molecular beam epitaxy

W. C. Lee; P. Chang; T. D. Lin; L. K. Chu; H. C. Chiu; J. Kwo; M. Hong

2011-04-01T23:59:59.000Z

192

X=Bi, Sb, Al, Ga  

Science Conference Proceedings (OSTI)

... Nd-Fe-B Permanent Magnets · Unique Exchange Bias Induced by Antiferromagnetic Cr-oxide · ZnO-graphene Hybrid Quantum Dots Light Emitting Diode ...

193

Seamless On-Wafer Integration of Si(100) MOSFETs and GaN HEMTs  

E-Print Network (OSTI)

The first on-wafer integration of Si(100) MOSFETs and AlGaN/GaN high electron mobility transistors (HEMTs) is demonstrated. To enable a fully Si-compatible process, we fabricated a novel Si(100)-GaN-Si(100) virtual substrate ...

Piner, Edwin L.

194

In situ atomic layer deposition and synchrotron-radiation photoemission study of Al2O3 on pristine n-GaAs(0 0 1)-4×6 surface  

Science Conference Proceedings (OSTI)

This work presents the in situ reflection high-energy electron diffraction (RHEED), scanning tunneling microscopy (STM) and synchrotron-radiation photoemission studies for the morphological and interfacial chemical characterization of in situ atomic ... Keywords: Atomic layer deposition, GaAs, Molecular beam epitaxy, Synchrotron-radiation photoemission

Y. H. Chang; M. L. Huang; P. Chang; J. Y. Shen; B. R. Chen; C. L. Hsu; T. W. Pi; M. Hong; J. Kwo

2011-07-01T23:59:59.000Z

195

The Sugar Creek zinc deposit, Jackson Co. TN -- Exploration history, geology and mineralization  

SciTech Connect

During the 60's and 70's zinc exploration of central TN and KY was active. The Sugar Creek Project was one of several investigated by Exxon. The discovery hole, Cu 15, was drilled in early 1973. The Sugar Creek Zinc Deposit was acquired by Independence Mining Co. in 1986 and I.M.C. has subsequently completed additional drilling, both stepout and confirmation holes. A total of 137 holes for 300,833 ft have been drilled. The Sugar Creek deposit is a typical Tennessee zinc deposit (Mississippi Valley Type) which occurs in solution collapse breccias in the Lower Ordovician, Knox Dolomite. The Knox consists of fine grained dolomite with interlayered limestones and crystalline dolomite. Only scattered residual limestone is found in the Sugar Creek area. Collapse breccias have formed which control zinc deposition and are similar to other TN Zn. deposits. At Sugar Creek the types of breccias include: a vertically exaggerated glory hole breakthrough breccia which extends to within 137 ft. of the Knox unconformity, has 500 ft. of zinc mineralization with 8 significant zinc intervals; holes with stacked zinc intervals interpreted to be sides of breakthrough breccia; and single zinc intervals in laterally positioned bedded mineral zones. A total of 99 holes were drilled in the more intense mineralized areas. The ratio of ore to non ore holes is nearly 1 to 1. The mineralization is typical M.V.T. with predominantly sphalerite and only minor occurrences of galena, fluorite, pyrite, etc.

Reinbold, G.; Moran, A.V.; Stevens, D.L. (Independence Mining Co. Inc., Reno, NV (United States))

1993-03-01T23:59:59.000Z

196

Dielectrics for GaN based MIS-diodes  

SciTech Connect

GaN MIS diodes were demonstrated utilizing AlN and Ga{sub 2}O{sub 3}(Gd{sub 2}O{sub 3}) as insulators. A 345 {angstrom} of AlN was grown on the MOCVD grown n-GaN in a MOMBE system using trimethylamine alane as Al precursor and nitrogen generated from a wavemat ECR N2 plasma. For the Ga{sub 2}O{sub 3}(Gd{sub 2}O{sub 3}) growth, a multi MBE chamber was used and a 195 {angstrom} oxide is E-beam evaporated from a single crystal source of Ga{sub 5}Gd{sub 3}O{sub 12}. The forward breakdown voltage of AlN and Ga{sub 2}O{sub 3}(Gd{sub 2}O{sub 3}) diodes are 5V and 6V, respectively, which are significantly improved from {approximately} 1.2 V of schottky contact. From the C-V measurements, both kinds of diodes showed good charge modulation from accumulation to depletion at different frequencies. The insulator GaN interface roughness and the thickness of the insulator were measured with x-ray reflectivity.

Ren, F.; Abernathy, C.R.; MacKenzie, J.D. [Univ. of Florida, Gainesville, FL (United States)] [and others

1998-02-01T23:59:59.000Z

197

JJ3, Anisotropic Carrier Mobility in GaN Quantum Well  

Science Conference Proceedings (OSTI)

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

198

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 [

199

Y5, Electrochemical Etching of GaN and Its Applications  

Science Conference Proceedings (OSTI)

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

200

Collapse for Higher Gate Voltages in N-Polar GaN  

Science Conference Proceedings (OSTI)

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

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Note: This page contains sample records for the topic "tn al ga" 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.


Index
201

N7, Olefin Metathesis Reaction on GaN (0001) Surfaces  

Science Conference Proceedings (OSTI)

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

202

Linear Collider Collaboration Tech Notes LCC-0140 SLAC-TN-04-041  

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

0 0 SLAC-TN-04-041 June 2004 Abstract This note documents a set of expressions used to explore the issue of whether or not it is reasonable to consider a conventional positron source for a Tesla formatted beam. The critical issue is that of energy deposition in the conversion target and the comparison of the induced stress with the ultimate tensile strength of the target material. Since the length of the incident beam pulse is large in comparison to the ratio of beam size to the speed of sound, the concurrent pressure pulse dissipates in a time short compared to the overall pulse duration and one is left with only the Sensitivity to Nano-Tesla Scale Stray Magnetic Fields J. Frisch, T.O. Raubenheimer, P. Tenenbaum

203

Linear Collider Collaboration Tech Notes LCC-0139 SLAC-TN-04-042  

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

9 9 SLAC-TN-04-042 May 2004 Abstract This note documents a set of expressions used to explore the issue of whether or not it is reasonable to consider a conventional positron source for a Tesla formatted beam. The critical issue is that of energy deposition in the conversion target and the comparison of the induced stress with the ultimate tensile strength of the target material. Since the length of the incident beam pulse is large in comparison to the ratio of beam size to the speed of sound, the concurrent pressure pulse dissipates in a time short compared to the overall pulse duration and one is left with only the Alternative Main Linac BNS Configurations for Reduced Energy Spread Andrei Seryi and Peter Tenenbaum

204

Linear Collider Collaboration Tech Notes LCC-0141 SLAC-TN-04-040  

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

1 1 SLAC-TN-04-040 May 2004 Abstract This note documents a set of expressions used to explore the issue of whether or not it is reasonable to consider a conventional positron source for a Tesla formatted beam. The critical issue is that of energy deposition in the conversion target and the comparison of the induced stress with the ultimate tensile strength of the target material. Since the length of the incident beam pulse is large in comparison to the ratio of beam size to the speed of sound, the concurrent pressure pulse dissipates in a time short compared to the overall pulse duration and one is left with only the Availability and Failure Effects of NLC Main Linac Mechanical Movers T. M. Himel, C. Spencer, Peter Tenenbaum

205

TN-68 Spent Fuel Transport Cask Analytical Evaluation for Drop Events  

SciTech Connect

The U.S. Nuclear Regulatory Commission (NRC) is responsible for licensing commercial spent nuclear fuel transported in casks certified by NRC under the Code of Federal Regulations (10 CFR), Title 10, Part 71 [1]. Both the International Atomic Energy Agency regulations for transporting radioactive materials [2, paragraph 727], and 10 CFR 71.73 require casks to be evaluated for hypothetical accident conditions, which includes a 9-meter (m) (30-ft) drop-impact event onto a flat, essentially unyielding, horizontal surface, in the most damaging orientation. This paper examines the behavior of one of the NRC certified transportation casks, the TN-68 [3], for drop-impact events. The specific area examined is the behavior of the bolted connections in the cask body and the closure lid, which are significantly loaded during the hypothetical drop-impact event. Analytical work to evaluate the NRC-certified TN-68 spent fuel transport cask [3] for a 9-m (30-ft) drop-impact event on a flat, unyielding, horizontal surface, was performed using the ANSYS® [4] and LS DYNA™ [5] finite-element analysis codes. The models were sufficiently detailed, in the areas of bolt closure interfaces and containment boundaries, to evaluate the structural integrity of the bolted connections under 9-m (30-ft) free-drop hypothetical accident conditions, as specified in 10 CFR 71.73. Evaluation of the cask for puncture, caused by a free drop through a distance of 1-m (40-in.) onto a mild steel bar mounted on a flat, essentially unyielding, horizontal surface, required by 10 CFR 71.73, was not included in the current work, and will have to be addressed in the future. Based on the analyses performed to date, it is concluded that, even though brief separation of the flange and the lid surfaces may occur under some conditions, the seals would close at the end of the drop events, because the materials remain elastic during the duration of the event.

Shah, M. J.; Klymyshyn, Nicholas A.; Adkins, Harold E.; Koeppel, Brian J.

2007-03-30T23:59:59.000Z

206

Micro-Photoluminescence Characterization of Low Density Droplet GaAs Quantum Dots for Single Photon Sources  

Science Conference Proceedings (OSTI)

The GaAs quantum dots in AlGaAs barriers were grown by droplet epitaxy, emitting around 700 nm in wavelength which is compatible with low cost Si based detectors. The excitation power dependent and time resolved micro-photoluminescence measurements identified optical characteristics of exciton and biexciton states which are attributed to good quantum confinements in GaAs QDs.

Ha, S.-K.; Song, J. D.; Lim, J. Y.; Choi, W. J.; Han, I. K.; Lee, J. I. [Nano Convergence Devices Center, KIST, Seoul 136-791 (Korea, Republic of); Bounouar, S.; Donatini, F.; Dang, L. S.; Poizat, J. P. [CEA/CNRS/UJF team 'Nanophysics and semiconductors', Institute Neel/CNRS-UJF, 38042 Grenoble (France); Kim, J. S. [Department of Physics, Yeungnam University, Gyeongsan 712-749 (Korea, Republic of)

2011-12-23T23:59:59.000Z

207

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...

208

Al-Cr -2007-1 February 1, 2007 Aluminum and Chromium Leaching ...  

Al-Cr -2007-1 February 1, 2007 Aluminum and Chromium Leaching Workshop Atlanta, GA January 23 – 24, 2007 Crowne Plaza – Airport Feedback Questionnaire

209

Ultra High p-doping Material Research for GaN Based Light Emitters  

Science Conference Proceedings (OSTI)

The main goal of the Project is to investigate doping mechanisms in p-type GaN and AlGaN and controllably fabricate ultra high doped p-GaN materials and epitaxial structures. Highly doped p-type GaN-based materials with low electrical resistivity and abrupt doping profiles are of great importance for efficient light emitters for solid state lighting (SSL) applications. Cost-effective hydride vapor phase epitaxial (HVPE) technology was proposed to investigate and develop p-GaN materials for SSL. High p-type doping is required to improve (i) carrier injection efficiency in light emitting p-n junctions that will result in increasing of light emitting efficiency, (ii) current spreading in light emitting structures that will improve external quantum efficiency, and (iii) parameters of Ohmic contacts to reduce operating voltage and tolerate higher forward currents needed for the high output power operation of light emitters. Highly doped p-type GaN layers and AlGaN/GaN heterostructures with low electrical resistivity will lead to novel device and contact metallization designs for high-power high efficiency GaN-based light emitters. Overall, highly doped p-GaN is a key element to develop light emitting devices for the DOE SSL program. The project was focused on material research for highly doped p-type GaN materials and device structures for applications in high performance light emitters for general illumination P-GaN and p-AlGaN layers and multi-layer structures were grown by HVPE and investigated in terms of surface morphology and structure, doping concentrations and profiles, optical, electrical, and structural properties. Tasks of the project were successfully accomplished. Highly doped GaN materials with p-type conductivity were fabricated. As-grown GaN layers had concentration N{sub a}-N{sub d} as high as 3 x 10{sup 19} cm{sup -3}. Mechanisms of doping were investigated and results of material studies were reported at several International conferences providing better understanding of p-type GaN formation for Solid State Lighting community. Grown p-type GaN layers were used as substrates for blue and green InGaN-based LEDs made by HVPE technology at TDI. These results proved proposed technical approach and facilitate fabrication of highly conductive p-GaN materials by low-cost HVPE technology for solid state lighting applications. TDI has started the commercialization of p-GaN epitaxial materials.

Vladimir Dmitriev

2007-06-30T23:59:59.000Z

210

Analysis of mechanisms of carrier emission in the p-i-n structures with In(Ga)As quantum dots  

SciTech Connect

With the help of the photocurrent spectroscopy, the mechanism of emission of charge carriers from energy levels of the (In,Ga)As/(Al,Ga)As quantum dots of different design are studied. Thermal activation is shown to be the main mechanism of carrier emission from the quantum dots for the isolated layer of quantum dots separated by wide (Al,Ga)As spacer layers. At a small width of the (Al,Ga)As spacer layer, when electron binding of separate layers of the quantum dots in the vertical direction takes place, the role of the tunneling mechanism of carrier emission between the vertically coupled quantum dots increases.

Shatalina, E. S., E-mail: Shatalina@mail.ioffe.ru; Blokhin, S. A.; Nadtochy, A. M.; Payusov, A. S.; Savelyev, A. V.; Maximov, M. V.; Zhukov, A. E. [St. Petersburg Academic University, Nanotechnology Research and Education Centre (Russian Federation); Ledentsov, N. N. [Russian Academy of Sciences, Ioffe Physical Technical Institute (Russian Federation); Kovsh, A. R.; Mikhrin, S. S.; Ustinov, V. M. [Innolume GmbH (Germany)

2010-10-15T23:59:59.000Z

211

Growth and development of GaInAsP for use in high-efficiency solar cells  

DOE Green Energy (OSTI)

This report describes work done during Phase II of the subcontract. Goals for Phase II include the following: (1) Optimize the GaInAsP cell on GaAs and demonstrate a 500-sun at air mass (AM) 1.5 efficiency of >23%. (2) Develop a window layer, including the evaluation of AlGaAs, GaInP, AlGaAsP, AlGaInP, and GaP. (3) Develop a front-surface contact, with a grid designed for 500-sun concentration, and a goal of a contact resistivity of [approximately]10[sup 5] ohm-cm[sup 2]. (4) Grow GaInAsP cells on Ge, with a goal of a 1-sun (AM 1.5) efficiency of >15%. Accomplishments reported herein include (1) the fabrication of p-on-n and n-on-p GaInAsP cells on GaAs, with the n-on-p cell demonstrating a 10-sun (AM 1.5) active-area efficiency of 23.4% as measured at NREL (2) the evaluation of Al[sub x]Ga([sub 1-x])As, GaInP[sub 2], and AlInP[sub 2] window layers; and (3) the fabrication of GaInAsP cells on Ge, with the demonstration of a p-on-n GaInAsP cell grown on Ge with a 1-sun (AM 1.5) active-area efficiency of 14.4%.

Sharps, P.R. (Research Triangle Inst., Research Triangle Park, NC (United States))

1993-04-01T23:59:59.000Z

212

The Effect of Periodic Silane Burst on the Properties of GaN on Si (111) Substrates  

E-Print Network (OSTI)

The periodic silane burst technique was employed during metalorganic chemical vapor deposition of epitaxial GaN on AlN buffer layers grown on Si (111). Periodic silicon delta doping during growth of both the AlN and GaN ...

Zang, Keyan

213

Explosive Demolition of a Fire-Water Tower At East Tennessee Technology Park, Oak Ridge TN  

SciTech Connect

On June 17, 2006, the Department of Energy (DOE) successfully demolished a {approx}60 year old fire-water tower (K-1206-E), located at the East Tennessee Technology Park (ETTP) in Oak Ridge, TN, using strategically placed explosive charges. The subject demolition project was executed by MCM Management Corporation and Demolition Dynamics under the management of DoE's prime contractor Bechtel Jacobs Company LLC (BJC). The K-1206-E Fire Water Tower (Tower) supported the ETTP fire water protection system from the mid- 1950's until 1991. The 378,500-L (100,000-gallon) Tower, elevated 53-m (175-feet) above grade, was located in a grassy area within 152-m (500-feet) of several other occupied facilities. Electrical, control circuits and supply water servicing the Tower were deactivated in 2003. Free liquids and sludge were removed from the tank prior to demolition. Demolition of a facility employing explosive demolition at a federal site in the 'post-9/11 era' was a substantial challenge. The subject paper discusses: - the planning and coordination steps that were taken to successfully overcome the challenges prior to the demolition of the empty, deactivated Tower; - the method used for the engineered demolition of the Tower; and - the factors responsible for the successful execution of this demolition project. At least two previous attempts were made to demolish the Tower. In the first attempt, the execution of the project was deferred by the re-allocation of funds. In the subsequent attempt in 2004, the execution of this project was postponed due to concerns that an adjacent facility would have to shut down operations during the duration of mobilization and execution of the project and thereby incur potential financial losses. A total of 51 cubic meters (1,800 cubic feet) of demolition debris was generated, which was compliantly disposed of at a local landfill followed by site restoration.

Brooksbank, R.D.; Rood, M.S.; Amrit, S.K.; Harper, M.S.; Dypolt, D.J.; Brehse, Mike [Bechtel Jacobs Company LLC, P.O. Box 4699 Oak Ridge, TN 37931 (United States)

2008-01-15T23:59:59.000Z

214

ALS Spectrum  

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

ALS Spectrum Print Begun in 2007, ALS Spectrum is a publication that encapsulates the same type of information contained in the ALS Activity Report but in a short, readable,...

215

ALS Spectrum  

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

Spectrum Print Begun in 2007, ALS Spectrum is a publication that encapsulates the same type of information contained in the ALS Activity Report but in a short, readable,...

216

Materials physics and device development for improved efficiency of GaN HEMT high power amplifiers.  

SciTech Connect

GaN-based microwave power amplifiers have been identified as critical components in Sandia's next generation micro-Synthetic-Aperture-Radar (SAR) operating at X-band and Ku-band (10-18 GHz). To miniaturize SAR, GaN-based amplifiers are necessary to replace bulky traveling wave tubes. Specifically, for micro-SAR development, highly reliable GaN high electron mobility transistors (HEMTs), which have delivered a factor of 10 times improvement in power performance compared to GaAs, need to be developed. Despite the great promise of GaN HEMTs, problems associated with nitride materials growth currently limit gain, linearity, power-added-efficiency, reproducibility, and reliability. These material quality issues are primarily due to heteroepitaxial growth of GaN on lattice mismatched substrates. Because SiC provides the best lattice match and thermal conductivity, SiC is currently the substrate of choice for GaN-based microwave amplifiers. Obviously for GaN-based HEMTs to fully realize their tremendous promise, several challenges related to GaN heteroepitaxy on SiC must be solved. For this LDRD, we conducted a concerted effort to resolve materials issues through in-depth research on GaN/AlGaN growth on SiC. Repeatable growth processes were developed which enabled basic studies of these device layers as well as full fabrication of microwave amplifiers. Detailed studies of the GaN and AlGaN growth of SiC were conducted and techniques to measure the structural and electrical properties of the layers were developed. Problems that limit device performance were investigated, including electron traps, dislocations, the quality of semi-insulating GaN, the GaN/AlGaN interface roughness, and surface pinning of the AlGaN gate. Surface charge was reduced by developing silicon nitride passivation. Constant feedback between material properties, physical understanding, and device performance enabled rapid progress which eventually led to the successful fabrication of state of the art HEMT transistors and amplifiers.

Kurtz, Steven Ross; Follstaedt, David Martin; Wright, Alan Francis; Baca, Albert G.; Briggs, Ronald D.; Provencio, Paula Polyak; Missert, Nancy A.; Allerman, Andrew Alan; Marsh, Phil F.; Koleske, Daniel David; Lee, Stephen Roger; Shul, Randy John; Seager, Carleton Hoover; Tigges, Christopher P.

2005-12-01T23:59:59.000Z

217

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...

218

T4, Morphological Development of Homoepitaxial AlN Thin Films ...  

Science Conference Proceedings (OSTI)

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

219

Step-Wise Exothermic Reactions in Cold-Rolled Ni/Al, Ti/Al, and Ta ...  

Science Conference Proceedings (OSTI)

Aerosol Route Synthesis of Copper Oxide Nanoparticles Using Copper Nitrate Solution · AlGaAs-Based Optical ... Defect Energetics and Fission Product Transport in ZrC ... Enhancing Mineral Beneficiation by High Intensity Power Ultrasound.

220

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 ...

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Index
221

InGaAS detectors for miniature infrared instruments T.N. Krabach, C. Staller, S. Dejewski, T. Cunningham, M. Herring, and E.R. Fossum  

E-Print Network (OSTI)

. The spacecraft and mission limitations of solar power also apply to these alternative power systems. Coolers of peak solar illumination. In this region, the primary phenomenology of interest is the reflectance imaging system, of which some variant has been flown on virtually every scientific space mission. Imaging

Fossum, Eric R.

222

Low-cost, high-efficiency solar cells utilizing GaAs-on-Si technology  

DOE Green Energy (OSTI)

This report describes work to develop technology to deposit GaAs on Si using a nucleation layer of atomic-layer-epitaxy-grown GaAs or AlAs on Si. This ensures two-dimensional nucleation and should lead to fewer defects in the final GaAs layer. As an alternative, we also developed technology for depositing GaAs on sawtooth-patterned Si. Preliminary studies showed that this material can have a very low defect density, [approximately] 1 [times] 10[sup 5] cm[sup [minus]5], as opposed to our conventionally grown GaAs on SL which has a typical defect density of over 1 [times]10[sup 7] cm[sup [minus]2]. Using these two now methods of GaAs-on-Si material growth, we made solar cells that are expected to show higher efficiencies than those of previous cells.

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

1993-04-01T23:59:59.000Z

223

Polarity inversion of N-face GaN using an aluminum oxide interlayer  

Science Conference Proceedings (OSTI)

The polarity of GaN grown by plasma-assisted molecular beam epitaxy was inverted from N-face to Ga-face by inserting a composite AlN/aluminum oxide (AlO{sub x}) interlayer structure at the inversion interface. The change in polarity was verified in situ by reflection high energy electron diffraction via intensity transients and postgrowth surface reconstructions, and ex situ by convergent beam electron diffraction and etch studies in an aqueous potassium hydroxide solution. The inverted materials showed smooth surfaces and good electrical properties. AlGaN/GaN high electron mobility transistors fabricated on the inverted epilayers showed good dc and high frequency performance. A current-gain cutoff frequency (f{sub T}) of 21 GHz and maximum oscillation frequency (f{sub max}) of 61 GHz were measured in devices with a gate length of 0.7 {mu}m. These data compare favorably to those of Ga-face AlGaN/GaN devices with a similar structure grown on Si-face SiC substrates.

Wong, Man Hoi; Mishra, Umesh K. [Department of Electrical and Computer Engineering, University of California, Santa Barbara, California 93106-9560 (United States); Wu, Feng; Speck, James S. [Materials Department, University of California, Santa Barbara, California 93106-5050 (United States)

2010-12-15T23:59:59.000Z

224

ALS@20  

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

feed-image feed-image Digg: ALSBerkeleyLab Facebook Page: 208064938929 Flickr: advancedlightsource Twitter: ALSBerkeleyLab YouTube: AdvancedLightSource Home About the ALS ALS@20 ALS@20 ALS@20 Kick-Off Celebration Print On Friday, January 11, the Advanced Light Source celebrated the beginning of its 20th anniversary year with a brunch attended by more than 150 current and past staff members. After introductory remarks describing the trials and tribulations encountered during the construction of the ALS from former Director Jay Marx, current ALS Scientific Director Steve Kevan and Director Roger Falcone talked about the progress of the facility over the years. Attendees were then able to view more than 500 historical photos of the ALS and its staff displayed around the room.

225

Growth and development of GaInAsP for use in high-efficiency solar cells. Annual subcontract report, 1 July 1991--30 June 1992  

DOE Green Energy (OSTI)

This report describes work done during Phase II of the subcontract. Goals for Phase II include the following: (1) Optimize the GaInAsP cell on GaAs and demonstrate a 500-sun at air mass (AM) 1.5 efficiency of >23%. (2) Develop a window layer, including the evaluation of AlGaAs, GaInP, AlGaAsP, AlGaInP, and GaP. (3) Develop a front-surface contact, with a grid designed for 500-sun concentration, and a goal of a contact resistivity of {approximately}10{sup 5} ohm-cm{sup 2}. (4) Grow GaInAsP cells on Ge, with a goal of a 1-sun (AM 1.5) efficiency of >15%. Accomplishments reported herein include (1) the fabrication of p-on-n and n-on-p GaInAsP cells on GaAs, with the n-on-p cell demonstrating a 10-sun (AM 1.5) active-area efficiency of 23.4% as measured at NREL (2) the evaluation of Al{sub x}Ga({sub 1-x})As, GaInP{sub 2}, and AlInP{sub 2} window layers; and (3) the fabrication of GaInAsP cells on Ge, with the demonstration of a p-on-n GaInAsP cell grown on Ge with a 1-sun (AM 1.5) active-area efficiency of 14.4%.

Sharps, P.R. [Research Triangle Inst., Research Triangle Park, NC (United States)

1993-04-01T23:59:59.000Z

226

Photoluminescence study of the 1.047 eV emission in GaN K. Pressela)  

E-Print Network (OSTI)

GaN/ AlGaN blue green light emitting diode, which has a much higher quantum efficiency than the SiC blue light emitting diode, became possible.2 Presently the wide bandgap semi- conductor GaN is intensively. Especially the 1.19 eV is very intense. Thus one can think of developing a light emitting diode in the near

Nabben, Reinhard

227

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

228

Polarization-engineered GaN/InGaN/GaN tunnel diodes  

E-Print Network (OSTI)

We report on the design and demonstration of polarization-engineered GaN/InGaN/GaN tunnel junction diodes with high current density and low tunneling turn-on voltage. Wentzel-Kramers-Brillouin (WKB) calculations were used to model and design tunnel junctions with narrow bandgap InGaN-based barrier layers. N-polar p-GaN/In0.33Ga0.67N/n-GaN heterostructure tunnel diodes were grown using molecular beam epitaxy. Efficient zero bias tunneling turn-on with a high current density of 118 A/cm2 at a reverse bias of 1V, reaching a maximum current density up to 9.2 kA/cm2 were obtained. These results represent the highest current density reported in III-nitride tunnel junctions, and demonstrate the potential of III-nitride tunnel devices for a broad range of optoelectronic and electronic applications.

Sriram Krishnamoorthy; Digbijoy N. Nath; Fatih Akyol; Pil Sung Park; Michele Esposto; Siddharth Rajan

2010-08-24T23:59:59.000Z

229

Industry @ ALS  

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

Industry @ ALS Industry @ ALS Industry @ ALS Concrete Industry Benefits from Ancient Romans and the ALS Print Thursday, 17 October 2013 14:24 New insights into the Romans' ingenious concrete harbor structures emerging from ALS beamline research could move the modern concrete industry toward its goal of a reduced carbon footprint. Summary Slide Read more... Moving Industry Forward: Finding the Environmental Opportunity in Biochar Print Thursday, 12 September 2013 08:41 Using ALS Beamlines 10.3.2 and 8.3.2, the Environmental Protection Agency (EPA) is currently investigating how biochar sorbs environmental toxins and which kinds of biochar are the most effective. The possibilities for widespread use have already launched entrepreneurial commercial ventures. Summary Slide

230

Electron mobility and effective mass in composite InGaAs quantum wells with InAs and GaAs nanoinserts  

Science Conference Proceedings (OSTI)

The paper is concerned with the theoretical and experimental studies of the band structure and electrical properties of InAlAs/InGaAs/InAlAs/InP heterostructures containing a composite InGaAs quantum well with InAs and GaAs nanoinserts. From the Shubnikov-de Haas effect, the effective cyclotron mass m{sub c}* is determined experimentally and calculated with consideration for the nonparabolicity of the electron energy spectrum. An approach to estimation of the effective mass is proposed and tested. The approach is based on weighted averaging of the m{sub c}* of the composite quantum well's constituent materials. A first proposed heterostructure containing two InAs inserts symmetrically arranged in the quantum well makes a 26% reduction in m{sub c}* compared to m{sub c}* in the lattice-matched In{sub 0.53}Ga{sub 0.47}As quantum well possible.

Ponomarev, D. S., E-mail: ponomarev_dmitr@mail.ru; Vasil'evskii, I. S. [National Nuclear Research University 'Moscow Engineering Physics Institute (MEPhI)' (Russian Federation); Galiev, G. B.; Klimov, E. A. [Russian Academy of Sciences, Institute of Ultrahigh-Frequency Semiconductor Electronics (Russian Federation); Khabibullin, R. A. [National Nuclear Research University 'Moscow Engineering Physics Institute (MEPhI)' (Russian Federation); Kulbachinskii, V. A.; Uzeeva, N. A. [Moscow State University (Russian Federation)

2012-04-15T23:59:59.000Z

231

ALS Visitors  

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

Energy. March 2010 ALS Project Manager Steve Rossi hosted a group of visitors from Kazakhstan on Friday, March 5. The visitors, including a representative from the Kazakhstan...

232

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

DOE Green Energy (OSTI)

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

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

1998-11-24T23:59:59.000Z

233

ALS Visitors  

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

ALS Visitors ALS Visitors ALS Visitors Print Wednesday, 29 July 2009 00:00 ALS staff members host a variety of scientific, educational, government, and community-related tours each month. November 2013 poneman U.S. Deputy Secretary of Energy Daniel Poneman visited Berkeley Lab on Friday, Nov. 15, during a brief stay in the Bay Area. Glenn Mara of the University of California Office of the President and Aundra Richards of the DOE Berkeley Site Office joined Deputy Laboratory Director Horst Simon's welcome. They updated Poneman on the lab's future initiatives and current capital projects and heard briefings on cyber security, computing, and the Joint BioEnergy Institute. As second-in-command at DOE, Poneman is responsible for assisting the Secretary of Energy in the management and operations of the agency and acting on his behalf when necessary.During his tour of the ALS, Poneman (right) spoke with Ken Goldberg (Materials Sciences Division) at the CXRO beamline.

234

GA SNC Solar | Open Energy Information  

Open Energy Info (EERE)

GA SNC Solar Jump to: navigation, search Name GA-SNC Solar Place Nevada Sector Solar Product Nevada-based PV project developer and joint venture of GA-Solar North America and...

235

Category:Savannah, GA | Open Energy Information  

Open Energy Info (EERE)

Savannah, GA Savannah, GA Jump to: navigation, search Go Back to PV Economics By Location Media in category "Savannah, GA" The following 16 files are in this category, out of 16 total. SVFullServiceRestaurant Savannah GA Georgia Power Co.png SVFullServiceRestauran... 80 KB SVHospital Savannah GA Georgia Power Co.png SVHospital Savannah GA... 80 KB SVLargeHotel Savannah GA Georgia Power Co.png SVLargeHotel Savannah ... 75 KB SVLargeOffice Savannah GA Georgia Power Co.png SVLargeOffice Savannah... 82 KB SVMediumOffice Savannah GA Georgia Power Co.png SVMediumOffice Savanna... 85 KB SVMidriseApartment Savannah GA Georgia Power Co.png SVMidriseApartment Sav... 80 KB SVOutPatient Savannah GA Georgia Power Co.png SVOutPatient Savannah ... 84 KB SVPrimarySchool Savannah GA Georgia Power Co.png

236

Category:Atlanta, GA | Open Energy Information  

Open Energy Info (EERE)

GA GA Jump to: navigation, search Go Back to PV Economics By Location Media in category "Atlanta, GA" The following 16 files are in this category, out of 16 total. SVFullServiceRestaurant Atlanta GA Georgia Power Co.png SVFullServiceRestauran... 81 KB SVHospital Atlanta GA Georgia Power Co.png SVHospital Atlanta GA ... 81 KB SVLargeHotel Atlanta GA Georgia Power Co.png SVLargeHotel Atlanta G... 74 KB SVLargeOffice Atlanta GA Georgia Power Co.png SVLargeOffice Atlanta ... 82 KB SVMediumOffice Atlanta GA Georgia Power Co.png SVMediumOffice Atlanta... 84 KB SVMidriseApartment Atlanta GA Georgia Power Co.png SVMidriseApartment Atl... 82 KB SVOutPatient Atlanta GA Georgia Power Co.png SVOutPatient Atlanta G... 83 KB SVPrimarySchool Atlanta GA Georgia Power Co.png SVPrimarySchool Atlant...

237

Annual Performance Evaluation of a Pair of Energy Efficient Houses (WC3 and WC4) in Oak Ridge, TN  

SciTech Connect

Beginning in 2008, two pairs of energy-saver houses were built at Wolf Creek in Oak Ridge, TN. These houses were designed to maximize energy efficiency using new ultra-high-efficiency components emerging from ORNL s Cooperative Research and Development Agreement (CRADA) partners and others. The first two houses contained 3713 square feet of conditioned area and were designated as WC1 and WC2; the second pair consisted of 2721 square feet conditioned area with crawlspace foundation and they re called WC3 and WC4. This report is focused on the annual energy performance of WC3 and WC4, and how they compare against a previously benchmarked maximum energy efficient house of a similar footprint. WC3 and WC4 are both about 55-60% more efficient than traditional new construction. Each house showcases a different envelope system: WC3 is built with advanced framing featured cellulose insulation partially mixed with phase change materials (PCM); and WC4 house has cladding composed of an exterior insulation and finish system (EIFS). The previously benchmarked house was one of three built at the Campbell Creek subdivision in Knoxville, TN. This house (CC3) was designed as a transformation of a builder house (CC1) with the most advanced energy-efficiency features, including solar electricity and hot water, which market conditions are likely to permit within the 2012 2015 period. The builder house itself was representative of a standard, IECC 2006 code-certified, all-electric house built by the builder to sell around 2005 2008.

Biswas, Kaushik [ORNL; Christian, Jeffrey E [ORNL; Gehl, Anthony C [ORNL; Jackson, Roderick K [ORNL; Boudreaux, Philip R [ORNL

2012-04-01T23:59:59.000Z

238

ALS Visitors  

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

ALS Visitors Print ALS Visitors Print ALS staff members host a variety of scientific, educational, government, and community-related tours each month. November 2013 poneman U.S. Deputy Secretary of Energy Daniel Poneman visited Berkeley Lab on Friday, Nov. 15, during a brief stay in the Bay Area. Glenn Mara of the University of California Office of the President and Aundra Richards of the DOE Berkeley Site Office joined Deputy Laboratory Director Horst Simon's welcome. They updated Poneman on the lab's future initiatives and current capital projects and heard briefings on cyber security, computing, and the Joint BioEnergy Institute. As second-in-command at DOE, Poneman is responsible for assisting the Secretary of Energy in the management and operations of the agency and acting on his behalf when necessary.During his tour of the ALS, Poneman (right) spoke with Ken Goldberg (Materials Sciences Division) at the CXRO beamline.

239

Al Weinrub  

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

Al Weinrub Al Weinrub Author, "COMMUNITY POWER: Decentralized Renewable Energy in California" Member, Sierra Club California Clean Energy-Climate CommitteeMember, Steering Committee, Bay Area Clean Energy Alliance al.weinrub@comcast.net This speaker was a visiting speaker who delivered a talk or talks on the date(s) shown at the links below. This speaker is not otherwise associated with Lawrence Berkeley National Laboratory, unless specifically identified as a Berkeley Lab staff member. Al Weinrub is a member of the Sierra Club California Energy-Climate Committee and serves on the Steering Committee of the Bay Area's Local Clean Energy Alliance. He is the author of COMMUNITY POWER: Decentralized Renewable Energy in California (http://www.localcleanenergy.org/Community-Power-Publication)

240

Al Gallo  

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

As the Director for the Office of Technology Evaluation, Al Gallo works closely with the Chief Technology Officer as well as many Program Offices to advance the introduction and adoption of...

Index
Note: This page contains sample records for the topic "tn al ga" 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.


Index
241

ALS Visitors  

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

Quick Facts Quick Facts ALS Visitors Print ALS staff members host a variety of scientific, educational, government, and community-related tours each month. November 2013 poneman U.S. Deputy Secretary of Energy Daniel Poneman visited Berkeley Lab on Friday, Nov. 15, during a brief stay in the Bay Area. Glenn Mara of the University of California Office of the President and Aundra Richards of the DOE Berkeley Site Office joined Deputy Laboratory Director Horst Simon's welcome. They updated Poneman on the lab's future initiatives and current capital projects and heard briefings on cyber security, computing, and the Joint BioEnergy Institute. As second-in-command at DOE, Poneman is responsible for assisting the Secretary of Energy in the management and operations of the agency and acting on his behalf when necessary.During his tour of the ALS, Poneman (right) spoke with Ken Goldberg (Materials Sciences Division) at the CXRO beamline.

242

Atomic structure and energy spectrum of Ga(As,P)/GaP heterostructures  

Science Conference Proceedings (OSTI)

The atomic structure and energy spectrum of Ga(As,P)/GaP heterostructures were studied. It was shown that the deposition of GaAs of the same nominal thickness leads to the formation of pseudomorphic GaAs/GaP quantum wells (QW), fully relaxed GaAs/GaP self-assembled quantum dots (SAQDs), or pseudomorphic GaAsP/GaP SAQDs depending on the growth temperature. We demonstrate that the atomic structure of Ga(As,P)/GaP heterostructures is ruled by the temperature dependence of adatom diffusion rate and GaAs-GaP intermixing. The band alignment of pseudomorphic GaAs/GaP QW and GaAsP/GaP SAQDs is shown to be of type II, in contrast to that of fully relaxed GaAs/GaP SAQDs, which have the band alignment of type I with the lowest electronic states at the indirect L valley of the GaAs conduction band.

Abramkin, D. S.; Putyato, M. A.; Budennyy, S. A.; Gutakovskii, A. K.; Semyagin, B. R.; Preobrazhenskii, V. V.; Shamirzaev, T. S. [A. V. Rzhanov Institute of Semiconductor Physics, Siberian Branch of the Russian Academy of Sciences, Pr. Lavrentyeva 13, 630090 Novosibirsk (Russian Federation); Kolomys, O. F.; Strelchuk, V. V. [V. E. Lashkarev Institute of Semiconductor Physics NAS of Ukraine, Pr. Nauki 41, 03028 Kiev (Ukraine)

2012-10-15T23:59:59.000Z

243

Fabrication of the Mg/Al clad sheet and its mechanical properties  

Science Conference Proceedings (OSTI)

Aerosol Route Synthesis of Copper Oxide Nanoparticles Using Copper Nitrate Solution · AlGaAs-Based Optical ... Defect Energetics and Fission Product Transport in ZrC ... Enhancing Mineral Beneficiation by High Intensity Power Ultrasound.

244

Impact toughness Enhancement of an Electron Beam Welded Ti-6Al ...  

Science Conference Proceedings (OSTI)

Aerosol Route Synthesis of Copper Oxide Nanoparticles Using Copper Nitrate Solution · AlGaAs-Based Optical ... Defect Energetics and Fission Product Transport in ZrC ... Enhancing Mineral Beneficiation by High Intensity Power Ultrasound.

245

Pressurless sintering of Al2O3-SiC nano composites and effect of ...  

Science Conference Proceedings (OSTI)

Aerosol Route Synthesis of Copper Oxide Nanoparticles Using Copper Nitrate Solution · AlGaAs-Based Optical ... Defect Energetics and Fission Product Transport in ZrC ... Enhancing Mineral Beneficiation by High Intensity Power Ultrasound.

246

Impacts of impurities on the Properties of Secondary Al-Si-Cu alloys  

Science Conference Proceedings (OSTI)

Aerosol Route Synthesis of Copper Oxide Nanoparticles Using Copper Nitrate Solution · AlGaAs-Based Optical ... Defect Energetics and Fission Product Transport in ZrC ... Enhancing Mineral Beneficiation by High Intensity Power Ultrasound.

247

The use of short-period InGaN/GaN superlattices in blue-region light-emitting diodes  

SciTech Connect

Optical and light-emitting diode structures with an active InGaN region containing short-period InGaN/GaN superlattices are studied. It is shown that short-period superlattices are thin two-dimensional layers with a relatively low In content that contain inclusions with a high In content 1-3 nm thick. Inclusions manifest themselves from the point of view of optical properties as a nonuniform array of quantum dots involved in a residual quantum well. The use of short-period superlattices in light-emitting diode structures allows one to decrease the concentration of nonradiative centers, as well as to increase the injection of carriers in the active region due to an increase in the effective height of the AlGaN barrier, which in general leads to an increase in the quantum efficiency of light-emitting diodes.

Sizov, V. S., E-mail: vsizov@mail.ioffe.ru; Tsatsulnikov, A. F.; Sakharov, A. V.; Lundin, W. V.; Zavarin, E. E.; Cherkashin, N. A. [Russian Academy of Sciences, Ioffe Physical Technical Institute (Russian Federation); Hytch, M. J. [National Center for Scientific Research (CNRS), Center for Material Elaboration and Structural Studies (CEMES) (France); Nikolaev, A. E. [Russian Academy of Sciences, Ioffe Physical Technical Institute (Russian Federation); Mintairov, A. M.; He Yan; Merz, J. L. [University of Notre Dame, EE Department (United States)

2010-07-15T23:59:59.000Z

248

General Atomics (GA) Fusion News: A New Spin on Understanding...  

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

General Atomics (GA) Fusion News: A New Spin on Understanding Plasma Confinement American Fusion News Category: General Atomics (GA) Link: General Atomics (GA) Fusion News: A New...

249

Rodefeld Landfill Ga Biomass Facility | Open Energy Information  

Open Energy Info (EERE)

Rodefeld Landfill Ga Biomass Facility Jump to: navigation, search Name Rodefeld Landfill Ga Biomass Facility Facility Rodefeld Landfill Ga Sector Biomass Facility Type Landfill Gas...

250

GaAs/AlGaAs nanostructured composites for free-space and integrated optical devices  

E-Print Network (OSTI)

A. Vawter, and J. R. Wendt, ‘‘High-aspect-ratio nanophotonicJ. D. Joannopoulos, J. R. Wendt, G. A. Vawter, W. Zubrzycki,A. Vawter, and J. R. Wendt, ‘‘High-aspect-ratio nanophotonic

Tsai, Chia-Ho

2006-01-01T23:59:59.000Z

251

Persistent photoconductivity and defect levels in n-type AlGaN/GaN heterostructures  

E-Print Network (OSTI)

of California at San Diego, La Jolla, California 92093-0407 K. S. Boutros and J. M. Redwing Epitronics

Yu, Edward T.

252

Measurement of drift mobility in AlGaN/GaN heterostructure field-effect transistor  

E-Print Network (OSTI)

Center, Thousand Oaks, California 91358 K. S. Boutros and J. M. Redwing Epitronics/ATMI, Phoenix, Arizona

Yu, Edward T.

253

NIVEAUX PROFONDS DANS LES DIODES LECTROLUMINESCENTES GaAs-GaAlAs  

E-Print Network (OSTI)

JEPPSON, B., Jpn. J. Appl. Phys. 12 (1973) 1011. [15] LANG, D. V., CHO, A. Y., GOSSARD, A. C. et WIEGMANN

Paris-Sud XI, Université de

254

GaAs/AlGaAs nanostructured composites for free-space and integrated optical devices  

E-Print Network (OSTI)

Optics : Electromagnetic Theory of Propagation, InterferenceOptics : Electromagnetic Theory of Propagation, Interference

Tsai, Chia-Ho

2006-01-01T23:59:59.000Z

255

KK9, Nanostructure Decorated AlGaN/GaN HEMTs for Chemical ...  

Science Conference Proceedings (OSTI)

The high sensitivity of ZnO, towards the exposure to NH3, H2, O3, CO, NO2, and ethanol etc., makes it viable for gas sensing applications. Similarly, the same ...

256

JJ5, Electro-Thermo-Mechanical Simulation of AlGaN/GaN HFETs ...  

Science Conference Proceedings (OSTI)

Recently, gate insulation has shown to significantly reduce the leakage .... E6, Development of Surface Activation Based Nano-Bonding and Interconnect System ... Microstructure and Properties of Colloidal ITO Films and Cold- Sputtered ITO ...

257

Characteristics of AlGaAs/GaAs heterostructure RT-SCR model  

Science Conference Proceedings (OSTI)

Electrical properties of a resonant-tunneling-semiconductor-controlled rectifier (RT-SCR) model have been presented. The current, temperature, gain, doping concentration, and layer size versus voltage relationships have been numerically obtained. The ... Keywords: RT-SCR, Semiconductor devices, Thyristors

B. D. Barkana

2008-12-01T23:59:59.000Z

258

Life tests of Nichia AlGaN/InGaN/GaN blue-light-emitting diodes  

SciTech Connect

We report on results of life testing Nichia NLPB500 blue LEDs in a temperature controlled chamber, with computer automation of equipment operation and data collection. The tests began with 18 newer (Nichia batch 4B0001) and two older (Nichia batch S403024, acquired a year earlier) LEDs, operated at 20 mA continuous wave (CW) and 23{degree}C. Light from each LED was coupled to an optical fiber and fed directly to individual photodetectors. General trend for the 18 newer LEDs was for the output intensity to increase at a faster rate within the first 50 h and then at a slower rate of the remainder of the first test. The output intensity of the two older LEDs increase within the first 50 h then decreased during the remainder of the first 1000 h. All 20 of the LEDs in the first 1000-h test were subjected to a second 1650-h test at 23{degree}C and at currents 20-70 mA CW. Only one LED, an older device, suffered a soft failure during this second test. The remaining LEDs underwent a third test at 30{degree}C and a fourth test at 35{degree}C, all at various currents. We will perform failure analysis.

Helms, C.J.; Berg, N.H.; Barton, D.L.; Osinski, M

1996-03-01T23:59:59.000Z

259

Tunnel-injection GaN quantum dot ultraviolet light-emitting diodes  

SciTech Connect

We demonstrate a GaN quantum dot ultraviolet light-emitting diode that uses tunnel injection of carriers through AlN barriers into the active region. The quantum dot heterostructure is grown by molecular beam epitaxy on AlN templates. The large lattice mismatch between GaN and AlN favors the formation of GaN quantum dots in the Stranski-Krastanov growth mode. Carrier injection by tunneling can mitigate losses incurred in hot-carrier injection in light emitting heterostructures. To achieve tunnel injection, relatively low composition AlGaN is used for n- and p-type layers to simultaneously take advantage of effective band alignment and efficient doping. The small height of the quantum dots results in short-wavelength emission and are simultaneously an effective tool to fight the reduction of oscillator strength from quantum-confined Stark effect due to polarization fields. The strong quantum confinement results in room-temperature electroluminescence peaks at 261 and 340 nm, well above the 365 nm bandgap of bulk GaN. The demonstration opens the doorway to exploit many varied features of quantum dot physics to realize high-efficiency short-wavelength light sources.

Verma, Jai; Kandaswamy, Prem Kumar; Protasenko, Vladimir; Verma, Amit; Grace Xing, Huili; Jena, Debdeep [Department of Electrical Engineering, University of Notre Dame, Indiana 46556 (United States)] [Department of Electrical Engineering, University of Notre Dame, Indiana 46556 (United States)

2013-01-28T23:59:59.000Z

260

AL. I  

Office of Legacy Management (LM)

AL. I AL. I Department of Energy Washington, DC 20545 OCT 13 Vii87 Mr. John T. Shields A214 National Fertilizer Development Center Tennessee Valley Authority Muscle Shoals, Alabama 35660 Dear Mr. Shields: As you may know, the Department of Energy (DOE) is evaluating the radiological condition of sites that were utilized under the Manhattan Engineer District and the Atomic Energy Commission (AEC) during the early years of nuclear development to determine whether they need remedial action and whether the Department has authority to perform such action. AEC work at the TVA during the period 1951 through 1955 involved the development of a process to recover uranium from the production of phosphate fertilizer. A laboratory and pilot plant were operated at the site, but very little

Index
Note: This page contains sample records for the topic "tn al ga" 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.


Index
261

RECIPIENT:Gwinnett Co, GA  

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

Gwinnett Co, GA Gwinnett Co, GA u.s DEPARUIENT OFENllRGY EERE PROJECT MANAGEMENT CENTER NllPA DETERl\JINATION PROJECr TITLE: Gwinnett Co, GA EEC8G Page I or2 STATE: GA Funding Opportunity Announcement Number Procu~ment Instrument Number N[PA Control Number CID Number DE-EEOOOOS05.005 0 Based on my review ortbe information concerning tbe proposed action, as NEPA Compliance Officer (authorized under DOE Order 4SI.IA), I bave made the following determination: ex, EA, EIS APPENDIX AND NUMBER: Description: 8 5.1 Actions to conserve energy, demonstrate potential energy conservation, and promote energy-efficiency that do not increase the indoor concentrations of potentially harmful substances. These actions may involve financial and technical assistance to individuals (such as builders, owners, consultants, designers), organizations (such as utilities), and state

262

TN_50mwind  

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

taTechnologySpecificUnitedStatesWindHighResolutionTennesseeWindHighResolution.zip> Description: Abstract: Annual average wind resource potential for the state of...

263

TN1421 - References  

Science Conference Proceedings (OSTI)

... 1914; WW Coblentz, "Studies of Instruments for Measuring Radiant Energy in Absolute ... JE Martin, NP Fox and PJ Keys, "A cryogenic radiometer of ...

264

Figure 23. Average price of natural gas delivered to U.S. commercial...  

Annual Energy Outlook 2012 (EIA)

Natural and Supplemental Gas Supply and Disposition," and Form EIA-910, "Monthly Natural Gas Marketer Survey." IN OH TN WV VA KY MD PA NY VT NH MA CT ME RI DE DC NC SC GA FL NJ AL...

265

Microsoft Word - figure_22.doc  

Gasoline and Diesel Fuel Update (EIA)

Natural and Supplemental Gas Supply and Disposition," and Form EIA-910, "Monthly Natural Gas Marketer Survey." IN OH TN WV VA KY MD PA NY VT NH MA CT ME RI DE DC NC SC GA FL NJ AL...

266

Intense terahertz emission from molecular beam epitaxy-grown GaAs/GaSb(001)  

SciTech Connect

Intense terahertz (THz) electromagnetic wave emission was observed in undoped GaAs thin films deposited on (100) n-GaSb substrates via molecular beam epitaxy. GaAs/n-GaSb heterostructures were found to be viable THz sources having signal amplitude 75% that of bulk p-InAs. The GaAs films were grown by interruption method during the growth initiation and using various metamorphic buffer layers. Reciprocal space maps revealed that the GaAs epilayers are tensile relaxed. Defects at the i-GaAs/n-GaSb interface were confirmed by scanning electron microscope images. Band calculations were performed to infer the depletion region and electric field at the i-GaAs/n-GaSb and the air-GaAs interfaces. However, the resulting band calculations were found to be insufficient to explain the THz emission. The enhanced THz emission is currently attributed to a piezoelectric field induced by incoherent strain and defects.

Sadia, Cyril P.; Laganapan, Aleena Maria; Agatha Tumanguil, Mae; Estacio, Elmer; Somintac, Armando; Salvador, Arnel [National Institute of Physics, University of the Philippines Diliman, Quezon City 1101 (Philippines); Que, Christopher T. [Physics Department, De La Salle University, 2401 Taft Avenue, Manila 1004 (Philippines); Yamamoto, Kohji; Tani, Masahiko [Research Center for Development of Far-Infrared Region, University of Fukui, Fukui 910-8507 (Japan)

2012-12-15T23:59:59.000Z

267

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

268

New GaInP/GaAs/GaInAs, Triple-Bandgap, Tandem Solar Cell for High-Efficiency Terrestrial Concentrator Systems  

DOE Green Energy (OSTI)

GaInP/GaAs/GaInAs three-junction cells are grown in an inverted configuration on GaAs, allowing high quality growth of the lattice matched GaInP and GaAs layers before a grade is used for the 1-eV GaInAs layer. Using this approach an efficiency of 37.9% was demonstrated.

Kurtz, S.; Wanlass, M.; Kramer, C.; Young, M.; Geisz, J.; Ward, S.; Duda, A.; Moriarty, T.; Carapella, J.; Ahrenkiel, P.; Emery. K.; Jones, K.; Romero, M.; Kibbler, A.; Olson, J.; Friedman, D.; McMahon, W.; Ptak, A.

2005-11-01T23:59:59.000Z

269

Development of polycrystal GaAs solar cells. Quarterly technical progress report No. 1, January 15-April 30, 1979  

DOE Green Energy (OSTI)

The objective of this program is to develop a thin film GaAs solar cell technology with the potential of yielding cells with 12 to 15% efficiency and to develop thin film growth techniques which are compatible with the low cost production goal of $500/kW-peak. Progress is reported on a study of junction formation in large grain polycrystal GaAs; characterization of the electronic properties of polycrystal GaAs grown by MBE on low cost foreign substrates; optimizing the structure of AlGaAs-GaAs heterojunction Schottky barrier solar cells; and a variety of grain boundary measurements, including Scanning Light Microscopy (SLM), Deep Level Transient Spectroscopy (DLTS), SIMS, and temperature dependent resistivity.

Miller, D.L.; Cohen, M.J.; Harris, J.S. Jr.; Ballantyne, J.; Hoyte, A.; Stefanakos, E.

1979-05-01T23:59:59.000Z

270

Low-cost, high-efficiency solar cells utilizing GaAs-on-Si technology. Annual subcontract report, 1 August 1991--31 July 1992  

DOE Green Energy (OSTI)

This report describes work to develop technology to deposit GaAs on Si using a nucleation layer of atomic-layer-epitaxy-grown GaAs or AlAs on Si. This ensures two-dimensional nucleation and should lead to fewer defects in the final GaAs layer. As an alternative, we also developed technology for depositing GaAs on sawtooth-patterned Si. Preliminary studies showed that this material can have a very low defect density, {approximately} 1 {times} 10{sup 5} cm{sup {minus}5}, as opposed to our conventionally grown GaAs on SL which has a typical defect density of over 1 {times}10{sup 7} cm{sup {minus}2}. Using these two now methods of GaAs-on-Si material growth, we made solar cells that are expected to show higher efficiencies than those of previous cells.

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

1993-04-01T23:59:59.000Z

271

Efficiency-improvement study for GaAs solar cells. Final report, March 31, 1980-September 30, 1981  

DOE Green Energy (OSTI)

High-yield fabrication of good quality AlGaAs/GaAs concentration solar cells has been a limiting factor in widespread utilization of these high conversion efficiency (22 to 24%) photovoltaic cells. Reported is a series of investigations to correlate solar cell yield with substrate quality, growth techniques, layer composition, and metallization processes. In addition, several diagnostic techniques are described to aid in device characterization.

Cape, J.A.; Oliver, J.R.; Zehr, S.W.

1982-04-01T23:59:59.000Z

272

Ultra-low resistance ohmic contacts to GaN with high Si doping concentrations grown by molecular beam epitaxy  

Science Conference Proceedings (OSTI)

Ti/Al/Ni/Au ohmic contacts were formed on heavily doped n{sup +} metal-polar GaN samples with various Si doping concentrations grown by molecular beam epitaxy. The contact resistivity (R{sub C}) and sheet resistance (R{sub sh}) as a function of corresponding GaN free carrier concentration (n) were measured. Very low R{sub C} values (electron mobility transistors.

Afroz Faria, Faiza; Guo Jia; Zhao Pei; Li Guowang; Kumar Kandaswamy, Prem; Wistey, Mark; Xing Huili; Jena, Debdeep [Department of Electrical Engineering, University of Notre Dame, Indiana 46556 (United States)

2012-07-16T23:59:59.000Z

273

Direct evidence of the fermi-energy-dependent formation of Mn interstitials in modulation doped Ga1-yAlyAs/Ga1-xMnxAs/Ga1-yAlyAs heterostructures  

SciTech Connect

Using ion channeling techniques, we investigate the lattice locations of Mn in Ga{sub 1-x}Mn{sub x}As quantum wells between Be-doped Ga{sub 1-y}Al{sub y}As barriers. The earlier results showed that the Curie temperature T{sub C} depends on the growth sequence of the epitaxial layers. A lower T{sub C} was found in heterostructures in which the Ga{sub 1-x}Mn{sub x}As layer is grown after the modulation-doped barrier. Here we provide direct evidence that this reduction in T{sub C} is directly correlated with an increased formation of magnetically inactive Mn interstitials. The formation of interstitials is induced by a shift of the Fermi energy as a result of the transfer of holes from the barrier to the quantum well during the growth.

Yu, K.M.; Walukiewicz, W.; Wojtowicz, T.; Lim, W.L.; Liu, X.; Dobrowolska, M.; Furdyna, J.K.

2004-01-30T23:59:59.000Z

274

ALS Project Management Manual  

E-Print Network (OSTI)

management practices across all ALS projects. It describesthat the primary weakness in ALS project management effortsrich projects common at the ALS. It is sometimes difficult

Krupnick, Jim; Harkins, Joe

2000-01-01T23:59:59.000Z

275

HH7, Degradation of Ohmic and Schottky Contacts on InGaAs ...  

Science Conference Proceedings (OSTI)

In order to study the device reliability and failure mechanisms, both high ... InAlAs /InGaAs MHEMTs, obtained from a vendor, were stressed for 36 hours at a drain voltage of 3V. ... Transmission line method (TLM) structures were also stressed under similar .... Epitaxial Graphene: Designing a New Electronic Material.

276

Strong et al ALS FTD consensus criteria  

E-Print Network (OSTI)

Strong et al ALS FTD consensus criteria 1 Version: 20070606 Frontotemporal syndromes in amyotrophic, UCSF, San Francisco, California, USA (5) Forbes Norris MDA/ALS Research Center, San Francisco Kingdom (8) Science Director & Vice President, The ALS Association, Palm Harbor, Florida, U.S.A. (9

Dickerson, Brad

277

Access to the ALS  

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

Access to the ALS Access to the ALS Print User Access The ALS experiment floor (Building 6) is a Controlled Access Area for radiation protection. All ALS users are required to...

278

Access to the ALS  

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

Access to the ALS Print User Access The ALS experiment floor (Building 6) is a Controlled Access Area for radiation protection. All ALS users are required to register with the ALS...

279

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 0GaAs layer, with the InGaAsN and GaAs layers being lattice-matched to the substrate. The InGaAsN/GaAs p-n heterojunction can be epitaxially grown by either molecular beam epitaxy (MBE) or metalorganic chemical vapor deposition (MOCVD). The InGaAsN/GaAs p-n heterojunction provides a high open-circuit voltage of up to 0.62 volts and an internal quantum efficiency of >70%.

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

280

Magnetism and transport properties of epitaxial Fe-Ga thin films on GaAs(001)  

SciTech Connect

Epitaxial Fe-Ga thin films in disordered bcc {alpha}-Fe crystal structure (A2) have been grown on GaAs(001) by molecular beam epitaxy. The saturated magnetization (M{sub S}) decreased from 1371 to 1105 kA/m with increasing Ga concentration from 10.5 to 24.3 % at room temperature. The lattice parameter increased with the increase in Ga content because of the larger atomic radius of Ga atom than that of Fe. The increase in carrier density with Ga content caused in lower resistivity.

Duong Anh Tuan; Shin, Yooleemi; Cho, Sunglae [Department of Physics, University of Ulsan, Ulsan 680-749 (Korea, Republic of); Dang Duc Dung [Department of Physics, University of Ulsan, Ulsan 680-749 (Korea, Republic of); Department of General Physics, School of Engineering Physics, Ha Noi University of Science and Technology, 1 Dai Co Viet road, Ha Noi (Viet Nam); Vo Thanh Son [Centers for Nanobioenineering and Spintronics, Chungnam National University, Daejon 350-746 (Korea, Republic of)

2012-04-01T23:59:59.000Z

Index
Note: This page contains sample records for the topic "tn al ga" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
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Index
281

GaAs ohmic contacts for high temperature devices  

DOE Green Energy (OSTI)

Instrumentation requirements for geothermal wells, jet engines, and nuclear reactors have exceeded the high temperature capability of silicon devices. As one part of a program to develop high temperature compound semiconductor devices, four basic ohmic contact systems for n-type GaAs have been evaluated for contact resistance as a function of temperature (24 to 350/sup 0/C) and time (at 300/sup 0/C): Ni/AuGe; Ag/Si and Ag/Ni/Si; Al/Ge and Al/AlGe; and Au/Nb/Si and Pt/Nb/Si. Optimization of processing parameters produced viable high temperature contacts with all but the Al/Ge systems. Aging at 300/sup 0/C changed the contact resistivity in only the Ag/Ni/Si contacts. Film adhesion was excellent for the Al/Ge, Ni/AuGe, and Ag/Si systems as measured with ultrasonic Al wire bond pull strengths. Lower adhesion was noticed with Nb/Si systems measured with gold wire bond pull strengths.

Coquat, J.A.; Palmer, D.W.

1980-01-01T23:59:59.000Z

282

Polarized Emission from Single GaN Quantum Dots Grown by Molecular Beam Epitaxy  

Science Conference Proceedings (OSTI)

Polarization resolved microphotoluminescence measurements of single MBE-grown GaN/Al(Ga)N quantum dots (QDs) have been performed. The exciton and biexciton peaks with full width at half maximum as narrow as dots, resulting in different built-in electric field. Moreover, a strongly linearly polarized emission is observed for the investigated dots with a degree of linear polarization of about 0.9, interpreted as the valence-band mixing induced by in-plane anisotropy due to strain and/or QD shape.

Amloy, S. [Department of Physics, Chemistry, and Biology (IFM), Linkoeping University, S-58183 Linkoeping (Sweden); Department of Physics, Faculty of Science, Thaksin University, 93110 Phattalung (Thailand); Yu, K. H.; Karlsson, K. F.; Holtz, P. O. [Department of Physics, Chemistry, and Biology (IFM), Linkoeping University, S-58183 Linkoeping (Sweden); Farivar, R.; Andersson, T. G. [Applied Semiconductor Physics, Department of Microtechnology and Nanoscience, Chalmers University of Technology, S-41296 Goeteborg (Sweden)

2011-12-23T23:59:59.000Z

283

Room temperature green light emission from nonpolar cubic InGaN/GaN multi-quantum-wells  

E-Print Network (OSTI)

Room temperature green light emission from nonpolar cubic InGaN/GaN multi-quantum-wells Shunfeng Li Cubic InGaN/GaN multi-quantum-wells MQWs with high structural and optical quality are achieved by utilizing freestanding 3C-SiC 001 substrates and optimizing InGaN quantum well growth. Superlattice peaks up

As, Donat Josef

284

passivation of InGaN/GaN nanopillar light emitting diodes.  

E-Print Network (OSTI)

??Recently, InGaN/GaN based blue light emitting diodes (LEDs) have become widely available commercially, but their efficiency is reduced due to the quantum confined Stark effect… (more)

Choi, Won

2013-01-01T23:59:59.000Z

285

Detailed Analysis of Temperature Characteristics of InGaP/InGaAs ...  

Science Conference Proceedings (OSTI)

The current-voltage (I-V) characteristics of single-junction solar cells (InGaP, InGaAs, Ge solar cells) were measured at various temperatures. The structures of  ...

286

GA 30+-90 / GA 37-90 VSD: Oil-injected rotary screw ...  

U.S. Energy Information Administration (EIA)

GA 30+-90 / GA 37-90 VSD: Oil-injected rotary screw compressors, 30-90 kW / 40-125 hp,Kunshan CompAirs Machinery Plant Co.,Ltd is the leading air ...

287

GA 11+-30/GA 15-30 VSD: Oil-injected rotary screw compressors ...  

U.S. Energy Information Administration (EIA)

GA 11+-30/GA 15-30 VSD: Oil-injected rotary screw compressors, 11-30 kW / 15-40 hp,Kunshan CompAirs Machinery Plant Co.,Ltd is the leading air ...

288

GA 90+-160+ / GA 110-160 VSD: Oil-injected rotary screw ...  

U.S. Energy Information Administration (EIA)

GA 90+-160+ / GA 110-160 VSD: Oil-injected rotary screw compressors, 90-160 kW / 125-200 hp.,Kunshan CompAirs Machinery Plant Co.,Ltd is the leading ...

289

Quantized states in homogenous polarized GaInN GaN quantum wells  

E-Print Network (OSTI)

Quantized states in homogenous polarized GaInN GaN quantum wells C. Wetzel1, S. Kamiyama1, H. Amano wells is calculated in a single particle model. The act- ing electric eld in the wells and the band gap-dimensional well layers our approach is based on induction from results obtained at the binary GaN barri- ers

Wetzel, Christian M.

290

PIEZOELECTRIC LEVEL SPLITTING IN GaInN/GaN QUANTUM WELLS  

E-Print Network (OSTI)

PIEZOELECTRIC LEVEL SPLITTING IN GaInN/GaN QUANTUM WELLS C. Wetzel, T. Takeuchi, H. Amano, and IInN/GaN multiple quantum well samples in a large set of variable composition a clear correspondence of transitions in photo- and electroreflection, as well as photoluminescence is found. The effective band offset across

Wetzel, Christian M.

291

Spontaneous emission in GaN/InGaN photonic crystal nanopillars  

E-Print Network (OSTI)

. Sigalas, "InGaN/GaN quantum-well heterostructure light-emitting diodes employing photonic crystal, "III-nitride blue and ultraviolet photonic crystal light emitting diodes," Appl. Phys. Lett. 84, 466, and H. Benisty, "Photonic-crystal GaN light-emitting diodes with tailored guided modes distribution

Recanati, Catherine

292

Princeton Plasma Physics Lab - General Atomics (GA)  

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

general-atomics-ga General general-atomics-ga General Atomics en The Scorpion's Strategy: "Catch and Subdue" http://www.pppl.gov/node/1132

American Fusion News Category: 
ga">General Atomics (GA)
293

TMS P&GA Wired to Washington  

Science Conference Proceedings (OSTI)

P & GA COMMITTEE HOME ... the connection between MSE and such key U.S. initiatives as national security, energy independence, and economic growth.

294

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

295

Epitaxial Growth of GaN-based LEDs on Simple Sacrificial Substrates  

SciTech Connect

The objective of this project is to produce alternative substrate technologies for GaN-based LEDs by developing an ALD interlayer of Al{sub 2}O{sub 3} on sacrificial substrates such as ZnO and Si. A sacrificial substrate is used for device growth that can easily be removed using a wet chemical etchant leaving only the thin GaN epi-layer. After substrate removal, the GaN LED chip can then be mounted in several different ways to a metal heat sink/reflector and light extraction techniques can then be applied to the chip and compared for performance. Success in this work will lead to high efficiency LED devices with a simple low cost fabrication method and high product yield as stated by DOE goals for its solid state lighting portfolio.

Ian Ferguson; Chris Summers

2009-12-31T23:59:59.000Z

296

Structural Characterization of Doped GaSb Single Crystals by X-ray Topography  

Science Conference Proceedings (OSTI)

We characterized GaSb single crystals containing different dopants (Al, Cd and Te), grown by the Czochralski method, by x-ray topography and high angular resolution x-ray diffraction. Lang topography revealed dislocations parallel and perpendicular to the crystal's surface. Double-crystal GaSb 333 x-ray topography shows dislocations and vertical stripes than can be associated with circular growth bands. We compared our high-angular resolution x-ray diffraction measurements (rocking curves) with the findings predicted by the dynamical theory of x-ray diffraction. These measurements show that our GaSb single crystals have a relative variation in the lattice parameter ({Delta}d/d) on the order of 10{sup -5}. This means that they can be used as electronic devices (detectors, for example) and as x-ray monochromators.

Honnicke, M.G.; Mazzaro, I.; Manica, J.; Benine, E.; M da Costa, E.; Dedavid, B. A.; Cusatis, C.; Huang, X. R.

2009-09-13T23:59:59.000Z

297

Single-event dynamics of high-performance HBTs and GaAs MESFETs  

SciTech Connect

Picosecond charge-collection transients measured for GaAs/AlGaAs HBTs following 3.0 MeV [alpha]-particle and 620 nm picosecond laser excitation reveal charge-collection efficiencies up to twenty-eight times smaller than for GaAs MESFETs, with [approximately]90% of the charge collected within 75 ps of the ionizing event. The small charge-collection efficiency of the HBTs is a consequence of the ultrafast charge-collection dynamics in these devices. The authors show that picosecond laser excitation reproduces nicely the ion-induced transients, providing a valuable tool for the investigation of charge-collection and SEU phenomena in these devices.

McMorrow, D.; Melinger, J.S.; Campbell, A.B. (Naval Research Lab., Washington, DC (United States)); Weatherford, T.; Knudson, A.R.; Tran, L.H.

1993-12-01T23:59:59.000Z

298

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

299

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

300

Radiation-induced surface degradation of GaAs and high electron mobility transistor structures  

Science Conference Proceedings (OSTI)

Transistor heterostructures with high-carrier-mobility have been studied. It is shown that, as the {gamma}-irradiation dose {Phi} increases, their degradation occurs in the following sequence. (i) At {Phi} 0.2-eV decrease in the diffusion energy of intrinsic defects and, probably, atmospheric oxygen. (ii) At {Phi} > 10{sup 7} rad, highly structurally disordered regions larger than 1 {mu}m are formed near microscopic defects or dislocations. (iii) At {Phi} > 10{sup 8} rad, there occurs degradation of the internal AlGaAs/InGaAs/GaAs interfaces and the working channel. An effective method for studying the degradation processes in heterostructures is to employ a set of structural diagnostic methods to analyze processes of radiation-induced and aging degradation, in combination with theoretical simulation of the occurring processes.

Bobyl, A. V.; Konnikov, S. G.; Ustinov, V. M.; Baidakova, M. V.; Maleev, N. A.; Sakseev, D. A. [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation); Konakova, R. V., E-mail: konakova@isp.kiev.ua; Milenin, V. V.; Prokopenko, I. V. [National Academy of Sciences of Ukraine, Lashkaryov Institute of Semiconductor Physics (Ukraine)

2012-06-15T23:59:59.000Z

Note: This page contains sample records for the topic "tn al ga" 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

ALS Chemistry Lab  

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

ALS Chemistry Lab Print ALS Chemistry Labs The ALS Chemistry Labs are located in the User Support Building (15-130) and in Building 6 (6-2233)*. These spaces are dedicated for...

302

ALS superbend magnet system  

E-Print Network (OSTI)

ALS Superbend Magnet System J. Zbasnik † , S. T. Wang †† ,of a High-Field Magnet for the ALS,” Transactions AppliedRefrigeration options for the ALS Superbend dipole magnets”,

2000-01-01T23:59:59.000Z

303

Access to the ALS  

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

Gate Access Access to the ALS Print User Access The ALS experiment floor (Building 6) is a Controlled Access Area for radiation protection. All ALS users are required to register...

304

ALS Longitudinal Kicker  

E-Print Network (OSTI)

be published in the Proceedings ALS Longitudinal Kickers F.IJ3Ir-33088 lE93 005961 ALS Longitudinul Kickers* F. VoelkerContract No. DE-AC03-76SFOOO98. ALS LONGITUDINAL KICKERS F.

Voelkner, F.

2011-01-01T23:59:59.000Z

305

ALS superbend magnet performance  

E-Print Network (OSTI)

ALS Superbend Magnet Performance S. Marks, J. Zbasnik, W.the Advanced Light Source (ALS), with the fourth magnet as ahe Advanced Light Source (ALS) at the Lawrence Berkeley

2001-01-01T23:59:59.000Z

306

Price of Elba Island, GA Liquefied Natural Gas Total Imports...  

Annual Energy Outlook 2012 (EIA)

Elba Island, GA Liquefied Natural Gas Total Imports (Dollars per Thousand Cubic Feet) Price of Elba Island, GA Liquefied Natural Gas Total Imports (Dollars per Thousand Cubic Feet)...

307

2012 ALS User Meeting  

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

2012 ALS User Meeting 2012 ALS User Meeting Print Tuesday, 14 June 2011 12:37 user meeting web banner Home Agenda Awards Exhibitors Lodging Posters Registration Transportation...

308

ALS Users' Association Charter  

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

organized framework for the interaction between those who use the Advanced Light Source (ALS) at the Lawrence Berkeley Laboratory (LBL) for their research and the ALS management,...

309

ALS Beamlines Directory  

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

Parameters, Contact Information, and Schedules Download a high-resolution version of the ALS Beamclock. See Beamclock to view the ALS energy-related beamlines beamclock. Beamline...

310

Al,N  

Science Conference Proceedings (OSTI)

Presentation Title, Significantly Bandgap-reduced and Enhanced PEC Response of Al and N Co-doped ZnO:(Al,N) Films for Solar Driven Hydrogen Production.

311

GaInP/GaAs/GaInAs Monolithic Tandem Cells for High-Performance Solar Concentrators  

DOE Green Energy (OSTI)

We present a new approach for ultra-high-performance tandem solar cells that involves inverted epitaxial growth and ultra-thin device processing. The additional degree of freedom afforded by the inverted design allows the monolithic integration of high-, and medium-bandgap, lattice-matched (LM) subcell materials with lower-bandgap, lattice-mismatched (LMM) materials in a tandem structure through the use of transparent compositionally graded layers. The current work concerns an inverted, series-connected, triple-bandgap, GaInP (LM, 1.87 eV)/GaAs (LM, 1.42 eV)/GaInAs (LMM, {approx}1 eV) device structure grown on a GaAs substrate. Ultra-thin tandem devices are fabricated by mounting the epiwafers to pre-metallized Si wafer handles and selectively removing the parent GaAs substrate. The resulting handle-mounted, ultra-thin tandem cells have a number of important advantages, including improved performance and potential reclamation/reuse of the parent substrate for epitaxial growth. Additionally, realistic performance modeling calculations suggest that terrestrial concentrator efficiencies in the range of 40-45% are possible with this new tandem cell approach. A laboratory-scale (0.24 cm2), prototype GaInP/GaAs/GaInAs tandem cell with a terrestrial concentrator efficiency of 37.9% at a low concentration ratio (10.1 suns) is described, which surpasses the previous world efficiency record of 37.3%.

Wanlass, M. W.; Ahrenkiel, S. P.; Albin, D. S.; Carapella, J. J.; Duda, A.; Emery, K.; Geisz, J. F.; Jones, K.; Kurtz, S.; Moriarty, T.; Romero, M. J.

2005-08-01T23:59:59.000Z

312

Ohmic contacts to Si-implanted and un-implanted n-type GaN  

SciTech Connect

We report on ohmic contacts to Si-implanted and un-implanted n-type GaN on sapphire. A ring shaped contact design avoids the need to isolate the contact structures by additional implantation or etching. Metal layers of Al and Ti/Al were investigated. On un-implanted GaN, post metalization annealing was performed in an RTA for 30 seconds in N{sub 2} at 700, 800, and 900 C. A minimum specific contact resistance (r{sub c}) of 1.4{times}10{sup -5} {Omega}{minus}cm{sup 2} was measured for Ti/Al at an annealing temperature of 800 C. Although these values are reasonably low, variations of 95% in specific contact resistance were measured within a 500 {mu}m distance on the wafer. These results are most likely caused by the presence of compensating hydrogen. Specific contact resistance variation was reduced from 95 to 10% by annealing at 900 C prior to metalization. On Si-implanted GaN, un-annealed ohmic contacts were formed with Ti/Al metalization. The implant activation anneal of 1120 C generates nitrogen vacancies that leave the surface heavily n-type, which makes un-annealed ohmic contacts with low contact resistivity possible.

Brown, J; Ramer, J.; Zheng, L.F.; Hersee, S.D. [New Mexico Univ., Albuquerque, NM (United States). Center for High Technology Materials; Zolper, J. [Sandia National Labs., Albuquerque, NM (United States)

1996-02-01T23:59:59.000Z

313

US SoAtl GA Site Consumption  

Gasoline and Diesel Fuel Update (EIA)

GA GA Site Consumption million Btu $0 $500 $1,000 $1,500 $2,000 $2,500 US SoAtl GA Expenditures dollars ALL ENERGY average per household (excl. transportation) 0 4,000 8,000 12,000 16,000 US SoAtl GA Site Consumption kilowatthours $0 $300 $600 $900 $1,200 $1,500 $1,800 US SoAtl GA Expenditures dollars ELECTRICITY ONLY average per household * Site energy consumption (89.5 million Btu) and energy expenditures per household ($2,067) in Georgia are similar to the U.S. household averages. * Per household electricity consumption in Georgia is among the highest in the country, but similar to other states in the South. * Forty-five percent of homes in Georgia were built since 1990, a characteristic typically associated with lower per household consumption. Georgia homes,

314

US SoAtl GA Site Consumption  

U.S. Energy Information Administration (EIA) Indexed Site

GA GA Site Consumption million Btu $0 $500 $1,000 $1,500 $2,000 $2,500 US SoAtl GA Expenditures dollars ALL ENERGY average per household (excl. transportation) 0 4,000 8,000 12,000 16,000 US SoAtl GA Site Consumption kilowatthours $0 $300 $600 $900 $1,200 $1,500 $1,800 US SoAtl GA Expenditures dollars ELECTRICITY ONLY average per household * Site energy consumption (89.5 million Btu) and energy expenditures per household ($2,067) in Georgia are similar to the U.S. household averages. * Per household electricity consumption in Georgia is among the highest in the country, but similar to other states in the South. * Forty-five percent of homes in Georgia were built since 1990, a characteristic typically associated with lower per household consumption. Georgia homes,

315

Characterization of high-quality InGaN/GaN multiquantum wells with time-resolved photoluminescence  

E-Print Network (OSTI)

Characterization of high-quality InGaN/GaN multiquantum wells with time-resolved photoluminescence October 1997; accepted for publication 5 January 1998 Recombination in single quantum well and multiquantum well InGaN/GaN structures is studied using time-resolved photoluminescence and pulsed

Bowers, John

316

Journal of Crystal Growth 298 (2007) 272275 Dislocation analysis in homoepitaxial GaInN/GaN light emitting  

E-Print Network (OSTI)

of GaInN/GaN-based light emitting diodes (LED) on quasi-bulk GaN with an atomically flat polished were much improved. The optical output power of the light emitting diode increased by more than one. Cathodoluminescence; A1. Threading dislocation density; A2. Homoepitaxial growth; B1. GaInN; B3. Light emitting diode

Wetzel, Christian M.

317

Discrete Steps in the Capacitance-Voltage Characteristics of GaInN/GaN Light Emitting Diode Structures  

E-Print Network (OSTI)

Discrete Steps in the Capacitance-Voltage Characteristics of GaInN/GaN Light Emitting Diode and GaInN/GaN heterostructures typically used for high efficiency light emitting diodes is of high materials for green, blue, and UV light emitting diodes (LED) [1-2]. It is known that huge piezoelectric

Wetzel, Christian M.

318

J1, MBE Growth of Metamorphic InGaP on GaAs and GaP for Wide ...  

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 ...

319

GA Solar | Open Energy Information  

Open Energy Info (EERE)

Solar Solar Jump to: navigation, search Name GA-Solar Place Madrid, Spain Zip 28045 Sector Solar Product Madrid based solar project developer, owned by Spanish industrial group Corporacion Gestamp. Coordinates 40.4203°, -3.705774° 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":40.4203,"lon":-3.705774,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

320

ALS Chemistry Lab  

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

Chemistry Lab Print ALS Chemistry Labs The ALS Chemistry Labs are located in the User Support Building (15-130) and in Building 6 (6-2233)*. These spaces are dedicated for...

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


321

ALS Staff Photo  

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

ALS Staff Photo Print On May 14, 2013, members of ALS staff posed for a group photo in front of the dome. A hi-res version can be downloaded here. The last staff photo was taken in...

322

ALS User Meeting  

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

ALS User Meeting Print Due to the current lapse of federal funding, Berkeley Lab Web sites, including ALS sites, are accessible, but may not be updated until Congress approves...

323

ALS User Meeting  

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

User Meeting ALS User Meeting Print Tuesday, 14 June 2011 12:37 Due to the current lapse of federal funding, Berkeley Lab Web sites, including ALS sites, are accessible, but may...

324

ALS User Meeting Archives  

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

ALS User Meeting Archives ALS User Meeting Archives Print Monday, 06 June 2011 09:25 Past User Meeting Agendas, Workshops, and Awards Year Agenda Workshops David A. Shirley...

325

111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111 us 20060200344Al  

E-Print Network (OSTI)

20060200344Al (19) United States (12) Patent Application Publication Kosek et al. (10) Pub. No.: US 2006) Inventors: Daniel A. Kosek, Missoula, MT (US); Robert Crawford Maher, Bozeman, MT (US) A method of reducing

Maher, Robert C.

326

Plasma Damage in p-GaN  

SciTech Connect

The effect of Inductively Coupled Plasma H{sub 2} or Ar discharges on the breakdown voltage of p-GaN diodes was measured over a range of ion energies and fluxes. The main effect of plasma exposure is a decrease in net acceptor concentration to depths of 400-550{angstrom}. At high ion fluxes or energies there can be type conversion of the initially p-GaN surface. Post etch annealing at 900 C restores the initial conductivity.

Cao, X.A.; Dang, G.T.; Hickman, R.A.; Pearton, S.J.; Ren, F.; Shul, R.J.; Van Hove, J.M.; Zhang, A.P.; Zhang, L.

1999-06-30T23:59:59.000Z

327

GaTe semiconductor for radiation detection  

SciTech Connect

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

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

2009-06-23T23:59:59.000Z

328

GaN directional couplers for integrated quantum photonics  

SciTech Connect

Large cross-section GaN waveguides are proposed as a suitable architecture to achieve integrated quantum photonic circuits. Directional couplers with this geometry have been designed with aid of the beam propagation method and fabricated using inductively coupled plasma etching. Scanning electron microscopy inspection shows high quality facets for end coupling and a well defined gap between rib pairs in the coupling region. Optical characterization at 800 nm shows single-mode operation and coupling-length-dependent splitting ratios. Two photon interference of degenerate photon pairs has been observed in the directional coupler by measurement of the Hong-Ou-Mandel dip [C. K. Hong, et al., Phys. Rev. Lett. 59, 2044 (1987)] with 96% visibility.

Zhang Yanfeng; McKnight, Loyd; Watson, Ian M.; Gu, Erdan; Calvez, Stephane; Dawson, Martin D. [Institute of Photonics, SUPA, University of Strathclyde, Glasgow G4 0NW (United Kingdom); Engin, Erman; Cryan, Martin J.; Thompson, Mark G.; O'Brien, Jeremy L. [Centre for Quantum Photonics, H. H. Wills Physics Laboratory and Department of Electrical and Electronic Engineering, University of Bristol, Merchant Venturers Building, Woodland Road, Bristol BS8 1UB (United Kingdom)

2011-10-17T23:59:59.000Z

329

Growth of cubic GaN quantum dots  

SciTech Connect

Zinc-blende GaN quantum dots were grown on 3C-AlN(001) by two different methods in a molecular beam epitaxy system. The quantum dots in method A were fabricated by the Stranski-Krastanov growth process. The quantum dots in method B were fabricated by droplet epitaxy, a vapor-liquid-solid process. The density of the quantum dots was controllable in a range of 10{sup 8} cm{sup -2} to 10{sup 12} cm{sup -2}. Reflection high energy electron diffraction analysis confirmed the zinc-blende crystal structure of the QDs. Photoluminescence spectroscopy revealed the optical activity of the QDs, the emission energy was in agreement with the exciton ground state transition energy of theoretical calculations.

Schupp, T.; Lischka, K.; As, D. J. [Universitaet Paderborn, Department Physik, Warburger Str.100, 33095 Paderborn (Germany); Meisch, T.; Neuschl, B.; Feneberg, M.; Thonke, K. [Institut fuer Quantenmaterie, Universitaet Ulm, 89069 Ulm (Germany)

2010-11-01T23:59:59.000Z

330

Plasma Enhanced ALD of High-k Dielectrics on GaN and AlGaN  

Science Conference Proceedings (OSTI)

Recent efforts to improve performance of high power devices have focused on the ... Characterization of Degradation for MLCC under Thermal and Electrical ...

331

Scanning capacitance microscopy of AlGaN/GaN heterostructure field-effect transistor epitaxial layer structures  

E-Print Network (OSTI)

, University of California, San Diego, La Jolla, California, 92093-0407 J. M. Redwing and K. S. Boutros ATMI

Yu, Edward T.

332

SnO2 functionalized AlGaN/GaN high electron mobility transistor for hydrogen sensing applications  

E-Print Network (OSTI)

. Nanocrystalline indium oxide-doped tin oxide thin film as low temperature hydrogen sensor. Sensors and Actuators B Available online 1 May 2012 Keywords: Hydrogen sensor High electron mobility transistors (HEMT) Tin oxide rights reserved. 1. Introduction Hydrogen is a clean, renewable, and sustainable energy carrier

Florida, University of

333

An accurate polynomial-based analytical charge control model for AlGaN/GaN HEMT  

Science Conference Proceedings (OSTI)

A new nonlinear expression of Fermi-level variation with two-dimensional electron gas density in a high electron mobility has been proposed. It was found that our expression has a better fit with the numerical results. And, an analytical expression for n{sub s} in terms of the applied gate voltage is developed. Comparing with other previous approximations, the solutions of our expression has a better agreement with the exact numerical results over the entire range of interest. Besides, the solutions of our expression of n{sub s} versus V{sub G} are compared with the experimental data and shown to be in good agreement over a wide range of bias conditions.

Pu Jinrong; Sun Jiuxun, E-mail: sjx@uestc.edu.cn; Zhang Da [University of Electronic Science and Technology of China, Department of Applied Physics (China)

2011-09-15T23:59:59.000Z

334

Nanocrystals cylindrical microcavities exploiting thin-walled InGaAs/GaAs microtubes  

Science Conference Proceedings (OSTI)

This paper relies on the design and fabrication of CdSe/ZnS core/shell colloidal nanocrystals (NCs) cylindrical microcavities for microphotonics applications. The fabrication technology relies on the release of the strain in strained heterostructures, ... Keywords: Colloidal nanocrystals, InGaAs/GaAs microtubes, Strained multilayer

C. Giordano; M. T. Todaro; A. Salhi; L. Martiradonna; I. Viola; A. Passabí; L. Carbone; G. Gigli; A. Passaseo; M. De Vittorio

2007-05-01T23:59:59.000Z

335

Murdock Road Knoxville.TN  

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

or licensing to companies and partners outside the United States). Given the size and financial strength of the U.S. marketplace, I believe the ultimate licensee of this...

336

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

the Electrochemical Solution the Electrochemical Solution Growth (ESG) Technique for Native GaN Substrates DOE Energy Storage & Power Electronics Research Program 30 September 2008 PI: Karen Waldrip Advanced Power Sources R&D, Dept 2546 PM: Stan Atcitty, John Boyes Sandia National Laboratories, Albuquerque, NM, 87185 Sponsor: Gil Bindewald, DOE Power Electronics & Energy Storage Program 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. Outline * Motivation * Existing GaN Growth Technique - Epitaxial Lateral Overgrowth - Methods for Growing Bulk GaN * Development of the Electrochemical Solution Growth Technique

337

ALS User Meeting Archives  

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

and Mike Scheinfein (Arizona State University) for development of the PEEM2 photoemission electron microscope. to the members of the ALS User Services Office (Ruth Pepe, Bernie...

338

ALS Postdoctoral Fellowship Program  

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

x-ray radiation for scientific and technological research. As the world's first third-generation synchrotron radiation source, the ALS offers outstanding performance in the...

339

ALS Postdoctoral Fellowship Highlights  

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

Postdoctoral Fellowship Highlights Print Since its inception in 2005, the ALS Postdoctoral Fellowship program has supported young scientists in new and ongoing research projects at...

340

Howes et al. Reply  

E-Print Network (OSTI)

Howes et al. Reply to Comment on "Kinetic Simulations of Magnetized Turbulence in Astrophysical Plasmas" arXiv:0711.4355

Howes, G G; Dorland, W; Hammett, G W; Quataert, E; Schekochihin, A A; Tatsuno, T; 10.1103/PhysRevLett.101.149502

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "tn al ga" 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

ALS Users' Association Charter  

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

Users' Executive Committee ALS Users' Association Charter Print The purpose of the Advanced Light Source Users' Association (ALSUA) is to provide an organized framework for the...

342

GaN Nanopore Arrays: Fabrication and Characterization  

E-Print Network (OSTI)

GaN nanopore arrays with pore diameters of approximately 75 nm were fabricated by inductively coupled plasma etching (ICP) using anodic aluminum oxide (AAO) films as etch masks. Nanoporous AAO films were formed on the GaN ...

Wang, Yadong

343

Study of high quality indium nitride films grown on Si(100) substrate by RF-MOMBE with GZO and AlN buffer layers  

Science Conference Proceedings (OSTI)

Wurtzite structure InN films were prepared on Si(100) substrates using radio-frequency metal-organic molecular beam epitaxy (RF-MOMBE) system. Ga-doped ZnO (GZO) and Amorphous AlN (a-AlN) film were used as buffer layers for InN films growth. Structural, ...

Wei-Chun Chen, Shou-Yi Kuo

2012-01-01T23:59:59.000Z

344

Magnetoelastic Coupling in NiMnGa Ferromagnetic Shape ...  

Science Conference Proceedings (OSTI)

... Magnetoelastic Coupling in NiMnGa Ferromagnetic Shape Memory Alloys. Peng Zhao (Dept. of Materials Science and ...

345

Science DMZ for ALS  

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

ALS ALS About ESnet Overview ESnet Staff Governance Our Network Case Studies OSCARS Case Studies Science DMZ Case Studies Science DMZ CU Science DMZ Penn State & VTTI Science DMZ NOAA Science DMZ NERSC Science DMZ ALS Multi-facility Workflow LCLS ESnet Strategic Plan ESnet Organizational Chart ESnet History Science Requirements Careers Contact Us Technical Assistance: 1 800-33-ESnet (Inside the US) 1 800-333-7638 (Inside the US) 1 510-486-7600 (Globally) 1 510-486-7607 (Globally) Report Network Problems: trouble@es.net Provide Web Site Feedback: info@es.net Science DMZ for ALS Many beamline scientists at Berkeley Lab's Advanced Light Source (ALS) are or will be experiencing slower network speeds because of instrument upgrades. These new instruments, or more specifically detectors, are

346

Lattice constant grading in the Al.sub.y Ca.sub.1-y As.sub.1-x Sb.sub.x alloy system  

DOE Patents (OSTI)

Liquid phase epitaxy is employed to grow a lattice matched layer of GaAsSb on GaAs substrates through the compositional intermediary of the III-V alloy system AlGaAsSb which acts as a grading layer. The Al constituent reaches a peak atomic concentration of about 6% within the first 2.5.mu.m of the transition layer, then decreases smoothly to about 1% to obtain a lattice constant of 5.74 A. In the same interval the equilibrium concentration of Sb smoothly increases from 0 to about 9 atomic percent to form a surface on which a GaAsSb layer having the desired energy bandgap of 1.1 ev for one junction of an optimized dual junction photovoltaic device. The liquid phase epitaxy is accomplished with a step cooling procedure whereby dislocation defects are more uniformly distributed over the surface of the growing layer.

Moon, Ronald L. (Palo Alto, CA)

1981-01-01T23:59:59.000Z

347

GaAs photoconductive semiconductor switch  

DOE Patents (OSTI)

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

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

1998-01-01T23:59:59.000Z

348

GaN: Defect and Device Issues  

SciTech Connect

The role of extended and point defects, and key impurities such as C, O and H, on the electrical and optical properties of GaN is reviewed. Recent progress in the development of high reliability contacts, thermal processing, dry and wet etching techniques, implantation doping and isolation and gate insulator technology is detailed. Finally, the performance of GaN-based electronic and photonic devices such as field effect transistors, UV detectors, laser diodes and light-emitting diodes is covered, along with the influence of process-induced or grown-in defects and impurities on the device physics.

Pearton, S.J.; Ren, F.; Shul, R.J.; Zolper, J.C.

1998-11-09T23:59:59.000Z

349

A New Combustion Synthesis Method for GaN:Eu3+ and Ga2O3 :Eu3+  

E-Print Network (OSTI)

A New Combustion Synthesis Method for GaN:Eu3+ and Ga2O3 :Eu3+ Luminescent Powders G. A. Hirata1 between the precursors. The preparation of Eu-doped Ga2O3 powders was achieved using a new combustion)3 and Ga(NO3)3 as the precursors and hydrazine as (non-carbonaceous) fuel. A spontaneous combustion

McKittrick, Joanna

350

K1, Molecular Beam Epitaxy of Catalyst-Free InGaN/GaN Nanowires ...  

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 ...

351

JJ2, Optical Polarization of Non-Polar GaInN/GaN LEDs  

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 ...

352

Temperature dependence of the dielectric response of AlSb  

SciTech Connect

Spectroscopic ellipometry was used to determine the optical response of an intrinsic AlSb film as a function of temperature. The 1.5 {mu}m thick film was grown on a (001) GaAs substrate by molecular beam epitaxy. Measurements were done at temperatures from 300 K to the growth temperature of 800 K over a spectral range of 0.7 to 5.0 eV. To avoid oxidation artifacts, measurements were done with the film in situ. The data were analyzed using a parametric semiconductor model for its temperature dependence.

Jung, Y. W.; Kim, T. J.; Kim, Y. D. [Nano-Optical Property Laboratory and Department of Physics, Kyung Hee University, Seoul (Korea, Republic of); Shin, S. H.; Kim, S. Y.; Song, J. D. [Center for Spintronics Research, Korea Institute of Science and Technology, Seoul (Korea, Republic of)

2011-12-23T23:59:59.000Z

353

ALS Beamlines Directory  

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

ALS Beamlines Directory Print ALS Beamlines Directory Print Beamlines, Parameters, Contact Information, and Schedules Download a high-resolution version of the ALS Beamclock. See Beamclock to view the ALS energy-related beamlines beamclock. Beamline Parameters Beamline and endstation technical information is available through the links below. Unless otherwise noted, all beamlines are currently operational. Individual beamline schedules are posted when available. Please contact the responsible beamline scientist for additional schedule information. When calling from off-site, all beamline (BL) phone numbers that begin with a "2" are preceded by 495- (i.e., 495-2014); all others are preceded by 486-. Beamline Number Source Technique/ Group Name Energy Range Beamline Contact Schedule/BL Phone

354

ALS Beamlines Directory  

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

ALS Beamlines Directory Print ALS Beamlines Directory Print Beamlines, Parameters, Contact Information, and Schedules Download a high-resolution version of the ALS Beamclock. See Beamclock to view the ALS energy-related beamlines beamclock. Beamline Parameters Beamline and endstation technical information is available through the links below. Unless otherwise noted, all beamlines are currently operational. Individual beamline schedules are posted when available. Please contact the responsible beamline scientist for additional schedule information. When calling from off-site, all beamline (BL) phone numbers that begin with a "2" are preceded by 495- (i.e., 495-2014); all others are preceded by 486-. Beamline Number Source Technique/ Group Name Energy Range Beamline Contact Schedule/BL Phone

355

ALS User Meeting Archives  

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

ALS User Meeting Archives ALS User Meeting Archives Past User Meeting Agendas, Workshops, and Awards Year Agenda Workshops David A. Shirley (Science) Klaus Halbach (Instrumentation) Tim Renner (Service) 2012 2012 User Meeting Agenda 2012 User Meeting Workshops 2012 ALS User Meeting Awards Carl Percival, Dudley Shallcross, Craig Taatjes and David Osborn (Sandia), for making the first direct measurements of the reactions of Criegee intermediates, and showing that their impact on tropospheric chemistry and climate may be substantially greater than previously assumed. 2012 ALS User Meeting Awards Jeff Dickert and Simon Morton of Berkeley Lab's Physical Biosciences Division for the invention and implementation of the Compact Variable Collimator (CVC), which has led to a dramatic increase in productivity of protein crystallography.

356

2012 ALS Open House  

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

House 2012 ALS Open House Print More than 6000 people came up the hill to see what is happening at Berkeley Lab during Open House on Saturday, October 13, and more than 1500 of...

357

ALS User Meeting  

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

Print Due to the current lapse of federal funding, Berkeley Lab Web sites, including ALS sites, are accessible, but may not be updated until Congress approves funds for Fiscal...

358

SAS Output  

U.S. Energy Information Administration (EIA) Indexed Site

Coal Consumers in the Manufacturing and Coke Sectors, 2012" Coal Consumers in the Manufacturing and Coke Sectors, 2012" "Company Name","Plant Location" "Top Ten Manufacturers" "American Crystal Sugar Co","MN, ND" "Archer Daniels Midland","IA, IL, MN, ND, NE" "Carmeuse Lime Stone Inc","AL, IL, IN, KY, MI, OH, PA, TN, VA, WI" "Cemex Inc","AL, CA, CO, FL, GA, KY, OH, TN, TX" "Dakota Gasification Company","ND" "Eastman Chemical Company","TN" "Georgia-Pacific LLC","AL, GA, OK, VA, WI" "Holcim (US) Inc","AL, CO, MD, MO, MT, OK, SC, TX, UT" "NewPage Corporation","MD, MI, WI" "U S Steel Corporation","AL, IN, MI, MN"

359

U.S. Energy Information Administration | Annual Coal Report 2012  

U.S. Energy Information Administration (EIA) Indexed Site

Coal Consumers in the Manufacturing and Coke Sectors, 2012 Coal Consumers in the Manufacturing and Coke Sectors, 2012 U.S. Energy Information Administration | Annual Coal Report 2012 Table 25. Coal Consumers in the Manufacturing and Coke Sectors, 2012 U.S. Energy Information Administration | Annual Coal Report 2012 Company Name Plant Location Top Ten Manufacturers American Crystal Sugar Co MN, ND Archer Daniels Midland IA, IL, MN, ND, NE Carmeuse Lime Stone Inc AL, IL, IN, KY, MI, OH, PA, TN, VA, WI Cemex Inc AL, CA, CO, FL, GA, KY, OH, TN, TX Dakota Gasification Company ND Eastman Chemical Company TN Georgia-Pacific LLC AL, GA, OK, VA, WI Holcim (US) Inc AL, CO, MD, MO, MT, OK, SC, TX, UT NewPage Corporation MD, MI, WI U S Steel Corporation AL, IN, MI, MN Other Major Manufacturers Ash Grove Cement Co

360

Guided Neuronal Growth on Arrays of Biofunctionalized GaAs/InGaAs Semiconductor Microtubes  

E-Print Network (OSTI)

We demonstrate embedded growth of cortical mouse neurons in dense arrays of semiconductor microtubes. The microtubes, fabricated from a strained GaAs/InGaAs heterostructure, guide axon growth through them and enable electrical and optical probing of propagating action potentials. The coaxial nature of the microtubes -- similar to myelin -- is expected to enhance the signal transduction along the axon. We present a technique of suppressing arsenic toxicity and prove the success of this technique by overgrowing neuronal mouse cells.

Cornelius S. Bausch; Aune Koitmäe; Eric Stava; Amanda Price; Pedro J. Resto; Yu Huang; David Sonnenberg; Yuliya Stark; Christian Heyn; Justin C. Williams; Erik W. Dent; Robert H. Blick

2013-05-06T23:59:59.000Z

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


361

Recent progress in InGaAsSb/GaSb TPV devices  

DOE Green Energy (OSTI)

AstroPower is developing InGaAsSb thermophotovoltaic (TPV) devices. This photovoltaic cell is a two-layer epitaxial InGaAsSb structure formed by liquid-phase epitaxy on a GaSb substrate. The (direct) bandgap of the In{sub 1{minus}x}Ga{sub x}As{sub 1{minus}y}Sb{sub y} alloy is 0.50 to 0.55 eV, depending on its exact alloy composition (x,y); and is closely lattice-matched to the GaSb substrate. The use of the quaternary alloy, as opposed to a ternary alloy--such as, for example InGaAs/InP--permits low bandgap devices optimized for 1,000 to 1,500 C thermal sources with, at the same time, near-exact lattice matching to the GaSb substrate. Lattice matching is important since even a small degree of lattice mismatch degrades device performance and reliability and increases processing complexity. Internal quantum efficiencies as high as 95% have been measured at a wavelength of 2 microns. At 1 micron wavelengths, internal quantum efficiencies of 55% have been observed. The open-circuit voltage at currents of 0.3 A/cm{sup 2} is 0.220 volts and 0.280 V for current densities of 2 A/cm{sup 2}. Fill factors of 56% have been measured at 60 mA/cm{sup 2}. However, as current density increases there is some decrease in fill factor. The results to date show that the GaSb-based quaternary compounds provide a viable and high performance energy conversion solution for thermophotovoltaic systems operating with 1,000 to 1,500 C source temperatures.

Shellenbarger, Z.A.; Mauk, M.G.; DiNetta, L.C. [AstroPower, Inc., Newark, DE (United States); Charache, G.W. [Lockheed Martin Corp., Schenectady, NY (United States)

1996-05-01T23:59:59.000Z

362

GaNPAs Solar Cells Lattice-Matched To GaP: Preprint  

DOE Green Energy (OSTI)

This conference paper describes the III-V semiconductors grown on silicon substrates are very attractive for lower-cost, high-efficiency multijunction solar cells, but lattice-mismatched alloys that result in high dislocation densities have been unable to achieve satisfactory performance. GaNxP1-x-yAsy is a direct-gap III-V alloy that can be grown lattice-matched to Si when y= 4.7x - 0.1. We propose the use of lattice-matched GaNPAs on silicon for high-efficiency multijunction solar cells. We have grown GaNxP1-x-yAsy on GaP (with a similar lattice constant to silicon) by metal-organic chemical vapor phase epitaxy with direct band-gaps in the range of 1.5 to 2.0 eV. We demonstrate the performance of single-junction GaNxP1-x-yAsy solar cells grown on GaP substrates and discuss the prospects for the development of monolithic high-efficiency multijunction solar cells based on silicon substrates.

Geisz, J. F.; Friedman, D. J.; Kurtz, S.

2002-05-01T23:59:59.000Z

363

Synthesis and Mechanical Properties of AL/ ?-Al12Mg17 ...  

Science Conference Proceedings (OSTI)

Symposium, Advances in Mechanics of One-Dimensional Micro/Nano Materials. Presentation Title, Synthesis and Mechanical Properties of AL/ ?-Al12Mg17 ...

364

Data Management at the ALS  

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

Data Management at the ALS Print Users of the ALS are responsible for meeting their data management obligations to their home institutions and granting agencies. The ALS does not...

365

ALS in the News  

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

feed-image feed-image Digg: ALSBerkeleyLab Facebook Page: 208064938929 Flickr: advancedlightsource Twitter: ALSBerkeleyLab YouTube: AdvancedLightSource Home About the ALS ALS in the News ALS in the News Roman Seawater Concrete Holds the Secret to Cutting Carbon Emissions Print Tuesday, 04 June 2013 00:00 An international team led by Paulo Monteiro of the Advanced Light Source and UC Berkeley has analyzed samples of Roman concrete from harbor installations that have survived 2,000 years of chemical attack and wave action, "one of the most durable construction materials on the planet," says UC Berkeley's Marie Jackson, a leading member of the team. Says Monteiro, "It's not that modern concrete isn't good, but manufacturing Portland cement accounts for seven percent of the carbon dioxide that industry puts into the air." The carbon footprint of Roman concrete, made from lime, volcanic ash, and seawater, is much smaller.

366

ALS Beamlines Directory  

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

Beamlines Directory Beamlines Directory ALS Beamlines Directory Print Beamlines, Parameters, Contact Information, and Schedules Download a high-resolution version of the ALS Beamclock. See Beamclock to view the ALS energy-related beamlines beamclock. Beamline Parameters Beamline and endstation technical information is available through the links below. Unless otherwise noted, all beamlines are currently operational. Individual beamline schedules are posted when available. Please contact the responsible beamline scientist for additional schedule information. When calling from off-site, all beamline (BL) phone numbers that begin with a "2" are preceded by 495- (i.e., 495-2014); all others are preceded by 486-. Beamline Number Source Technique/ Group Name Energy Range Beamline Contact Schedule/BL Phone

367

Al-Zr (Aluminum - Zirconium)  

Science Conference Proceedings (OSTI)

Al-Zr crystallographic data...6 3 / mcm ZrAl 22.8 oC 8 Cmcm Zr 2 Al 3 31 oF 40 Fdd 2 ZrAl 2 37.2 hP 12 P 6 3 / mmc ZrAl 3 47 tI 16 I 4/ mmm (Al) 99.86 to 100 cF 4 Fm m...

368

Electronic properties and deep traps in electron-irradiated n-GaN  

Science Conference Proceedings (OSTI)

The study is concerned with the effect of electron irradiation (with the energies E = 7 and 10 MeV and doses D = 10{sup 16}-10{sup 18} cm{sup -2}) and subsequent heat treatments in the temperature range 100-1000 Degree-Sign C on the electrical properties and the spectrum of deep traps of undoped (concentration of electrons n = 1 Multiplication-Sign 10{sup 14}-1 Multiplication-Sign 10{sup 16} cm{sup -3}), moderately Si-doped (n = (1.2-2) Multiplication-Sign 10{sup 17} cm{sup -3}), and heavily Si-doped (n = (2-3.5) Multiplication-Sign 10{sup 18} cm{sup -3}) epitaxial n-GaN layers grown on Al{sub 2}O{sub 3} substrates by metal-organic chemical vapor deposition. It is found that, on electron irradiation, the resistivity of n-GaN increases, this is due to a shift of the Fermi level to the limiting position close to E{sub c} -0.91 eV. The spectrum of deep traps is studied for the initial and electron-irradiated n-GaN. It is shown that the initial properties of the irradiated material are restored in the temperature range 100-1000 Degree-Sign C, with the main stage of the annealing of radiation defects at about 400 Degree-Sign C.

Brudnyi, V. N., E-mail: brudnyi@mail.tsu.ru [Tomsk State University (Russian Federation); Verevkin, S. S. [Karpov Institute of Physical Chemistry (Russian Federation); Govorkov, A. V. [Joint Stock Company 'Federal State Research and Design Institute of Rare Metal Industry (Giredmet)' (Russian Federation); Ermakov, V. S.; Kolin, N. G.; Korulin, A. V. [Karpov Institute of Physical Chemistry (Russian Federation); Polyakov, A. Ya.; Smirnov, N. B. [Joint Stock Company 'Federal State Research and Design Institute of Rare Metal Industry (Giredmet)' (Russian Federation)

2012-04-15T23:59:59.000Z

369

Growth and photoluminescence of self-catalyzed GaP/GaNP core/shell nanowires on Si(111) by gas source molecular beam epitaxy  

Science Conference Proceedings (OSTI)

We report a study on self-catalyzed GaP/GaNP core/shell nanowires (NWs) grown on Si(111) by gas-source molecular beam epitaxy. Scanning electron microscopy images show that vertical and uniform GaP NWs and GaP/GaNP core/shell NWs are grown on Si(111). The density ranges from {approx}1 x 10{sup 7} to {approx}5 x 10{sup 8} cm{sup -2} across the substrate. Typical diameters are {approx}110 nm for GaP NWs and {approx}220 nm for GaP/GaNP NWs. Room temperature photoluminescence (PL) signal from the GaP/GaNP core/shell NWs confirms that N is incorporated in the shell and the average N content is {approx}0.9%. The PL low-energy tail is significantly reduced, compared to bulk GaNP.

Kuang, Y. J. [Department of Physics, University of California, San Diego, La Jolla, California 92093 (United States); Sukrittanon, S. [Graduate Program of Material Science and Engineering, University of California, San Diego, La Jolla, California 92093 (United States); Li, H. [Department of Electrical and Computer Engineering, University of California, San Diego, La Jolla, California 92093 (United States); Tu, C. W. [Graduate Program of Material Science and Engineering, University of California, San Diego, La Jolla, California 92093 (United States); Department of Electrical and Computer Engineering, University of California, San Diego, La Jolla, California 92093 (United States)

2012-01-30T23:59:59.000Z

370

2012 ALS User Meeting Awards  

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

ALS User Meeting Awards Print Recipients of the 2012 Users' Executive Committee awards and Student Poster Competition were announced Tuesday, October 9, at the ALS User Meeting....

371

2012 ALS User Meeting Awards  

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

Awards 2012 ALS User Meeting Awards Print Recipients of the 2012 Users' Executive Committee awards and Student Poster Competition were announced Tuesday, October 9, at the ALS User...

372

2012 ALS User Meeting Awards  

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

2 ALS User Meeting Awards Recipients of the 2012 Users' Executive Committee awards and Student Poster Competition were announced Tuesday, October 9, at the ALS User Meeting. David...

373

2012 ALS User Meeting Awards  

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

2012 ALS User Meeting Awards Print Recipients of the 2012 Users' Executive Committee awards and Student Poster Competition were announced Tuesday, October 9, at the ALS User...

374

A novel approach for the improvement of open circuit voltage and fill factor of InGaAsSb/GaSb thermophotovoltaic cells  

DOE Green Energy (OSTI)

Heterojunction n-Al{sub 0.25}Ga{sub 0.75}As{sub 0.02}Sb{sub 098}/p-In{sub 0.16}Ga{sub 0.84}As{sub 0.04}Sb{sub 0.96} thermophotovoltaic (TPV) cells were grown by molecular-beam epitaxy on n-GaSb-substrates. In the spectral range from 1 {micro}m to 2.1 {micro}m these cells, as well as homojunction n-p-In{sub 0.16}Ga{sub 0.84}As{sub 0.04}Sb{sub 0.96} cells, have demonstrated internal quantum efficiencies exceeding 80%, despite about a 200 meV barrier in the conduction band at the heterointerface. Estimation shows that the thermal emission of the electrons photogenerated in p-region over this barrier can provide high efficiency for hetero-cells if the electron recombination time in p-In{sub 0.16}Ga{sub 0.84}As{sub 0.04}Sb{sub 0.96}is longer than 10 ns. Keeping the same internal efficiency as homojunction cells, hetero-cells provide a unique opportunity to decrease the dark forward current and thereby increase open circuit voltage (V{sub {proportional_to}}) and fill factor at a given illumination level. It is shown that the decrease of the forward current in hetero-cells is due to the lower recombination rate in n-type wider-bandgap space-charge region and to the suppression of the hole component of the forward current. The improvement in V{sub {proportional_to}} reaches 100% at illumination level equivalent to 1 mA/cm{sup 2} and it decreases to 5% at the highest illumination levels (2--3 A/cm{sup 2}), where the electron current component dominates in both the homo- and heterojunction cells. Values of V{sub {proportional_to}} as high as 310 meV have been obtained for a hetero-cell at illumination levels of 3 A/cm{sup 2}. Under this condition, the expected fill factor value is about 72% for a hetero-cell with improved series resistance. The heterojunction concept provides excellent prospects for further reduction of the dark forward current in TPV cells.

Garbuzov, D.Z.; Martinelli, R.U.; Khalfin, V.; Lee, H.; Morris, N.A.; Taylor, G.C.; Connolly, J.C. [Sarnoff Corp., Princeton, NJ (United States); Charache, G.W.; DePoy, D.M. [Lockheed-Martin, Inc., Schenectady, NY (United States)

1997-10-01T23:59:59.000Z

375

Realization of low resistive p-ZnO thin film by Al-As codoping  

Science Conference Proceedings (OSTI)

Al-As codoping into ZnO has been proposed to realize low resistive and stable p-ZnO thin film by RF magnetron sputtering. Al-As codoping has been achieved by As back diffusion from GaAs substrate and sputtering Al doped ZnO target. Hall measurements showed that the hole concentration increases with the increase of Al concentration from 10{sup 15} to 10{sup 20} cm{sup -3}. Among the grown films, 1 at% Al doped ZnO: As showed low resistivity (3.5x10{sup -2}{Omega}cm) with high hole concentration. X-ray diffraction shows that all the films are crystallized in wurtzite structure with (002) preferential orientation. The diffusion of As atoms from the substrate and the presence of dopants in the film have been confirmed by Rutherford ford back scattering and energy dispersive spectroscopy analysis, respectively.

Balakrishnan, L.; Gowrishankar, S.; Gopalakrishnan, N. [Thin Film Laboratory, Department of Physics, National Institute of Technology, Tiruchirappalli 620015 (India)

2012-06-05T23:59:59.000Z

376

Growth orientation dependent photoluminescence of GaAsN alloys  

SciTech Connect

We report photoluminescence (PL) studies of both as-grown and electron-irradiated GaAsN epilayers on (311)A/B and (100) GaAs substrates. A long room-temperature (RT) PL lifetime, as well as an enhanced N incorporation, is observed in (311)B GaAsN epilayers as compared with (311)A and (100) samples. There is no direct correlation between the RT PL lifetime and the emission intensity from Ga vacancy complex detected at low temperature. The lifetime damage coefficient is relatively low for (311)B GaAsN. The irradiation-induced nonradiative recombination defects are suggested to be N- and/or As-related according to a geometrical analysis based on the tetrahedral coordination of GaAsN crystal.

Han, Xiuxun; Tanaka, Tomohiro; Kojima, Nobuaki; Ohshita, Yoshio; Yamaguchi, Masafumi [Toyota Technological Institute, 2-12-1 Hisakata, Tempaku, Nagoya 468-8511 (Japan); Sato, Shinichiro [Japan Atomic Energy Agency, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan)

2012-01-16T23:59:59.000Z

377

Effect of Temperature on GaGdO/GaN Metal Oxide Semiconductor Field Effect Transistors  

SciTech Connect

GaGdO was deposited on GaN for use as a gate dielectric in order to fabricate a depletion metal oxide semiconductor field effect transistor (MOSFET). This is the fmt demonstration of such a device in the III-Nitride system. Analysis of the effect of temperature on the device shows that gate leakage is significantly reduced at elevated temperature relative to a conventional metal semiconductor field effeet transistor (MESFET) fabricated on the same GaN layer. MOSFET device operation in fact improved upon heating to 400 C. Modeling of the effeet of temperature on contact resistance suggests that the improvement is due to a reduction in the parasitic resistances present in the device.

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

1998-10-14T23:59:59.000Z

378

A InGaN/GaN quantum dot green ({lambda}=524 nm) laser  

SciTech Connect

The characteristics of self-organized InGaN/GaN quantum dot lasers are reported. The laser heterostructures were grown on c-plane GaN substrates by plasma-assisted molecular beam epitaxy and the laser facets were formed by focused ion beam etching with gallium. Emission above threshold is characterized by a peak at 524 nm (green) and linewidth of 0.7 nm. The lowest measured threshold current density is 1.2 kA/cm{sup 2} at 278 K. The slope and wall plug efficiencies are 0.74 W/A and {approx}1.1%, respectively, at 1.3 kA/cm{sup 2}. The value of T{sub 0}=233 K in the temperature range of 260-300 K.

Zhang Meng; Banerjee, Animesh; Lee, Chi-Sen; Hinckley, John M.; Bhattacharya, Pallab [Department of Electrical Engineering and Computer Science, Center for Nanoscale Photonics and Spintronics, University of Michigan, Ann Arbor, Michigan 48109-2122 (United States)

2011-05-30T23:59:59.000Z

379

GaInSb and GaInAsSb thermophotovoltaic device fabrication and characterization  

DOE Green Energy (OSTI)

Thermophotovoltaic (TPV) devices have been fabricated using epitaxial ternary and quaternary layers grown on GaSb substrates. The GaInSb layers were grown by organometallic vapor phase epitaxy (OMVPE) and the InGaAsSb lattice-matched layers were grown by liquid phase epitaxy (LPE). Device fabrication steps include unannealed p-type ohmic contacts, annealed Sn/Au n-type ohmic contacts, and a thick Ag top-surface contact using a lift-off process. Devices are characterized primarily by dark I-V, photo I-V, and quantum efficiency measurements, which are correlated to microscopic and macroscopic material properties. Particular emphasis has been on material enhancements to increase quantum efficiency and decrease dark saturation current density. TPV device performance is presently limited by the base diffusion length, typically 1 to 2 microns.

Hitchcock, C.; Gutmann, R.; Borrego, J.; Ehsani, H.; Bhat, I. [Rensselaer Polytechnic Inst., Troy, NY (United States); Freeman, M.; Charache, G. [Lockheed Martin, Inc., Schenectady, NY (United States)

1997-05-01T23:59:59.000Z

380

Transport properties of InGaAs/GaAs Heterostructures with {delta}-doped quantum wells  

Science Conference Proceedings (OSTI)

The lateral transport of electrons in single- and double-well pseudomorphic GaAs/n-InGaAs/GaAs heterostructures with quantum wells 50-100 meV deep and impurity {delta}-layers in the wells, with concentrations in the range 10{sup 11} electron mobility with an increase in the impurity concentration. The results obtained indicate that the impurity-band electron states play an important role in the conductivity of these structures. Involvement of the impurity band also allows to explain adequately the characteristics of the conductivity of double-well structures; in contrast to single-well structures, band bending caused by asymmetric doping is of great importance. The numerical calculations of conductivity within the model under consideration confirm these suggestions.

Baidus, N. V. [Nizhni Novgorod State University, Physical-Technical Research Institute (Russian Federation); Vainberg, V. V. [National Academy of Sciences of Ukraine, Institute of Physics (Ukraine); Zvonkov, B. N. [Nizhni Novgorod State University, Physical-Technical Research Institute (Russian Federation); Pylypchuk, A. S., E-mail: pylypchuk@iop.kiev.ua; Poroshin, V. N.; Sarbey, O. G. [National Academy of Sciences of Ukraine, Institute of Physics (Ukraine)

2012-05-15T23:59:59.000Z

Note: This page contains sample records for the topic "tn al ga" 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

I I I I OA RIDGE I TIO AL  

Office of Legacy Management (LM)

I I I OA RIDGE I TIO AL aORATOR I I IWARTIN IWARIETTA I I I I I I I I I I I ANAGfD BY ARTIN ARIEllA ENERGY SYSTE S, I C. FOR THE UNITED STATES I OEPARTME T OF E ERGY 9007 ORNlJRASA-93/2 Results of the Radiological Survey at the Fonner Associate Aircraft Tool and Manufacturing Company Site, Fairfield, Ohio (FOHOOl) M. E. Murray R. F. Carrier R. A. Mathis I I I I I Thl8 report has been reproduced d'rectly from the best available copy. I Av labIe to DOE and DOE contractors from the Office of Scientific end Techni- cal Information, P.O. Box 62. Oak Ridge, TN 37831: prices available from (615) 576-8401, FTS 626-8401. Available to the public from the National Technical Intonnatioo Service, U.S. Department of Commerce, 5285 Port Royal Rd., Springfield, VA 22161. I I This report was prepared as an account of work sponsored by an agency of

382

II4, Compositionally-Graded Layers Composed of Tandem InGaAs ...  

Science Conference Proceedings (OSTI)

The specification of the 6° miscut is important because it provides step ..... of Metamorphic InGaP on GaAs and GaP for Wide-Bandgap Photovoltaic Junctions.

383

(AlIn)GaN Multi Quantum Wells for Blue Lasers by ...  

Science Conference Proceedings (OSTI)

... 13th International Conference on Defects--Recognition, Imaging and Physics in ... Capacitance Spectroscopy of Deep States in Quantum Dot Heterostructures.

384

B4, Admittance Spectroscopy of GaSb(100) and ALD / PEALD Al 2 O ...  

Science Conference Proceedings (OSTI)

PEALD was employed to reduce the thermal budget of dielectric deposition, ..... Bands and Hopping-Induced Mixed Valence for Ti and Sc in GdSc1-x TixO3 for x  ...

385

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 ...

386

Highly Polarized Green Light Emitting Diode in m-Axis GaInN/GaN Shi You, Theeradetch Detchprohm, Mingwei Zhu  

E-Print Network (OSTI)

Highly Polarized Green Light Emitting Diode in m-Axis GaInN/GaN Shi You, Theeradetch Detchprohm in nonpolar light-emitting diodes (LEDs) covering the blue to green spectral range. In photo- luminescence, m's overall power efficiency. Linearly polarized light can be efficiently generated in GaInN/GaN-based light-emitting

Wetzel, Christian M.

387

Atomistic Modeling of Thermodynamic Properties of Pu-Ga Alloys ...  

Science Conference Proceedings (OSTI)

Atomistic Modeling of Thermodynamic Properties of Pu-Ga Alloys Based on the ... Resources for the Selection and Use of Interatomic Potentials in Atomistic ...

388

GA Hot Cell D&D Closeout Report  

Office of Legacy Management (LM)

contractors supported the dismantlement including asbestos removal and concrete cutting, electrical, and HVAC. Project support functions were provided by GA organizations...

389

Light emission from InGaAs:Bi/GaAs quantum wells at 1.3 {mu}m  

Science Conference Proceedings (OSTI)

Highly strained InGaAs:Bi quantum wells (QWs) were grown on (001)-oriented GaAs substrates by molecular beam epitaxy (MBE). Photoluminescence (PL) reveals strong improvements in the optical properties evidenced by 10 times enhancement in PL intensity and extended emission wavelength up to 1.29 {mu}m when Bi is introduced to InGaAs/GaAs QWs. The improved optical quality results from the Bi surfactant effect as well as the Bi incorporation. Post growth thermal annealing shows that Bi atoms in InGaAs/GaAs QWs do not show good thermal stability at 650 Degree-Sign C and tend to diffuse out of the QWs resulting in large wavelength blue-shifts.

Ye Hong; Song Yuxin; Wang Shumin [Department of Microtechnology and Nanoscience, Chalmers University of Technology, Gothenburg SE-41296 (Sweden); Gu Yi [Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China)

2012-12-15T23:59:59.000Z

390

Impact of the Ga/In ratio on the N incorporation into (In,Ga)(As,N) quantum dots  

Science Conference Proceedings (OSTI)

In this work, we demonstrate the dependence of the nitrogen incorporation on the Ga/In content into (In,Ga)(As,N) quantum dots (QDs) grown on GaAs (100) by radio-frequency plasma assisted molecular beam epitaxy (MBE). Morphological analysis by atomic force microscopy and cross-sectional transmission electron microscopy, together with an estimation of the transition thickness, monitored in situ during the growth, predict a maximum in the N incorporation for 30% Ga content. This result is confirmed by photoluminescence measurements of the as-grown and post-growth annealed samples. We attribute this behavior to a trade off between two mechanisms depending on the Ga/In content: one related to the stability of the Ga-N bond, and the other related to the surface strain and/or In segregation.

Gargallo-Caballero, R.; Guzman, A.; Ulloa, J. M.; Hierro, A. [Instituto de Sistemas Optoelectronicos y Microtecnologia (ISOM)-Departamento de Ingenieria Electronica, ETSI Telecomunicacion, Universidad Politecnica de Madrid, Ciudad Universitaria s/n, 28040 Madrid (Spain); Hopkinson, M. [Department of Electronic and Electrical Engineering, University of Sheffield, Sheffield S1 3JD (United Kingdom); Luna, E.; Trampert, A. [Paul Drude Institut fuer Festkoerperelektronik, Hausvogteiplatz 5-7, 10117 Berlin (Germany)

2012-04-15T23:59:59.000Z

391

Bulk growth of GaSb and Ga{sub 1{minus}x}In{sub x}Sb  

DOE Green Energy (OSTI)

GaSb and InGaSb have been demonstrated to be suitable choices for high efficiency thermophotovoltaic (TPV) cells. Synthesis and growth of bulk GaSb single crystals and GaInSb polycrystals have been carried out by the vertical Bridgman technique, with a baffle immersed in the melt and by complete encapsulation of the melt by low melting temperature alkali halides or oxides. The critical roles of the baffle and the encapsulation are discussed. Efforts in obtaining device grade GaSb with superior structural and electrical properties and compositionally homogeneous GaInSb are described, emphasizing the key steps in the growth cycle developed to obtain good crystalline quality.

Dutta, P.S.; Ostrogorsky, A.G.; Gutmann, R.J.

1997-05-01T23:59:59.000Z

392

Effect of gas feeding methods on optical properties of GaN grown by rapid thermal chemical vapor deposition reactor  

Science Conference Proceedings (OSTI)

Keywords: Ga vacancies, GaN growth, gas feeding method, optical property, rapid thermal chemical vapor deposition (RTCVD), yellow luminescence

Sun Jung Kim; Young Hun Seo; Kee Suk Nahm; Yun Bong Hahn; Hyun Wook Shim; Eun-Kyung Suh; Kee Young Lim; Hyung Jae Lee

1999-08-01T23:59:59.000Z

393

ALS Beamlines Directory  

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

Beamlines Directory Print Beamlines Directory Print Beamlines, Parameters, Contact Information, and Schedules Download a high-resolution version of the ALS Beamclock. See Beamclock to view the ALS energy-related beamlines beamclock. Beamline Parameters Beamline and endstation technical information is available through the links below. Unless otherwise noted, all beamlines are currently operational. Individual beamline schedules are posted when available. Please contact the responsible beamline scientist for additional schedule information. When calling from off-site, all beamline (BL) phone numbers that begin with a "2" are preceded by 495- (i.e., 495-2014); all others are preceded by 486-. Beamline Number Source Technique/ Group Name Energy Range Beamline Contact Schedule/BL Phone

394

ALS User Meeting Archives  

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

User Meeting Archives Print User Meeting Archives Print Past User Meeting Agendas, Workshops, and Awards Year Agenda Workshops David A. Shirley (Science) Klaus Halbach (Instrumentation) Tim Renner (Service) 2012 2012 User Meeting Agenda 2012 User Meeting Workshops 2012 ALS User Meeting Awards Carl Percival, Dudley Shallcross, Craig Taatjes and David Osborn (Sandia), for making the first direct measurements of the reactions of Criegee intermediates, and showing that their impact on tropospheric chemistry and climate may be substantially greater than previously assumed. 2012 ALS User Meeting Awards Jeff Dickert and Simon Morton of Berkeley Lab's Physical Biosciences Division for the invention and implementation of the Compact Variable Collimator (CVC), which has led to a dramatic increase in productivity of protein crystallography.

395

ALS Beamlines Directory  

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

Beamlines Directory Print Beamlines Directory Print Beamlines, Parameters, Contact Information, and Schedules Download a high-resolution version of the ALS Beamclock. See Beamclock to view the ALS energy-related beamlines beamclock. Beamline Parameters Beamline and endstation technical information is available through the links below. Unless otherwise noted, all beamlines are currently operational. Individual beamline schedules are posted when available. Please contact the responsible beamline scientist for additional schedule information. When calling from off-site, all beamline (BL) phone numbers that begin with a "2" are preceded by 495- (i.e., 495-2014); all others are preceded by 486-. Beamline Number Source Technique/ Group Name Energy Range Beamline Contact Schedule/BL Phone

396

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

Science Conference Proceedings (OSTI)

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

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

2012-09-06T23:59:59.000Z

397

Functional Imprinting Structures on GaN-Based Light-Emitting ...  

Science Conference Proceedings (OSTI)

Keywords: GaN, light-emitting diode (LED), imprinting technology, far-field pattern modulation, light extraction. 1. Introduction. GaN-based light-emitting diodes ...

398

Bonding and gap states at GaAs-oxide interfaces  

Science Conference Proceedings (OSTI)

The nature of bonding and possible causes of Fermi level pinning at high mobility-high dielectric constant oxide GaAs:HfO"2 interfaces are discussed. It is argued that these are atoms with defective bonding, rather than states due to the bulk semiconductor ... Keywords: GaAs, bonding, interface

John Robertson; Liang Lin

2011-04-01T23:59:59.000Z

399

Multiconfiguration Dirac-Fock calculations on multi-valence-electron systems: Benchmarks on Ga-like ions  

Science Conference Proceedings (OSTI)

High-accuracy calculations of term energies and wavelengths of resonance lines in Ga-like ions have been performed as benchmarks in the request for accurate treatments of relativity, electron correction, and QED effects in multi-valence-electron systems. The calculated energy levels are in excellent agreement with the experimental results and the experimentally compiled energy values of the National Institute for Standards and Technology wherever available. The calculated values including core-valence correction are found to be in good agreement with other theoretical and experimental values for low- to medium-Z ions. On the basis of our calculations, some theoretical wavelengths for Ga-like Rb vii to Mo xii are also given. For higher-Z ions, computed wavelengths are compared well with the experimental results [E. Traebert, J. Clementson, P. Beiersdorfer, J. A. Santana, and Y. Ishikawa, Phys. Rev. A 82, 062519 (2010), I. N Draganicet al., J. Phys. B 44, 025001 (2011)].

Hu Feng [Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang, 621900 Sichuan (China); Institute of Atomic and Molecular Physics, Sichuan University, Chengdu, 610065 Sichuan (China); Yang Jiamin; Wang Chuanke; Jing Longfei; Chen Shubo [Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang, 621900 Sichuan (China); Jiang Gang; Liu Hao; Hao Lianghuan [Institute of Atomic and Molecular Physics, Sichuan University, Chengdu, 610065 Sichuan (China)

2011-10-15T23:59:59.000Z

400

Elastic properties of Pu metal and Pu-Ga alloys  

Science Conference Proceedings (OSTI)

We present elastic properties, theoretical and experimental, of Pu metal and Pu-Ga ({delta}) alloys together with ab initio equilibrium equation-of-state for these systems. For the theoretical treatment we employ density-functional theory in conjunction with spin-orbit coupling and orbital polarization for the metal and coherent-potential approximation for the alloys. Pu and Pu-Ga alloys are also investigated experimentally using resonant ultrasound spectroscopy. We show that orbital correlations become more important proceeding from {alpha} {yields} {beta} {yields} {gamma} plutonium, thus suggesting increasing f-electron correlation (localization). For the {delta}-Pu-Ga alloys we find a softening with larger Ga content, i.e., atomic volume, bulk modulus, and elastic constants, suggest a weakened chemical bonding with addition of Ga. Our measurements confirm qualitatively the theory but uncertainties remain when comparing the model with experiments.

Soderlind, P; Landa, A; Klepeis, J E; Suzuki, Y; Migliori, A

2010-01-05T23:59:59.000Z

Note: This page contains sample records for the topic "tn al ga" 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

2012 ALS User Meeting Awards  

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

2 ALS User Meeting Awards 2012 ALS User Meeting Awards Print Wednesday, 10 October 2012 15:30 Recipients of the 2012 Users' Executive Committee awards and Student Poster...

402

Near ultraviolet emission from nonpolar cubic AlxGa1-xN/GaN quantum wells  

E-Print Network (OSTI)

Near ultraviolet emission from nonpolar cubic AlxGa1-xN/GaN quantum wells J. Schörmann,a S and multiple quantum wells. The well widths ranged from 2.5 to 7.5 nm. Samples were grown by rf-plasma assisted wells clear reflection high energy electron diffraction oscillations were observed indicating a two

As, Donat Josef

403

Development of high power green light emitting diode dies in piezoelectric GaInN/GaN  

E-Print Network (OSTI)

Development of high power green light emitting diode dies in piezoelectric GaInN/GaN Christian in green light emitting diodes is one of the big challenges towards all-solid- state lighting. The prime,3], and commercialization [4,5] of high brightness light emitting diodes LEDs has led to a 1.82 Billion-$/year world market

Detchprohm, Theeradetch

404

Wavelength-resolved low-frequency noise of GaInN/GaN green light emitting diodes  

E-Print Network (OSTI)

Wavelength-resolved low-frequency noise of GaInN/GaN green light emitting diodes S. L. Rumyantseva well light emitting diodes. The light intensity noise was measured as a function of wavelength within the light emitting diode spectral emission line. The spectral noise density is found to increase

Wetzel, Christian M.

405

Lasing characteristics of GaSb/GaAs self-assembled quantum dots embedded in an InGaAs quantum well  

E-Print Network (OSTI)

be applicable to light sources in fiber-optic communication systems.13 However, there have been no reports intriguing optoelectronic device possibilities on GaAs substrates including lasers, detectors, or solar cells

Jalali. Bahram

406

Structural and optical studies of nitrogen incorporation into GaSb-based GaInSb quantum wells  

Science Conference Proceedings (OSTI)

We investigate the incorporation of nitrogen into (Ga,In)Sb grown on GaSb and report room temperature photoluminescence from GaInSb(N) quantum wells. X-ray diffraction and channeling nuclear reaction analysis, together with Rutherford backscattering, were employed to identify the optimal molecular beam epitaxial growth conditions that minimized the incorporation of non-substitutional nitrogen into GaNSb. Consistent with this hypothesis, GaInSb(N) quantum wells grown under the conditions that minimized non-substitutional nitrogen exhibited room temperature photoluminescence, indicative of significantly improved radiative efficiency. Further development of this material system could enable type-I laser diodes emitting throughout the (3-5 {mu}m) wavelength range.

Nair, Hari P.; Crook, Adam M.; Bank, Seth R. [Microelectronics Research Center, Electrical and Computer Engineering, University of Texas at Austin, 10100 Burnet Rd, Austin, Texas 78712 (United States); Yu, Kin M. [Electronic Materials Program, Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

2012-01-09T23:59:59.000Z

407

GaSb/GaAs quantum dot formation and demolition studied with cross-sectional scanning tunneling microscopy  

Science Conference Proceedings (OSTI)

We present a cross-sectional scanning tunneling microscopy study of GaSb/GaAs quantum dots grown by molecular beam epitaxy. Various nanostructures are observed as a function of the growth parameters. During growth, relaxation of the high local strain fields of the nanostructures plays an important role in their formation. Pyramidal dots with a high Sb content are often accompanied by threading dislocations above them. GaSb ring formation is favored by the use of a thin GaAs first cap layer and a high growth temperature of the second cap layer. At these capping conditions, strain-driven Sb diffusion combined with As/Sb exchange and Sb segregation remove the center of a nanostructure, creating a ring. Clusters of GaSb without a well defined morphology also appear regularly, often with a highly inhomogeneous structure which is sometimes divided up in fragments.

Smakman, E. P.; Garleff, J. K.; Rambabu, P.; Koenraad, P. M. [Department of Applied Physics, Eindhoven University of Technology, Eindhoven 5612 AZ (Netherlands); Young, R. J.; Hayne, M. [Department of Physics, Lancaster University, Lancaster LA1 4YB (United Kingdom)

2012-04-02T23:59:59.000Z

408

U.S. Energy Information Administration | Annual Energy Outlook...  

Gasoline and Diesel Fuel Update (EIA)

Annual Energy Outlook 2012 Regional maps Figure F6. Coal supply regions WA ID OR CA NV UT TX OK AR MO LA MS AL GA FL TN SC NC KY VA WV WY CO SD ND MI MN WI IL IN OH MD PA NJ DE CT...

409

C:\\ANNUAL\\VENTCHAP.V8\\NGA.VP  

Gasoline and Diesel Fuel Update (EIA)

4 NJ WY AK AL CA AR CO CT DE FL GA HI ID KS IL IN IA IA KY LA ME MI MA MD MN MS MT MO NE ND OH NV NM NY NH NC OK OR PA RI SC SD TN TX UT VT WA WV WI AZ VA DC 0.00-1.99 2.00-2.99...

410

Microsoft Word - NGAMaster_State_TablesNov12.doc  

Gasoline and Diesel Fuel Update (EIA)

WI NE IA KS MO TX IL IN OH MI OK AR TN WV VA KY MD PA WI NY VT NH MA CT ME RI NJ DC NC SC GA AL MS LA FL HI AK DE 0 2 4 6 8 10 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998...

411

C:\\ANNUAL\\VENTCHAP.V8\\NewNGA02.vp  

Gasoline and Diesel Fuel Update (EIA)

NE IA KS MO TX IL IN OH MI OK AR TN W VA KY MD PA WI NY VT NH MA CT ME RI NJ DE DC NC SC GA AL MS LA FL HI AK 15. Marketed Production of Natural Gas in the United States, 2001...

412

C:\\ANNUAL\\VENTCHAP.V8\\NGAla1109.vp  

Gasoline and Diesel Fuel Update (EIA)

0 NJ WY AK AL CA AR CO CT DE FL GA HI ID KS IL IN IA IA KY LA ME MI MA MD MN MS MT MO NE ND OH NV NM NY NH NC OK OR PA RI SC SD TN TX UT VT WA WV WI AZ VA DC Sources: Energy...

413

NGA98fin5.vp  

Annual Energy Outlook 2012 (EIA)

NJ WY AK AL CA AR CO CT DE FL GA HI ID KS IL IN IA IA KY LA ME MI MA MD MN MS MT MO NE ND OH NV NM NY NH NC OK OR PA RI SC SD TN TX UT VT WA WV WI AZ VA DC 0.00-1.99 2.00-2.99...

414

U.S. Energy Information Administration | Annual Energy Outlook...  

Annual Energy Outlook 2012 (EIA)

3 Regional maps Figure F6. Coal supply regions WA ID OR CA NV UT TX OK AR MO LA MS AL GA FL TN SC NC KY VA WV WY CO SD ND MI MN WI IL IN OH MD PA NJ DE CT MA NH VT NY ME RI MT NE...

415

U.S. Energy Information Administration | Annual Energy Outlook...  

Gasoline and Diesel Fuel Update (EIA)

1 Regional maps Figure F4. Oil and gas supply model regions Figure F4. Oil and Gas Supply Model Regions Atlantic WA MT WY ID NV UT CO AZ NM TX OK IA KS MO IL IN KY TN MS AL FL GA...

416

Gas Prices  

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

Prices Gasoline Prices for U.S. Cities Click on the map to view gas prices for cities in your state. AK VT ME NH NH MA MA RI CT CT DC NJ DE DE NY WV VA NC SC FL GA AL MS TN KY IN...

417

Effect of Sb on the Properties of GaInP Top Cells (Presentation)  

DOE Green Energy (OSTI)

The summary of this report is that: (1) Sb can be used to increase V{sub oc} of a GaInP top cell; (2) the photovoltaic quality of GaInP is relatively unaffected by the presence of Sb; and (3) Sb-doped GaInP/GaAs tandem cells show promise for achieving efficiencies over 32%.

Olson, J. M.; McMahon, W. E.; Kurtz, S.

2006-05-01T23:59:59.000Z

418

Negative ion photodetachment spectroscopy of the Al3O2 , Al3O3 , Al4Ox , Al5Ox (x = 35), Al6O5 , and Al7O5 clusters  

E-Print Network (OSTI)

Negative ion photodetachment spectroscopy of the Al3O2 , Al3O3 , Al4Ox , Al5Ox (x = 3­5), Al6O5 , and Al7O5 clusters Giovanni Meloni, Michael J. Ferguson and Daniel M. Neumark Department of Chemistry as an Advance Article on the web 9th September 2003 The Al3O2 , Al3O3 , Al4Ox , Al5Ox (x ¼ 3­5), Al6O5 , and Al7

Neumark, Daniel M.

419

2013 ALS User Meeting Highlights  

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

2013 ALS User Meeting Highlights 2013 ALS User Meeting Highlights 2013 ALS User Meeting Highlights Print This year's ALS User Meeting launched with a welcome from Users' Executive Committee Chair Corie Ralston and LBNL Director Paul Alivisatos. ALS Director Roger Falcone followed with a "state of the ALS" presentation that began with a reminder of the ALS mission, which he noted remains true even in the midst of a government shutdown: "Supporting users in doing outstanding science in a safe environment." Falcone gave the 414 meeting attendees an update on the ALS beamlines, which included good news about increased user numbers thanks to the new RAPIDD access system, enhanced robotics, and remote capabilities. Falcone reflected that ALS metrics continue to represent our highly productive users-the number of journal articles and papers per user that come from ALS research have continued to grow in the past year. Looking forward, Falcone touched on how a proposed ALS upgrade to a diffraction-limited light source would increase scientific capabilities.

420

2013 ALS User Meeting Highlights  

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

2013 ALS User Meeting Highlights 2013 ALS User Meeting Highlights 2013 ALS User Meeting Highlights Print Thursday, 24 October 2013 09:06 This year's ALS User Meeting launched with a welcome from Users' Executive Committee Chair Corie Ralston and LBNL Director Paul Alivisatos. ALS Director Roger Falcone followed with a "state of the ALS" presentation that began with a reminder of the ALS mission, which he noted remains true even in the midst of a government shutdown: "Supporting users in doing outstanding science in a safe environment." Falcone gave the 414 meeting attendees an update on the ALS beamlines, which included good news about increased user numbers thanks to the new RAPIDD access system, enhanced robotics, and remote capabilities. Falcone reflected that ALS metrics continue to represent our highly productive users-the number of journal articles and papers per user that come from ALS research have continued to grow in the past year. Looking forward, Falcone touched on how a proposed ALS upgrade to a diffraction-limited light source would increase scientific capabilities.

Note: This page contains sample records for the topic "tn al ga" 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

Atomic hydrogen cleaning of polarized GaAs photocathodes  

DOE Green Energy (OSTI)

Atomic hydrogen cleaning followed by heat cleaning at 450 C was used to prepare negative-electron-affinity GaAs photocathodes. When hydrogen ions were eliminated, quantum efficiencies of 15% were obtained for bulk GaAs cathodes, higher than the results obtained using conventional 600 C heat cleaning. The low-temperature cleaning technique was successfully applied to thin, strained GaAs cathodes used for producing highly polarized electrons. No depolarization was observed even when the optimum cleaning time of about 30 seconds was extended by a factor of 100.

Maruyama, Takashi

2003-04-03T23:59:59.000Z

422

ENVIRONMENT AL REVI  

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

ENVIRONMENT ENVIRONMENT AL REVI EW for CATEG ORI CAL EXCLUS ION DETE RMINATION Rocky Mo unta in Region, Weste rn A rea Power Administra tion Stru cture Replace ment Fla min g Go rge-Vern a l No.3 138-kV tra nsmiss ion lin e (Struct ure No. 25/6) Spr ing 201 2 A. Ilricf J)cscription of Proposal: Western Area Power Adm inistration (Western) proposes to replace Structure No. 25/6 on the Flaming Gorge-Vernal No.3 138-kV transmission line. The structure is located on Bureau of Land Management lands in Uintah County. Utah (Township 3S, Range 22E, Section 7; Donkey Flat 7.5' USGS quadrangle). Work consists of removal and in-kind replacement of the wood H-frame structure and anchors utilizing rubber tired vehicles. crane, bucket truck, pole trucks/trailers, auger rig. and pick-up trucks. All work will be conducted on Western's existing

423

Outdoor Testing of GaInP2/GaAs Tandem Cells with Top Cell Thickness Varied  

DOE Green Energy (OSTI)

In this study, we measure the performance of GaInP2/GaAs tandem cells under direct beam sunlight outdoors in order to quantify their sensitivity to both spectral variation and GaInP2 top-cell thickness. A set of cells with five different top-cell thicknesses was mounted on a two-axis tracker with the incident sunlight collimated to exclude all except the direct beam. Current-voltage (I-V) curves were taken throughout the course of several days, along with measurements of the direct solar spectrum. Our two major conclusions are: (1) GaInP2/GaAs tandem cells designed for either the ASTM G-173 direct (G-173D) spectrum or the "air mass 1.5 global" (AM1.5G) spectrum perform the best, and (2) cells can be characterized indoors and modeled using outdoor spectra with the same result. These results are equally valid for GaInP2/GaAs/Ge triple-junction cells.

McMahon, W. E.; Emergy, K. E.; Friedman, D. J.; Ottoson, L.; Young, M. S.; Ward, J. S.; Kramer, C. M.; Duda, A.; Kurtz, S.

2005-08-01T23:59:59.000Z

424

On-Sun Comparison of GaInP2/GaAs Tandem Cells with Top Cell Thickness Varied  

DOE Green Energy (OSTI)

This study compares the on-sun performance of a set of GaInP2/GaAs tandem cells with different GaInP2 top-cell thicknesses. Because high-efficiency III-V cells are best suited to concentrating photovoltaic (CPV) applications, the cells were mounted on a two-axis tracker with the incident sunlight collimated to exclude all except the direct beam. Current-voltage (I-V) curves were taken throughout the course of several days, along with measurements of the direct solar spectrum. Our two major conclusions are: (1) GaInP2/GaAs tandem cells designed for an ''air mass 1.5 global'' (AM 1.5G) or a ''low aerosol optical depth'' (Low AOD) spectrum perform the best, and (2) cells can be characterized indoors and modeled using outdoor spectra to predict the correct result. These results are equally valid for GaInP2/GaAs/Ge triple-junction cells.

McMahon, W. E.; Emery, K. E.; Friedman, D. J.; Ottoson, L.; Young, M. S.; Ward, J. S.; Kramer, C. M.; Duda, A.; Kurtz, S.

2005-02-01T23:59:59.000Z

425

Promising Magnesium Battery Research at ALS  

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

AdvancedLightSource Home Science Highlights Industry @ ALS Promising Magnesium Battery Research at ALS Promising Magnesium Battery Research at ALS Print Wednesday, 23...

426

Das Leben als Krankheit: Kafkas Ein Landarzt  

E-Print Network (OSTI)

Das Leben als Krankheit. Franz Kafkas Ein Landarzt Muhammedsei. Die menschliche Existenz als eine unheilbare Krankheit:Vorstellung vom Menschen als Be- herrscher seines Lebens.

Al-Azzawi, Muhammed

2011-01-01T23:59:59.000Z

427

Joint SSRTNet/ALS-MES Workshop report  

E-Print Network (OSTI)

conclusion of his SRRTNet/ALS-MES Workshop presentation inJoint SSRTNet/ALS-MES Workshop This joint workshop broughtthe Advanced Light Source (ALS) Users’ Association Annual

Shuh, David; Van Hove, Michel

2001-01-01T23:59:59.000Z

428

ALS Beamline Design Requirements - Revision 1  

E-Print Network (OSTI)

materials are not allowed in the ALS experiment area withoutlocations provided by the ALS. c. Cleaning proceduresa successful walkthrough, the ALS Director or designee gives

Heimann, Phil

2010-01-01T23:59:59.000Z

429

2012 ALS User Meeting Highlights  

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

and notable science highlights, which communicated ALS advances in structural biology, battery research, and fundamental science. Falcone acknowledged the work of Simon Morton and...

430

ALS Scientific Advisory Committee Charter  

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

This document was revised and approved December 18, 2008. I. FUNCTION AND REPORTING The ALS Scientific Advisory Committee (SAC) is advisory to the Berkeley Lab Director through...

431

FUPWG Meeting Agenda - Atlanta, GA | Department of Energy  

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

Atlanta, GA Atlanta, GA FUPWG Meeting Agenda - Atlanta, GA October 7, 2013 - 3:16pm Addthis Energy on My Mind / FUPWG / Atlanta, GA / May 3-4, 2006 Hosted by: AGL Resources Logo May 3-4, 2006 Hosted by AGL Resources Atlanta, Georgia Tuesday, May 2, 2006 5:00 - 6:30 Steering Committee meeting in the Danube Tigris Room 6:30 until... Networking dinner at the Marriott Wednesday, May 3, 2006 7:45 am Registration/Continental Breakfast 8:30 - 8:45 Welcome from Suzanne Sitherwood, SVP, Southern Operations, President, Atlanta Gas Light, Chattanooga Gas & Florida City Gas 8:45 - 9:00 FEMP Southeast Regional Office Welcome Traci Leath, FEMP 9:00 - 9:45 Washington Update David McAndrew, FEMP 9:45 - 10:15 Break - Networking 10:15 - 11:20 Navy Technical Program Update Paul Kistler, U.S. Navy

432

Elba Island, GA Liquefied Natural Gas Imports from Qatar (Million...  

U.S. Energy Information Administration (EIA) Indexed Site

Liquefied Natural Gas Imports from Qatar (Million Cubic Feet) Elba Island, GA Liquefied Natural Gas Imports from Qatar (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep...

433

Lattice vibrations of pure and doped GaSe  

Science Conference Proceedings (OSTI)

The Bridgman method is used to grow especially undoped and doped single crystals of GaSe. Composition and impurity content of the grown crystals were determined using X-ray fluorescence (XRF) method. X-ray diffraction, Raman scattering, photoluminescence (PL), and IR transmission measurements were performed at room temperature. The long wavelength lattice vibrations of four modifications of GaSe were described in the framework of modified one-layer linear-chain model which also takes into consideration the interaction of the selenium (Se) atom with the second nearest neighbor gallium (Ga) atom in the same layer. The existence of an eight-layer modification of GaSe is suggested and the vibrational frequencies of this modification are explained in the framework of a lattice dynamical model considered in the present work. Frequencies and the type of vibrations (gap, local, or resonance) for the impurity atoms were calculated and compared with the experimental results.

Allakhverdiev, K. [Materials Institute, Marmara Research Center, TUBITAK, Gebze/Kocaeli 41470 (Turkey) and Institute of Physics, Azerbaijan National Academy of Sciences, Baku AZ1143 (Azerbaijan)]. E-mail: kerim.allahverdi@mam.gov.tr; Baykara, T. [Materials Institute, Marmara Research Center, TUBITAK, Gebze/Kocaeli 41470 (Turkey); Ellialtioglu, S. [Department of Physics, Middle East Technical University, Ankara 06531 (Turkey); Hashimzade, F. [Institute of Physics, Azerbaijan National Academy of Sciences, Baku AZ1143 (Azerbaijan); Huseinova, D. [Institute of Physics, Azerbaijan National Academy of Sciences, Baku AZ1143 (Azerbaijan); Kawamura, K. [Institute of Materials Science, University of Tsukuba 305-8573 (Japan); Kaya, A.A. [Materials Institute, Marmara Research Center, TUBITAK, Gebze/Kocaeli 41470 (Turkey); Kulibekov, A.M. [Department of Physics, Mugla University, Mugla 48000 (Turkey); Onari, S. [Institute of Materials Science, University of Tsukuba 305-8573 (Japan)

2006-04-13T23:59:59.000Z

434

Preparation of GaAs photocathodes at low temperature  

SciTech Connect

The preparation of an atomically clean surface is a necessary step in the formation of negative electron affinity (NEA) GaAs. Traditional methods to this end include cleaving, heat cleaning and epitaxial growth. Cleaving has the advantage of yielding a fresh surface after each cleave, but is limited to small areas and is not suitable for specialized structures. Heat cleaning is both simple and highly successful, so it is used as a preparation method in virtually all laboratories employing a NEA source on a regular basis. Due to its high cost and complexity, epitaxial growth of GaAs with subsequent in vacuo transfer is not a practical solution for most end users of GaAs as a NEA electron source. While simple, the heating cleaning process has a number of disadvantages. Here, a variety of cleaning techniques related to preparation of an atomically clean GaAs surface without heating to 600 C are discussed and evaluated.

Mulhollan, G.; Clendenin, J.; Tang, H.

1996-10-01T23:59:59.000Z

435

HH5, Antiferromagnetic Interlayer Exchange Couplings in Ga  

Science Conference Proceedings (OSTI)

Author(s), Sun Jae Chung, Sanghoon Lee, Brian J. Kirby, Julie A. Borchers, ... LATE NEWS: KK3, Non-Catalytic Synthesis of GaN Nanostructures at Low ...

436

Micro Raman Spectroscopy of Annealed Erbium Implanted GaN  

E-Print Network (OSTI)

Wurtzite GaN epilayers grown by metal organic chemical vapor deposition on sapphire substrates were subsequently ion implanted with Er to a dose of 5×10ą? cm?˛. The implanted samples were annealed in nitrogen atmosphere ...

Vajpeyi, Agam P.

437

GaAs Films Prepared by RF-Magnetron Sputtering  

DOE Green Energy (OSTI)

The authors reported on the optical absorption, adhesion, and microstructure of RF-magnetron sputtered films of hydrogenated amorphous and microcrystalline GaAs films for the 1 to 25 {micro}m infrared wavelength rate. Sputtering parameters which were varied include sputtering power, temperature and pressure, and hydrogen sputtering-gas concentration. TEM results show a sharp transition from purely amorphous GaAs to a mixture of microcrystalline GaAs in an amorphous matrix at 34 {+-} 2 C. By optimizing the sputtering parameters, the optical absorption coefficient can be decreased below 100 cm{sup -1} for wavelengths greater than about 1.25 {micro}m. These results represent the lowest reported values of optical absorption for sputtered films of GaAs directly measured by spectrophotometry for the near-infrared wavelength region.

L.H. Ouyang; D.L. Rode; T. Zulkifli; B. Abraham-Shrauner; N. Lewis; M.R. Freeman

2001-08-01T23:59:59.000Z

438

Elba Island, GA Natural Gas Liquefied Natural Gas Imports from...  

U.S. Energy Information Administration (EIA) Indexed Site

Equatorial Guinea (Million Cubic Feet) Elba Island, GA Natural Gas Liquefied Natural Gas Imports from Equatorial Guinea (Million Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3...

439

Elba Island, GA Natural Gas Liquefied Natural Gas Imports from...  

U.S. Energy Information Administration (EIA) Indexed Site

Nigeria (Million Cubic Feet) Elba Island, GA Natural Gas Liquefied Natural Gas Imports from Nigeria (Million Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6...

440

Cathodoluminescence Microanalysis of Suspended GaN Nano ...  

Science Conference Proceedings (OSTI)

CL from bulk GaN is dominated by the ~3.4 eV near-band-edge emission. In contrast, the suspended nano-membranes emit a broad defect associated emission ...

Note: This page contains sample records for the topic "tn al ga" 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

Elba Island, GA Natural Gas Liquefied Natural Gas Imports from...  

Gasoline and Diesel Fuel Update (EIA)

Trinidad and Tobago (Million Cubic Feet) Elba Island, GA Natural Gas Liquefied Natural Gas Imports from Trinidad and Tobago (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul...

442

Elba Island, GA Natural Gas Liquefied Natural Gas Imports from...  

Gasoline and Diesel Fuel Update (EIA)

Egypt (Million Cubic Feet) Elba Island, GA Natural Gas Liquefied Natural Gas Imports from Egypt (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2011 5,780...

443

Elba Island, GA Liquefied Natural Gas Total Imports (Million...  

U.S. Energy Information Administration (EIA) Indexed Site

Liquefied Natural Gas Total Imports (Million Cubic Feet) Elba Island, GA Liquefied Natural Gas Total Imports (Million Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5...

444

Modeling of InGaSb thermophotovoltaic cells and materials  

DOE Green Energy (OSTI)

A closed form computer program has been developed for the simulation and optimization of In{sub x}Ga{sub 1{minus}x}Sb thermophotovoltaic cells operating at room temperature. The program includes material parameter models of the energy bandgap, optical absorption constant, electron and hole mobility, intrinsic carrier concentration and index of refraction for any composition of GaInSb alloys.

Zierak, M.; Borrego, J.M.; Bhat, I.; Gutmann, R.J. [Rensselaer Polytechnic Inst., Troy, NY (United States); Charache, G. [Lockheed Martin, Inc., Schenectady, NY (United States)

1997-05-01T23:59:59.000Z

445

SEU design consideration for MESFETs on LT GaAs  

SciTech Connect

Computer simulation results are reported on transistor design and single-event charge collection modeling of metal-semiconductor field effect transistors (MESFETs) fabricated in the Vitesse H-GaAsIII{reg_sign} process on Low Temperature grown (LT) GaAs epitaxial layers. Tradeoffs in Single Event Upset (SEU) immunity and transistor design are discussed. Effects due to active loads and diffusion barriers are examined.

Weatherford, T.R.; Radice, R.; Eskins, D. [Naval Postgraduate School, Monterey, CA (United States)] [and others

1997-12-01T23:59:59.000Z

446

Influence of defect formation as a result of incorporation of a Mn {delta} layer on the photosensitiviy spectrum of InGaAs/GaAs quantum wells  

Science Conference Proceedings (OSTI)

The influence of defect formation upon the deposition of a Mn {delta} layer and a GaAs coating layer (with the use of laser evaporation) on the photosensitivity spectra of heterostructures with InGaAs/GaAs quantum wells located in the near-surface region has been studied.

Gorshkov, A. P., E-mail: gorskovap@phys.unn.ru; Karpovich, I. A.; Pavlova, E. D.; Kalenteva, I. L. [Lobachevsky State University of Nizhny Novgorod (Russian Federation)

2012-02-15T23:59:59.000Z

447

Influence of the adatom diffusion on selective growth of GaN nanowire regular arrays  

Science Conference Proceedings (OSTI)

Molecular beam epitaxy (MBE) on patterned Si/AlN/Si(111) substrates was used to obtain regular arrays of uniform-size GaN nanowires (NWs). The silicon top layer has been patterned with e-beam lithography, resulting in uniform arrays of holes with different diameters (d{sub h}) and periods (P). While the NW length is almost insensitive to the array parameters, the diameter increases significantly with d{sub h} and P till it saturates at P values higher than 800 nm. A diffusion induced model was used to explain the experimental results with an effective diffusion length of the adatoms on the Si, estimated to be about 400 nm.

Gotschke, T.; Schumann, T.; Limbach, F.; Calarco, R. [Institute of Bio- and Nanosystems (IBN-1), Research Centre Juelich GmbH and JARA-Fundamentals of Future Information Technology (FIT), 52425 Juelich (Germany); Paul-Drude-Institut fuer Festkoerperelektronik, Hausvogteiplatz 5-7, 10117 Berlin (Germany); Stoica, T. [Institute of Bio- and Nanosystems (IBN-1), Research Centre Juelich GmbH and JARA-Fundamentals of Future Information Technology (FIT), 52425 Juelich (Germany)

2011-03-07T23:59:59.000Z

448

Realization of high-quality HfO{sub 2} on In{sub 0.53}Ga{sub 0.47}As by in-situ atomic-layer-deposition  

Science Conference Proceedings (OSTI)

High {kappa} dielectric of HfAlO/HfO{sub 2} was an in-situ atomic-layer-deposited directly on molecular beam epitaxy grown In{sub 0.53}Ga{sub 0.47}As surface without using pre-treatments or interfacial passivation layers, where HfAlO (HfO{sub 2}:Al{sub 2}O{sub 3} {approx} 4:1) with high re-crystallization temperature was employed as the top oxide layer. The HfAlO ({approx}4.5 nm)/HfO{sub 2} (0.8 nm)/In{sub 0.53}Ga{sub 0.47}As metal oxide semiconductor capacitors have exhibited an oxide/In{sub 0.53}Ga{sub 0.47}As interface free of arsenic-related defective bonding, thermodynamic stability at 800 deg. C, and low leakage current densities of oxide thickness of less than 1 nm has been achieved by reducing the HfAlO thickness to {approx}2.7 nm with the same initial HfO{sub 2} thickness of {approx}0.8 nm.

Lin, T. D.; Hong, M. [Graduate Institute of Applied Physics and Department of Physics, National Taiwan University, Taipei 10617, Taiwan (China); Chang, Y. H. [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Lin, C. A.; Huang, M. L.; Lee, W. C. [Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Kwo, J. [Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Center for Condensed Matter Sciences, National Taiwan University, Taipei 10617, Taiwan (China)

2012-04-23T23:59:59.000Z

449

Optical anisotropy of GaSb type-II nanorods on vicinal (111)B GaAs  

SciTech Connect

We form self-assembled GaSb type-II nanorods on a vicinal (111)B GaAs substrate by molecular beam epitaxy and study their optical anisotropy. The GaSb nanorods are elongated and aligned along the [-1 0 1] direction, where the average length, width, and height are about 84, 30, and 2.5 nm. In polarized photoluminescence (PL) measurements, the peak of the GaSb nanorods is observed at about 1.1 eV, where the PL intensity is largest for the [-1 0 1] polarization and smallest for the polarization perpendicular to it. The degree of polarization is more than 20% and depends on the recombination energy. By comparing with a theoretical model based on 4 x 4 Luttinger-Kohn Hamiltonian, we find that the experimental results are explained by considering the Sb/As inter-diffusion and the nanorod height distribution.

Kawazu, Takuya; Noda, Takeshi; Mano, Takaaki; Sakuma, Yoshiki [National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Akiyama, Yoshihiro [Toyota Technological Institute, 2-12-1 Hisakata, Tempaku-ku, Nagoya (Japan); Sakaki, Hiroyuki [National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Toyota Technological Institute, 2-12-1 Hisakata, Tempaku-ku, Nagoya (Japan)

2011-12-05T23:59:59.000Z

450

EE9, MBE Grown InGaAsSbN/GaSb Single Quantum Wells for Mid ...  

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 ...

451

Mechanism for radiative recombination and defect properties of GaP/GaNP core/shell nanowires  

SciTech Connect

Recombination processes in GaP/GaNP core/shell nanowires (NWs) grown on a Si substrate by molecular beam epitaxy are examined using a variety of optical characterization techniques, including cw- and time-resolved photoluminescence and optically detected magnetic resonance (ODMR). Superior optical quality of the structures is demonstrated based on the observation of intense emission from a single NW at room temperature. This emission is shown to originate from radiative transitions within N-related localized states. From ODMR, growth of GaP/GaNP NWs is also found to facilitate formation of complex defects containing a P atom at its core that act as centers of competing non-radiative recombination.

Dobrovolsky, A.; Stehr, J. E.; Chen, S. L.; Chen, W. M.; Buyanova, I. A. [Department of Physics, Chemistry and Biology, Linkoeping University, S-581 83 Linkoeping (Sweden); Kuang, Y. J. [Department of Physics, University of California, La Jolla, California 92093 (United States); Sukrittanon, S. [Graduate Program of Materials Science and Engineering, La Jolla, California 92093 (United States); Tu, C. W. [Department of Electrical and Computer Engineering, University of California, La Jolla, California 92093 (United States)

2012-10-15T23:59:59.000Z

452

JJ1, Internal Quantum Efficiency of Polar and Non-Polar GaInN/GaN ...  

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 ...

453

Reducing the efficiency droop by lateral carrier confinement in InGaN/GaN quantum-well nanorods  

E-Print Network (OSTI)

Efficiency droop is a major obstacle facing high-power application of InGaN/GaN quantum-well (QW) light-emitting diodes. In this letter, we report the suppression of efficiency droop induced by density-activated defect recombination in nanorod structure of a-plane InGaN/GaN QWs. In the high carrier density regime, the retained emission efficiency in a dry-etched nanorod sample is observed to be over two times higher than that in its parent QW sample. We further argue that the improvement is a combined effect of the amendment contributed by lateral carrier confinement and the deterioration made by surface trapping.

Shi, Chentian; Yang, Fan; Park, Min Joo; Kwak, Joon Seop; Jung, Sukkoo; Choi, Yoon-Ho; Wang, Xiaoyong; Xiao, Min

2013-01-01T23:59:59.000Z

454

Catalytic Effect of Ti for Hydrogen Cycling in NaAlH4  

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

Effect of Ti for Effect of Ti for Hydrogen Cycling in NaAlH 4 Mei-Yin Chou School of Physics Georgia Institute of Technology (DE-FG02-05ER46229) Acknowledgment: Yan Wang, Roland Stumpf Why is NaAlH 4 interesting? A viable candidate for hydrogen-storage material: High theoretical weight-percent hydrogen content of 5.55% and low cost But (before 1997) Dehydrogenation occurs at high temperature; rehydrogenation is difficult. Bogdanovic and Schwickardi, 1997 Hydrogen can be reversibly absorbed and desorbed from NaAlH 4 under moderate conditions by the addition of catalysts (compounds containing Ti, Zr, etc.) High Hydrogen Contents in Complex Hydrides Hydride wt% Hydride wt% Be(BH 4 ) 2 20.8 Mg(AlH 4 ) 2 9.3 LiBH 4 18.2 Ca(AlH 4 ) 2 7.9 Mg(BH 4 ) 2 14.9 KBH 4 7.5 Ca(BH 4 ) 2 11.6 NaAlH 4 7.5 NaBH4 10.7 Ga(AlH

455

Elimination of charge-enhancement effects in GaAs FETs with a low-temperature grown GaAs buffer layer  

Science Conference Proceedings (OSTI)

The use of low temperature grown GaAs (LT GaAs) buffer layer in GaAs FETs is shown via computer simulation and experimental measurement to reduce ion-induced charge collection by two to three orders of magnitude. This reduction in collected charge is associated with the efficient reduction of charge-enhancement mechanisms in the FETs. Error rate calculations indicate that the soft error rate of LT GaAs integrated circuits will be reduced by several orders of magnitude when compared to conventional FET-based GaAs ICs.

McMorrow, D.; Weatherford, T.R.; Curtice, W.R.; Knudson, A.R.; Buchner, S.; Melinger, J.S.; Tran, L.H.; Campbell, A.B. [Naval Research Lab., Washington, DC (United States)

1995-12-01T23:59:59.000Z

456

Active region based on graded-gap InGaN/GaN superlattices for high-power 440- to 470-nm light-emitting diodes  

SciTech Connect

The structural and optical properties of light-emitting diode structures with an active region based on ultrathin InGaN quantum wells limited by short-period InGaN/GaN superlattices from both sides have been investigated. The dependences of the external quantum efficiency on the active region design are analyzed. It is shown that the use of InGaN/GaN structures as limiting graded-gap short-period superlattices may significantly increase the quantum efficiency.

Tsatsulnikov, A. F., E-mail: Andrew@beam.ioffe.ru; Lundin, W. V.; Sakharov, A. V.; Zavarin, E. E.; Usov, S. O.; Nikolaev, A. E.; Cherkashin, N. A.; Ber, B. Ya.; Kazantsev, D. Yu. [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation); Mizerov, M. N. [Russian Academy of Sciences, Center for Microelectronics, Ioffe Physicotechnical Institute (Russian Federation); Park, Hee Seok [Samsung Electro-Mechanics Co. Ltd. (Korea, Republic of); Hytch, M.; Hue, F. [National Center for Scientific Research, Center for Material Elaboration and Structural Studies (France)

2010-01-15T23:59:59.000Z

457

High Voltage GaN Schottky Rectifiers  

SciTech Connect

Mesa and planar GaN Schottky diode rectifiers with reverse breakdown voltages (V{sub RB}) up to 550V and >2000V, respectively, have been fabricated. The on-state resistance, R{sub ON}, was 6m{Omega}{center_dot} cm{sup 2} and 0.8{Omega}cm{sup 2}, respectively, producing figure-of-merit values for (V{sub RB}){sup 2}/R{sub ON} in the range 5-48 MW{center_dot}cm{sup -2}. At low biases the reverse leakage current was proportional to the size of the rectifying contact perimeter, while at high biases the current was proportional to the area of this contact. These results suggest that at low reverse biases, the leakage is dominated by the surface component, while at higher biases the bulk component dominates. On-state voltages were 3.5V for the 550V diodes and {ge}15 for the 2kV diodes. Reverse recovery times were <0.2{micro}sec for devices switched from a forward current density of {approx}500A{center_dot}cm{sup -2} to a reverse bias of 100V.

CAO,X.A.; CHO,H.; CHU,S.N.G.; CHUO,C.-C.; CHYI,J.-I.; DANG,G.T.; HAN,JUNG; LEE,C.-M.; PEARTON,S.J.; REN,F.; WILSON,R.G.; ZHANG,A.P.

1999-10-25T23:59:59.000Z

458

Testing of ethylene propylene seals for the GA-4/GA-9 casks  

SciTech Connect

The primary O-ring seal of the GA-4 and GA-9 casks was tested for leakage with a full-scale mockup of the cask lid and flange. Tests were performed at temperatures of ambient, {minus}41{degrees}, 121{degrees}, and 193{degrees}C. Shim plates between the lid and flange simulated gaps caused by thermal distortion. The testing used a helium mass spectrometer leak detector (MSLD). Results showed that the primary seal was leaktight for all test conditions. Helium permeation through the seal began in 13--23 minutes for the ambient tests and in 1--2 minutes for the tests at elevated temperatures. After each test several hours of the pumping were typically required to reduce the MSLD background reading to an acceptable level for the next test, indicating that the seal had become saturated with helium. To verify that the test results showed permeation and not real leakage, several response checks were conducted in which a calibrated leak source was inserted in the detector line near the seal. When the leak source was activated the detector responded within seconds.

Boonstra, R.H.

1993-08-01T23:59:59.000Z

459

AL PRO | Open Energy Information  

Open Energy Info (EERE)

AL PRO AL PRO Jump to: navigation, search Name AL-PRO Place Grossheide, Lower Saxony, Germany Zip 26532 Sector Wind energy Product AL-PRO is an inndependent expert office for wind forecasts, wind potential studies, turbulence inquiries, visualizations as well as sound and shade throw forecasts Coordinates 53.592743°, 7.34313° 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":53.592743,"lon":7.34313,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

460

Nanostructuring of silicon substrates for the site-controlled growth of GaAs/In0.15Ga0.85As/GaAs nanostructures  

Science Conference Proceedings (OSTI)

We report the optimization of electron beam lithography and inductively coupled plasma (ICP) dry etching processes to fabricate pre-patterned Si (100) substrates with sub-100nm holes with controlled size and shape. An efficient in situ cleaning sequence ... Keywords: Electron beam lithography, ICP dry etching, InGaAs quantum dots, MBE growth, Nanostructuring of silicon

Muhammad Usman; Tariq Alzoubi; Mohamed Benyoucef; Johann Peter Reithmaier

2012-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "tn al ga" 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

Cerenkov-type phase-matched second-harmonic emission from GaAs/AlGaAs quantum-cascade lasers  

SciTech Connect

Second-harmonic (SH) emission in the form of Cerenkov-type phase-matched radiation has been measured for quantum-cascade lasers (QCLs) with built-in nonlinearities. The QCLs operate at 10.9 {mu}m wavelength and, due to material dispersion, show a high collinear phase mismatch, resulting in low SH external conversion efficiencies on the order of 2 {mu}W/W{sup 2}. Due to our waveguide design, we were able to couple out and measure the generated SH light in the form of Cerenkov-type phase-matched radiation from the substrate of the device. The SH power collected from the Cerenkov beam leads to an increased external conversion efficiency of {approx}50 {mu}W/W{sup 2}.

Austerer, M.; Detz, H.; Schartner, S.; Nobile, M.; Schrenk, W.; Andrews, A. M.; Klang, P. [Center for Micro- and Nanostructures, TU Vienna, Floragasse 7, A-1040 Vienna (Austria); Strasser, G. [Departments of Electrical Engineering and Physics, SUNY at Buffalo, New York 14260 (United States)

2008-03-17T23:59:59.000Z

462

Cross-plane lattice and electronic thermal conductivities of ErAs : InGaAs/InGaAlAs superlattices  

E-Print Network (OSTI)

should be noted that the lattice thermal conductivity should88, 242107 ?2006? Cross-plane lattice and electronic thermalWe studied the cross-plane lattice and electronic thermal

2006-01-01T23:59:59.000Z

463

Light extraction in individual GaN nanowires on Si for LEDs  

E-Print Network (OSTI)

GaN-based nanowires hold great promise for solid state lighting applications because of their waveguiding properties and the ability to grow nonpolar GaN nanowire-based heterostructures, which could lead to increased light ...

Zhou, Xiang

464

High electron mobility in Ga(In)NAs films grown by molecular beam epitaxy  

Science Conference Proceedings (OSTI)

We report the highest mobility values above 2000 cm{sup 2}/Vs in Si doped GaNAs film grown by molecular beam epitaxy. To understand the feature of the origin which limits the electron mobility in GaNAs, temperature dependences of mobility were measured for high mobility GaNAs and referential low mobility GaInNAs. Temperature dependent mobility for high mobility GaNAs is similar to the GaAs case, while that for low mobility GaInNAs shows large decrease in lower temperature region. The electron mobility of high quality GaNAs can be explained by intrinsic limiting factor of random alloy scattering and extrinsic factor of ionized impurity scattering.

Miyashita, Naoya; Ahsan, Nazmul; Monirul Islam, Muhammad; Okada, Yoshitaka [Research Center for Advanced Science and Technology (RCAST), The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904 (Japan); Inagaki, Makoto [Toyota Technological Institute, 2-12-1 Hisakata, Tempaku-ku, Nagoya 468-8511, Aichi (Japan); Yamaguchi, Masafumi [Research Center for Advanced Science and Technology (RCAST), The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904 (Japan); Toyota Technological Institute, 2-12-1 Hisakata, Tempaku-ku, Nagoya 468-8511, Aichi (Japan)

2012-11-26T23:59:59.000Z

465

Soham Al Snih Al Snih, MD., PhD. Curriculum Vitae CURRICULUM VITAE  

E-Print Network (OSTI)

Soham Al Snih Al Snih, MD., PhD. Curriculum Vitae 1 CURRICULUM VITAE NAME: Soham Al Snih Al Snih, M at the Sealy Center on Aging, University of Texas Medical Branch, Galveston, TX. #12;Soham Al Snih Al Snih, MD arthritis. B. Grant Support Current Grant Support: 1R03 AG029959-01A2 (Al Snih ­PI) Period: 06

Wood, James B.

466

On the Security of Liaw et al.'s Scheme  

E-Print Network (OSTI)

Recently, Liaw et al. proposed a remote user authentication scheme using smartcards. They claimed a number of features of their scheme, e.g. a dictionary of verification tables is not required to authenticate users; users can choose their password freely; mutual authentication is provided between the user and the remote system; the communication cost and the computational cost are very low; users can update their password after the registration phase; a session key agreed by the user and the remote system is generated in every session; and the nonce-based scheme which does not require a timestamp (to solve the serious time synchronization problem) etc. In this paper We show that Liaw et al.'s scheme does not stand with various security requirements and is completely insecure. Keywords: Authentication, Smartcards, Remote system, Attack.

Awasthi, Amit K

2008-01-01T23:59:59.000Z

467

SLAC_TN04051_04.dvi  

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

issue is that of energy deposition in the issue is that of energy deposition in the conversion target and the comparison of the induced stress with the ultimate tensile strength of the target material. Since the length of the incident beam pulse is large in comparison to the ratio of beam size to the speed of sound, the concurrent pressure pulse dissipates in a time short compared to the overall pulse duration and one is left with only the Abstract: The effects of electron conditioning on commercially prepared aluminum alloys 1100 and 6063 were investigated. Contrary to the assumption that electron conditioning, if performed long enough, can reduce and stabilize the SEY at approximately 1.1, the SEY of aluminum did not go lower than 1.8. In fact, it increases again with continued electron exposure dose.

468

TN 1421 - Chapter 2: Electrical Substitution Radiometry  

Science Conference Proceedings (OSTI)

... II. Electrical Substitution Radiometry. ... Figure 1. Schematic diagram of the essential components of an electrical substitution radiometer. ...

469

ORNL/TN--8524 DE83 005172  

E-Print Network (OSTI)

-kW Free-Piston Stirling Engine with a Dashpot Load DISCLAIMER This report was prepared as an account RESULTS AND DESCRIPTION OF A 1KW FREE-PISTON STIRLING ENGINE WITH A DASHPOT LOAD Jeffrey Schreiber.33 hp) single cylinder free-piston Stirling engine was installed in the test facilities at the Lewis

Oak Ridge National Laboratory

470

Black-body radiation shift of the Ga$^{+}$ clock transition  

E-Print Network (OSTI)

The blackbody radiation shift of the Ga$^+$ $4s^2 \\ ^1S^e_0 \\to 4s4p \\ ^3P^o_0$ clock transition is computed to be $-$$0.0140 \\pm 0.0048$ Hz at 300 K. The small shift is consistent with the blackbody shifts of the clock transitions of other group III ions which are of a similar size. The polarizabilities of the Ga$^+$ $4s^2 \\ ^1S^e_0$, $4s4p \\ ^3P^o_0$, and $4s4p \\ ^1P^o_1$ states were computed using the configuration interaction method with an underlying semi-empirical core potential. A byproduct of the analysis involved large scale calculations of the low lying spectrum and oscillator strengths of the Ga$^{2+}$ ion.

Cheng, Yongjun

2013-01-01T23:59:59.000Z

471

Aug. 8-9, 2006 HAPL meeting, GA Open Discussion on Advanced Armor  

E-Print Network (OSTI)

Aug. 8-9, 2006 HAPL meeting, GA 1 Open Discussion on Advanced Armor Concepts Moderated by A. René in case the W armor does not work. #12;Aug. 8-9, 2006 HAPL meeting, GA 3 Roman Aquaduct at Pont du Gard, Provence #12;Aug. 8-9, 2006 HAPL meeting, GA 4 Possible Advanced Armor Options Include: · Engineered

Raffray, A. René

472

Current injection efficiency of InGaAsN quantum-well lasers Nelson Tansua  

E-Print Network (OSTI)

Current injection efficiency of InGaAsN quantum-well lasers Nelson Tansua Department of Electrical-threshold current injection efficiency of quantum well QW lasers is clarified. The analysis presented here is applied to the current injection efficiency of 1200 nm emitting InGaAs and 1300 nm emitting InGaAsN QW

Gilchrist, James F.

473

ANN-based GA for generating the sizing curve of stand-alone photovoltaic systems  

Science Conference Proceedings (OSTI)

Recent advances in artificial intelligence techniques have allowed the application of such technologies in real engineering problems. In this paper, an artificial neural network-based genetic algorithm (ANN-GA) model was developed for generating the ... Keywords: ANN, ANN-GA, GA, Prediction, Sizing curve, Stand-alone PV system

Adel Mellit

2010-05-01T23:59:59.000Z

474

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

475

TESLA-FEL 2007-03 Application of low cost GaAs LED as neutron  

E-Print Network (OSTI)

neutrons in unbiased Gallium Arsenide (GaAs) Light Emitting Diodes (LED) resulted in a reduction Keywords: COTS components, Displacement damage, Electron Linear Accelerator, GaAs Light emitting diode (LED) Gallium Arsenide (GaAs) light emitting diode (LED) for the assessment of integrated neutron fluence

476

Vertically aligned GaN nanotubes - Fabrication and current image analysis  

Science Conference Proceedings (OSTI)

In this work, we present a one step formation method of nanotubes on GaN film, and then map out local current of nanotubes. GaN nanotubes were formed by inductively coupled plasma (ICP) etching and found that tops of these nanotubes were hexagonal with ... Keywords: C-AFM, FESEM, GaN, ICP, Nanotubes

Shang-Chao Hung; Yan-Kuin Su; Shoou-Jinn Chang; Y. H. Chen

2006-11-01T23:59:59.000Z

477

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 ...

478

GA Hot Cell D&D Closeout Report  

Office of Legacy Management (LM)

GENERAL ATOMICS GENERAL ATOMICS HOT CELL FACILITY DECONTAMINATION & DECOMMISSIONING PROJECT FINAL PROJECT CLOSEOUT REPORT prepared for GA HOT CELL D&D PROJECT CONTRACT NUMBERS DE-AC03-84SF11962 and DE-AC03-95SF20798 PBS VL-GA-0012 Approvals Prepared by: James Davis, III Date Project Manager, Oakland Environmental Programs Office Reviewed by: John Lee Date Deputy, Oakland Environmental Programs Office Approved by: Laurence McEwen Date Acting Director, Oakland Environmental Programs Office General Atomics Hot Cell Facility D&D Project Closeout Report Contents Page i CONTENTS CONTENTS.....................................................................................................................................

479

Epitaxial EuO thin films on GaAs  

SciTech Connect

We demonstrate the epitaxial growth of EuO on GaAs by reactive molecular beam epitaxy. Thin films are grown in an adsorption-controlled regime with the aid of an MgO diffusion barrier. Despite the large lattice mismatch, it is shown that EuO grows well on MgO(001) with excellent magnetic properties. Epitaxy on GaAs is cube-on-cube and longitudinal magneto-optic Kerr effect measurements demonstrate a large Kerr rotation of 0.57 deg., a significant remanent magnetization, and a Curie temperature of 69 K.

Swartz, A. G.; Ciraldo, J.; Wong, J. J. I.; Li Yan; Han Wei; Lin Tao; Shi, J.; Kawakami, R. K. [Department of Physics and Astronomy, University of California, Riverside, California 92521 (United States); Mack, S.; Awschalom, D. D. [Center for Spintronics and Quantum Computation, University of California, Santa Barbara, California 93106 (United States)

2010-09-13T23:59:59.000Z

480

Simple intrinsic defects in GaAs : numerical supplement.  

SciTech Connect

This Report presents numerical tables summarizing properties of intrinsic defects in gallium arsenide, GaAs, as computed by density functional theory. This Report serves as a numerical supplement to the results published in: P.A. Schultz and O.A. von Lilienfeld, 'Simple intrinsic defects in GaAs', Modelling Simul. Mater. Sci Eng., Vol. 17, 084007 (2009), and intended for use as reference tables for a defect physics package in device models. The numerical results for density functional theory calculations of properties of simple intrinsic defects in gallium arsenide are presented.

Schultz, Peter Andrew

2012-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "tn al ga" 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.


481

Electron Hall Mobility in GaAsBi  

Science Conference Proceedings (OSTI)

We present measurements of the electron Hall mobility in n-type GaAs{sub 1-x}Bi{sub x} epilayers. We observed no significant degradation in the electron mobility with Bi incorporation in GaAs, up to a concentration of 1.2%. At higher Bi concentration ({ge} 1.6%) some degradation of the electron mobility was observed, although there is no apparent trend. Temperature dependent Hall measurements of the electron mobility suggest neutral impurity scattering to be the dominant scattering mechanism.

Kini, R. N.; Bhusal, L.; Ptak, A. J.; France, R.; Mascarenhas, A.

2009-01-01T23:59:59.000Z

482

Analyzing the growth of In{sub x}Ga{sub 1-x}N/GaN superlattices in self-induced GaN nanowires by x-ray diffraction  

Science Conference Proceedings (OSTI)

Self-induced GaN nanowires are grown by plasma-assisted molecular beam epitaxy, with In{sub x}Ga{sub 1-x}N quantum wells inserted to form an axial superlattice. From the {omega}-2{theta} scans of a laboratory x-ray diffraction experiment, we obtain the superlattice period, the thickness of the quantum wells, and the In content in this layer. The axial growth rate of the In{sub x}Ga{sub 1-x}N quantum wells is significantly enhanced, which we attribute to increased Ga diffusion along the nanowire sidewalls in the presence of In.

Woelz, M.; Kaganer, V. M.; Brandt, O.; Geelhaar, L.; Riechert, H.

2011-06-27T23:59:59.000Z

483

Impact of superbends at the ALS  

E-Print Network (OSTI)

the prototype [2] . At the ALS injection is made off axis inField Bend Magnet for the ALS", in the Proceedings of theto zero. [5)At present the ALS operates with the dispersion

Nishmura, H.

2011-01-01T23:59:59.000Z

484

Compton Scattering in the ALS Booster  

E-Print Network (OSTI)

Compton Scattering in the ALS Booster D. Robin, C. Kim, and410 COMPTON SCATTERING IN THE ALS BOOSTER* D. Robin, C. Kim,COMPTON SCATTERING IN THE ALS BOOSTER* D. Robin, C. Kim, and

Robin, David

2008-01-01T23:59:59.000Z

485

Spin Spectrometer at the ALS and APS  

E-Print Network (OSTI)

5 Spin Spectrometer at the ALS and APS-NIM/SRI07 Figure 3 Ancollected on Beamline 7 at the ALS is shown here. The photonSpin Spectrometer at the ALS and APS-NIM/SRI07 Spin

Tobin, James G; Lawrence Livermore National Laboratory; University of Missouri-Rolla; Boyd Technologies

2008-01-01T23:59:59.000Z

486

DYNAMIC APERTURE OF THE ALS BOOSTER SYNCHROTRON  

E-Print Network (OSTI)

Nelson, "Magnetic Properties of the ALS noosler Synchrotron23,1989 Dynamic Aperture of the ALS Booster Synchrotron C.H.DYNAMIC APERTURE OF TIlE ALS BOOSTER SYNCIIROlRON· CharI""

Kim, C.H.

2010-01-01T23:59:59.000Z

487

17th Annual ALS Users' Association Meeting  

E-Print Network (OSTI)

Scientific Achievement at the ALS went to Andrea Cavalleri (with an art student's impression of the ALS (center) ;and ALS Acting Director Janos Kirz gave an overview of the

Robinson, Art; Tamura, Lori

2004-01-01T23:59:59.000Z