Sample records for tl uut ge

  1. Crystal structure, electronic structure and physical properties of the new low-valent thallium silicon telluride Tl{sub 6}Si{sub 2}Te{sub 6} in comparison to Tl{sub 6}Ge{sub 2}Te{sub 6}

    SciTech Connect (OSTI)

    Assoud, Abdeljalil [Department of Chemistry, University of Waterloo, Waterloo, Ont., N2L 3G1 (Canada); Soheilnia, Navid [Department of Chemistry, University of Waterloo, Waterloo, Ont., N2L 3G1 (Canada); Kleinke, Holger [Department of Chemistry, University of Waterloo, Waterloo, Ont., N2L 3G1 (Canada)]. E-mail: kleinke@uwaterloo.ca

    2006-08-15T23:59:59.000Z

    The title compounds were prepared from the elements in the stoichiometric ratio at 800deg. C under exclusion of air. Tl{sub 6}Si{sub 2}Te{sub 6} crystallizes in the space group P1-bar , isostructural with Tl{sub 6}Ge{sub 2}Te{sub 6}, with a=9.4235(6)A, b=9.6606(7)A, c=10.3889(7)A, {alpha}=89.158(2){sup o}, {beta}=96.544(2){sup o}, {gamma}=100.685(2){sup o}, V=923.3(1)A{sup 3} (Z=2). Its structure is composed of dimeric [Si{sub 2}Te{sub 6}]{sup 6-} units with a Si-Si single bond, while the Tl atoms are irregularly coordinated by five to six Te atoms. Numerous weakly bonding Tl-Tl contacts exist. Both title compounds are black semiconductors with small band gaps, calculated to be 0.9eV for Tl{sub 6}Si{sub 2}Te{sub 6} and 0.5eV for Tl{sub 6}Ge{sub 2}Te{sub 6}. The Seebeck coefficients are +65{mu}VK{sup -1} in case of Tl{sub 6}Si{sub 2}Te{sub 6} and +150{mu}VK{sup -1} in case of Tl{sub 6}Ge{sub 2}Te{sub 6} at 300K, and the electrical conductivities are 5.5 and 3{omega}{sup -1}cm{sup -1}, respectively.

  2. Type B epitaxy of Ge on CaF2(111) surface T.-L. Chan , C. Gaire, T.-M. Lu, G.-C. Wang, S.B. Zhang

    E-Print Network [OSTI]

    Wang, Gwo-Ching

    Type B epitaxy of Ge on CaF2(111) surface T.-L. Chan , C. Gaire, T.-M. Lu, G.-C. Wang, S.B. Zhang is rotated 180° about the [111] axis, dominated the heteroepitaxial growth of Ge(111) on a CaF2 theory to determine the energetics of the Ge(111)/CaF2(111) interface and found that the type B

  3. Tl

    Office of Legacy Management (LM)

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  4. Possible chiral bands in {sup 194}Tl

    SciTech Connect (OSTI)

    Masiteng, P. L.; Ramashidzha, T. M.; Maliage, S. M.; Sharpey-Schafer, J. F.; Vymers, P. A. [iThemba LABS, P.O Box 722, 7129 (South Africa); University of the Western Cape, Private Bag X17, 7535 Bellville (South Africa); Lawrie, E. A.; Lawrie, J. J.; Bark, R. A.; Mullins, S. M.; Murray, S. H. T. [iThemba LABS, P.O Box 722, 7129 (South Africa); Kau, J.; Komati, F. [iThemba LABS, P.O Box 722, 7129 (South Africa); University of the North West, Private Bag X2046, 2735 Mafikeng (South Africa); Lindsay, R. [University of the Western Cape, Private Bag X17, 7535 Bellville (South Africa); Matamba, I. [University of Venda for Science and Technology, Thohoyandou (South Africa); Mutshena, P. [iThemba LABS, P.O Box 722, 7129 (South Africa); University of Venda for Science and Technology, Thohoyandou (South Africa); Zhang, Y. [iThemba LABS, P.O Box 722, 7129 (South Africa); University of Cape Town, Private Bag, 7701 Rondebosch (South Africa)

    2011-10-28T23:59:59.000Z

    High spin states in {sup 194}Tl, excited through the {sup 181}Ta({sup 18}O,5n) fusion evaporation reaction, were studied using the AFRODITE array at iThemba LABS. Candidate chiral bands built on the {pi}h{sub 9/2} x {nu}i{sub 13/2}{sup 1} configuration were found. Furthermore these bands were observed through a band crossing caused by the excitation of a {nu}i{sub 13/2} pair. Above the band crossing the excitation energies remain close, suggesting that chirality may persist for the four quasiparticle configuration too.

  5. Shanghai TL Chemical Company | Open Energy Information

    Open Energy Info (EERE)

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  6. Diffusion in SiGe and Ge

    E-Print Network [OSTI]

    Liao, Christopher Yuan Ting

    2010-01-01T23:59:59.000Z

    Claeys, et al. , "Si versus Ge for future microelectronics,"in Selectively Doped Si/Si x Ge 1-x Superlattices," PhysicalA. Fitzgerald, et al. , "Relaxed Ge x Si 1-x structures for

  7. Diffusion in SiGe and Ge

    E-Print Network [OSTI]

    Liao, Christopher Yuan Ting

    2010-01-01T23:59:59.000Z

    High-electron-mobility Si/SiGe heterostructures: influenceof the relaxed SiGe buffer layer," Semiconductor Science andFrom its discovery to SiGe devices," Materials Science in

  8. Design Guidelines for Test Level 3 (TL-3) Through Test Level 5 (TL-5) Roadside Barrier Systems Placed on Mechanically Stabilized Earth (MSE) Retaining Wall

    E-Print Network [OSTI]

    Saez Barrios, Deeyvid 1980-

    2012-12-05T23:59:59.000Z

    DESIGN GUIDELINES FOR TEST LEVEL 3 (TL-3) THROUGH TEST LEVEL 5 (TL-5) ROADSIDE BARRIER SYSTEMS PLACED ON MECHANICALLY STABILIZED EARTH (MSE) RETAINING WALL A Dissertation by DEEYVID OSCAR SAEZ BARRIOS Submitted to the Office... ............................................................................................. 28 2.2.3 Full-Scale Crash Testing for TL-4 .............................................................. 32 2.2.4 Full-Scale Crash Testing for TL-5 .............................................................. 34 2.3 Background on Design Impact...

  9. Materials Data on Tl2Ge2S5 (SG:15) by Materials Project

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Kristin Persson

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  10. Materials Data on Tl2Ge2S5 (SG:15) by Materials Project

    SciTech Connect (OSTI)

    Kristin Persson

    2014-11-02T23:59:59.000Z

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  11. Preparation and characterization of TL-based superconducting thin films

    E-Print Network [OSTI]

    Wang, Pingshu

    1995-01-01T23:59:59.000Z

    of high Tc superconductors. . . . A. High superconducting transition temperature. B. Short coherence length. C. Large spatial anisotropy. D. Charge carriers. 2. Crystal structure. A. Ideal perovskite unit celL. B. Structure of Tl... perovskite unit cell, ABX3 Oxygen-deficient YBa2Cu307 8 structure . Crystal structure of T10 double layer compounds. . . . . . . . , . . . . . . . . . . . Crystal Structure of T10 monolayer compounds. . . . . . . . . . . . . . . . . . . . . . Schematic...

  12. Hidden Superlattice in Tl2(SC6H4S) and Tl2(SeC6H4Se) Solved from Powder X-ray Diffraction

    SciTech Connect (OSTI)

    K Stone; D Turner; M Singh; T Vaid; P Stephens

    2011-12-31T23:59:59.000Z

    The crystal structures of the isostructural title compounds poly[({mu}-benzene-1,4-dithiolato)dithallium], Tl{sub 2}(SC{sub 6}H{sub 4}S), and poly[({mu}-benzene-1,4-diselenolato)dithallium], Tl{sub 2}(SeC{sub 6}H{sub 4}Se), were solved by simulated annealing from high-resolution synchrotron X-ray powder diffraction. Rietveld refinements of an initial structure with one formula unit per triclinic cell gave satisfactory agreement with the data, but led to a structure with impossibly close non-bonded contacts. A disordered model was proposed to alleviate this problem, but an alternative supercell structure leads to slightly improved agreement with the data. The isostructural superlattice structures were confirmed for both compounds through additional data collection, with substantially better counting statistics, which revealed the presence of very weak superlattice peaks not previously seen. Overall, each structure contains Tl-S or Tl-Se two-dimensional networks, connected by phenylene bridges. The sulfur (or selenium) coordination sphere around each thallium is a highly distorted square pyramid or a 'see-saw' shape, depending upon how many Tl-S or Tl-Se interactions are considered to be bonds. In addition, the two compounds contain pairs of Tl{sup I} ions that interact through a closed-shell 'thallophilic' interaction: in the sulfur compound there are two inequivalent pairs of Tl atoms with Tl-Tl distances of 3.49 and 3.58 {angstrom}, while in the selenium compound those Tl-Tl interactions are at 3.54 and 3.63 {angstrom}.

  13. Plasma spectroscopic study of an electrodeless HID lamp containing Tl and Zn

    SciTech Connect (OSTI)

    Takeda, Mamoru; Horii, Shigeru; Hochi, Akira [Matsushita Electric Industrial Co., Ltd., Kyoto (Japan). Lighting Research Lab.

    1996-12-31T23:59:59.000Z

    Recently the electrodeless HID lamps excited by microwaves have been studied intensively. Tl is well known as a material having strong green emission lines. In this study, Tl spectra excited by microwaves were reported in the cases of Tl only and Tl + Zn. Using the Elenbaas`s method of high pressure Hg lamp, the cause of Tl continuous spectrum was examined. From the ratio of radiative intensities of two lines, an average arc temperature in the bulb was estimated. Then excitation level of the continuous emission spectrum near the 600nm wavelength was calculated from the dependence of the radiative intensities on these arc temperatures.

  14. CHEM 114 GE 124 MATH 110 GE 110 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120

    E-Print Network [OSTI]

    Saskatchewan, University of

    2006-07 CHEM 114 GE 124 MATH 110 GE 110 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120 GE 210 MATH 223CE 212 CMPT 116 Hum/SocSci Jr. GEOE 218 CE 225 MATH 224GE 213# GE 348# CE 295 English 11x# CE 315 CE 311 CE 318 CE 319 CE 317 CE 316CE 327 CE 321 Sr Sci elect#CE 329 CE 328 GE 300# Eng/Sr Sci Elec# CE Elec

  15. CHEM 114 GE 124 MATH 110 COMM 102GE 110 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120

    E-Print Network [OSTI]

    Saskatchewan, University of

    CHEM 114 GE 124 MATH 110 COMM 102GE 110 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120 CMPT 116CHEM 250# MATH 223 EE 201 GE 213 Grp. A elective*CHE 223 Hum/SocSci Jr. MATH 224 English 11x CHE 220CHE 210 CHECHE 413 Grp. B elective#* Grp. B elective*#CHE 424 CHE 421 CHE 422 GE 348# CHE 423 GE 449# CH E 470

  16. CHEM 114 GE 124 MATH 110 COMM 102GE 110 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120

    E-Print Network [OSTI]

    Saskatchewan, University of

    CHEM 114 GE 124 MATH 110 COMM 102GE 110 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120 CMPT 116CHEM 250# MATH 223 EE 201 GE 213 Grp. A elective*CHE 223 HSS@# MATH 224 English 11x CHE 220CHE 210 CHE 323 CHE Grp. B elective#* Grp. B elective*#CHE 424 CHE 421 CHE 422 GE 348# CHE 423 GE 449# CH E 470^ Chemical

  17. CHEM 114 GE 124 MATH 110 GE 110 COMM 102 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120

    E-Print Network [OSTI]

    Saskatchewan, University of

    CHEM 114 GE 124 MATH 110 GE 110 COMM 102 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120 ME 227 GE 213# MATH 223 EE 201ME 214 CMPT 116 ME 215 GE 226 MATH 224 Hum/SocSci@# ME 251 ME 229 ME 318 ME 335 ME 313 ME 316 ME 352ME 330 GE 348# ME 328 ME 327 ME 323 ME 321ME 324 RCM 300# ME 418 ME 417 ME 450 ME 431

  18. Pressure dependence of the superconducting critical temperature of Tl 2Ba 2Ca 2Cu 3O 10 y and Tl 2Ba 2Ca 3Cu 4O12 y up to 21 GPa

    E-Print Network [OSTI]

    Wijngaarden, Rinke J.

    Pressure dependence of the superconducting critical temperature of Tl 2Ba 2Ca 2Cu 3O 10 y and Tl 2 of the superconducting transition temperature Tc of Tl2Ba2Ca2Cu3O10 y Tl-2223 and Tl2Ba2Ca3Cu4O12 y Tl-2234 has been it is determined by that of the inner CuO2 layers. S0163-1829 96 07134-2 I. INTRODUCTION Superconductivity in high

  19. GE ?????????????????4G?????...

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    GE 4G Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new window) Click...

  20. AMENDMENT OF SOLICITATION/MODIFICA TlON OF CONTRACT

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    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del(ANL-IN-03-032)8Li (59AJ76) (See theDoctoral20ALSNews Vol. 364MODIFICA TlON OF

  1. GE Healthcare Introduction

    E-Print Network [OSTI]

    Lebendiker, Mario

    GE Healthcare Introduction HR 16 columns are designed for high resolution liquid chromatography your local GE Healthcare office. System compatibility HR 16 columns are designed to be used with ÄKTATM. Wash the parts thoroughly in distilled water. 4. Reassemble the column (see Assembling the column above

  2. Chevron, GE form Technology Alliance

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    form Technology Alliance February 3, 2014 HOUSTON, TX, Feb. 3, 2014-Chevron Energy Technology Company and GE Oil & Gas announced today the creation of the Chevron GE Technology...

  3. Backward electroproduction of pi0 mesons on protons in the region of nucleon resonances at four momentum transfer squared Q**2 = 1.0 GeV**2

    E-Print Network [OSTI]

    Laveissière, G; Jaminion, S; Jutier, C; Todor, L; Di Salvo, R; Van Hoorebeke, L; Alexa, L C; Anderson, B D; Aniol, K A; Arundell, K; Audit, G; Auerbach, L; Baker, F T; Baylac, M; Berthot, J; Bertin, P Y; Bertozzi, W; Bimbot, L; Böglin, W; Brash, E J; Breton, V; Breuer, H; Burtin, E; Calarco, J R; Cardman, L S; Cavata, C; Chang, C C; Chen, J P; Chudakov, E; Cisbani, E; Dale, D S; De Jager, C W; De Leo, R; Deur, A; D'Hose, N; Dodge, G E; Domingo, John J; Elouadrhiri, L; Epstein, M B; Ewell, L A; Finn, J M; Fissum, K G; Fonvieille, H; Fournier, G; Frois, B; Frullani, S; Furget, C; Gao, H; Gao, J; Garibaldi, F; Gasparian, A; Gilad, S; Gilman, R; Glamazdin, A; Glashausser, C; Gómez, J; Gorbenko, V; Grenier, P; Guichon, P A M; Hansen, J O; Holmes, R; Holtrop, M; Howell, C; Huber, G M; Hyde-Wright, C E; Incerti, S; Iodice, M; Jardillier, J; Jones, M K; Kahl, W; Kamalov, S; Kato, S; Katramatou, A T; Kelly, J J; Kerhoas, S; Ketikyan, A; Khayat, M; Kino, K; Kox, S; Kramer, L H; Kumar, K S; Kumbartzki, G; Kuss, M; Leone, A; Le Rose, J J; Liang, M; Lindgren, R A; Liyanage, N K; Lolos, G J; Lourie, R W; Madey, R; Maeda, K; Malov, S; Manley, D M; Marchand, C; Marchand, D; Margaziotis, D J; Markowitz, P; Marroncle, J; Martino, J; McCormick, K; McIntyre, J; Mehrabyan, S S; Merchez, F; Meziani, Z E; Michaels, R; Miller, G W; Mougey, J Y; Nanda, S K; Neyret, D; Offermann, E; Papandreou, Z; Perdrisat, C F; Perrino, R; Petratos, G G; Platchkov, S; Pomatsalyuk, R I; Prout, D L; Punjabi, V A; Pussieux, T; Quéméner, G; Ransome, R D; Ravel, O; Real, J S; Renard, F; Roblin, Y; Rowntree, D; Rutledge, G; Rutt, P M; Saha, A; Saitô, T; Sarty, A J; Serdarevic, A; Smith, T; Smirnov, G; Soldi, K; Sorokin, P; Souder, P A; Suleiman, R; Templon, J A; Terasawa, T; Tiator, L; Tieulent, R; Tomasi-Gustafsson, E; Tsubota, H; Ueno, H; Ulmer, P E; Urciuoli, G M; Van De Vyver, R; Van, R L J; der Meer; Vernin, P; Vlahovic, B; Voskanyan, H; Voutier, E; Watson, J W; Weinstein, L B; Wijesooriya, K; Wilson, R; Wojtsekhowski, B B; Zainea, D G; Zhang, W M; Zhao, J; Zhou, Z L

    2004-01-01T23:59:59.000Z

    Backward exclusive electroproduction of pi0 mesons on protons has been measured at Q**2 = 1.0 GeV**2 by detecting protons in the forward direction in coincidence with scattered electrons from the 4 GeV electron beam in Jefferson Lab's Hall A. The data span the range of the total (gamma* p) center-of-mass energy W from the pion production threshold to W = 2.0 GeV. The azimuthally separated differential cross sections sigma_T + epsilon * sigma_L, sigma_TL, and sigma_TT from this experiment are presented together with the MAID2000 and SAID parametrizations.

  4. Cosmogenic radionuclide production in NaI(Tl) crystals

    E-Print Network [OSTI]

    J. Amaré; S. Cebrián; C. Cuesta; E. García; C. Ginestra; M. Martínez; M. A. Oliván; Y. Ortigoza; A. Ortiz de Solórzano; C. Pobes; J. Puimedón; M. L. Sarsa; J. A. Villar; P. Villar

    2015-01-16T23:59:59.000Z

    The production of long-lived radioactive isotopes in materials due to the exposure to cosmic rays on Earth surface can be an hazard for experiments demanding ultra-low background conditions, typically performed deep underground. Production rates of cosmogenic isotopes in all the materials present in the experimental set-up, as well as the corresponding cosmic rays exposure history, must be both well known in order to assess the relevance of this effect in the achievable sensitivity of a given experiment. Although NaI(Tl) scintillators are being used in experiments aiming at the direct detection of dark matter since the first nineties of the last century, very few data about cosmogenic isotopes production rates have been published up to date. In this work we present data from two 12.5 kg NaI(Tl) detectors, developed in the frame of the ANAIS project, which were installed inside a convenient shielding at the Canfranc Underground Laboratory just after finishing surface exposure to cosmic rays. The very fast start of data taking allowed to identify and quantify isotopes with half-lives of the order of tens of days. Initial activities underground have been measured and then production rates at sea level have been estimated following the history of detectors; values of about a few tens of nuclei per kg and day for Te isotopes and 22Na and of a few hundreds for I isotopes have been found. These are the first direct estimates of production rates of cosmogenic nuclides in NaI crystals. A comparison of the so deduced rates with calculations using typical cosmic neutron flux at sea level and a carefully selected description of excitation functions will be also presented together with an estimate of the corresponding contribution to the background at low and high energies, which can be relevant for experiments aiming at rare events searches.

  5. GE Global Research Locations | GE Global Research

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  6. GE Global Research Leadership | GE Global Research

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    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) Environmental AssessmentsGeoffrey Campbell is theOpportunitiesTheGAOHome >About GE

  7. GE Researcher Discusses Leadership | GE Global Research

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    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist.Newof EnergyFunding OpportunityF G F ! ( ! ( ! ( !ProgressGE

  8. Electrocatalytic Dioxygen Reduction on Underpotentially Deposited Tl on Au(111) Studied by an Active Site Blocking

    E-Print Network [OSTI]

    Kwak, Juhyoun

    to those related to corrosion and metal-air batteries. Consequently, dioxygen reduction has been well (upd) process.4,8 There are several upd metals including Bi, Pb, and Tl on Au(111), which are known

  9. Thermoelectric properties of nanoporous Ge

    E-Print Network [OSTI]

    Lee, Joo-Hyoung

    We computed thermoelectric properties of nanoporous Ge (np-Ge) with aligned pores along the [001] direction through a combined classical molecular dynamics and first-principles electronic structure approach. A significant ...

  10. GE Anna Heijbel / The Storm

    E-Print Network [OSTI]

    Tian, Weidong

    1 / GE Anna Heijbel / The Storm® Confocal Optics 50, 100, 200 µm 5 IQTL · ·DNA ·DNA Gels, blots, tissue sections (not in situ), radio-TLC & X-Ray diffraction #12;2 / GE Anna Heijbel / Phosphor µm 1010 43 x 35 cm43 x 35 cm Scanning Technology #12;3 / GE Anna Heijbel / Confocal Optics PMTPMT

  11. HSE 1 HSE 2 HSE 3 GE 1 GE 2 GE 3 Residual effects of Large Vessels in GE BOLD Differential Mapping of Ocular Dominance Columns

    E-Print Network [OSTI]

    HSE 1 HSE 2 HSE 3 GE 1 GE 2 GE 3 Residual effects of Large Vessels in GE BOLD Differential Mapping these techniques in humans. Previous human studies (4-6) instead used the conventional GE BOLD technique, combined and limitations of GE BOLD differential mapping as compared to HSE BOLD differential mapping of ocular dominance

  12. Characteristics of Sn segregation in Ge/GeSn heterostructures

    SciTech Connect (OSTI)

    Li, H.; Chang, C.; Chen, T. P.; Cheng, H. H., E-mail: hhcheng@ntu.edu.tw [Center for Condensed Matter Sciences and Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Shi, Z. W.; Chen, H. [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

    2014-10-13T23:59:59.000Z

    We report an investigation of Sn segregation in Ge/GeSn heterostructures occurred during the growth by molecular beam epitaxy. The measured Sn profile in the Ge layer shows that: (a) the Sn concentration decreases rapidly near the Ge/GeSn interface, and (b) when moving away from the interface, the Sn concentration reduced with a much slower rate. The 1/e decay lengths of the present system are much longer than those of the conventional group IV system of Ge segregation in the Si overlayer because of the smaller kinetic potential as modeled by a self-limited two-state exchange scheme. The demonstration of the Sn segregation shows the material characteristics of the heterostructure, which are needed for the investigation of its optical properties.

  13. Band structures and intruder $?$$i_{13/2}$ state in $^{197}$Tl

    E-Print Network [OSTI]

    H. Pai; G. Mukherjee; S. Bhattacharya; C. Bhattacharya; S. Bhattacharyya; T. Bhattacharjee; S. Chanda; S. Rajbanshi; A. Goswami; M. R. Gohil; S. Kundu; T. K. Ghosh; K. Banerjee; T. K. Rana; R. Pandey; G. K. Prajapati; S. R. Banerjee; S. Mukhopadhyay; D. Pandit; S. Pal; J. K. Meena; P. Mukhopadhyay; A. Chawdhury

    2013-11-08T23:59:59.000Z

    The excited states in the odd-$A$ $^{197}$Tl nucleus have been studied by populating them using the $^{197}$Au($\\alpha$, 4$n$)$^{197}$Tl reaction at the beam energy of 48 MeV. The $\\gamma-\\gamma$ coincidence data were taken using a combination of clover, LEPS and single crystal HPGe detectors. Precise spin and parity assignments of the excited states have been done through the polarization and the DCO measurements. A new band structure has been identified and the evidence for a possible intruder $\\pi i_{13/2}$ state has been found for the first time. Possible configurations of the observed bands have been discussed. The total Routhian surface calculations have been performed to study the shape of $^{197}$Tl for different configurations.

  14. CTu2J.4.pdf CLEO Technical Digest OSA 2012 Selective-Area Growth of Ge and Ge/SiGe Quantum Wells

    E-Print Network [OSTI]

    Miller, David A. B.

    CTu2J.4.pdf CLEO Technical Digest © OSA 2012 Selective-Area Growth of Ge and Ge/SiGe Quantum Wells process for growing high-quality bulk Ge and Ge/SiGe quantum wells in selected areas of 3 µm thick silicon. Introduction and motivation Ge and especially Ge/SiGe quantum wells exhibit strong electroabsorption (Franz

  15. GE Wins Manufacturing Leadership Award |GE Global Research

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    secured software platform that delivers data and visualizations to all major artificial lift functions at GE Oil & Gas. Several analytic modules were built to extract meaningful...

  16. GE Partners on Microgrid Project | GE Global Research

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    and Academia Partner on Microgrid Project GE Awarded a 1.2M Department of Energy Grant to Design Technology to Keep Electricity Flowing after Catastrophic Weather Events...

  17. GE, Aavid Commercialize Dual Cool Jets Technology | GE Global...

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    market. GE's broad array of industrial businesses requires highly advanced and reliable electronics that are increasingly driving the need for advanced cooling solutions to...

  18. GE, University of Washington Disease Detection | GE Global Research

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    excited about this team's unique ability to combine new designs for paper-based microfluidics with new nucleic amplification methods and GE's novel paper chemistries to help...

  19. The GE Store

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our InstagramStructureProposedPAGESafetyTed5,AuditThe FiveBiofuelsGE Store for

  20. Ionic conductivity and dielectric relaxation in {gamma}-irradiated TlGaTe{sub 2} crystals

    SciTech Connect (OSTI)

    Sardarli, R. M., E-mail: sardarli@yahoo.com; Samedov, O. A.; Abdullayev, A. P. [National Academy of Sciences of Azerbaijan, Institute of Radiation Problems (Azerbaijan); Huseynov, E. K. [National Academy of Sciences of Azerbaijan, Institute of Physics (Azerbaijan); Salmanov, F. T.; Alieva, N. A.; Agaeva, R. Sh. [National Academy of Sciences of Azerbaijan, Institute of Radiation Problems (Azerbaijan)

    2013-05-15T23:59:59.000Z

    The switching effect, field and temperature dependences of the permittivity and conductivity of TlGaTe{sub 2} crystals subjected to various {gamma}-irradiation doses are studied. Under rather low electric fields, the phenomenon of threshold switching with an S-shaped current-voltage characteristic containing a portion with negative differential resistance is observed in the crystals. In the region of critical voltages, current and voltage oscillations and imposed modulation are observed. Possible mechanisms of switching, ionic conductivity, disorder, and electrical instability in TlGaTe{sub 2} crystals are discussed.

  1. GE Healthcare Product Guide 2007

    E-Print Network [OSTI]

    Lebendiker, Mario

    GE Healthcare BioProcess Product Guide 2007 #12;How to contact us Europe www.gehealthcare.com/bioprocess or by phone (T), fax (F), and Email Austria T: +43 1 57 606 1613 F: +43 1 57 606 1614 Email: cust.orderde@ge.com Belgium T: 0800 73890 F: 02 416 8206 Email: order.bnl@ge.com Central and East Europe (Austria) T: +43 1

  2. Magnetic Refrigeration | GE Global Research

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

    temperature," said Frank Johnson, a materials scientist and project leader on GE's magnetic refrigeration project. Developed over the past decade, these new magnetocaloric...

  3. Serial and parallel Si, Ge, and SiGe direct-write with scanning...

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

    Serial and parallel Si, Ge, and SiGe direct-write with scanning probes and conducting stamps. Serial and parallel Si, Ge, and SiGe direct-write with scanning probes and conducting...

  4. Performance assessment of CsI(Tl) screens on various substrates for X-ray imaging

    E-Print Network [OSTI]

    Feng, Zhaodong; Zhang, Hongkai; Zhao, Bozhen; Qin, Xiubo; Wei, Cunfeng; Liu, Yu; Wei, Long

    2015-01-01T23:59:59.000Z

    Thallium-doped cesium iodide (CsI(Tl)) screens are widely used in X-ray imaging devices because of the columnar structure of CsI(Tl) layer, but few reports focus on the optical role of the substrate in the screen system. In this paper, four substrates including fused silica (SiO2), silver-film coated SiO2, graphite (C) and fiber optic plate (FOP) are used to fabricate CsI(Tl) screens by thermal evaporation. Their imaging performance is evaluated by relative light output (RLO), modulation transfer function (MTF), normalized noise power spectrum (NNPS) and noise equivalent quanta (NEQ). The results reveal that although CsI(Tl) film on graphite plate yields images with the lowest light output, it presents relatively higher spatial resolution and better signal-to-noise characteristics. However, films on SiO2 plate obtain low MTF but high NNPS curves, whether or not coated with silver film. Furthermore, scintillation screens on FOP have bright images with low NNPS and high NEQ, but have the lowest MTF. By controll...

  5. Current Activities at the ACRELab Renewable Energy Systems Test T.L. Pryor1

    E-Print Network [OSTI]

    of the Australian CRC for Renewable Energy (ACRE) on the Murdoch University campus in Perth, Western Australia is a testing laboratory for Renewable Energy (RE) Systems based at the ACRE headquarters in Perth, AustraliaCurrent Activities at the ACRELab Renewable Energy Systems Test Facility T.L. Pryor1 , E.S. Spooner

  6. Field Tests of a NaI(Tl)-Based Vehicle Portal Monitor at Border Crossings

    SciTech Connect (OSTI)

    Stromswold, David C.; Darkoch, Justin; Ely, James H.; Hansen, Randy R.; Kouzes, Richard T.; Milbrath, Brian D.; Runkle, Robert C.; Sliger, William A.; Smart, John E.; Stephens, Daniel L.; Todd, Lindsay C.; Woodring, Mitchell L.

    2004-10-01T23:59:59.000Z

    Radiation portal monitors are commonly used at international border crossings to detect illicit transport of radioactive material. Most monitors use plastic scintillators to detect gamma rays, but next-generation monitors may contain NaI(Tl). In order to directly compare the performance of the two types of detectors, a prototype NaI(Tl) monitor was tested at two international border crossings adjacent to a comparable plastic scintillator monitor. The NaI(Tl) monitor housed four large detectors, each 10.2 cm x 10.2 cm x 41 cm. The empirical data set from the two field tests contains approximately 3800 passages with known cargo loads for each vehicle For a small subset of the vehicles, high purity germanium detector spectra were also collected. During the survey period several vehicles containing commercial products with naturally occurring radioactive material (NORM) passed through the monitor. Typical NORM cargo included pottery, large granite slabs, rock-based floor tiles, construction stone blocks, abrasive material, and fertilizer. Non-NORM sources encountered during the field tests included a large source of 60Co (200,000 GBq) and a shipment of uranium oxide, both items being legally transported. The information obtained during the tests provides a good empirical data set to compare the effectiveness of NaI(Tl) and plastic-scintillator portal monitors. The capability to be sensitive to illicit materials, but not alarm on NORM, is a key figure of merit for portal monitors. (PIET-43741-TM-210)

  7. CHEM 114 GE 124 MATH 110 COMM 102 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120

    E-Print Network [OSTI]

    Saskatchewan, University of

    2006-07 CHEM 114 GE 124 MATH 110 COMM 102 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120 GEOL 245 MATH 223 CE 328 CE 212 CE 225 CE 295GE 213# MATH 224 GEOL 224 GEOE 218 GEOL 258 Hum/SocSci Jr. GEOE 315 GEOE 475 Grp C Elec.# GE 348#CE 318 CE 319 ENG 11X# GEOL 463 or Grp B Elec.# GEOL 226 GE 300# CE 316

  8. CHEM 114 GE 124 MATH 110 COMM 102 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120

    E-Print Network [OSTI]

    Saskatchewan, University of

    2005-2006 CHEM 114 GE 124 MATH 110 COMM 102 CHEM 115# GE 125 MATH 124 PHYS 155 GE 120 GEOL 245 MATH 223 CE 328 CE 212 CE 225 CE 295GE 213# MATH 224 GEOL 224 GEOE 218 GEOL 258 BusSci/HSS# GEOE 315 GEOE 475 Grp C Elec.# GE 348#CE 318 CE 319 ENG 11X# GEOL 463 or Grp B Elec.# GEOL 226 GE 300# CE 316 Grp

  9. Low-voltage broad-band electroabsorption from thin Ge/SiGe

    E-Print Network [OSTI]

    Miller, David A. B.

    Low-voltage broad-band electroabsorption from thin Ge/SiGe quantum wells epitaxially grown than 5 dB over the entire telecommunication S- and C-bands with only 1V drive using a new Ge/SiGe QW epitaxy design approach; further, this is demonstrated with the thinnest Ge/SiGe epitaxy to date, using

  10. Strained Si, SiGe, and Ge on-insulator: review of wafer bonding fabrication techniques

    E-Print Network [OSTI]

    Strained Si, SiGe, and Ge on-insulator: review of wafer bonding fabrication techniques Gianni was arranged by Prof. C.K. Maiti Abstract Techniques for fabricating strained Si, SiGe, and Ge on is presented, with a detailed discussion of wafer bonding approaches for strained Si, SiGe, and Ge on

  11. GE, Berkeley Energy Storage for Electric Vehicles | GE Global...

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

    Just Add Water: GE, Berkeley Lab Explore Possible Key to Energy Storage for Electric Vehicles Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new...

  12. Cold Spray and GE Technology | GE Global Research

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

    difference of the work done at GE Global Research is the development of cold spray for additive manufacturing, where we adapt this novel coating process to build 3D shapes....

  13. GE Researcher Explores Science Behind Movie Chappie | GE Global...

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

    When Will We Have Robot Best Friends? A GE Researcher Explores the Science Behind Movie Magic Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new...

  14. Joining GE Global Research Thermal Systems | GE Global Research

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

    Alps. With more than 16 years working as an aerospace engineer in the development of gas turbine jet engines, I had GE on my radar screen right from the beginning when I was...

  15. Uniaxially stressed Ge:Ga and Ge:Be

    SciTech Connect (OSTI)

    Dubon, O.D. Jr.

    1992-12-01T23:59:59.000Z

    The application of a large uniaxial stress to p-type Ge single crystals changes the character of both the valence band and the energy levels associated with the acceptors. Changes include the splitting of the fourfold degeneracy of the valence band top and the reduction of the ionization energy of shallow acceptors. In order to study the effect of uniaxial stress on transport properties of photoexcited holes, a variable temperature photo-Hall effect system was built in which stressed Ge:Ga and Ge:Be could be characterized. Results indicate that stress increases the lifetime and Hall mobility of photoexcited holes. These observations may help further the understanding of fundamental physical processes that affect the performance of stressed Ge photoconductors including the capture of holes by shallow acceptors.

  16. The performance of thin NaI(Tl) scintillator plate for dark matter search

    E-Print Network [OSTI]

    K. Fushimi; H. Kawasuso; E. Aihara; R. Hayami; M. Toi; K. Yasuda; S. Nakayama; N. Koori; M. Nomachi; K. Ichihara; R. Hazama; S. Yoshida; S. Umehara; K. Imagawa; H. Ito

    2006-04-15T23:59:59.000Z

    A thin (0.05cm) and wide area (5cmX5cm) NaI(Tl) scintillator was developed. The performance of the thin NaI(Tl) plate, energy resolution, single photoelectron energy and position sensitivity were tested. An excellent energy resolution of 20% (FWHM) at 60keV was obtained. The single photoelectron energy was calculated to be approximately 0.42 0.02keV. Position information in the 5cmx5cm area of the detector was also obtained by analyzing the ratio of the number of photons collected at opposite ends of the detector. The position resolution was obtained to be 1cm (FWHM) in the 5cmx5cm area.

  17. {alpha} decay and recoil decay tagging studies of {sup 183}Tl

    SciTech Connect (OSTI)

    Raddon, P.M.; Jenkins, D.G.; O'Leary, C.D.; Simons, A.J.; Wadsworth, R. [Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom); Andreyev, A.N.; Page, R.D. [Oliver Lodge Laboratory, Department of Physics, University of Liverpool, Liverpool, L69 7ZE (United Kingdom); Carpenter, M.P. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Kondev, F.G. [Technology Development Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Enqvist, T.; Greenlees, P.T.; Jones, P.M.; Julin, R.; Juutinen, S.; Kettunen, H.; Leino, M.; Leppaenen, A.-P.; Nieminen, P.; Pakarinen, J.; Rahkila, P. [Department of Physics, University of Jyvaeskylae, FIN-40351, Jyvaeskylae (Finland)] [and others

    2004-12-01T23:59:59.000Z

    High-spin states in the nucleus {sup 183}Tl have been studied using the recoil decay tagging and recoil tagging techniques. The data have enabled new structures to be identified which are believed to be based on prolate f{sub 7/2}, h{sub 9/2}, and oblate h{sub 9/2} configurations. In addition, the prolate i{sub 3/2} structure has also been extended. The systematics of the newly identified structures will be discussed. The {alpha} decay of {sup 183}Tl has also been investigated. Examination of both delayed and prompt {gamma} rays in coincidence with the prominent 6333-keV {alpha} decay, together with an investigation of the effects of the summing of L electrons, allow assignment of transitions and the construction of tentative low-spin decay schemes for {sup 179}Au and {sup 175}Ir.

  18. Recommended GE Curriculum for the BSEE Majors

    E-Print Network [OSTI]

    Ravikumar, B.

    Recommended GE Curriculum for the BSEE Majors Area Subjects Suggested GE Courses Courses Actual units GE Units A. Communication and Critical Thinking (9) A.2. Fund. of Communication ENGL 101 4 4 A.3, Theatre, Dance and Music and Film Select from the GE C.1 list in the SSU Catalog 3 3 C.2. Literature

  19. Formation of thin film Tl-based high-Tc? superconducting oxides from amorphous alloy precursors

    E-Print Network [OSTI]

    Williams, John Charles

    1991-01-01T23:59:59.000Z

    and satisfying. John Charles Williams TABLE OF CONTENTS ABSTRACT. ACKNOWLEDGMENTS. TABLE OF CONTENTS. LIST OF TABLES. LIST OF FIGURES. I. INTRODUCTION. 1v v vu1 A. Properties of Perovskites and Copper-Oxide Superconductors. . . . . . . . . 2 1.... Fundamental Properties. 2. Perovskite Crystal Structure. 3. Perovskite Crystal Structure Modifications 4, Structure of Thallate Superconductors . . B. Thallium-based Thin Film Superconductors. . . . 1. Tl-based Thin Film Production Methods. . . . 2...

  20. Mass and charge identification of fragments detected with the Chimera Silicon-CsI(Tl) telescopes

    E-Print Network [OSTI]

    N. Le Neindre; for REVERSE collaboration

    2001-12-19T23:59:59.000Z

    Mass and charge identification of charged products detected with Silicon-CsI(Tl) telescopes of the Chimera apparatus is presented. An identification function, based on the Bethe-Bloch formula, is used to fit empirical correlation between Delta E and E ADC readings, in order to determine, event by event, the atomic and mass numbers of the detected charged reaction products prior to energy calibration.

  1. Background studies for NaI(Tl) detectors in the ANAIS dark matter project

    SciTech Connect (OSTI)

    Amaré, J.; Borjabad, S.; Cebrián, S.; Cuesta, C.; Fortuño, D.; García, E.; Ginestra, C.; Gómez, H.; Martínez, M.; Oliván, M. A.; Ortigoza, Y.; Solórzano, A. Ortiz de; Pobes, C.; Puimedón, J.; Sarsa, M. L.; Villar, J. A.; Villar, P. [Laboratorio de Física Nuclear y Astropartículas, Universidad de Zaragoza, Calle Pedro Cerbuna 12, 50009 Zaragoza, Spain and Laboratorio Subterráneo de Canfranc, Paseo de los Ayerbe s/n, 22880 Canfranc Estación, Huesca (Spain)] [Laboratorio de Física Nuclear y Astropartículas, Universidad de Zaragoza, Calle Pedro Cerbuna 12, 50009 Zaragoza, Spain and Laboratorio Subterráneo de Canfranc, Paseo de los Ayerbe s/n, 22880 Canfranc Estación, Huesca (Spain)

    2013-08-08T23:59:59.000Z

    Several large NaI(Tl) detectors, produced by different companies, have been operated in the Canfranc Underground Laboratory (LSC) in the frame of the ANAIS (Annual modulation with NaI Scintillators) project devoted to the direct detection of dark matter. A complete background model has been developed for a 9.6 kg detector (referred as ANAIS-0 prototype) after a long data taking at LSC. Activities from the natural chains of {sup 238}U and {sup 232}Th, and {sup 40}K in the NaI(Tl) crystal were evaluated applying different methods: discrimination of alpha particles vs beta/gamma background by Pulse Shape Analysis for quantifying the content of the natural chains and coincidence techniques for {sup 40}K. Radioactive contaminations in the detector and shielding components were also determined by HPGe spectrometry. Monte Carlo simulations using Geant4 package were carried out to evaluate their contribution. At high energies, most of the measured background is nicely reproduced; at low energy some non-explained components are still present, although some plausible background sources have been analyzed. The {sup 40}K content of the NaI(Tl) crystal has been confirmed to be the dominant contributor to the measured background with this detector. In addition, preliminary results of the background characterization, presently underway at the LSC, of two recently produced NaI(Tl) detectors, with 12.5 kg mass each, will be presented: cosmogenic induced activity has been clearly observed and is being quantified, and {sup 40}K activity at a level ten times lower than in ANAIS-0 has been determined.

  2. High-pressure structural and elastic properties of Tl{sub 2}O{sub 3}

    SciTech Connect (OSTI)

    Gomis, O., E-mail: osgohi@fis.upv.es; Vilaplana, R. [Centro de Tecnologías Físicas, MALTA Consolider Team, Universitat Politècnica de València, 46022 València (Spain); Santamaría-Pérez, D. [Departamento de Física Aplicada-ICMUV, MALTA Consolider Team, Universidad de Valencia, Edificio de Investigación, C/Dr. Moliner 50, 46100 Burjassot (Spain); Earth Sciences Department, University College London, Gower Street, WC1E 6BT London (United Kingdom); Ruiz-Fuertes, J. [Departamento de Física Aplicada-ICMUV, MALTA Consolider Team, Universidad de Valencia, Edificio de Investigación, C/Dr. Moliner 50, 46100 Burjassot (Spain); Geowissenschaften, Goethe-Universität, Altenhöferallee 1, 60438 Frankfurt am Main (Germany); Sans, J. A.; Manjón, F. J.; Mollar, M. [Instituto de Diseño para la Fabricación y Producción Automatizada, MALTA Consolider Team, Universitat Politècnica de València, 46022 València (Spain); and others

    2014-10-07T23:59:59.000Z

    The structural properties of Thallium (III) oxide (Tl{sub 2}O{sub 3}) have been studied both experimentally and theoretically under compression at room temperature. X-ray powder diffraction measurements up to 37.7?GPa have been complemented with ab initio total-energy calculations. The equation of state of Tl{sub 2}O{sub 3} has been determined and compared to related compounds. It has been found experimentally that Tl{sub 2}O{sub 3} remains in its initial cubic bixbyite-type structure up to 22.0?GPa. At this pressure, the onset of amorphization is observed, being the sample fully amorphous at 25.2?GPa. The sample retains the amorphous state after pressure release. To understand the pressure-induced amorphization process, we have studied theoretically the possible high-pressure phases of Tl{sub 2}O{sub 3}. Although a phase transition is theoretically predicted at 5.8?GPa to the orthorhombic Rh{sub 2}O{sub 3}-II-type structure and at 24.2?GPa to the orthorhombic ?-Gd{sub 2}S{sub 3}-type structure, neither of these phases were observed experimentally, probably due to the hindrance of the pressure-driven phase transitions at room temperature. The theoretical study of the elastic behavior of the cubic bixbyite-type structure at high-pressure shows that amorphization above 22?GPa at room temperature might be caused by the mechanical instability of the cubic bixbyite-type structure which is theoretically predicted above 23.5?GPa.

  3. GeSi intermixing in Ge quantum dots on Si,,001... and Si,,111... F. Boscherinia)

    E-Print Network [OSTI]

    Ge­Si intermixing in Ge quantum dots on Si,,001... and Si,,111... F. Boscherinia) Laboratori December 1999 Exploiting Ge K-edge x-ray absorption spectroscopy we provide direct evidence of Si­Ge intermixing in self-organized strained and unstrained Ge quantum dots on Si, and provide a quantitative

  4. Nonlithographic epitaxial SnxGe1x dense nanowire arrays grown on Ge,,001...

    E-Print Network [OSTI]

    Atwater, Harry

    Nonlithographic epitaxial SnxGe1Àx dense nanowire arrays grown on Ge,,001... Regina Ragan-thick SnxGe1 x /Ge(001) epitaxial films with 0 x 0.085 by molecular-beam epitaxy. These films evolve during growth into a dense array of SnxGe1 x nanowires oriented along 001 , as confirmed by composition contrast

  5. Valley splitting theory of SiGe/Si/SiGe quantum wells Mark Friesen,1,

    E-Print Network [OSTI]

    Coppersmith, Susan N.

    Valley splitting theory of SiGe/Si/SiGe quantum wells Mark Friesen,1, * Sucismita Chutia,1 Charles an effective mass theory for SiGe/Si/SiGe quantum wells, with an emphasis on calculating the valley splitting interface, with characteristic energy splittings of order 0.1­1 meV for the case of SiGe/Si/SiGe quantum

  6. High-pressure single-crystal X-ray diffraction of Tl{sub 2}SeO{sub 4}

    SciTech Connect (OSTI)

    Grzechnik, Andrzej [Departamento de Fisica de la Materia Condensada, Universidad del Pais Vasco, E-48080 Bilbao (Spain)], E-mail: andrzej.grzechnik@ehu.es; Breczewski, Tomasz; Friese, Karen [Departamento de Fisica de la Materia Condensada, Universidad del Pais Vasco, E-48080 Bilbao (Spain)

    2008-11-15T23:59:59.000Z

    The effect of pressure on the crystal structure of thallium selenate (Tl{sub 2}SeO{sub 4}) (Pmcn, Z=4), containing the Tl{sup +} cations with electron lone pairs, has been studied with single-crystal X-ray diffraction in a diamond anvil cell up to 3.64 GPa at room temperature. No phase transition has been observed. The compressibility data are fitted by a Murnaghan equation of state with the zero-pressure bulk modulus B{sub 0}=29(1) GPa and the unit-cell volume at ambient pressure V{sub 0}=529.6(8) A{sup 3} (B'=4.00). Tl{sub 2}SeO{sub 4} is the least compressible in the c direction, while the pressure-induced changes of the a and b lattice parameters are quite similar. These observations can be explained by different pressure effects on the nine- and 11-fold coordination polyhedra around the two non-equivalent Tl atoms. The SeO{sub 4}{sup 2-} tetrahedra are not rigid units and become more distorted. Their contribution to the compressibility is small. The effect of pressure on the isotypical oxide materials A{sub 2}TO{sub 4} with the {beta}-K{sub 2}SO{sub 4} structure is discussed. It appears that the presence of electron lone pairs on the Tl{sup +} cation does not seem to influence the compressibility of Tl{sub 2}SeO{sub 4}. - Graphical abstract: Pressure dependence of normalized lattice parameters and unit-cell volumes in Tl{sub 2}SeO{sub 4} (Pmcn, Z=4). The solid line is the Murnaghan equation of state.

  7. Rolling up SiGe on insulator

    SciTech Connect (OSTI)

    Cavallo, F.; Songmuang, R.; Ulrich, C.; Schmidt, O. G. [Max-Planck-Institut fuer Festkoerperforschung, Heisenbergstrasse 1, D-70569 Stuttgart (Germany)

    2007-05-07T23:59:59.000Z

    SiGe on insulator films of 10-50 nm thickness are fabricated by Ge condensation applying different oxidation times. The layers are released from the substrate by selectively etching the insulator film. Due to the varying Ge composition, the layers bend downward toward the substrate surface and roll up into microtubes. Depending on the Ge condensation, the strain distribution in the SiGe layers varies and allows a scaling of the tube diameters between 1 and 4 {mu}m. Assuming pseudomorphic SiGe layers, the tube diameters are smaller than expected from continuum mechanical theory. This suggests the occurrence of additional strain in the oxidized films.

  8. Neutron Scattering Study on spin dynamics in superconducting (TlRb)2Fe4Se5

    SciTech Connect (OSTI)

    Chi, Songxue [ORNL; Ye, Feng [ORNL; Bao, Wei [Renmin University of China; Fang, Dr. Minghu [Zhejiang University; Wang, H.D. [Zhejiang University; Dong, C.H. [Zhejiang University; Savici, Andrei T [ORNL; Granroth, Garrett E [ORNL; Stone, Matthew B [ORNL; Fishman, Randy Scott [ORNL

    2013-01-01T23:59:59.000Z

    Spin dynamics in superconducting (Tl,Rb)2Fe4Se5 was investigated using the inelastic neutron scattering technique. Spin wave branches that span an energy range from 6.5 to 209 meV are success- fully described by a Heisenberg model whose dominant interactions include only the in-plane nearest (J1 and J0 1) and next nearest neighbor (J2 and J0 2) exchange terms within and between the tetramer spin blocks, respectively. These exchange constants, experimentally determined in this work, would crucially constrain the diverse theoretical viewpoints on magnetism and superconductivity in the Fe-based materials.

  9. Acoustoelectric effects in very high-mobility p-SiGe/Ge/SiGe heterostructure

    SciTech Connect (OSTI)

    Drichko, I. L.; Diakonov, A. M.; Lebedeva, E. V.; Smirnov, I. Yu. [A. F. Ioffe Physico-Technical Institute of Russian Academy of Sciences, 194021 St. Petersburg (Russian Federation); Mironov, O. A. [Warwick SEMINANO R and D Centre, University of Warwick Science Park, Coventry CV4 7EZ (United Kingdom); Kummer, M.; Kaenel, H. von [Laboratorium fuer Festkoerperphysik ETH Zuerich, CH-8093 Zuerich (Switzerland); EpiSpeed SA, Technoparkstrasse 1, CH-8005 Zuerich (Switzerland)

    2009-11-01T23:59:59.000Z

    Measurement results of the acoustoelectric effects [surface acoustic waves (SAW) attenuation and velocity] in a high-mobility p-SiGe/Ge/SiGe structure are presented. The structure was low-energy plasma-enhanced chemical vapor deposition grown with a two-dimensional (2D) channel buried in the strained Ge layer. The measurements were performed as a function of temperature (1.5-4.2 K) and magnetic field (up to 8.4 T) at different SAW intensities at frequencies 28 and 87 MHz. Shubnikov-de Haas-like oscillations of both SAW attenuation and the velocity change have been observed. Hole density and mobility, effective mass, quantum and transport relaxation times, as well as the Dingle temperature were measured with a method free of electric contacts. The effect of heating of the 2D hole gas by the electric field of the SAW was investigated. Energy relaxation time tau{sub e}psilon and the deformation potential constant determined.

  10. PROBABILITY OF CORRECT SELECTION OF GAMMA VERSUS GE OR WEIBULL VERSUS GE BASED ON

    E-Print Network [OSTI]

    Kundu, Debasis

    PROBABILITY OF CORRECT SELECTION OF GAMMA VERSUS GE OR WEIBULL VERSUS GE BASED ON LIKELIHOOD RATIO proposes the use of likelihood ratio statistic in choosing between gamma and GE models or between Weibull and GE models. Probability of correct selec- tions are obtained using Monte Carlo simulations for various

  11. Scintillation efficiency measurement of Na recoils in NaI(Tl) below the DAMA/LIBRA energy threshold

    E-Print Network [OSTI]

    Xu, Jingke; Calaprice, Frank; Westerdale, Shawn; Froborg, Francis; Suerfu, Burkhant; Alexander, Thomas; Aprahamian, Ani; Back, Henning O; Casarella, Clark; Fang, Xiao; Gupta, Yogesh K; Ianni, Aldo; Lamere, Edward; Lippincott, W Hugh; Liu, Qian; Lyons, Stephanie; Siegl, Kevin; Smith, Mallory; Tan, Wanpeng; Kolk, Bryant Vande

    2015-01-01T23:59:59.000Z

    The dark matter interpretation of the DAMA modulation signal depends on the NaI(Tl) scintillation efficiency of nuclear recoils. Previous measurements for Na recoils have large discrepancies, especially in the DAMA/LIBRA modulation energy region. We report a quenching effect measurement of Na recoils in NaI(Tl) from 3keV$_{\\text{nr}}$ to 52keV$_{\\text{nr}}$, covering the whole DAMA/LIBRA energy region for light WIMP interpretations. By using a low-energy, pulsed neutron beam, a double time-of-flight technique, and pulse-shape discrimination methods, we obtained the most accurate measurement of this kind for NaI(Tl) to date. The results differ significantly from the DAMA reported values at low energies, but fall between the other previous measurements. We present the implications of the new quenching results for the dark matter interpretation of the DAMA modulation signal.

  12. Superconducting Tl/sub 2/Ba/sub 2/CuO/sub 6/: the orthorhombic form

    SciTech Connect (OSTI)

    Parise, J.B.; Gopalakrishnan, J.; Subramanian, M.A.; Sleight, A.W.

    1988-10-01T23:59:59.000Z

    The structure of an orthorhombic variant of Tl/sub 2/Ba/sub 2/CuO/sub 6/ (Z = 4), with a superconducting onset at 90K, has been studied using neutron powder diffractometry at 12 K (a = 5.4834(3), b = 5.4586(3), c = 23.198(1) /Angstrom/), 60 K (a = 5.4834(3), b = 5.4585(3), c = 23.199(1) /Angstrom/), and 293 K (a = 5.4967(3), b = 5.4651(3), c = 23.246(1) /Angstrom/). The distortion from I4/mmm symmetry, reported in single-crystal X-ray investigations, to Abma is manifested in the Tl-O layer. At the temperatures studied, the coordination of Tl to oxygen is (2 + 1 + 2) square pyramidal rather than octahedral. At lower temperatures, distortion decreases but does not disappear. Despite the orthorhombic symmetry the CuO/sub 2/-layers remain flat.

  13. Understanding and engineering of NiGe/Ge junction formed by phosphorus ion implantation after germanidation

    SciTech Connect (OSTI)

    Oka, Hiroshi, E-mail: oka@asf.mls.eng.osaka-u.ac.jp; Minoura, Yuya; Hosoi, Takuji; Shimura, Takayoshi; Watanabe, Heiji [Department of Material and Life Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2014-08-11T23:59:59.000Z

    Modulation of the effective electron Schottky barrier height (eSBH) of NiGe/Ge contacts induced by phosphorus ion implantation after germanide formation was investigated by considering local inhomogeneity in the eSBH. Systematic studies of NiGe/Ge contact devices having various germanide thicknesses and ion implantation areas indicated the threshold dopant concentration at the NiGe/Ge interface required for eSBH modulation and negligible dopant diffusion even at NiGe/Ge interface during drive-in annealing, leading to variation in the eSBH between the bottom and sidewall portions of the NiGe regions. Consequently, this method makes it possible to design source/drain contacts with low-resistivity Ohmic and ideal rectifying characteristics for future Ge-based transistors.

  14. Measurements of NaI:Tl Electron Response using SLYNCI: Comparison of Different Samples

    SciTech Connect (OSTI)

    Hull, G; Choong, W; Moses, W W; Bizarri, G; Valentine, J D; Payne, S A; Cherepy, N; Reutter, B W

    2007-11-12T23:59:59.000Z

    This paper measures the sample to sample variation in the light yield non-proportionality of NaI:Tl, and so explores whether this is an invariant characteristic of the material or whether it is dependent on the chemical and physical properties of tested sample. In this work we report on the electron response of nine crystals of NaI(Tl), differing in shape, volume, age, manufacturer and quality. The non-proportionality has been measured at the SLYNCI facility in the energy range between 3.5 to 460 keV. The Scintillation Light Yield Non-proportionality Characterization Instrument (SLYNCI) is a next generation Compton Coincidence device, explicitly designed to study the 'non-proportionality' of the electron response in scintillators and the contribution of this effect to the intrinsic energy resolution. We also discuss the gamma response, x-ray excited emission spectra and decay times for the nine crystals, in order to provide a complete characterization of their physical properties and determine whether the mechanism of scintillation varies between samples.

  15. Measurements of NaI(Tl) electron response: comparison of different samples

    SciTech Connect (OSTI)

    Hull, Giulia; Choong, Woon-Seng; Moses, William W.; Bizarri, Gregory; Valentine, John D.; Payne, Stephen A.; Cherepy, Nerine J.; Reutter, Bryan W.

    2008-12-10T23:59:59.000Z

    This paper measures the sample to sample variation in the light yield proportionality of NaI(Tl), and so explores whether this is an invariant characteristic of the material or whether it depends on the chemical and physical properties of the tested samples. We report on the electron response of nine crystals of NaI(Tl), differing in shape, volume, age, manufacturer and quality. The proportionality has been measured at the SLYNCI facility in the energy range between 3.5 to 460 keV. We observe that while samples produced by the same manufacturer at approximately the same time have virtually identical electron response curves, there are significant sample to sample variations among crystals produced by different manufacturers or at different times. In an effort to correlate changes in the electron response with details of the scintillation mechanism, we characterized other scintillation properties, including the gamma response and the x-ray excited emission spectra and decay times, for the nine crystals. While sample to sample differences in these crystals were observed, we have been unable to identify the underlying fundamental mechanisms that are responsible for these differences.

  16. Protein degradation in a TX-TL cell-free expression system using ClpXP protease Zachary Z. Sun1

    E-Print Network [OSTI]

    Murray, Richard M.

    ! 1! Protein degradation in a TX-TL cell-free expression system using ClpXP protease AUTHORS that play an important role for in vivo circuit dynamics ­ namely protein degradation and protein dilution-TL with ClpXP, an AAA+ protease pair that selectively degrades tagged proteins [11], to provide finely

  17. SiGe-On-Insulator (SGOI) Technology and MOSFET Fabrication

    E-Print Network [OSTI]

    SiGe-On-Insulator (SGOI) Technology and MOSFET Fabrication Zhiyuan Cheng, E. A. Fitzgerald, and D with less defects in SiGe film, but the SiGe film uniformity is inferior. "Smart-cut" approach has better control on the SiGe film thickness and uniformity, and is applicable to wider Ge content range of the SiGe

  18. About GE Global Research Center | GE Global Research

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItem NotEnergy,ARMForms About Become agovEducationWelcome toAboutAbout GE Global Research

  19. Heat Transfer in GE Jet Engines | GE Global Research

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cn SunnybankD.jpgHanfordDepartment ofHeat Transfer in GE Jet Engines Click to

  20. Hall-Coefficient for Oriented Tl2ba2cacu2o8+delta Thin-Films

    E-Print Network [OSTI]

    WANG, PS; WILLIAMS, JC; RATHNAYAKA, KDD; HENNINGS, BD; Naugle, Donald G.; KAISER, AB.

    1993-01-01T23:59:59.000Z

    Measurements of the Hall coefficient and resistivity for highly oriented Tl2Ba2CaCu2O8+delta thin films are reported. The temperature dependence of cotTHETA(H), where THETA(H) is the normal-state Hall angle, for a single-phase (2:2:1:2) film sample...

  1. Photoconductivity of Si/Ge multilayer structures with Ge quantum dots pseudomorphic to the Si matrix

    SciTech Connect (OSTI)

    Talochkin, A. B., E-mail: tal@thermo.isp.nsc.ru; Chistokhin, I. B. [Russian Academy of Sciences, Rzhanov Institute of Semiconductor Physics, Siberian Branch (Russian Federation)

    2011-07-15T23:59:59.000Z

    Longitudinal photoconductivity spectra of Si/Ge multilayer structures with Ge quantum dots grown pseudomorphically to the Si matrix are studied. Lines of optical transitions between hole levels of quantum dots and Si electronic states are observed. This allowed us to construct a detailed energy-level diagram of electron-hole levels of the structure. It is shown that hole levels of pseudomorphic Ge quantum dots are well described by the simplest 'quantum box' model using actual sizes of Ge islands. The possibility of controlling the position of the long-wavelength photosensitivity edge by varying the growth parameters of Si/Ge structures with Ge quantum dots is determined.

  2. Advanced Analytics | GE Global Research

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWP TWP Related LinksATHENAAdministrative80-AA (01-2015)GE

  3. Thermal Imaging Technologies | GE Global Research

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

    Enables Advanced Thermal Imaging An error occurred. Unable to execute Javascript. Bryan Whalen in the Electronics Cooling Lab at GE Global Research recorded this thermo...

  4. Limited-area growth of Ge and SiGe on Si

    E-Print Network [OSTI]

    Kim, Meekyung, Ph. D. Massachusetts Institute of Technology

    2011-01-01T23:59:59.000Z

    The goal of this thesis is to develop and understand processing conditions that improve the surface morphology and reduce the dislocation density in limited-area heteroepitaxy of Ge and SiGe on Si (100) substrates. Low ...

  5. SiGe/sSi quantum dot electron spin decoherence dependence on $^{73}$Ge

    E-Print Network [OSTI]

    Witzel, Wayne M; Carroll, Malcolm S

    2011-01-01T23:59:59.000Z

    We theoretically study the nuclear spin induced decoherence of a quantum dot in Si that is confined at a SiGe interface. We calculate decoherence time dependence on $^{73}$Ge in the barrier layer to evaluate the importance of Ge as well as Si enrichment for long decoherence times. We use atomistic tight-binding modeling for an accurate account of the electron wavefunction which is particularly important for determining the contact hyperfine interactions with the Ge nuclear spins. We find decoherence times due to Ge spins at natural concentrations to be milliseconds. This suggests SiGe/sSi quantum dot devices employing enriched Si will require enriched Ge as well in order to benefit from long coherence times. We provide a comparison of $T_2$ times for various fractions of nonzero spin isotopes of Si and Ge.

  6. SiGe/Si quantum dot electron spin decoherence dependence on $^{73}$Ge

    E-Print Network [OSTI]

    Wayne M. Witzel; Rajib Rahman; Malcolm S. Carroll

    2012-05-14T23:59:59.000Z

    We theoretically study the nuclear spin induced decoherence of a quantum dot in Si that is confined at a SiGe interface. We calculate decoherence time dependence on $^{73}$Ge in the barrier layer to evaluate the importance of Ge as well as Si enrichment for long decoherence times. We use atomistic tight-binding modeling for an accurate account of the electron wavefunction which is particularly important for determining the contact hyperfine interactions with the Ge nuclear spins. We find decoherence times due to Ge spins at natural concentrations to be milliseconds. This suggests SiGe/Si quantum dot devices employing enriched Si will require enriched Ge as well in order to benefit from long coherence times. We provide a comparison of $T_2$ times for various fractions of nonzero spin isotopes of Si and Ge.

  7. MOSFET Channel Engineering using Strained Si, SiGe, and Ge Channels

    E-Print Network [OSTI]

    Fitzgerald, Eugene A.

    Biaxial tensile strained Si grown on SiGe virtual substrates will be incorporated into future generations of CMOS technology due to the lack of performance increase with scaling. Compressively strained Ge-rich alloys with ...

  8. Enhanced Hole Mobility in High Ge Content Asymmetrically Strained-SiGe p-MOSFETs

    E-Print Network [OSTI]

    Chléirigh, C. Ni

    The hole mobility characteristics of ?110? /(100)-oriented asymmetrically strained-SiGe p-MOSFETs are studied.

  9. Comparison of LaBr3:Ce and NaI(Tl) Scintillators for Radio-Isotope Identification Devices

    SciTech Connect (OSTI)

    Milbrath, Brian D.; Choate, Bethany J.; Fast, Jim E.; Hensley, Walter K.; Kouzes, Richard T.; Schweppe, John E.

    2006-07-31T23:59:59.000Z

    Lanthanum halide (LaBr3:Ce) scintillators offer significantly better resolution (<3 percent at 662 kilo-electron volt [keV]) relative to sodium iodide (NaI(Tl)) and have recently become commercially available in sizes large enough for the hand-held radio-isotope identification device (RIID) market. There are drawbacks to lanthanum halide detectors, however. These include internal radioactivity that contributes to spectral counts and a low-energy response that can cause detector resolution to be lower than that of NaI(Tl) below 100 keV. To study the potential of this new material for RIIDs, we performed a series of measurements comparing a 1.5?1.5 inch LaBr?3:Ce detector with an Exploranium GR 135 RIID, which contains a 1.5-2.2 inch NaI(Tl) detector. Measurements were taken for short time frames, as typifies RIID usage. Measurements included examples of naturally occurring radioactive material (NORM), typically found in cargo, and special nuclear materials. Some measurements were noncontact, involving short distances or cargo shielding scenarios. To facilitate direct comparison, spectra from the different detectors were analyzed with the same isotope identification software (ORTEC ScintiVision TM). In general, the LaBr3:Ce detector was able to find more peaks and find them faster than the NaI(Tl) detector. To the same level of significance, the LaBr3:Ce detector was usually two to three times faster. The notable exception was for 40K containing NORM where interfering internal contamination in the LaBr3:Ce detector exist. NaI(Tl) consistently outperformed LaBr3:Ce for this important isotope. LaBr3:Ce currently costs much more than NaI(Tl), though this cost-difference is expected to diminish (but not completely) with time. As is true of all detectors, LaBr3:Ce will need to be gain-stabilized for RIID applications. This could possibly be done using the internal contaminants themselves. It is the experience of the authors that peak finding software in RIIDs needs to be improved, regardless of the detector material.

  10. Modeling of GE Appliances: Final Presentation

    SciTech Connect (OSTI)

    Fuller, Jason C.; Vyakaranam, Bharat; Leistritz, Sean M.; Parker, Graham B.

    2013-01-31T23:59:59.000Z

    This report is the final in a series of three reports funded by U.S. Department of Energy Office of Electricity Delivery and Energy Reliability (DOE-OE) in collaboration with GE Appliances’ through a Cooperative Research and Development Agreement (CRADA) to describe the potential of GE Appliances’ DR-enabled appliances to provide benefits to the utility grid.

  11. Relaxed SiGe Layers with High Ge Content by Compliant Substrates , R.L. Peterson1

    E-Print Network [OSTI]

    Relaxed SiGe Layers with High Ge Content by Compliant Substrates H. Yin1 , R.L. Peterson1 , K, high Ge content SiGe layers have been realized using stress balance on a compliant under compression. Upon equilibrium after an annealing, stress balance was formed between the SiGe films

  12. Effects of Interface Disorder on Valley Splitting in SiGe/Si/SiGe Quantum Wells

    E-Print Network [OSTI]

    Zhengping Jiang; Neerav Kharche; Timothy Boykin; Gerhard Klimeck

    2012-03-06T23:59:59.000Z

    A sharp potential barrier at the Si/SiGe interface introduces valley splitting (VS), which lifts the 2-fold valley degeneracy in strained SiGe/Si/SiGe quantum wells (QWs). This work examines in detail the effects of Si/SiGe interface disorder on the VS in an atomistic tight binding approach based on statistical sampling. VS is analyzed as a function of electric field, QW thickness, and simulation domain size. Strong electric fields push the electron wavefunctions into the SiGe buffer and introduce significant VS fluctuations from device to device. A Gedankenexperiment with ordered alloys sheds light on the importance of different bonding configurations on VS. We conclude that a single SiGe band offset and effective mass cannot comprehend the complex Si/SiGe interface interactions that dominate VS.

  13. Effects of Interface Disorder on Valley Splitting in SiGe/Si/SiGe Quantum Wells

    E-Print Network [OSTI]

    Jiang, Zhengping; Boykin, Timothy; Klimeck, Gerhard

    2011-01-01T23:59:59.000Z

    A sharp potential barrier at the Si/SiGe interface introduces valley splitting (VS), which lifts the 2-fold valley degeneracy in strained SiGe/Si/SiGe quantum wells (QWs). This work examines in detail the effects of Si/SiGe interface disorder on the VS in an atomistic tight binding approach based on statistical sampling. VS is analyzed as a function of electric field, QW thickness, and simulation domain size. Strong electric fields push the electron wavefunctions into the SiGe buffer and introduce significant VS fluctuations from device to device. A Gedankenexperiment with ordered alloys sheds light on the importance of different bonding configurations on VS. We conclude that a single SiGe band offset and effective mass cannot comprehend the complex Si/SiGe interface interactions that dominate VS.

  14. Monolithic Ge-on-Si lasers for integrated photonics

    E-Print Network [OSTI]

    Liu, Jifeng

    We report room temperature Ge-on-Si lasers with direct gap emission at 1590-1610 nm. Modeling of Ge/Si double heterojunction structures, which is supported by experimental results of Ge/Si LEDs, indicates the feasibility ...

  15. Ge-on-Si laser for silicon photonics

    E-Print Network [OSTI]

    Camacho-Aguilera, Rodolfo Ernesto

    2013-01-01T23:59:59.000Z

    Ge-on-Si devices are explored for photonic integration. Importance of Ge in photonics has grown and through techniques developed in our group we demonstrated low density of dislocations (Ge ...

  16. Is there a risk from not using GE animals?

    E-Print Network [OSTI]

    Murray, James D.; Maga, Elizabeth A.

    2010-01-01T23:59:59.000Z

    Is there a risk from not using GE animals? James D. Murray •rst genetically engi- neered (GE) plants and animals forthe debate often focuses on GE as a technique that is used

  17. Germanium: From Its Discovery to SiGe Devices

    E-Print Network [OSTI]

    Haller, E.E.

    2006-01-01T23:59:59.000Z

    From Its Discovery to SiGe Devices E.E. Haller Department ofrapidly rising interest in SiGe alloys, we are just startingstrained and unstrained SiGe multilayer structures [58]. 9.

  18. Structure of the Si(001)-(2x2)-Tl phase at 0.5 monolayer coverage

    SciTech Connect (OSTI)

    Visikovskiy, Anton [Department of Molecular and Material Sciences, Kyushu University, 6-1 Kasugakouen, Kasuga, Fukuoka 816-8580 (Japan); Institute of Automation and Control Processes, 5 Radio Street, Vladivostok 690041 (Russian Federation); Mizuno, Seigi; Tochihara, Hiroshi [Department of Molecular and Material Sciences, Kyushu University, 6-1 Kasugakouen, Kasuga, Fukuoka 816-8580 (Japan)

    2005-06-15T23:59:59.000Z

    A (2x2) structure formed by thallium (Tl) atoms on the Si(001) surface at 0.5 monolayer coverage at room temperature has been studied by a tensor low-energy electron-diffraction (LEED) analysis. Twenty-four structural models were tested. The valley-bridge para dimer model, being produced also by other trivalent metals, was found to be the most optimal. It is concluded, therefore, that the so-called 'inert pair effect' of Tl atoms does not play a significant role in the case of this (2x2) structure. The structural parameters obtained by first-principles total-energy calculations are in good agreement with those obtained by the LEED analysis.

  19. Scaling of SiGe Heterojunction Bipolar Transistors

    E-Print Network [OSTI]

    Rieh, Jae-Sung

    Scaling of SiGe Heterojunction Bipolar Transistors JAE-SUNG RIEH, SENIOR MEMBER, IEEE, DAVID-century. This paper inves- tigates the impacts of scaling on SiGe heterojunction bipolar tran- sistors (HBTs), which), epitaxial-base Si BJTs (Epi Si BJT), SiGe HBTs (SiGe HBT), and SiGe HBTs with carbon-doped base (SiGeC HBT

  20. SPECTROMTRE 03B1 A SCINTILLATION AVEC I Cs(Tl) Par J. FLEURY, P. PERRIN, M. BOGE et J. LAUGIER,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    480. SPECTROMÈTRE 03B1 A SCINTILLATION AVEC I Cs(Tl) Par J. FLEURY, P. PERRIN, M. BOGE et J 03B1 de 9 MeV. Abstract. 2014 In spectrometry with CsI(Tl) crystals the following characteristicsV with NaI). The best resolution in spectrometry 03B1 is 2.5 % with 9 MeV 03B1-particles. LE .IOURNAL DE

  1. Understanding of interface structures and reaction mechanisms induced by Ge or GeO diffusion in Al{sub 2}O{sub 3}/Ge structure

    SciTech Connect (OSTI)

    Shibayama, Shigehisa [Department of Crystalline Materials Science, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan) [Department of Crystalline Materials Science, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); JSPS, 5-3-1 Kojimachi, Chiyoda-ku, Tokyo 102-0083 (Japan); Kato, Kimihiko; Sakashita, Mitsuo; Takeuchi, Wakana; Taoka, Noriyuki; Nakatsuka, Osamu; Zaima, Shigeaki [Department of Crystalline Materials Science, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan)] [Department of Crystalline Materials Science, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan)

    2013-08-19T23:59:59.000Z

    The reaction mechanisms at Al{sub 2}O{sub 3}/Ge interfaces with thermal oxidation through the Al{sub 2}O{sub 3} layer have been investigated. X-ray photoelectron spectroscopy reveals that an Al{sub 6}Ge{sub 2}O{sub 13} layer is formed near the interface, and a GeO{sub 2} layer is formed on the Al{sub 2}O{sub 3} surface, suggesting Ge or GeO diffusion from the Ge surface. It is also clarified that the Al{sub 6}Ge{sub 2}O{sub 13} layer is formed by the different mechanism with a small activation energy of 0.2 eV, compared with the GeO{sub 2} formation limited by oxygen diffusion. Formation of Al-O-Ge bonds due to the AlGeO formation could lead appropriate interface structures with high interface qualities.

  2. Enhancement of thermal stability and water resistance in yttrium-doped GeO{sub 2}/Ge gate stack

    SciTech Connect (OSTI)

    Lu, Cimang, E-mail: cimang@adam.t.u-tokyo.ac.jp; Hyun Lee, Choong; Zhang, Wenfeng; Nishimura, Tomonori; Nagashio, Kosuke; Toriumi, Akira [Department of Materials Engineering, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-8656 (Japan); JST, CREST, 7-3-1 Hongo, Tokyo 113-8656 (Japan)

    2014-03-03T23:59:59.000Z

    We have systematically investigated the material and electrical properties of yttrium-doped GeO{sub 2} (Y-GeO{sub 2}) on Germanium (Ge). A significant improvement of both thermal stability and water resistance were demonstrated by Y-GeO{sub 2}/Ge stack, compared to that of pure GeO{sub 2}/Ge stack. The excellent electrical properties of Y-GeO{sub 2}/Ge stacks with low D{sub it} were presented as well as enhancement of dielectric constant in Y-GeO{sub 2} layer, which is beneficial for further equivalent oxide thickness scaling of Ge gate stack. The improvement of thermal stability and water resistance are discussed both in terms of the Gibbs free energy lowering and network modification of Y-GeO{sub 2}.

  3. Engineer Receives UMass "Salute To Service" Award | GE Global...

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

    November 22, 2013 - GE Global Research, the technology development arm of the General Electric Company (NYSE: GE), is proud to announce that Dr. Marshall Jones, a world renowned...

  4. Crowdsourcing Wins Manufacturing Leadership 100 | GE Global Research

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

    NY, May 22, 2013 - GE Global Research, the technology development arm of the General Electric Co. (NYSE: GE) today announced that it has won a prestigious Manufacturing Leadership...

  5. Testimonials - Partnerships in Fuel Cells - GE Global Research...

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

    Fuel Cells - GE Global Research Testimonials - Partnerships in Fuel Cells - GE Global Research Addthis An error occurred. Unable to execute Javascript. Text Version The words...

  6. Butterfly-Inspired Thermal Imaging | GE Global Research

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

    primusenginefeaturedimage3 GE Innovation and Manufacturing in Europe 2-4-13-v-3d-printing-medical-devices Additive Manufacturing Demonstration at GE Global Research ...

  7. Comparison of PVT And NaI(Tl) Scintillators for Vehicle Portal Monitor Applications

    SciTech Connect (OSTI)

    Siciliano, Edward R.; Ely, James H.; Kouzes, Richard T.; Milbrath, Brian D.; Schweppe, John E.; Stromswold, David C.

    2005-09-21T23:59:59.000Z

    The demand for radiation portal monitor (RPM) systems has increased, and their capabilities are being further scrutinized as they are being applied to the task of detecting nuclear weapons, special nuclear material, and radiation dispersal device materials that could appear at borders. The requirements and constraints on RPM systems deployed at high-volume land border crossings are significantly different from those at weapons facilities and steel recycling plants, where RPMs have been historically employed. In this new homeland security application, RPM systems must rapidly detect localized sources of radiation with a very high detection probability and low false-alarm rate, while screening “100%” of the traffic without impeding the flow of commerce. In light of this new DHS application, this report re-examines the capabilities of two popular gamma-ray-detector materials to meet the needs of RPM systems. This is accomplished by using experimental data and computer simulations together with practical deployment experience to assess the capabilities of currently available polyvinyl-toluene and NaI(Tl) gamma detectors. (PIET-43741-TM-057)

  8. ME 227 CE 212 MATH 223 GE 210 CMPT 116 ABE 211CHE 210 GE 213# MATH 224

    E-Print Network [OSTI]

    Saskatchewan, University of

    GE 120 ME 227 CE 212 MATH 223 GE 210 CMPT 116 ABE 211CHE 210 GE 213# MATH 224 ABE 295 ABE 212Elective* Elective* AB E 311 ABE 313 ABE 312 GE 348#ABE 323 co-requisite ABE 327 HSS#@ HSS#@ ABE 324 GE 300# ABE 395 4TH YEAR ABE Elec* ABE Elec* ABE Elec*ABE 422 GE 449# Ag Elec* T.E.* T.E.* ABE Elec* Ag Elec

  9. Thermal conductivity of sputtered amorphous Ge films

    SciTech Connect (OSTI)

    Zhan, Tianzhuo; Xu, Yibin; Goto, Masahiro; Tanaka, Yoshihisa; Kato, Ryozo; Sasaki, Michiko; Kagawa, Yutaka [National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-0047 (Japan)] [National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-0047 (Japan)

    2014-02-15T23:59:59.000Z

    We measured the thermal conductivity of amorphous Ge films prepared by magnetron sputtering. The thermal conductivity was significantly higher than the value predicted by the minimum thermal conductivity model and increased with deposition temperature. We found that variations in sound velocity and Ge film density were not the main factors in the high thermal conductivity. Fast Fourier transform patterns of transmission electron micrographs revealed that short-range order in the Ge films was responsible for their high thermal conductivity. The results provide experimental evidences to understand the underlying nature of the variation of phonon mean free path in amorphous solids.

  10. Energy band alignment of atomic layer deposited HfO{sub 2} oxide film on epitaxial (100)Ge, (110)Ge, and (111)Ge layers

    SciTech Connect (OSTI)

    Hudait, Mantu K.; Zhu Yan [Advanced Devices and Sustainable Energy Laboratory (ADSEL), Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States)

    2013-03-21T23:59:59.000Z

    Crystallographically oriented epitaxial Ge layers were grown on (100), (110), and (111)A GaAs substrates by in situ growth process using two separate molecular beam epitaxy chambers. The band alignment properties of atomic layer hafnium oxide (HfO{sub 2}) film deposited on crystallographically oriented epitaxial Ge were investigated using x-ray photoelectron spectroscopy (XPS). Valence band offset, {Delta}E{sub v} values of HfO{sub 2} relative to (100)Ge, (110)Ge, and (111)Ge orientations were 2.8 eV, 2.28 eV, and 2.5 eV, respectively. Using XPS data, variation in valence band offset, {Delta}E{sub V}(100)Ge>{Delta}E{sub V}(111)Ge>{Delta}E{sub V}(110)Ge, was obtained related to Ge orientation. Also, the conduction band offset, {Delta}E{sub c} relation, {Delta}E{sub c}(110)Ge>{Delta}E{sub c}(111)Ge>{Delta}E{sub c}(100)Ge related to Ge orientations was obtained using the measured bandgap of HfO{sub 2} on each orientation and with the Ge bandgap of 0.67 eV. These band offset parameters for carrier confinement would offer an important guidance to design Ge-based p- and n-channel metal-oxide field-effect transistor for low-power application.

  11. GE Appliances: Order (2010-CE-2113)

    Broader source: Energy.gov [DOE]

    DOE issued an Order after entering into a Compromise Agreement with General Electric Appliances after finding GE Appliances had failed to certify that certain models of dehumidifiers comply with the applicable energy conservation standards.

  12. GE's Christine Furstoss Named to NACIE

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

    companies like GE will need workers with new and advanced skills in areas like 3D printing and virtual design. It's all about growing a new generation of workforce skills,...

  13. GE Unveils High-Tech Superhero GENIUS MAN | GE Global Research

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

    education Committed to inspiring the next generation of scientists and engineers Infused with an array of superpowers inspired by GE technologies Super Vision, ability to...

  14. Be a part of something bigger than yourself GE Healthcare

    E-Print Network [OSTI]

    Rimon, Elon

    Be a part of something bigger than yourself GE Healthcare Position: Mechanical Engineer as a contractor · Working at GE site at Tirat-Carmel. · Start: immediately · Duration 6-10 months, with optional elongation. ElgemsMoked@ge.com-CV www.gehealthcare.com We are GE Healthcare, a $17 billion division

  15. UC IRVINE GENERAL EDUCATION (GE) REQUIREMENT AND APPROVED GE COURSES, 201213 Includes course titles and Schedule of Classes designations

    E-Print Network [OSTI]

    Loudon, Catherine

    UC IRVINE GENERAL EDUCATION (GE) REQUIREMENT AND APPROVED GE COURSES, 2012­13 Includes course titles and Schedule of Classes designations GENERAL EDUCATION (GE) REQUIREMENT UCI is committed undergraduates complete a set of general education (GE) requirements. General education courses introduce

  16. 2009-10 Princeton Global Scholar Ge Zhaoguang. Professor Ge is the founding director of the National Institute for Advanced

    E-Print Network [OSTI]

    2009-10 Princeton Global Scholar Ge Zhaoguang. Professor Ge is the founding director, and emendation of all sorts of newly discovered texts (mostly found at archaeological sites). Professor Ge University, Professor Ge taught at Tsinghua University for a number of years. He is known for many important

  17. Measurement of the direct energy gap of coherently strained SnxGe1x Ge,,001... heterostructures

    E-Print Network [OSTI]

    Atwater, Harry

    Measurement of the direct energy gap of coherently strained SnxGe1Àx ÕGe,,001... heterostructures The direct energy gap has been measured for coherently strained SnxGe1 x alloys on Ge 001 substrates with 0 for coherently strained SnxGe1 x alloys indicates a large alloy contribution and a small strain contribution

  18. GE Advising & Registration Students FT Faculty PT Faculty Admin Unit 4 Other Staff Students have access to quality GE advising

    E-Print Network [OSTI]

    de Lijser, Peter

    GE Advising & Registration Students FT Faculty PT Faculty Admin Unit 4 Other Staff Students have access to quality GE advising 9% 13% 11% 13% 10% 8% Faculty can easily advise students on GE requirements 10% 18% 9% 24% 33% 11% Staff academic advisors can easily advise students on GE requirements 8% 11

  19. High-germanium-content SiGe islands formed on compliant oxide by SiGe Haizhou Yina)

    E-Print Network [OSTI]

    High-germanium-content SiGe islands formed on compliant oxide by SiGe oxidation Haizhou Yina and the nonuniformity of the enhanced germanium content during the SiGe oxidation were improved by depositing a silicon was relaxed by lateral expansion of the SiGe islands, showing that dislocations were not required

  20. Relaxation and recombination processes in Ge/SiGe multiple quantum wells

    SciTech Connect (OSTI)

    Gatti, E., E-mail: gatti@mater.unimib.it; Giorgioni, A., E-mail: gatti@mater.unimib.it; Grilli, E., E-mail: gatti@mater.unimib.it; Guzzi, M., E-mail: gatti@mater.unimib.it [L-NESS and Università di Milano-Bicocca, Dip. di Scienza dei Materiali, via Cozzi 53, 20125 Milano (Italy); Chrastina, D.; Isella, G. [L-NESS and Politecnico di Milano, Dip. di Fisica, via Anzani 42, 22100 Como (Italy); Chernikov, A.; Kolata, K.; Bornwasser, V.; Köster, N. S.; Woscholski, R.; Chatterjee, S. [Faculty of Physics and Materials Sciences Center, Philipps-Universität, Renthof 5, 35032 Marburg (Germany)

    2013-12-04T23:59:59.000Z

    The carrier dynamics that occurs in Ge/SiGe QWs when electrons are excited to confined states at ? is studied by means of optical spectroscopy at different lattice temperatures. The typical times for the different relaxation and recombination processes are given and discussed.

  1. Deviations from ideal nucleation-limited relaxation in high-Ge content compositionally graded SiGe/Si*

    E-Print Network [OSTI]

    Deviations from ideal nucleation-limited relaxation in high-Ge content compositionally graded SiGe the sudden rise in threading dislocation density in Ge-rich relaxed graded SiGe layers grown at higher growth systems, including relaxed graded SiGe on Si substrates i.e., x Si1-xGex /Si ,1,2 InGaP on GaP substrates

  2. Thermoelectric properties of M{sub 2}Mo{sub 6}Se{sub 6} (M =Tl,In)

    SciTech Connect (OSTI)

    Verebelyi, D.T.; Payne, J.E.; Tessema, G.X.; Mengistu, E.

    1997-07-01T23:59:59.000Z

    The authors have measured the thermal conductivity of Tl{sub 2}Mo{sub 6}Se{sub 6}, a quasi-one dimensional conductor which belongs to the family of M{sub 2}Mo{sub 6}X{sub 6} linear chain compounds. Using these results and the measurements of the Seebeck coefficient and the electrical conductivity the authors estimate the dimensionless figure of merit to be of the order of 0.08. This result suggest that this compound and other related compounds are good potential TE.

  3. Band gap engineering of In{sub 2}O{sub 3} by alloying with Tl{sub 2}O{sub 3}

    SciTech Connect (OSTI)

    Scanlon, David O., E-mail: d.scanlon@ucl.ac.uk [Kathleen Lonsdale Materials Chemistry, Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ (United Kingdom); Diamond Light Source Ltd., Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE (United Kingdom); Regoutz, Anna; Egdell, Russell G. [Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QR (United Kingdom)] [Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QR (United Kingdom); Morgan, David J. [Cardiff Catalysis Institute (CCI), School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT (United Kingdom)] [Cardiff Catalysis Institute (CCI), School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT (United Kingdom); Watson, Graeme W. [School of Chemistry and CRANN, Trinity College Dublin, Dublin 2 (Ireland)] [School of Chemistry and CRANN, Trinity College Dublin, Dublin 2 (Ireland)

    2013-12-23T23:59:59.000Z

    Efficient modulation of the bandgap of In{sub 2}O{sub 3} will open up a route to improved electronic properties. We demonstrate using ab initio calculations that Tl incorporation into In{sub 2}O{sub 3} reduces the band gap and confirm that narrowing of the gap is observed by X-ray photoemission spectroscopy on ceramic surfaces. Incorporation of Tl does not break the symmetry of the allowed optical transitions, meaning that the doped thin films should retain optical transparency in the visible region, in combination with a lowering of the conduction band effective mass. We propose that Tl-doping may be an efficient way to increase the dopability and carrier mobility of In{sub 2}O{sub 3}.

  4. Ge/SiGe quantum wells on Si(111): Growth, structural, and optical properties

    SciTech Connect (OSTI)

    Gatti, E., E-mail: eleonora.gatti@mater.unimib.it; Pezzoli, F.; Grilli, E. [L-NESS and Dipartimento di Scienza dei Materiali, Università di Milano Bicocca, via Cozzi 55, I-20125 Milano (Italy); Isa, F.; Chrastina, D.; Isella, G. [L-NESS and Dipartimento di Fisica, Politecnico di Milano, Polo di Como, via Anzani 42, I - 22100 Como (Italy); Müller Gubler, E. [Electron Microscopy Center of ETH Zürich (EMEZ), August-Piccard-Hof 1, CH-8093 Zürich (Switzerland)

    2014-07-28T23:59:59.000Z

    The epitaxial growth of Ge/Si{sub 0.15}Ge{sub 0.85} multiple quantum wells (MQWs) on Si(111) substrates is demonstrated. A 3??m thick reverse, double-step virtual substrate with a final composition of Si{sub 0.10}Ge{sub 0.90} has been employed. High resolution XRD, TEM, AFM and defect etching analysis has been used for the study of the structural properties of the buffer and of the QWs. The QW stack is characterized by a threading dislocation density of about 3?×?10{sup 7?}cm{sup ?2} and an interdiffusion layer at the well/barrier interface of 2.1?nm. The quantum confined energy levels of this system have been calculated using the k·p and effective mass approximation methods. The Ge/Si{sub 0.15}Ge{sub 0.85} MQWs have been characterized through absorption and photoluminescence measurements. The optical spectra have been compared with those of Ge/Si{sub 0.15}Ge{sub 0.85} QWs grown on Si(001) through a thick graded virtual substrate.

  5. Optical Link on Silicon Employing Ge/SiGe Quantum Well Structures Onur Fidaner, Ali K. Okyay, Jonathan E. Roth, Rebecca K. Scheavitz, Yu-Hsuan Kuo*

    E-Print Network [OSTI]

    Miller, David A. B.

    Optical Link on Silicon Employing Ge/SiGe Quantum Well Structures Onur Fidaner, Ali K. Okyay University, Taipei, Taiwan Abstract: We demonstrate an optical link on silicon employing Ge/SiGe quantum well of the quantum-confined Stark effect (QCSE) on silicon using Ge/SiGe quantum wells opened up the possibility

  6. The thermoelectric properties of Ge/SiGe modulation doped superlattices A. Samarelli, L. Ferre Llin, S. Cecchi, J. Frigerio, T. Etzelstorfer et al.

    E-Print Network [OSTI]

    Hague, Jim

    The thermoelectric properties of Ge/SiGe modulation doped superlattices A. Samarelli, L. Ferre Llin thermoelectric properties of Ge/SiGe modulation doped superlattices A. Samarelli,1 L. Ferre Llin,1 S. Cecchi,2 J in the thermoelectric figure of merit, ZT, and power factor at room temperature over bulk Ge, Si1ÀyGey, and Si/Ge

  7. 23 6 12 8:00 III-V/Ge CMOS

    E-Print Network [OSTI]

    Katsumoto, Shingo

    23 6 12 8:00 - 1 - 1. : III-V/Ge CMOS ~ 200%~ 2. : III-V (Ge) III-V/Ge CMOS (Si) 200% III-V/Ge CMOS 200% III-V/Ge CMOS () () () () III-V III-V/Ge CMOS (1) III-V Ge III-V/Ge CMOS (2) III-V-OI MOSFET (3) III-V/Ge CMOS "2011 Symposia on VLSI

  8. Measurement of the neutron-capture cross section of ??Ge and ??Ge below 15 MeV and its relevance to 0??? decay searches of ??Ge

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

    Bhike, Megha; Fallin, B.; Tornow, W.

    2015-02-01T23:59:59.000Z

    The neutron radiative-capture cross section of ??Ge was measured between 0.4 and 14.8 MeV using the activation technique. Germanium samples with the isotopic abundance of ~86% ??Ge and ~14% ??Ge used in the 0??? searches by the GERDA and Majorana Collaborations were irradiated with monoenergetic neutrons produced at eleven energies via the ³H(p,n)³He, ²H(d,n)³He and ³H(d,n)?He reactions. Previously, data existed only at thermal energies and at 14 MeV. As a by-product, capture cross-section data were also obtained for ??Ge at neutron energies below 8 MeV. Indium and gold foils were irradiated simultaneously for neutron fluence determination. High-resolution ?-ray spectroscopy wasmore »used to determine the ?-ray activity of the daughter nuclei of interest. For the ??Ge total capture cross section the present data are in good agreement with the TENDL-2013 model calculations and the ENDF/B-VII.1 evaluations, while for the ??Ge(n,?)??Ge reaction, the present data are about a factor of two larger than predicted. It was found that the ??Ge(n,?)??Ge yield in the High-Purity Germanium (HPGe) detectors used by the GERDA and Majorana Collaborations is only about a factor of two smaller than the ??Ge(n,?)??Ge yield due to the larger cross section of the former reaction.« less

  9. GE Lighting Solutions: Order (2013-SE-4901)

    Broader source: Energy.gov [DOE]

    DOE ordered General Electric Lighting Solutions, LLC to pay a $5,360 civil penalty after finding GE Lighting Solutions had manufactured and distributed in commerce in the U.S. 30 units of basic model DR4-RTFB-23B and 177 units (of which 85 units remain in inventory) of basic model DR4-RTFB-77A-002, noncompliant traffic signal modules.

  10. Viscosity Measurement G.E. Leblanc

    E-Print Network [OSTI]

    Kostic, Milivoje M.

    30 Viscosity Measurement G.E. Leblanc McMaster University R.A. Secco The University of Western Ontario 30.1 Shear Viscosity ............................................................. 30-l Newtonian and Non-Newtonian Fluids l Dimensions and Units of Viscosity l Viscometer Types l Capillary M. Kostic

  11. GE Teams with NY College to Pilot SOFC Technology |GE Global...

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

    Hudson Valley Community College to Pilot GE Solid Oxide Fuel Cell Technology Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new window) Click to...

  12. GE partners with 'Girls Who Code' for summer program | GE Global...

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

    share on LinkedIn (Opens in new window) Click to share on Tumblr (Opens in new window) GE Partners with 'Girls Who Code' for Summer Immersion Program to Help Close the Gender Gap...

  13. GE, NASA Work to Relaunch Supersonic Air Travel | GE Global Research

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

    share on LinkedIn (Opens in new window) Click to share on Tumblr (Opens in new window) GE Supporting NASA's efforts to Relaunch Commercial Supersonic Air Travel Awarded 2- year...

  14. Metastability and relaxation in tensile SiGe on Ge(001) virtual substrates

    SciTech Connect (OSTI)

    Frigerio, Jacopo; Lodari, Mario; Chrastina, Daniel, E-mail: daniel.chrastina@polimi.it; Mondiali, Valeria; Isella, Giovanni [L-NESS, Dipartimento di Fisica, Politecnico di Milano, Polo di Como, via Anzani 42, 22100 Como (Italy); Bollani, Monica [IFN-CNR, L-NESS, via Anzani 42, 22100 Como (Italy)

    2014-09-21T23:59:59.000Z

    We systematically study the heteroepitaxy of SiGe alloys on Ge virtual substrates in order to understand strain relaxation processes and maximize the tensile strain in the SiGe layer. The degree of relaxation is measured by high-resolution x-ray diffraction, and surface morphology is characterized by atomic force microscopy. The results are analyzed in terms of a numerical model, which considers dislocation nucleation, multiplication, thermally activated glide, and strain-dependent blocking. Relaxation is found to be sensitive to growth rate and substrate temperature as well as epilayer misfit and thickness, and growth parameters are found which allow a SiGe film with over 4?GPa of tensile stress to be obtained.

  15. The Majorana Ge-76 double-beta decay project

    SciTech Connect (OSTI)

    Avignone, Frank Titus [ORNL

    2010-01-01T23:59:59.000Z

    The MAJORANA Project is a research and development activity set up to establish the feasibility and cost of a doublebetadecay experiment comprising a one-ton array of Ge detectors fabricated from germanium enriched to about 86% in Ge-76.

  16. GE launches 'STEM empowers OK' initiative in Oklahoma City |...

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

    ok GE Foundation donates 400,000 to enhance STEM education initiatives across Oklahoma STEM Empowers OK to sponsor week-long, GE Summer Science Academy at OSSM for Oklahoma...

  17. Passionate Technologists Wanted at ASME Turbo Expo|GE Global...

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

    Meet & Greet GE Researchers at ASME Turbo 2014 Thomas Ripplinger 2014.06.10 Do you love gas turbine research as much as I do? Then I want to meet you next week Since joining GE...

  18. Driving Sensing Technology in Oil & Gas | GE Global Research

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

    a bit more about Bill's work. Bill joined GE Global Research in 2010. For the past four years his emphasis has been on developing advanced photonics technologies for multiple GE...

  19. Tailoring the spin polarization in Ge/SiGe multiple quantum wells

    SciTech Connect (OSTI)

    Giorgioni, Anna; Pezzoli, Fabio; Gatti, Eleonora; Grilli, Emanuele; Guzzi, Mario [LNESS-Dipartimento di Scienza dei Materiali, Università degli Studi di Milano-Bicocca, I-20125 Milano (Italy); Bottegoni, Federico; Cecchi, Stefano; Ciccacci, Franco; Isella, Giovanni [LNESS-Dipartimento di Fisica, Politecnico di Milano, I-20133 Milano (Italy); Trivedi, Dhara; Song, Yang [Department of Physics and Astronomy, University of Rochester, Rochester (United States); Li, Pengki [Department of Electrical and Computer Engineering, University of Rochester, Rochester (United States); Dery, Hanan [Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627 and Department of Electrical and Computer Engineering, University of Rochester, Rochester (United States)

    2013-12-04T23:59:59.000Z

    We performed spin-resolved photoluminescence measurements on Ge/SiGe multiple quantum wells with different well thickness and using different exciting power densities. The polarization of the direct emission strongly depends on the relative weight of electrons photoexcited from the light and the heavy hole subbands. The study of the polarization as a function of the exciting power highlights the role of the carrier-carrier interactions in determining spin depolarization.

  20. Strain and stability of ultrathin Ge layers in Si/Ge/Si axial heterojunction nanowires

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

    Ross, Frances M.; Stach, Eric A.; Wen, Cheng -Yen; Reuter, Mark C.; Su, Dong

    2015-03-11T23:59:59.000Z

    The abrupt heterointerfaces in the Si/Ge materials system presents useful possibilities for electronic device engineering because the band structure can be affected by strain induced by the lattice mismatch. In planar layers, heterointerfaces with abrupt composition changes are difficult to realize without introducing misfit dislocations. However, in catalytically grown nanowires, abrupt heterointerfaces can be fabricated by appropriate choice of the catalyst. Here we grow nanowires containing Si/Ge and Si/Ge/Si structures respectively with sub-1nm thick Ge "quantum wells" and we measure the interfacial strain fields using geometric phase analysis. Narrow Ge layers show radial strains of several percent, with a correspondingmore »dilation in the axial direction. Si/Ge interfaces show lattice rotation and curvature of the lattice planes. We conclude that high strains can be achieved, compared to what is possible in planar layers. In addition, we study the stability of these heterostructures under heating and electron beam irradiation. The strain and composition gradients are supposed to the cause of the instability for interdiffusion.« less

  1. Thin SiGe virtual substrates for Ge heterostructures integration on silicon

    SciTech Connect (OSTI)

    Cecchi, S., E-mail: stefano.cecchi@mdm.imm.cnr.it; Chrastina, D.; Frigerio, J.; Isella, G. [L-NESS, Dipartimento di Fisica, Politecnico di Milano–Polo Territoriale di Como, Via Anzani 42, I-22100 Como (Italy); Gatti, E.; Guzzi, M. [L-NESS, Dipartimento di Scienza dei Materiali, Università di Milano Bicocca, via Cozzi 53, I-20126 Milano (Italy); Müller Gubler, E. [Electron Microscopy ETH Zurich, ETH Zurich, Auguste-Piccard-Hof 1, CH-8093 Zurich (Switzerland); Paul, D. J. [School of Engineering, University of Glasgow, Rankine Building, Oakfield Avenue, Glasgow G12 8LT (United Kingdom)

    2014-03-07T23:59:59.000Z

    The possibility to reduce the thickness of the SiGe virtual substrate, required for the integration of Ge heterostructures on Si, without heavily affecting the crystal quality is becoming fundamental in several applications. In this work, we present 1??m thick Si{sub 1?x}Ge{sub x} buffers (with x?>?0.7) having different designs which could be suitable for applications requiring a thin virtual substrate. The rationale is to reduce the lattice mismatch at the interface with the Si substrate by introducing composition steps and/or partial grading. The relatively low growth temperature (475?°C) makes this approach appealing for complementary metal-oxide-semiconductor integration. For all the investigated designs, a reduction of the threading dislocation density compared to constant composition Si{sub 1?x}Ge{sub x} layers was observed. The best buffer in terms of defects reduction was used as a virtual substrate for the deposition of a Ge/SiGe multiple quantum well structure. Room temperature optical absorption and photoluminescence analysis performed on nominally identical quantum wells grown on both a thick graded virtual substrate and the selected thin buffer demonstrates a comparable optical quality, confirming the effectiveness of the proposed approach.

  2. Similarity of Stranski-Krastanow growth of Ge/Si and SiGe/Si (001)

    SciTech Connect (OSTI)

    Norris, D. J.; Qiu, Y.; Walther, T. [Department of Electronic and Electrical Engineering, University of Sheffield, Mappin Building, Mappin Street, Sheffield S1 3JD (United Kingdom); Dobbie, A.; Myronov, M. [Department of Physics, University of Warwick, Coventry CV4 7A (United Kingdom)

    2014-01-07T23:59:59.000Z

    This study investigates the onset of islanding (Stranski-Krastanow transition) in strained pure germanium (Ge) and dilute silicon-germanium (SiGe) alloy layers grown by chemical vapour deposition on Si(001) substrates. Integration of compositional profiles is compared to a novel method for quantification of X-ray maps acquired in cross-sectional scanning transmission electron microscopy, together with simulations of surface segregation of Ge. We show that Si{sub 1?x}Ge{sub x} alloys for germanium concentrations x???0.27 grow two-dimensionally and stay flat up to considerable layer thicknesses, while layers with concentrations in the range 0.28?Ge is ±(0.2–0.3) ML. Modelling shows that of the amount of germanium deposited, 0.7 ML segregate towards the free surface so that only ?2.3/x ML are directly incorporated in the layer within a few nanometres, in good agreement with our measurements. For pure Ge (x?=?1), this thickness is smaller than most values quoted in the literature, which we attribute to the high sensitivity of our method to fractional monolayer changes in the effective chemical width of such thin layers.

  3. Monolithic Ge/Si Avalanche Photodiodes Yimin Kanga*

    E-Print Network [OSTI]

    Bowers, John

    Monolithic Ge/Si Avalanche Photodiodes Yimin Kanga* , Mike Morsea , Mario J. Panicciaa , Moshe, Charlottesville, VA 22904, USA Abstract: We demonstrate mesa-type and waveguide-type Ge/Si avalanche photodiodes. Research on the Ge/Si photodiodes, one of the fundamental components needed for building integrated silicon

  4. MOTION OF ELECTRON-HOLE DROPS IN Ge

    E-Print Network [OSTI]

    Westervelt, R.M.

    2011-01-01T23:59:59.000Z

    MOTION OF ELECTRON-HOLE DROPS IN Ge R. M. Westervelt, J. C.MOTION OF ELECTRON-HOLE DROPS IN Ge R. M. Westervelt, J. C.OF ELECTRON-HOLE DROPS IN Ge R M Westervelt, J C Culbertson

  5. Ge.Meyer -MPL-27.11.002 Status Tunerentwicklung

    E-Print Network [OSTI]

    Ge.Meyer -MPL- 27.11.002 Status Tunerentwicklung 1) Geschichte: Alter franz. Tuner weich, hatte Hysterese. Federkonstante: Gerechnet 5,4 µ/kN, gemessen 26,7 µ/kN (Faktor 5), Ge.Meyer gerechnet 14,6 µ Felder. 2) Tuner 0 / H.Kaiser, Ge.Meyer -MPL- Deshalb wurde ein neues Konzept überlegt. Dieses Konzept

  6. Conduction band discontinuity and electron confinement at the Si[subscript x]Ge[subscript 1?x]/Ge interface

    E-Print Network [OSTI]

    Mazzeo, G.

    Germanium rich heterostructures can constitute a valid alternative to Silicon for the confinement of single electron spins. The conduction band discontinuity in SiGe/Ge heterostructures grown on pure germanium substrate ...

  7. Initially awarded for 1 year and renewed for a second year with satisfactory progress The NIHfunded TRANSFORM TL1 Personalized Medicine Training Program

    E-Print Network [OSTI]

    Grishok, Alla

    1 Initially awarded for 1 year and renewed for a second year with satisfactory progress The NIHfunded TRANSFORM TL1 Personalized Medicine Training Program Columbia University INFORMATION Medicine Training Program, which offers structured training and practical exposure to the needed training

  8. Measurement of the Low Energy Nuclear Response in NaI(Tl) Crystals for Use in Dark Matter Direct Detection Experiments

    E-Print Network [OSTI]

    Stiegler, Tyana Michele

    2013-07-30T23:59:59.000Z

    The response of low energy nuclear recoil in NaI(Tl) is investigated in the following experiment. Such detectors have been used recently to search for evidence of dark matter in the form of weakly interacting massive particles (WIMPs). Na...

  9. Submillimeter and microwave residual losses in epitaxial films of Y-Ba-Cu-O and Tl-Ca-Ba-Cu-O

    SciTech Connect (OSTI)

    Miller, D.; Richards, P.L. [Lawrence Berkeley Lab., CA (United States); Garrison, S.M.; Newman, N. [Conductus, Inc., Sunnyvale, CA (United States); Eom, C.B.; Geballe, T.H. [Stanford Univ., CA (United States). Dept. of Applied Physics; Etemad, S.; Inam, A.; Venkatesan, T. [Bell Communications Research, Inc., Red Bank, NJ (United States); Martens, J.S. [Sandia National Labs., Albuquerque, NM (United States); Lee, W.Y. [International Business Machines Corp., San Jose, CA (United States); Bourne, L.C. [Superconductor Technologies, Inc., Santa Barbara, CA (United States)

    1992-03-01T23:59:59.000Z

    We have used a novel bolometric technique and a resonant technique to obtain accurate submillimeter and microwave residual loss data for epitaxial thin films of YBa{sub 2}Cu{sub 3}O{sub 7}, Tl{sub 2}Ca{sub 2}Ba{sub 2}Cu{sub 3}O{sub 10} and Tl{sub 2}CaBa{sub 2}Cu{sub 2}O{sub 8}. For all films we obtain good agreement between the submillimeter and microwave data, with the residual losses in both the Y-Ba-Cu-O and Tl-Ca-Ba-Cu-O films scaling approximately as frequency squared below {approximately} 1 THz. We are able to fit the losses in the Y-Ba-Cu-O films to a weakly coupled grain model for the a-b plane conductivity, in good agreement with results from a Kramers-Kronig analysis of the loss data. We observe strong phonon structure in the Tl-Ca-Ba-Cu-O films for frequencies between 2 and 21 THz, and are unable to fit these losses to the simple weakly coupled grain model. This is in strong contrast to the case for other high {Tc} superconductors such as YBa{sub 2}Cu{sub 3}O{sub 7}, where phonon structure observed in ceramic samples is absent in epitaxial oriented films and crystals because of the electronic screening due to the high conductivity of the a-b planes.

  10. Suppression of activation energy and superconductivity by the addition of Al{sub 2}O{sub 3} nanoparticles in CuTl-1223 matrix

    SciTech Connect (OSTI)

    Jabbar, Abdul; Qasim, Irfan; Mumtaz, M.; Zubair, M.; Nadeem, K. [Materials Research Laboratory, Department of Physics, FBAS, International Islamic University (IIU) Islamabad, Islamabad 44000 (Pakistan); Khurram, A. A. [Experimental Physics Labs, National Centre for Physics, Islamabad (Pakistan)

    2014-05-28T23:59:59.000Z

    Low anisotropic (Cu{sub 0.5}Tl{sub 0.5})Ba{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10??} (CuTl-1223) high T{sub c} superconducting matrix was synthesized by solid-state reaction and Al{sub 2}O{sub 3} nanoparticles were prepared separately by co-precipitation method. Al{sub 2}O{sub 3} nanoparticles were added with different concentrations during the final sintering cycle of CuTl-1223 superconducting matrix to get the required (Al{sub 2}O{sub 3}){sub y}/CuTl-1223, y?=?0.0, 0.5, 0.7, 1.0, and 1.5?wt.?%, composites. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy, energy dispersive X-ray, and dc-resistivity (?) measurements. The activation energy and superconductivity were suppressed with increasing concentration of Al{sub 2}O{sub 3} nanoparticles in (CuTl-1223) matrix. The XRD analysis showed that the addition of Al{sub 2}O{sub 3} nanoparticles did not affect the crystal structure of the parent CuTl-1223 superconducting phase. The suppression of activation energy and superconducting properties is most probably due to weak flux pinning in the samples. The possible reason of weak flux pinning is reduction of weak links and enhanced inter-grain coupling due to the presence of Al{sub 2}O{sub 3} nanoparticles at the grain boundaries. The presence of Al{sub 2}O{sub 3} nanoparticles at the grain boundaries possibly reduced the number of flux pinning centers, which were present in the form of weak links in the pure CuTl-1223 superconducting matrix. The increase in the values of inter-grain coupling (?) deduced from the fluctuation induced conductivity analysis with the increased concentration of Al{sub 2}O{sub 3} nanoparticles is a theoretical evidence of improved inter-grain coupling.

  11. 33rd International Lie`ge Colloquium on Ocean Dynamics Lie`ge, Belgium, May 711, 2001

    E-Print Network [OSTI]

    Leonard, John J.

    Preface 33rd International Lie`ge Colloquium on Ocean Dynamics Lie`ge, Belgium, May 7­11, 2001 The International Lie`ge Colloquium on Ocean Dynamics is organized annually. The topic differs from year to year. Assembling a group of active and eminent scien- tists from various countries and often different disci

  12. Measured difference between 206Pb, 205Tl charge distributions and the proton 3s1/2 wave function

    E-Print Network [OSTI]

    Anders, M R; Talmi, I

    2015-01-01T23:59:59.000Z

    Charge density difference between 206Pb and 205Tl, measured by elastic electron scattering, is very similar to the charge density due to a proton in a 3s1/2 orbit. We look for a potential well whose 3s1/2 wave function yields the measured data. We developed a novel method to obtain the potential directly from the density and its first and second derivatives. Fits to parametrized potentials were also carried out. The 3s1/2 wave functions of the potentials determined here, reproduce fairly well the experimental data within the quoted errors. To detect possible effects of short-range two-body correlations on the 3s1/2 shell model wave function, more accurate measurements are required.

  13. Measured difference between 206Pb, 205Tl charge distributions and the proton 3s1/2 wave function

    E-Print Network [OSTI]

    M. R. Anders; S. Shlomo; I. Talmi

    2015-04-21T23:59:59.000Z

    Charge density difference between 206Pb and 205Tl, measured by elastic electron scattering, is very similar to the charge density due to a proton in a 3s1/2 orbit. We look for a potential well whose 3s1/2 wave function yields the measured data. We developed a novel method to obtain the potential directly from the density and its first and second derivatives. Fits to parametrized potentials were also carried out. The 3s1/2 wave functions of the potentials determined here, reproduce fairly well the experimental data within the quoted errors. To detect possible effects of short-range two-body correlations on the 3s1/2 shell model wave function, more accurate measurements are required.

  14. Properties of excited states in {sup 77}Ge.

    SciTech Connect (OSTI)

    Kay, B. P.; Chiara, C. J.; Schiffer, J. P.; Kondev, F. G.; Zhu, S.; Carpenter, M. P.; Janssens, R. V. F.; Lauritsen, T.; Lister, C. J.; McCutchan, E. A.; Seweryniak, D.; Stefanescu, I.; Univ. of Maryland; Horia-Hulubei National Inst. for Physics and Nuclear Engineering

    2009-07-01T23:59:59.000Z

    The nucleus {sup 77}Ge was studied through the {sup 76}Ge({sup 13}C,{sup 12}C){sup 77}Ge reaction at a sub-Coulomb energy. The angular distributions of rays depopulating excited states in {sup 77}Ge were measured in order to constrain spin and parity assignments. Some of these assignments are of use in connection with neutrinoless double beta decay, where the population of states near the Fermi surface of {sup 76}Ge was recently explored using transfer reactions.

  15. Role of nucleation sites on the formation of nanoporous Ge

    SciTech Connect (OSTI)

    Yates, B. R.; Darby, B. L.; Jones, K. S. [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611-6400 (United States); Elliman, R. G. [Department of Electronic Materials Engineering, Research School of Physical Sciences and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia)

    2012-09-24T23:59:59.000Z

    The role of nucleation sites on the formation of nanoporous Ge was investigated. Three Ge films with different spherical or columnar pore morphologies to act as inherent nucleation sites were sputtered on (001) Ge. Samples were implanted 90 Degree-Sign from incidence at 300 keV with fluences ranging from 3.0 Multiplication-Sign 10{sup 15} to 3.0 Multiplication-Sign 10{sup 16} Ge{sup +}/cm{sup 2}. Electron microscopy investigations revealed varying thresholds for nanoporous Ge formation and exhibited a stark difference in the evolution of the Ge layers based on the microstructure of the initial film. The results suggest that the presence of inherent nucleation sites significantly alters the onset and evolution of nanoporous Ge.

  16. Monolayer Passivation of Ge(100) Surface via Nitridation and Oxidation Joon Sung Leea,b

    E-Print Network [OSTI]

    Kummel, Andrew C.

    Monolayer Passivation of Ge(100) Surface via Nitridation and Oxidation Joon Sung Leea,b , Sarah R passivation of Ge(100) surface via formation of Ge-N and Ge-O surface species was studied using scanning cyclotron resonance (ECR) plasma source formed an ordered Ge-N structure on a Ge(100) surface at 500o C. DFT

  17. Prompt Gamma Rays in {sup 77}Ge after Neutron Capture on {sup 76}Ge

    SciTech Connect (OSTI)

    Meierhofer, Georg; Grabmayr, Peter; Jochum, Josef [Physikalisches Institut, Eberhard Karls Universitaet Tuebingen, Auf der Morgenstelle 14, 72076 Tuebingen (Germany); Canella, Lea [Institut fuer Radiochemie, Technische Universitaet Muenchen, Walther-Meissner-Str. 3, 85748 Garching (Germany); Jolie, Jan; Kudejova, Petra; Warr, Nigel [Institut fuer Kernphysik, Universitaet zu Koeln, Zuelpicher Str. 77, 50937 Cologne (Germany)

    2009-01-28T23:59:59.000Z

    The observation of neutrinoless double beta decay would be proof of the Majorana nature of the neutrino. Half-lives for these decays are very long (for {sup 76}Ge:>10{sup 25} y), so background reduction and rejection is the major task for double beta experiments. The GERDA (GERmanium Detector Array) experiment at the Gran Sasso Laboratory of the INFN (LNGS) searches for neutrinoless double beta decay of {sup 76}Ge. The isotope {sup 76}Ge is an ideal candidate because it can be used as source and detector at the same time. A large remaining contribution to the background arises from the prompt gamma cascade after neutron capture by {sup 76}Ge followed by {beta}{sup -}-decay of {sup 77}Ge. Since the prompt gamma decay scheme is poorly known, measurements with isotopically enriched Germanium samples were carried out at the PGAA facility at the research reactor FRM II (Munich). With the known prompt gamma spectrum it will be possible to improve the overall veto efficiency of the GERDA experiment.

  18. Material properties in SiGe/Ge quantum wells Rebecca K. Schaevitz*, Jonathan E. Roth, Onur Fidaner, and David A. B. Miller

    E-Print Network [OSTI]

    Miller, David A. B.

    Material properties in SiGe/Ge quantum wells Rebecca K. Schaevitz*, Jonathan E. Roth, Onur Fidaner *Corresponding author: rschaevitz@stanford.edu Abstract: Photocurrent measurements in Ge quantum wells parameters for design of high-performance SiGe/Ge quantum well optoelectronics on silicon. Germanium

  19. Ge/SiGe Quantum Confined Stark Effect Modulators on Silicon James S. Harris, Yu-Hsuan Kuo, and David A. B. Miller

    E-Print Network [OSTI]

    Miller, David A. B.

    Ge/SiGe Quantum Confined Stark Effect Modulators on Silicon James S. Harris, Yu-Hsuan Kuo bandwidth have been demonstrated [4]. 2. Quantum well design Ge is an indirect band gap material, but it has. In order to have good quantum confinement, SiGe barriers are used since Si and Ge have a very high direct

  20. Upgrade of CEBAF from 6-GeV To 12-GeV: Status

    SciTech Connect (OSTI)

    Harwood, Leigh H.

    2013-04-01T23:59:59.000Z

    The CEBAF accelerator is being upgraded from 6 GeV to 12 GeV by the US Department of Energy. The accelerator upgrade is being done within the existing tunnel footprint. The accelerator upgrade includes: 10 new srfbased high-performance cryomodules plus RF systems, doubling the 2K helium plants capability, upgrading the existing beamlines to operate at nearly double the original performance envelope, and adding a beamline to a new experimental area. Construction is over 75% complete with final completion projected for late FY13. Details of the upgrade and status of the work will be presented.

  1. Interface and nanostructure evolution of cobalt germanides on Ge(001)

    SciTech Connect (OSTI)

    Grzela, T., E-mail: grzela@ihp-microelectronics.com; Schubert, M. A. [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); Koczorowski, W. [London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London, WC1H 0AH,United Kingdom (United Kingdom); Institute of Physics, Poznan University of Technology, Nieszawska 13A, 60-965 Poznan (Poland); Capellini, G. [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); Dipartimento di Scienze, Università degli Studi Roma Tre, I-00146 Roma (Italy); Czajka, R. [Institute of Physics, Poznan University of Technology, Nieszawska 13A, 60-965 Poznan (Poland); Radny, M. W. [Institute of Physics, Poznan University of Technology, Nieszawska 13A, 60-965 Poznan (Poland); School of Mathematical and Physical Sciences, The University of Newcastle, University Drive, Callaghan NSW, 2308 (Australia); Curson, N.; Schofield, S. R. [London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London, WC1H 0AH,United Kingdom (United Kingdom); Schroeder, T. [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); BTU Cottbus, Konrad-Zuse Str. 1, 03046 Cottbus (Germany)

    2014-02-21T23:59:59.000Z

    Cobalt germanide (Co{sub x}Ge{sub y}) is a candidate system for low resistance contact modules in future Ge devices in Si-based micro and nanoelectronics. In this paper, we present a detailed structural, morphological, and compositional study on Co{sub x}Ge{sub y} formation on Ge(001) at room temperature metal deposition and subsequent annealing. Scanning tunneling microscopy and low energy electron diffraction clearly demonstrate that room temperature deposition of approximately four monolayers of Co on Ge(001) results in the Volmer Weber growth mode, while subsequent thermal annealing leads to the formation of a Co-germanide continuous wetting layer which evolves gradually towards the growth of elongated Co{sub x}Ge{sub y} nanostructures. Two types of Co{sub x}Ge{sub y} nanostructures, namely, flattop- and ridge-type, were observed and a systematic study on their evolution as a function of temperature is presented. Additional transmission electron microscopy and x-ray photoemission spectroscopy measurements allowed us to monitor the reaction between Co and Ge in the formation process of the Co{sub x}Ge{sub y} continuous wetting layer as well as the Co{sub x}Ge{sub y} nanostructures.

  2. SiGe thin-film structures for solar cells

    SciTech Connect (OSTI)

    Bremond, G.; Daami, A.; Laugier, A. [Inst. National des Sciences Appliquees de Lyon, Villeurbanne (France). Lab. de Physique de la Matiere] [and others

    1998-12-31T23:59:59.000Z

    In order to study their applicability as the active base material in Si thin crystalline film solar cell technology, SiGe relaxed layers grown by Liquid Phase Epitaxy (LPE) and Chemical Vapor Deposition (CVD) on Si substrates are investigated by optical and electrical measurements (TEM, EXD, PL, EBIC). The main results of this work is to point out the improvement of the SiGe active base layer by using smooth Ge graded SiGe buffer layer and remote plasma hydrogenation. TEM, EXD, PL experiments show the effect of the Ge graded buffer layer grown using LPE, by confining the threading dislocations in the SiGe buffer layer close to the Si/SiGe interface. EBIC measurements reveal low recombination activity of dislocations at 300 K providing the diffusion length exceeds the 15 {micro}m layer thickness. The enhanced luminescence of SiGe near bandgap indicates that remote plasma hydrogenation induces a decrease of the non-radiative recombination pathways due to dislocations on CVD layers where defect recombinations dominate as indicated by EBIC measurements. This study points out the importance of controlling relaxed SiGe layers with good minority carrier recombination quality as a key issue for the optimization of new SiGe/Si based solar cells.

  3. Patent Record Announcement | GE Global Research

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible for RenewableSpeedingBiomassPPPO WebsitePalms Village ResortEnergyL L 2PatentGE's E.

  4. Crowdsourcing Software Announcement | GE Global Research

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power Administration would likeConstitution4 Department of EnergyCross-SectorDepartment ofGE, MIT

  5. Crowdsourcing Software Award | GE Global Research

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power Administration would likeConstitution4 Department of EnergyCross-SectorDepartment ofGE,

  6. Brazil Technology Center | GE Global Research

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

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

  7. Study of the low-lying states of Ge2 and Ge2 using negative ion zero electron kinetic energy spectroscopy

    E-Print Network [OSTI]

    Neumark, Daniel M.

    Study of the low-lying states of Ge2 and Ge2 using negative ion zero electron kinetic energy The low-lying states of Ge2 and Ge2 are probed using negative ion zero electron kinetic energy ZEKE spectroscopy. The ZEKE spectrum of Ge2 yields an electron affinity of 2.035 0.001 eV for Ge2, as well as term

  8. A New Look at the Galactic Diffuse GeV

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    ;Gamma-ray Detectors from 10s MeV to 100s GeV Gamma-rays' trajectories cannot be directly detected #12;Gamma-ray Detectors from 10s MeV to 100s GeV Gamma-rays' trajectories cannot be directly detected Physics 1 #12;Overview Diffuse gamma-ray emission The Galactic diffuse gamma-ray GeV excess Discussion

  9. Structure and vibrations of different charge Ge impurity in ?-quartz

    SciTech Connect (OSTI)

    Kislov, A. N., E-mail: a.n.kislov@urfu.ru; Mikhailovich, A. P., E-mail: a.n.kislov@urfu.ru; Zatsepin, A. F., E-mail: a.n.kislov@urfu.ru [Ural Federal University, 19 Mira St., Yekaterinburg, 620002 (Russian Federation)

    2014-10-21T23:59:59.000Z

    Atomic structure and localized vibrations of ??SiO{sub 2}:Ge are studied using computer modeling techniques. The simulation was carried out by the lattice dynamics calculation of the local density of vibrational states. Local structures parameters are calculated, localized symmetrized vibrations frequency caused by Ge impurity in different charge states are defined. The movements of atoms located near Ge impurity are analyzed and their contribution into localized vibrations of different type is evaluated.

  10. Computing with living hardware K.A. Haynes, M.L. Broderick, A.D. Brown, T.L. Butner, L. Harden, L. Heard, E. Jessen, K. Malloy, B. Ogden,

    E-Print Network [OSTI]

    Campbell, A. Malcolm

    Computing with living hardware K.A. Haynes, M.L. Broderick, A.D. Brown, T.L. Butner, L. Harden, L. Heard, E. Jessen, K. Malloy, B. Ogden, S. Rosemond, S. Simpson, E. Zwack, A. Malcolm Campbell, T

  11. Structural and phonon transmission study of Ge-Au-Ge eutectically bonded interfaces

    SciTech Connect (OSTI)

    Knowlton, W.B. [Univ. of California, Berkeley, CA (United States). Dept. of Materials Science and Mineral Engineering]|[Lawrence Berkeley Lab., CA (United States). Materials Sciences Div.

    1995-07-01T23:59:59.000Z

    This thesis presents a structural analysis and phonon transparency investigation of the Ge-Au-Ge eutectic bond interface. Interface development was intended to maximize the interfacial ballistic phonon transparency to enhance the detection of the dark matter candidate WIMPs. The process which was developed provides an interface which produces minimal stress, low amounts of impurities, and insures Ge lattice continuity through the interface. For initial Au thicknesses of greater than 1,000 {angstrom} Au per substrate side, eutectic epitaxial growth resulted in a Au dendritic structure with 95% cross sectional and 90% planar Au interfacial area coverages. In sections in which Ge bridged the interface, lattice continuity across the interface was apparent. Epitaxial solidification of the eutectic interface with initial Au thicknesses < 500 A per substrate side produced Au agglomerations thereby reducing the Au planar interfacial area coverage to as little as 30%. The mechanism for Au coalescence was attributed to lateral diffusion of Ge and Au in the liquid phase during solidification. Phonon transmission studies were performed on eutectic interfaces with initial Au thicknesses of 1,000 {angstrom}, 500 {angstrom}, and 300 {angstrom} per substrate side. Phonon imaging of eutectically bonded samples with initial Au thicknesses of 300 {angstrom}/side revealed reproducible interfacial percent phonon transmissions from 60% to 70%. Line scan phonon imaging verified the results. Phonon propagation TOF spectra distinctly showed the predominant phonon propagation mode was ballistic. This was substantiated by phonon focusing effects apparent in the phonon imaging data. The degree of interface transparency to phonons and resulting phonon propagation modes correlate with the structure of the interface following eutectic solidification. Structural studies of samples with initial Au thickness of 1,000 {angstrom}/side appear to correspond with the phonon transmission study.

  12. GE Technology to Help Canada Province Meet Growing Energy Needs

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

    funding and collaboration models at its European Global Research Center near Munich, Germany. Mark Little, GE's Senior Vice President and Chief Technology Officer, and thought...

  13. Limitless Hot Gas Path Cooling Design | GE Global Research

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

    Organization at GE Global Research, one such potent combination already taking shape is Additive Manufacturing and High Pressure Turbine Blade Cooling. Additive Manufacturing...

  14. GE researchers perform simulations in pursuit of more efficient...

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

    GE researchers perform simulations in pursuit of more efficient jet engines and wind turbines Author: John Spizzirri . July 1, 2014 Printer-friendly version The recent addition of...

  15. How Will We Explore Earth's Final Frontier? | GE Global Research

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

    see how technology is helping us understand, utilize and protect the last frontier on earth. At GE Global Research's Rio de Janiero location, researchers are developing...

  16. Media Advisory - Jefferson Lab 12 GeV Upgrade Groundbreaking...

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

    for its 310 million 12 GeV Upgrade project. When: Tuesday, April 14, 2009. Where: CEBAF Center, Thomas Jefferson National Accelerator Facility, 12000 Jefferson Avenue,...

  17. GE's Arnie Lund Discusses User Experience at an Industrial Scale...

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

    at an Industrial Scale Arnie Lund, manager of the UX Industrial Innovation Lab at GE Global Research in San Ramon, Calif, recently spoke to the Farstuff Podcast about...

  18. approaching cryogenic ge: Topics by E-print Network

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

    Very low Weinreb, Sander 2 Draft 040509 A new high-background-rejection dark matter Ge cryogenic Computer Technologies and Information Sciences Websites Summary: Draft...

  19. Titan propels GE wind turbine research into new territory | ornl...

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

    Titan propels GE wind turbine research into new territory January 17, 2014 The amount of global electricity supplied by wind, the world's fastest growing energy source, is expected...

  20. Distinct Fermi Surface Topology and Nodeless Superconducting Gap in a Tl0:58Rb0:42Fe1:72Se2 Superconductor

    E-Print Network [OSTI]

    Tian, Weidong

    -based superconductors reported so far. The Fermi surface around the M point shows a nearly isotropic superconducting gap) superconductors [6]. It is important to explore whether the high-Tc superconductiv- ity mechanism in this new FeDistinct Fermi Surface Topology and Nodeless Superconducting Gap in a ðTl0:58Rb0:42�Fe1:72Se2

  1. Niobium-Arsenic Zintl Phases: A6NbAs5 (A ) K, Rb, Cs), K6NbTlAs4, and K8NbPbAs5 with Edge-Bridged Niobium-Centered Tetrahedra of

    E-Print Network [OSTI]

    Niobium-Arsenic Zintl Phases: A6NbAs5 (A ) K, Rb, Cs), K6NbTlAs4, and K8NbPbAs5 with Edge-Bridged Niobium-Centered Tetrahedra of Arsenic, [NbAs4M]n- Where M ) As, Tl, Pb Franck Gascoin and Slavi C. Sevov into exploring this apparent readiness of niobium to react with arsenic and form tetrahedral species, and more

  2. Electronic dose conversion technique using a NaI(Tl) detector for assessment of exposure dose rate from environmental radiation

    SciTech Connect (OSTI)

    Cho, G.; Kim, H.K. [Korea Advanced Inst. of Science and Technology, Taejon (Korea, Republic of)] [Korea Advanced Inst. of Science and Technology, Taejon (Korea, Republic of); Woo, H.; Oh, G. [Korea Electric Power Research Inst., Taejon (Korea, Republic of)] [Korea Electric Power Research Inst., Taejon (Korea, Republic of); Ha, D.K. [Samchang Enterprise Co., Anyang (Korea, Republic of)] [Samchang Enterprise Co., Anyang (Korea, Republic of)

    1998-06-01T23:59:59.000Z

    An electronic dose conversion technique to assess the exposure dose rate due to environmental radiation especially from terrestrial sources was developed. For a 2 x 2 inch cylindrical NaI(Tl) scintillation detector, pulse-height spectra were obtained for gamma-rays of energy up to 3 MeV by Monte Carlo simulation. Based on the simulation results and the experimentally fitted energy resolution, dose conversion factors were calculated by a numerical decomposition method. These calculated dose conversion factors were, then, electronically implemented to a developed dose conversion unit (DCU) which is a microprocessor-controlled single channel analyzer (SCA) with variable discrimination levels. The simulated spectra were confirmed by measurement of several monoenergetic gamma spectra with a multichannel analyzer (MCA). The converted exposure dose rates from the implemented dose conversion algorithm in the DCU were also evaluated for a field test in the vicinity of the nuclear power plant at Kori as well as for several standard sources, and the results were in good agreement with separate measurement by a high pressure ionization chamber (HPIC) within a 6.4% deviation.

  3. Structural and optical properties of GaAs-based heterostructures with Ge and Ge/InGaAs quantum wells

    SciTech Connect (OSTI)

    Aleshkin, V. Ya.; Dubinov, A. A., E-mail: sanya@ipm.sci-nnov.ru; Drozdov, M. N. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation); Zvonkov, B. N. [Nizhni Novgorod State University, Research Physical Technical Institute (Russian Federation); Kudryavtsev, K. E.; Tonkikh, A. A.; Yablonskiy, A. N. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation); Werner, P. [Max Planck Institute of Microstructure Physics (Germany)

    2013-05-15T23:59:59.000Z

    GaAs-based heterostructures with Ge and Ge/InGaAs quantum wells are grown by laser-assisted sputtering. Structural and optical studies of the heterostructures are carried out. A broad photoluminescence line is observed in the wavelength range from 1300 to 1650 nm. The line corresponds to indirect transitions in the momentum space of the Ge quantum wells and to transitions between the In{sub 0.28}Ga{sub 0.72}As and Ge layers, indirect in coordinate space, but direct in momentum space.

  4. Serial and parallel Si, Ge, and SiGe direct-write with scanning probes and conducting stamps

    SciTech Connect (OSTI)

    Vasko, Stephanie E.; Kapetanovic, Adnan; Talla, Vamsi; Brasino, Michael D.; Zhu, Zihua; Scholl, Andreas; Torrey, Jessica D.; Rolandi, Marco

    2011-05-16T23:59:59.000Z

    Precise materials integration in nanostructures is fundamental for future electronic and photonic devices. We demonstrate Si, Ge, and SiGe nanostructure direct-write with deterministic size, geometry, and placement control. The biased probe of an atomic force microscope (AFM) reacts diphenylsilane or diphenylgermane to direct-write carbon-free Si, Ge, and SiGe nano and heterostructures. Parallel directwrite is available on large areas by substituting the AFM probe with conducting microstructured stamps. This facile strategy can be easily expanded to a broad variety of semiconductor materials through precursor selection.

  5. Shell model description of Ge isotopes

    E-Print Network [OSTI]

    J. G. Hirsch; P. C. Srivastava

    2012-04-12T23:59:59.000Z

    A shell model study of the low energy region of the spectra in Ge isotopes for $38\\leq N\\leq 50$ is presented, analyzing the excitation energies, quadrupole moments, $B(E2)$ values and occupation numbers. The theoretical results have been compared with the available experimental data. The shell model calculations have been performed employing three different effective interactions and valence spaces.We have used two effective shell model interactions, JUN45 and jj44b, for the valence space $f_{5/2} \\, p \\,g_{9/2}$ without truncation. To include the proton subshell $f_{7/2}$ in valence space we have employed the $fpg$ effective interaction due to Sorlin {\\it et al.}, with $^{48}$Ca as a core and a truncation in the number of excited particles.

  6. 3 GeV Injector Design Handbook

    SciTech Connect (OSTI)

    Wiedemann, H.; /SLAC, SSRL

    2009-12-16T23:59:59.000Z

    This Design Handbook is intended to be the main reference book for the specifications of the 3 GeV SPEAR booster synchrotron project. It is intended to be a consistent description of the project including design criteria, key technical specifications as well as current design approaches. Since a project is not complete till it's complete changes and modifications of early conceptual designs must be expected during the duration of the construction. Therefore, this Design Handbook is issued as a loose leaf binder so that individual sections can be replaced as needed. Each page will be dated to ease identification with respect to latest revisions. At the end of the project this Design Handbook will have become the 'as built' reference book of the injector for operations and maintenance personnel.

  7. Nanostructure and infrared photoluminescence of nanocrystalline Ge formed by reduction of Si0.75Ge0.25O2 Si0.75Ge0.25 using various H2 pressures

    E-Print Network [OSTI]

    Nanostructure and infrared photoluminescence of nanocrystalline Ge formed by reduction of Si0.75Ge0.25O2 ÕSi0.75Ge0.25 using various H2 pressures Gianni Taraschi,a) Sajan Saini, Wendy W. Fan, Lionel C Ge in SiO2 was synthesized by the reduction of Si0.75Ge0.25O2 with H2 , at various annealing

  8. High Capacity Li Ion Battery Anodes Using Ge Nanowires

    E-Print Network [OSTI]

    Cui, Yi

    High Capacity Li Ion Battery Anodes Using Ge Nanowires Candace K. Chan, Xiao Feng Zhang, and Yi Cui efficiency > 99%. Structural characterization revealed that the Ge nanowires remain intact and connected nanowire anodes are promising candidates for the development of high-energy-density lithium batteries

  9. Project-X Workshop 120 GeV Target

    E-Print Network [OSTI]

    McDonald, Kirk

    Project-X Workshop 120 GeV Target Summary ­ Workshop # 1 N. Simos, M. Martens #12;Project-X Workshop Challenges OVERVIEW Driven by 120 GeV/170 TP-per-spill · Short Term: 170 TPs/2us-spill (materials an existing 400 kW facility ­ Constraints #12;Project-X Workshop Presentations - Discussions · Engineering

  10. Band-engineered Ge-on-Si lasers

    E-Print Network [OSTI]

    Liu, Jifeng

    We report optically-pumped Ge-on-Si lasers with direct gap emission near 1600 nm at room temperature. The Ge-on-Si material was band-engineered by tensile strain and n-type doping to compensate the energy difference between ...

  11. Excess vacancies in high energy ion implanted SiGe

    SciTech Connect (OSTI)

    Koegler, R.; Muecklich, A.; Skorupa, W.; Peeva, A.; Kuznetsov, A. Yu.; Christensen, J. S.; Svensson, B. G. [Forschungszentrum Rossendorf, PF 510119, D-01314 Dresden (Germany); Institute of Solid State Physics BAS, Boulevard Tzarigradsko Chaussee 72, 1784 Sofia (Bulgaria); Deparment of Physics, University of Oslo, P.O. Box 1048 Blindern, NO-0316 Oslo (Norway); Center for Materials Science and Nanotechnology, University of Oslo, P.O. Box 1048 Blindern, NO-0316 Oslo (Norway)

    2007-02-01T23:59:59.000Z

    Excess vacancies generated by high energy implantation with 1.2 MeV Si{sup +} and 2 MeV Ge{sup +} ions in SiGe were investigated after rapid thermal annealing at 900 degree sign C. Excess vacancies were probed by decoration with Cu and measuring the Cu profile by secondary ion mass spectrometry. Cross section transmission electron microscopy of cleaved specimen enabled to visualize nanocavities resulting from agglomeration of excess vacancies. The ion-induced damage in SiGe increases with increasing Ge fraction of the alloy. The amorphization threshold decreases and the extension of a buried amorphous layer increases for given implantation and annealing conditions. In contrast to ballistic simulations of excess defect generation where perfect local self-annihilation is assumed the concentrations of excess vacancies and excess interstitials in SiGe increase with increasing Ge fraction. The main contribution to the high excess vacancy concentration in SiGe results from the inefficient recombination of vacancies and interstitials. The widely used +1 model describing the ion-induced damage in Si is not valid for SiGe.

  12. Volcanic rifting at Martian grabens Daniel Me`ge,1

    E-Print Network [OSTI]

    Mege, Daniel

    Volcanic rifting at Martian grabens Daniel Me`ge,1 Anthony C. Cook,2,3 Erwan Garel,4 Yves: Solar System Objects: Mars; 8121 Tectonophysics: Dynamics, convection currents and mantle plumes; 8010: Me`ge, D., A. C. Cook, E. Garel, Y. Lagabrielle, and M.-H. Cormier, Volcanic rifting at Martian

  13. Excess carrier lifetimes in Ge layers on Si

    SciTech Connect (OSTI)

    Geiger, R., E-mail: richard.geiger@psi.ch, E-mail: hans.sigg@psi.ch; Sigg, H., E-mail: richard.geiger@psi.ch, E-mail: hans.sigg@psi.ch [Laboratory for Micro- and Nanotechnology, Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Frigerio, J.; Chrastina, D.; Isella, G. [L-NESS, Dipartimento di Fisica del Politecnico di Milano, Via Anzani 42, 22100 Como (Italy); Süess, M. J. [Laboratory for Micro- and Nanotechnology, Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Laboratory for Nanometallurgy, Department of Materials Science, ETH Zurich, 8093 Zurich (Switzerland); Scientific Center for Optical and Electron Microscopy (SCOPEM), ETH Zurich, 8093 Zurich (Switzerland); Spolenak, R. [Laboratory for Nanometallurgy, Department of Materials Science, ETH Zurich, 8093 Zurich (Switzerland); Faist, J. [Institute for Quantum Electronics, ETH Zurich, 8093 Zurich (Switzerland)

    2014-02-10T23:59:59.000Z

    The excess charge carrier lifetimes in Ge layers grown on Si or germanium-on-insulator are measured by synchrotron based pump-probe transmission spectroscopy. We observe that the lifetimes do not strongly depend on growth parameters and annealing procedure, but on the doping profile. The defect layer at the Ge/Si interface is found to be the main non-radiative recombination channel. Therefore, the longest lifetimes in Ge/Si (2.6?ns) are achieved in sufficiently thick Ge layers with a built-in field, which repels electrons from the Ge/Si interface. Longer lifetimes (5.3?ns) are obtained in overgrown germanium-on-insulator due to the absence of the defective interface.

  14. Structural phase transitions on the nanoscale: The crucial pattern in the phase-change materials Ge2Sb2Te5 and GeTe

    E-Print Network [OSTI]

    Structural phase transitions on the nanoscale: The crucial pattern in the phase-change materials Ge2Sb2Te5 and GeTe J. Akola1,2 and R. O. Jones1 1Institut für Festkörperforschung, Forschungszentrum to characterize the amorphous structure of the prototype materials Ge2Sb2Te5 and GeTe. In both, there is long

  15. III International Conference on SiGe(C) Epitaxy and Heterostructures, NM, Mar. 2003 SiGe Single-Hole Transistor Fabricated by AFM Oxidation and Epitaxial Regrowth

    E-Print Network [OSTI]

    III International Conference on SiGe(C) Epitaxy and Heterostructures, NM, Mar. 2003 110 SiGe Single, West Lafayette, IN 47907, U.S.A. Nanodevices on Si/SiGe heterostructures are of growing interest [1 the performance of the devices. In this paper, we demonstrate a reproducible single-hole transistor SiGe device

  16. The role of straining and morphology in thermal conductivity of a set of SiGe superlattices and biomimetic SiGe nanocomposites

    E-Print Network [OSTI]

    Tomar, Vikas

    The role of straining and morphology in thermal conductivity of a set of Si­Ge superlattices and biomimetic Si­Ge nanocomposites This article has been downloaded from IOPscience. Please scroll down to see and morphology in thermal conductivity of a set of Si­Ge superlattices and biomimetic Si­Ge nanocomposites Vikas

  17. On atomic structure of Ge huts growing on the Ge/Si(001) wetting layer

    SciTech Connect (OSTI)

    Arapkina, Larisa V.; Yuryev, Vladimir A. [A. M. Prokhorov General Physics Institute of the Russian Academy of Sciences, 38 Vavilov Street, Moscow, 119991 (Russian Federation)] [A. M. Prokhorov General Physics Institute of the Russian Academy of Sciences, 38 Vavilov Street, Moscow, 119991 (Russian Federation)

    2013-09-14T23:59:59.000Z

    Structural models of growing Ge hut clusters—pyramids and wedges—are proposed on the basis of data of recent STM investigations of nucleation and growth of Ge huts on the Si(001) surface in the process of molecular beam epitaxy. It is shown that extension of a hut base along <110> directions goes non-uniformly during the cluster growth regardless of its shape. Growing pyramids, starting from the second monolayer, pass through cyclic formation of slightly asymmetrical and symmetrical clusters, with symmetrical ones appearing after addition of every fourth monolayer. We suppose that pyramids of symmetrical configurations composed by 2, 6, 10, etc., monolayers over the wetting layer are more stable than asymmetrical ones. This might explain less stability of pyramids in comparison with wedges in dense arrays forming at low temperatures of Ge deposition. Possible nucleation processes of pyramids and wedges on wetting layer patches from identical embryos composed by 8 dimers through formation of 1 monolayer high 16-dimer nuclei different only in their symmetry is discussed. Schematics of these processes are presented. It is concluded from precise STM measurements that top layers of wetting layer patches are relaxed when huts nucleate on them.

  18. Ratio of jet cross sections at root s=630 GeV and 1800 GeV

    E-Print Network [OSTI]

    Baringer, Philip S.; Bean, Alice; Coppage, Don; Hebert, C.

    2001-03-01T23:59:59.000Z

    The DO Collaboration has measured the inclusive jet cross section in (p) over barp collisions at roots = 630 GeV. The results for pseudorapidities \\ eta \\ < 0.5 are combined with our previous results at roots = 1800 GeV ...

  19. Ion Implanted Ge:B Far Infrard Blocked Impurity Band Detectors

    E-Print Network [OSTI]

    Beeman, J.W.; Goyal, S.; Reichertz, L.A.; Haller, E.E.

    2008-01-01T23:59:59.000Z

    +16 1.E+15 1.E+14 Depth into Ge Crystal Surface (Å) Figure 5devices does not match that of Ge:Ga photoconductors, whichimplants or stacking devices) Ge IBIB detectors will reach

  20. ALFVEN-WAVE OSCILLATIONS IN A SPHERE, WITH APPLICATIONS TO ELECTRON-HOLE DROPS IN Ge

    E-Print Network [OSTI]

    Markiewicz, R.S.

    2011-01-01T23:59:59.000Z

    Rev. B 13,4626 (1976). For Ge(4:2) m is the average of thediscussed for EHD in unstressed Ge (B II )TO ELECI'RON-OOLE DROPS IN Ge R. S. Markiewicz January 1978

  1. NUCLEATION PHENOMENA IN THE FORMATION OF ELECTRON-HOLE DROPS IN Ge

    E-Print Network [OSTI]

    Westervelt, R.M.

    2010-01-01T23:59:59.000Z

    lO cjl(K) Symbol erg cm ) Ge - 0.064 T2 Ref. x x Si Ref. T2constructed the ultra-sensitive Ge photodetector which wasand method of mounting. The Ge sample is electrically and

  2. Photo-oxidation of Ge Nanocrystals: Kinetic Measurements by In Situ Raman Spectroscopy

    E-Print Network [OSTI]

    2008-01-01T23:59:59.000Z

    Photo-oxidation of Ge Nanocrystals: Kinetic Measurements byBerkeley, CA, 94720 ABSTRACT Ge nanocrystals are formed inthe Raman spectra of the Ge nanocrystals in-situ. The

  3. Ferromagnetism in Mn-Implanted Epitaxially Grown Ge on Si(100)

    E-Print Network [OSTI]

    Guchhait, S.

    2011-01-01T23:59:59.000Z

    segregation in Mn-doped Ge”, Journal of Applied Physics 101,Room-temperature ferromagnetism in Ge 1-x Mn x nanowires”,BC high-?/metal gate Ge/C alloy pMOSFETs fabricated directly

  4. Origins of low resistivity and Ge donor level in Ge ion-implanted ZnO bulk single crystals

    SciTech Connect (OSTI)

    Kamioka, K.; Oga, T.; Izawa, Y.; Kuriyama, K. [College of Engineering and Research Center of Ion Beam Technology, Hosei University Koganei, Tokyo 184-8584 (Japan); Kushida, K. [Departments of Arts and Sciences, Osaka Kyoiku University Kashiwara, Osaka 582-8582 (Japan)

    2013-12-04T23:59:59.000Z

    The energy level of Ge in Ge-ion implanted ZnO single crystals is studied by Hall-effect and photoluminescence (PL) methods. The variations in resistivity from ?10{sup 3} ?cm for un-implanted samples to ?10{sup ?2} ?cm for as-implanted ones are observed. The resistivity is further decreased to ?10{sup ?3} ?cm by annealing. The origins of the low resistivity are attributed to both the zinc interstitial (Zn{sub i}) related defects and the electrical activated Ge donor. An activation energy of Ge donors estimated from the temperature dependence of carrier concentration is 102 meV. In PL studies, the new peak at 372 nm (3.33 eV) related to the Ge donor is observed in 1000 °C annealed samples.

  5. GeO{sub 2}/Ge structure submitted to annealing in deuterium: Incorporation pathways and associated oxide modifications

    SciTech Connect (OSTI)

    Bom, N. M., E-mail: nicolau.bom@ufrgs.br [PGMICRO, UFRGS, 91509-900 Porto Alegre, Rio Grande do Sul (Brazil); Soares, G. V.; Hartmann, S.; Bordin, A. [Instituto de Física, UFRGS, 91509-900 Porto Alegre, Rio Grande do Sul (Brazil); Radtke, C. [Instituto de Química, UFRGS, 91509-900 Porto Alegre, Rio Grande do Sul (Brazil)

    2014-10-06T23:59:59.000Z

    Deuterium (D) incorporation in GeO{sub 2}/Ge structures following D{sub 2} annealing was investigated. Higher D concentrations were obtained for GeO{sub 2}/Ge samples in comparison to their SiO{sub 2}/Si counterparts annealed in the same conditions. Oxygen vacancies produced during the annealing step in D{sub 2} constitute defect sites for D incorporation, analogous to defects at the SiO{sub 2}/Si interfacial region. Besides D incorporation, volatilization of the oxide layer is also observed as a consequence of D{sub 2} annealing, especially in the high temperature regime of the present study (>450?°C). In parallel to this volatilization, the stoichiometry and chemical structure of remnant oxide are modified as well. These results evidence the broader impact of forming gas annealing in dielectric/Ge structures with respect to SiO{sub 2}/Si counterparts.

  6. Atomic geometry of mixed Ge-Si dimers in the initial-stage growth of Ge on Si,,001...2 1 X. Chen* and D. K. Saldin

    E-Print Network [OSTI]

    Saldin, Dilano

    Atomic geometry of mixed Ge-Si dimers in the initial-stage growth of Ge on Si,,001...2 1 X. Chen quantitatively the geometry of mixed Ge-Si dimers on a single domain Si 001 2 1 surface by azimuthal scanning core-level photoelectron diffraction. By analyzing Ge 3d diffraction patterns from Ge/Si 001 at 0.1 ML

  7. GeV Emission from Collisional Magnetized Gamma Ray Bursts

    E-Print Network [OSTI]

    P. Mészáros; M. J. Rees

    2011-04-26T23:59:59.000Z

    Magnetic fields may play a dominant role in gamma-ray bursts, and recent observations by the Fermi satellite indicate that GeV radiation, when detected, arrives delayed by seconds from the onset of the MeV component. Motivated by this, we discuss a magnetically dominated jet model where both magnetic dissipation and nuclear collisions are important. We show that, for parameters typical of the observed bursts, such a model involving a realistic jet structure can reproduce the general features of the MeV and a separate GeV radiation component, including the time delay between the two. The model also predicts a multi-GeV neutrino component.

  8. Efficient tunable luminescence of SiGe alloy sheet polymers

    SciTech Connect (OSTI)

    Vogg, G.; Meyer, A. J.-P.; Miesner, C.; Brandt, M. S.; Stutzmann, M.

    2001-06-18T23:59:59.000Z

    Crystalline SiGe alloy sheet polymers were topotactically prepared from epitaxially grown calcium germanosilicide Ca(Si{sub 1{minus}x}Ge{sub x}){sub 2} precursor films in the whole composition range. These polygermanosilynes are found to be a well-defined mixture of the known siloxene and polygermyne sheet polymers with the OH groups exclusively bonded to silicon. The optical properties determined by photoluminescence and optical reflection measurements identify the mixed SiGe sheet polymers as direct semiconductors with efficient luminescence tunable in the energy range between 2.4 and 1.3 eV. {copyright} 2001 American Institute of Physics.

  9. Spin-polarized photoemission from SiGe heterostructures

    SciTech Connect (OSTI)

    Ferrari, A.; Bottegoni, F.; Isella, G.; Cecchi, S.; Chrastina, D.; Finazzi, M.; Ciccacci, F. [LNESS-Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano (Italy)

    2013-12-04T23:59:59.000Z

    We apply the principles of Optical Orientation to measure by Mott polarimetry the spin polarization of electrons photoemitted from different group-IV heterostructures. The maximum measured spin polarization, obtained from a Ge/Si{sub 0.31}Ge{sub 0.69} strained film, undoubtedly exceeds the maximum value of 50% attainable in bulk structures. The explanation we give for this result lies in the enhanced band orbital mixing between light hole and split-off valence bands as a consequence of the compressive strain experienced by the thin Ge layer.

  10. Optical absorption in highly-strained Ge/SiGe quantum wells: the role of ?-to-? scattering

    E-Print Network [OSTI]

    L. Lever; Z. Ikoni?; A. Valavanis; R. W. Kelsall; M. Myronov; D. R. Leadley; Y. Hu; N. Owens; F. Y. Gardes; G. T. Reed

    2013-02-28T23:59:59.000Z

    We report the observation of the quantum-confined Stark effect in Ge/SiGe multiple quantum well heterostructures grown on Si(0.22)Ge(0.78) virtual substrates. The large compressive strain in the Ge quantum well layers caused by the lattice mismatch with the virtual substrate results in a blue shift of the direct absorption edge, as well as a reduction in the \\Gamma-valley scattering lifetime because of strain-induced splittings of the conduction band valleys. We investigate theoretically the \\Gamma-valley carrier lifetimes by evaluating the \\Gamma-to-L and \\Gamma-to-\\Delta{} scattering rates in strained Ge/SiGe semiconductor heterostructures. These scattering rates are used to determine the lifetime broadening of excitonic peaks and the indirect absorption in simulated absorption spectra, which are compared with measured absorption spectra for quantum well structures with systematically-varied dimensions. We find that \\Gamma-to-\\Delta{} scattering is significant in compressively strained Ge quantum wells and that the \\Gamma-valley electron lifetime is less than 50 fs in the highly-strained structures reported here, where \\Gamma-to-\\Delta{} scattering accounted for approximately half of the total scattering rate.

  11. GE Store for Technology is Open for Business | GE Global Research

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) Environmental AssessmentsGeoffrey Campbell isOklahoma City, USAGE BBQ Center isThe GE

  12. Greatly improved interfacial passivation of in-situ high ? dielectric deposition on freshly grown molecule beam epitaxy Ge epitaxial layer on Ge(100)

    SciTech Connect (OSTI)

    Chu, R. L. [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Liu, Y. C.; Lee, W. C.; Huang, M. L.; Kwo, J., E-mail: raynien@phys.nthu.edu.tw, E-mail: mhong@phys.ntu.edu.tw [Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Lin, T. D.; Hong, M., E-mail: raynien@phys.nthu.edu.tw, E-mail: mhong@phys.ntu.edu.tw [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)

    2014-05-19T23:59:59.000Z

    A high-quality high-?/Ge interface has been achieved by combining molecule beam epitaxy grown Ge epitaxial layer and in-situ deposited high ? dielectric. The employment of Ge epitaxial layer has sucessfully buried and/or removed the residue of unfavorable carbon and native oxides on the chemically cleaned and ultra-high vacuum annealed Ge(100) wafer surface, as studied using angle-resolved x-ray photoelectron spectroscopy. Moreover, the scanning tunneling microscopy analyses showed the significant improvements in Ge surface roughness from 3.5?Å to 1?Å with the epi-layer growth. Thus, chemically cleaner, atomically more ordered, and morphologically smoother Ge surfaces were obtained for the subsquent deposition of high ? dielectrics, comparing with those substrates without Ge epi-layer. The capacitance-voltage (C-V) characteristics and low extracted interfacial trap density (D{sub it}) reveal the improved high-?/Ge interface using the Ge epi-layer approach.

  13. Atomic layer-by-layer oxidation of Ge (100) and (111) surfaces by plasma post oxidation of Al{sub 2}O{sub 3}/Ge structures

    SciTech Connect (OSTI)

    Zhang, Rui [School of Engineering, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-8656 (Japan) [School of Engineering, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-8656 (Japan); School of Electronic Science and Engineering, Nanjing University, 22 Hankou Road, Nanjing 210093 (China); Huang, Po-Chin; Lin, Ju-Chin; Takenaka, Mitsuru; Takagi, Shinichi [School of Engineering, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-8656 (Japan)] [School of Engineering, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-8656 (Japan)

    2013-02-25T23:59:59.000Z

    The ultrathin GeO{sub x}/Ge interfaces formed on Ge (100) and (111) surfaces by applying plasma post oxidation to thin Al{sub 2}O{sub 3}/Ge structures are characterized in detail using X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy. It is found that the XPS signals assigned to Ge 1+ and the 2+ states in the GeO{sub x} layers by post plasma oxidation have oscillating behaviors on Ge (100) surfaces in a period of {approx}0.3 nm with an increase in the GeO{sub x} thickness. Additionally, the oscillations of the signals assigned to Ge 1+ and 2+ states show opposite phase to each other. The similar oscillation behaviors are also confirmed on Ge (111) surfaces for Ge 1+ and 3+ states in a period of {approx}0.5 nm. These phenomena can be strongly regarded as an evidence of the atomic layer-by-layer oxidation of GeO{sub x}/Ge interfaces on Ge (100) and (111) surfaces.

  14. {open_quotes}Local texture, current flow, and superconductive transport properties of Tl1223 deposits on practical substrates{close_quotes}

    SciTech Connect (OSTI)

    Christen, D.K.; Specht, E.D.; Goyal, A. [and others

    1996-05-01T23:59:59.000Z

    Quantitative investigations of the crystal grain orientations and electrical transport properties of high temperature superconducting (HTS)TiBa{sub 2}Ca{sub 2}Cu{sub 3}O{sub 8+x} (Tl1223) deposits on polycrystalline substrates show that current flow comprises percolative networks of strongly-coupled material. Superconductive transport properties on different samples, on the same samples at different widths, and on samples with artificially-induced strong flux pinning defects confirm the nature of current flow, and suggest that these materials may be useful as a new class of HTS conductors.

  15. Investigations of segregation phenomena in highly strained Mn-doped Ge wetting layers and Ge quantum dots embedded in silicon

    SciTech Connect (OSTI)

    Prestat, E., E-mail: eric.prestat@gmail.com; Porret, C.; Favre-Nicolin, V.; Tainoff, D.; Boukhari, M.; Bayle-Guillemaud, P.; Jamet, M.; Barski, A., E-mail: andre.barski@cea.com [INAC, SP2M, CEA and Université Joseph Fourier, 17 rue des Martyrs, 38054 Grenoble (France)

    2014-03-10T23:59:59.000Z

    In this Letter, we investigate manganese diffusion and the formation of Mn precipitates in highly strained, few monolayer thick, Mn-doped Ge wetting layers and nanometric size Ge quantum dot heterostructures embedded in silicon. We show that in this Ge(Mn)/Si system manganese always precipitates and that the size and the position of Mn clusters (precipitates) depend on the growth temperature. At high growth temperature, manganese strongly diffuses from germanium to silicon, whereas decreasing the growth temperature reduces the manganese diffusion. In the germanium quantum dots layers, Mn precipitates are detected, not only in partially relaxed quantum dots but also in fully strained germanium wetting layers between the dots.

  16. Axial SiGe Heteronanowire Tunneling Field-Effect Transistors...

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

    tunneling field-effect transistors (TFETs), where on-state tunneling occurs in the Ge drain section, while off-state leakage is dominated by the Si junction in the source. Our...

  17. Technology makes reds "pop" in LED displays | GE Global Research

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

    Reveal and Energy Smart consumer brands, and Evolve(tm), GTx(tm), Immersion(tm), Infusion(tm), Lumination(tm), Albeo(tm) and Tetra commercial brands, all trademarks of GE....

  18. Taking on the World's Toughest Problems | GE Global Research

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

    direct write2square The GE Store for Technology is Open for Business 2-4-13-v-3d-printing-medical-devices Invention Factory: How Will The World Get Smaller? ...

  19. Carrier Density Modulation in Ge Heterostructure by Ferroelectric Switching

    SciTech Connect (OSTI)

    Ponath, Patrick [University of Texas at Austin; Fredrickson, Kurt [University of Texas at Austin; Posadas, Agham B. [University of Texas at Austin; Ren, Yuan [University of Texas at Austin; Vasudevan, Rama K [ORNL; Okatan, Mahmut Baris [ORNL; Jesse, Stephen [ORNL; Aoki, Toshihiro [Arizona State University; McCartney, Martha [Arizona State University; Smith, David J [Arizona State University; Kalinin, Sergei V [ORNL; Lai, Keji [University of Texas at Austin; Demkov, Alexander A. [University of Texas at Austin

    2015-01-01T23:59:59.000Z

    The development of nonvolatile logic through direct coupling of spontaneous ferroelectric polarization with semiconductor charge carriers is nontrivial, with many issues, including epitaxial ferroelectric growth, demonstration of ferroelectric switching, and measurable semiconductor modulation. Here we report a true ferroelectric field effect carrier density modulation in an underlying Ge(001) substrate by switching of the ferroelectric polarization in the epitaxial c-axis-oriented BaTiO3 (BTO) grown by molecular beam epitaxy (MBE) on Ge. Using density functional theory, we demonstrate that switching of BTO polarization results in a large electric potential change in Ge. Aberration-corrected electron microscopy confirms the interface sharpness, and BTO tetragonality. Electron-energy-loss spectroscopy (EELS) indicates the absence of any low permittivity interlayer at the interface with Ge. Using piezoelectric force microscopy (PFM), we confirm the presence of fully switchable, stable ferroelectric polarization in BTO that appears to be single domain. Using microwave impedance microscopy (MIM), we clearly demonstrate a ferroelectric field effect.

  20. Direct band gap narrowing in highly doped Ge

    E-Print Network [OSTI]

    Han, Zhaohong

    Direct band gap narrowing in highly doped n-type Ge is observed through photoluminescence measurements by determining the spectrum peak shift. A linear relationship between the direct band gap emission and carrier concentration ...

  1. Growth strategies to control tapering in Ge nanowires

    SciTech Connect (OSTI)

    Periwal, P.; Baron, T., E-mail: thierry.baron@cea.fr; Salem, B.; Bassani, F. [Laboratoire des Technologies de la Microelectronique (LTM), UMR 5129 CNRS-UJF, CEA Grenoble, 17 Rue des Martyrs, 38054 Grenoble (France); Gentile, P. [SiNaPs Laboratory SP2M, UMR-E, CEA/UJF-Grenoble 1, INAC, 38054 Grenoble (France)

    2014-04-01T23:59:59.000Z

    We report the effect of PH{sub 3} on the morphology of Au catalyzed Ge nanowires (NWs). Ge NWs were grown on Si (111) substrate at 400?°C in the presence of PH{sub 3}, using vapor-liquid-solid method by chemical vapor deposition. We show that high PH{sub 3}/GeH{sub 4} ratio causes passivation at NW surface. At high PH{sub 3} concentration phosphorous atoms attach itself on NW surface and form a self-protection coating that prevents conformal growth and leads to taper free nanostructures. However, in case of low PH{sub 3} flux the combination of axial and radial growth mechanism occurs resulting in conical structure. We have also investigated axial PH{sub 3}-intrinsic junctions in Ge NWs. The unusual NW shape is attributed to a combination of catalyzed, uncatalyzed and diffusion induced growth.

  2. Nanocrystalline Ge Flash Memories: Electrical Characterization and Trap Engineering

    E-Print Network [OSTI]

    Kan, Eric Win Hong

    Conventional floating gate non-volatile memories (NVMs) present critical issues for device scalability beyond the sub-90 nm node, such as gate length and tunnel oxide thickness reduction. Nanocrystalline germanium (nc-Ge) ...

  3. Discovery of Isotopes of Elements with Z $\\ge$ 100

    E-Print Network [OSTI]

    M. Thoennessen

    2012-03-09T23:59:59.000Z

    Currently, 163 isotopes of elements with Z $\\ge$ 100 have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  4. Ge-on-Si laser operating at room temperature

    E-Print Network [OSTI]

    Liu, Jifeng

    Monolithic lasers on Si are ideal for high-volume and large-scale electronic–photonic integration. Ge is an interesting candidate owing to its pseudodirect gap properties and compatibility with Si complementary metal oxide ...

  5. High-Speed Network Enables Industrial Internet | GE Global Research

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

    share on LinkedIn (Opens in new window) Click to share on Tumblr (Opens in new window) GE Unveils High-Speed Network Infrastructure to Connect Machines, Data and People at Light...

  6. GE Software Expert Julian Keith Loren Discusses Innovation and...

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

    GE Software Expert Julian Keith Loren Discusses Innovation and the Industrial Internet Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new window)...

  7. Technology "Relay Race" Against Cancer | GE Global Research

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

    GE Scientists in Technology "Relay Race" Against Cancer Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new window) Click to share (Opens in new...

  8. An Update on the Brazil Tech Center | GE Global Research

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

    desde meu ultimo update a voces sobre o Centro de Pesquisas da GE no Rio de Janeiro, Brasil e tambm minha terra natal 2011 foi um timo ano para mim. Depois de viver na...

  9. Construction progresses at GE's Oil & Gas Technology Center ...

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

    progressing at GE's newest research center, the Oil & Gas Technology Center in Oklahoma City Click to email this to a friend (Opens in new window) Share on Facebook (Opens...

  10. ECS Transactions 3, (7), 1211-1222 (2006) Characterization of Strained Si/SiGe with Raman, Pulsed MOS Capacitor

    E-Print Network [OSTI]

    Schroder, Dieter K.

    2006-01-01T23:59:59.000Z

    ECS Transactions 3, (7), 1211-1222 (2006) 1211 Characterization of Strained Si/SiGe with Raman silicon/relaxed SiGe/graded SiGe/Si samples. The effective generation lifetime depends on the defect defective SiGe. GOI statistical analysis shows worsening oxide breakdown as the Ge concentration in the SiGe

  11. The Jefferson Lab 12 GeV Upgrade

    E-Print Network [OSTI]

    McKeown, R D

    2010-01-01T23:59:59.000Z

    Construction of the 12 GeV upgrade to the Continuous Electron Beam Accelerator Facility (CEBAF) at the Thomas Jefferson National Accelerator Facility is presently underway. This upgrade includes doubling the energy of the electron beam to 12 GeV, the addition of a new fourth experimental hall, and the construction of upgraded detector hardware. An overview of this upgrade project is presented, along with highlights of the anticipated experimental program.

  12. The Jefferson Lab 12 GeV Upgrade

    E-Print Network [OSTI]

    R. D. McKeown

    2010-09-22T23:59:59.000Z

    Construction of the 12 GeV upgrade to the Continuous Electron Beam Accelerator Facility (CEBAF) at the Thomas Jefferson National Accelerator Facility is presently underway. This upgrade includes doubling the energy of the electron beam to 12 GeV, the addition of a new fourth experimental hall, and the construction of upgraded detector hardware. An overview of this upgrade project is presented, along with highlights of the anticipated experimental program.

  13. AC transport in p-Ge/GeSi quantum well in high magnetic fields

    SciTech Connect (OSTI)

    Drichko, I. L.; Malysh, V. A.; Smirnov, I. Yu.; Golub, L. E.; Tarasenko, S. A. [A.F. Ioffe Physical Technical Institute of Russian Academy of Sciences, 194021 St. Petersburg (Russian Federation); Suslov, A. V. [National High Magnetic Field Laboratory, Tallahassee, FL 32310 (United States); Mironov, O. A. [Warwick SEMINANO R and D Center, University of Warwick Science Park, Coventry CV4 7EZ (United Kingdom); Kummer, M.; Känel, H. von [Laboratorium für Festkörperphysik ETH Zürich, CH-8093 Zürich (Switzerland)

    2014-08-20T23:59:59.000Z

    The contactless surface acoustic wave technique is implemented to probe the high-frequency conductivity of a high-mobility p-Ge/GeSi quantum well structure in the regime of integer quantum Hall effect (IQHE) at temperatures 0.3–5.8 K and magnetic fields up to 18 T. It is shown that, in the IQHE regime at the minima of conductivity, holes are localized and ac conductivity is of hopping nature and can be described within the “two-site” model. The analysis of the temperature and magnetic-field-orientation dependence of the ac conductivity at odd filing factors enables us to determine the effective hole g-factor, |g{sub zz}|?4.5. It is shown that the in-plane component of the magnetic field leads to a decrease in the g-factor as well as increase in the cyclotron mass, which is explained by orbital effects in the complex valence band of germanium.

  14. Members of a workshop at the tenth IAYC Conference, July 7, 2006 1. ge -hak -te le -ber, ge -fil -te -fish: sha-bes iz a far -ge -ni -gn

    E-Print Network [OSTI]

    Finkel, Raphael

    A SUDE Members of a workshop at the tenth IAYC Conference, July 7, 2006 = 90 4 4 1. ge - hak - te le - ber, ge - fil - te - fish: sha- bes iz a far - ge - ni - gn 2. kha - le gri - vn, ku - gl yoykh: ku - men on di ma - khe - to - nem. 3. shtru - dl, tsi - mes, zi - se kalte: a su - de vos men vet ge

  15. Co silicide formation on SiGeC/Si and SiGe/Si layers R. A. Donatona)

    E-Print Network [OSTI]

    on the total strain energy in the layer and restricts the applications where high Ge concentrations are needed spectrometry, secondary ion mass spectroscopy SIMS , and four point probe for sheet resistance measure- ments

  16. GE & AE Extension Request Form, Version 7, Feb 2013, JC Program Change

    E-Print Network [OSTI]

    Escher, Christine

    GE & AE Extension Request Form, Version 7, Feb 2013, JC Program Change Pathway Today's Date to General English. How many sessions of GE do you wish to request? 1 2 3 4 (GE sessions are 5 weeks) How many GE hours do you wish to take? 21 hours 27 hours OR ____ I am a Pathway student, and I would like

  17. CTu2J.1.pdf CLEO Technical Digest OSA 2012 Light Emission in Ge Quantum Wells

    E-Print Network [OSTI]

    Miller, David A. B.

    CTu2J.1.pdf CLEO Technical Digest © OSA 2012 Light Emission in Ge Quantum Wells Edward T. Fei1 Engineering, Stanford University, Stanford, CA 94305, USA edfei@stanford.edu Abstract: We present the Ge/SiGe and electroluminescence show enhanced optical properties over bulk Ge. Further optical enhancement is observed in disk

  18. College of Engineering Partner Schools Australia Melbourne University, Melbourne GE3*

    E-Print Network [OSTI]

    Lee, Tonghun

    College of Engineering Partner Schools Australia Melbourne University, Melbourne ­ GE3* University of New South Wales, New South Wales ­ GE3* Austria Technical University of Vienna, Vienna - GE3* Chile Universidad del Bio Bio, Concepcion China Xiamen University, Xiamen ­ GE3* Denmark Aalborg University, Aalborg

  19. On the Comparison of Fisher Information of the Weibull and GE Distributions

    E-Print Network [OSTI]

    Kundu, Debasis

    On the Comparison of Fisher Information of the Weibull and GE Distributions Rameshwar D. Gupta exponen- tial (GE) and Weibull distributions for complete and Type-I censored observations. Fisher is much more than the GE distribution. We compute the total information of the Weibull and GE

  20. C-band side-entry Ge quantum-well electroabsorption modulator on SOI

    E-Print Network [OSTI]

    Miller, David A. B.

    C-band side-entry Ge quantum-well electroabsorption modulator on SOI operating at 1 V swing J. Modulation was due to the quantum-confined Stark effect from ten Ge/SiGe quantum wells epitaxially grown the totally internally reflecting air-SiGe interface and a frustrated total internal reflection from

  1. University of California and HRL Laboratories, LLC. All rights reserved. SiGe/Si SUPERLATTICE COOLERS

    E-Print Network [OSTI]

    © University of California and HRL Laboratories, LLC. All rights reserved. SiGe/Si SUPERLATTICE and characterization of SiGe/Si superlattice coolers are described. Superlattice structures were used to enhance for SiGe/Si superlattice coolers. SiGe is a good thermoelectric material for high temperature

  2. Strain Relaxation of SiGe on Compliant BPSG and Its Applications

    E-Print Network [OSTI]

    Strain Relaxation of SiGe on Compliant BPSG and Its Applications Haizhou Yin A DISSERTATION of SiGe on compliant borophosphosilicate glass (BPSG). Through modeling and experiments it has been shown that strain relaxation in the SiGe film can be induced by lateral expansion and buckling of the SiGe

  3. OPTIMIZATION OF a-SiGe BASED TRIPLE, TANDEM AND SINGLE-JUNCTION SOLAR Xunming Deng

    E-Print Network [OSTI]

    Deng, Xunming

    OPTIMIZATION OF a-SiGe BASED TRIPLE, TANDEM AND SINGLE-JUNCTION SOLAR CELLS Xunming Deng Department cells, all employing high- quality a-SiGe cells, are reviewed in this paper. Incorporating various improvements in device fabrication, the UT group fabricated 1) triple-junction a-Si/a-SiGe/a- SiGe solar cells

  4. SiGe virtual substrate HMOS transistor for analogue applications K. Michelakisa,*

    E-Print Network [OSTI]

    Papavassiliou, Christos

    SiGe virtual substrate HMOS transistor for analogue applications K. Michelakisa,* , S Abstract Silicon­germanium (SiGe) heterojunction metal-oxide-semiconductor field-effect transistors (SiGe design. The results suggest that the realisation of buried-channel SiGe n-HMOSFETs is feasible in MOS

  5. SiGe-On-Insulator (SGOI): Two Structures for CMOS Application

    E-Print Network [OSTI]

    SiGe-On-Insulator (SGOI): Two Structures for CMOS Application Zhiyuan Cheng,a) Jongwan Jung, b Massachusetts Avenue, Cambridge, MA 02141 a) E-mail: cheng@alum.MIT.EDU Abstract ­ Two SiGe-on-insulator (SGOI enhancement on both electron and hole mobilities. Keywords ­ strained-Si, SiGe, SiGe-on-Insulator, SGOI

  6. Strain-induced self-assembly of Ge nanodashes, nanodumbbells, and dot chains on Si(001)

    SciTech Connect (OSTI)

    Zhang, J. J. [Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstr. 20, 01069 Dresden (Germany) [Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstr. 20, 01069 Dresden (Germany); Centre for Quantum Computation and Communication Technology, School of Physics, University of New South Wales, Sydney, New South Wales 2052 (Australia); Schmidt, O. G. [Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstr. 20, 01069 Dresden (Germany) [Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstr. 20, 01069 Dresden (Germany); Center for Advancing Electronics Dresden, TU Dresden (Germany)

    2013-09-30T23:59:59.000Z

    We investigate the growth of self-assembled Ge nanostructures on top of embedded Ge nanowires on Si(001) substrates. Ge nanostructures, such as nanodashes, nanodumbbells, and dot chains are observed simply by tuning the growth temperature and thickness of the Si spacer between the Ge layers. The self-assembly process is governed by the surface strain fields generated by the embedded Ge nanowires and is well-described by our theoretical calculations. The catalyst-free and horizontal growth of such Ge nanostructures directly on Si(001) is attractive for investigating exotic transport properties through Si/Ge-based quantum devices.

  7. Background p(450 GeV/c)-p,d (NA51)

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    #12;#12;Background ' Open charm J / Drell-Yan #12;* p(450 GeV/c)-p,d (NA51) 208 16 p(200 Ge) 32 p(450 GeV/c)-A (A=C,Al,Cu,W) (NA38) 10101 10101010 652 3 4 B targetprojectile B(J/)/(AB)(nb) 5 4 3 Pb(208x158 GeV/c)-Pb (NA50) S(32x200 GeV/c)-U (NA38) p(200 GeV/c)-W (NA38) p(450 GeV/c)-A (A=p,d) (NA

  8. Photoluminescence and positron annihilation spectroscopy investigation of (Ge, Er) codoped Si oxides deposited by magnetron sputtering

    SciTech Connect (OSTI)

    Heng, C. L.; Chelomentsev, E.; Peng, Z. L.; Mascher, P. [Department of Engineering Physics and Centre for Emerging Device Technologies, McMaster University, Hamilton, Ontario L8S 4K1 (Canada); Simpson, P. J. [Department of Physics and Astronomy, University of Western Ontario, London, Ontario N6A 3K7 (Canada)

    2009-01-01T23:59:59.000Z

    We have investigated the nature of violet-blue emission from (Ge, Er) codoped Si oxides (Ge+Er+SiO{sub 2}) using photoluminescence (PL) and positron annihilation spectroscopy (PAS) measurements. The PL spectra and PAS analysis for a control Ge-doped SiO{sub 2} (Ge+SiO{sub 2}) indicate that Ge-associated neutral oxygen vacancies (Ge-NOV) are likely responsible for the major emission in the violet-blue band. For Ge+Er+SiO{sub 2}, both Ge-NOV and GeO color centers are believed to be responsible for the emission band. The addition of Er has a significant influence on the emission, which is discussed in terms of Er-concentration-related structural change in the Ge+Er+SiO{sub 2}.

  9. Valley splitting in Si quantum dots embedded in SiGe S. Srinivasan,1,2

    E-Print Network [OSTI]

    Rokhinson, Leonid

    Valley splitting in Si quantum dots embedded in SiGe S. Srinivasan,1,2 G. Klimeck,1,2 and L. P subband.4 Recently, calculations predicted that valley splitting in nar- row few nanometers SiGe/Si/SiGe that prediction, which has been explained12 by the disorders of the Si/SiGe interface and in the SiGe buffer

  10. Comparison of luminescent efficiency of InGaAs quantum well structures grown on Si, GaAs, Ge, and SiGe virtual substrate

    E-Print Network [OSTI]

    , and SiGe virtual substrate V. K. Yang, S. M. Ting, M. E. Groenert, M. T. Bulsara, M. T. Currie, C. W efficiency of InGaAs quantum wells on Si via SiGe interlayers, identical In0.2Ga0.8As quantum well structures metalorganic vapor deposition system. The substrates used include GaAs, Si, Ge, and SiGe virtual substrates

  11. TEM Study on the Evolution of Ge Nanocrystals in Si Oxide Matrix as a Function of Ge Concentration and the Si Reduction Process

    E-Print Network [OSTI]

    Chew, Han Guan

    Growth and evolution of germanium (Ge) nanocrystals embedded into a silicon oxide (SiO?) system have been studied based on the Ge content of co-sputtered Ge-SiO? films using transmission electron microscopy (TEM) and X-ray ...

  12. Jefferson Lab 12 GeV CEBAF Upgrade

    SciTech Connect (OSTI)

    Claus Rode

    2010-04-01T23:59:59.000Z

    The existing continuous electron beam accelerator facility (CEBAF) at Thomas Jefferson National Accelerator Facility (TJNAF) is a 5-pass, recirculating cw electron Linac operating at ~6 GeV and is devoted to basic research in nuclear physics. The 12 GeV CEBAF Upgrade is a $310 M project, sponsored by the Department of Energy (DOE) Office of Nuclear Physics, that will expand its research capabilities substantially by doubling the maximum energy and adding major new experimental apparatus. The project received construction approval in September 2008 and has started the major procurement process. The cryogenic aspects of the 12 GeV CEBAF Upgrade includes: doubling the accelerating voltages of the Linacs by adding ten new high-performance, superconducting radiofrequency (SRF) cryomodules (CMs) to the existing 42 1/4 cryomodules; doubling of the 2 K cryogenics plant; and the addition of eight superconducting magnets.

  13. S5 0716+714 : GeV variability study

    E-Print Network [OSTI]

    Rani, B; Lott, B; Fuhrmann, L; Zensus, J A

    2013-01-01T23:59:59.000Z

    The GeV observations by Fermi-LAT give us the opportunity to characterize the high-energy emission (100 MeV - 300 GeV) variability properties of the BL Lac object S5 0716+714. In this study, we performed flux and spectral analysis of more than 3 year long (August 2008 to April 2012) Fermi-LAT data of the source. During this period, the source exhibits two different modes of flux variability with characteristic timescales of ~75 and ~140 days, respectively. We also notice that the flux variations are characterized by a weak spectral hardening. The GeV spectrum of the source shows a clear deviation from a simple power law, and is better explained by a broken power law. Similar to other bright Fermi blazars, the break energy does not vary with the source flux during the different activity states. We discuss several possible scenarios to explain the observed spectral break.

  14. The 6 GeV TMD Program at Jefferson Lab

    SciTech Connect (OSTI)

    Puckett, Andrew J. [University of Connecticut, JLAB

    2015-01-01T23:59:59.000Z

    The study of the transverse momentum dependent parton distributions (TMDs) of the nucleon in semi-inclusive deep-inelastic scattering (SIDIS) has emerged as one of the major physics motivations driving the experimental program using the upgraded 11 GeV electron beam at Jefferson Lab’s Continuous Electron Beam Accelerator Facility (CEBAF). The accelerator construction phase of the CEBAF upgrade is essentially complete and commissioning of the accelerator has begun as of April, 2014. As the new era of CEBAF operations begins, it is appropriate to review the body of published and forthcoming results on TMDs from the 6 GeV era of CEBAF operations, discuss what has been learned, and discuss the key challenges and opportunities for the 11 GeV SIDIS program of CEBAF.

  15. Spin Structure with JLab 6 and 12 GeV

    SciTech Connect (OSTI)

    Jian-Ping Chen

    2012-02-01T23:59:59.000Z

    Highlights of JLab 6 GeV results on spin structure study and plan for 12 GeV program. Spin structure study is full of surprises and puzzles. A decade of experiments from JLab yield these exciting results: (1) valence spin structure; (2) precision measurements of g{sub 2}/d{sub 2} - high-twist; (3) spin sum rules and polarizabilities; and (4) first neutron transversity. There is a bright future as the 12 GeV Upgrade will greatly enhance our capability: (1) Precision determination of the valence quark spin structure flavor separation; (2) Precision measurements of g{sub 2}/d{sub 2}; and (3) Precision extraction of transversity/tensor charge.

  16. Reducing 68Ge Background in Dark Matter Experiments

    SciTech Connect (OSTI)

    Kouzes, Richard T.; Orrell, John L.

    2011-03-01T23:59:59.000Z

    Experimental searches for dark matter include experiments with sub-0.5 keV-energy threshold high purity germanium detectors. Experimental efforts, in partnership with the CoGeNT Collaboration operating at the Soudan Underground Laboratory, are focusing on energy threshold reduction via noise abatement, reduction of backgrounds from cosmic ray generated isotopes, and ubiquitous environmental radioactive sources. The most significant cosmic ray produced radionuclide is 68Ge. This paper evaluates reducing this background by freshly mining and processing germanium ore. The most probable outcome is a reduction of the background by a factor of two, and at most a factor of four. A very cost effective alternative is to obtain processed Ge as soon as possible and store it underground for 18 months.

  17. Effect of mixed Ge/Si cross-linking on the physical properties of amorphous Ge-Si-Te networks

    SciTech Connect (OSTI)

    Gunasekera, K.; Boolchand, P. [School of Electronics and Computing Systems, College of Engineering and Applied Science, University of Cincinnati, Cincinnati, Ohio 45221-0030 (United States); Micoulaut, M., E-mail: mmi@lptl.jussieu.fr [Laboratoire de Physique Théorique de la Matière Condensée, Université Pierre et Marie Curie, 4 Place Jussieu, F-75252 Paris Cedex 05 (France)

    2014-04-28T23:59:59.000Z

    Amorphous Ge{sub x}Si{sub x}Te{sub 1?2x} glasses are studied as a function of composition by a combination of experimental and theoretical methods, allowing for a full description of the network structure in relationship with physico-chemical properties. Calorimetric and thermal measurements reveal that such glasses display an anomalous behavior across a range of compositions x{sub c1}=7.5% and Ge, Si) are increased. The structural manifestation of these anomalies is understood from ?{sup 119}Sn Mössbauer spectroscopy and First Principles Molecular Dynamics at selected compositions (Ge{sub 20}Te{sub 80}, Si{sub 20}Te{sub 80}, and Ge{sub 10}Si{sub 10}Te{sub 80}). The numerical models reveal the quite different roles played by the modifier or network cross-linker Ge or Si atoms, Si being more tetrahedral in sp{sup 3} geometry, whereas Mössbauer spectroscopy shows that the nature of chemical bonding is dramatically changed around x??8%. The precise evolution of the local structure and chemical bonding ultimately allows understanding the origin of the intermediate phase in these complex tellurides.

  18. Reflection high-energy electron diffraction evaluation of thermal deoxidation of chemically cleaned Si, SiGe, and Ge layers for solid-source molecular beam epitaxy

    SciTech Connect (OSTI)

    Ali, Dyan; Richardson, Christopher J. K. [Laboratory for Physical Sciences, University of Maryland, College Park, Maryland 20740 (United States)

    2012-11-15T23:59:59.000Z

    The authors present a study on the thermal evolution of the reflection high-energy electron diffraction pattern of chemically cleaned (001)-oriented Si, Ge, and SiGe surfaces, associating observed changes in the reconstructions with the desorption of known residual contaminants for Si and Ge surfaces. The implications of residual oxides prior to epitaxy on stacking fault densities in the grown films are presented. Further evidence for the two-phase nature of oxides on SiGe surfaces is provided, demonstrating that it is necessary to heat a SiGe surface up to the thermal deoxidation temperature of a Si surface to obtain stacking fault-free growth.

  19. C incorporation in epitaxial Ge1yCy layers grown on Ge,,001...: An ab initio study D. Gall, J. D'Arcy-Gall, and J. E. Greene

    E-Print Network [OSTI]

    Gall, Daniel

    C incorporation in epitaxial Ge1ÀyCy layers grown on Ge,,001...: An ab initio study D. Gall, J. D lattice site configurations in fully coherent Ge1 yCy layers grown on Ge 001 . Calculations using strained configuration involving only one C atom per configura- tion. The bond-centered interstitial and the Ge-C split

  20. EBIC characterization of strained Si/SiGe heterostructures

    SciTech Connect (OSTI)

    Yakimov, E. B. [Russian Academy of Sciences, Institute of Microelectronics Technology and High-Purity Materials (Russian Federation)], E-mail: yakimov@ipmt-hpm.ac.ru; Zhang, R. H.; Rozgonyi, G. A. [North Carolina State University, Department of Materials Science and Engineering (United States); Seacrist, M. [MEMC Electronic Materials (United States)

    2007-04-15T23:59:59.000Z

    Strained-Si/SiGe heterostructure is studied by EBIC. The effect of annealing at 800 deg. C is investigated. The EBIC images obtained at different beam energies are analyzed. The analysis of images obtained shows that misfit dislocation bunches in the graded SiGe layer could not explain the cross-hatch contrast dependence on E{sub b}. Therefore, at least a part of this contrast should be associated with other defects located closer to the depletion region. It is assumed that dislocation trails could play the role of such defects.

  1. Double-sided Tl{sub 2}Ba{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10} thin films based high temperature superconducting filter operating above 100?K

    SciTech Connect (OSTI)

    Xie, Wei; Wang, Pei; He, Ming, E-mail: heming@nankai.edu.cn; Qiao, Ren; Du, Jia-Nan; Gao, Xiao-Xin; Liu, Xin; Zhang, Xu; Ji, Lu; Chen, Hai-Hua; Zhao, Xin-Jie, E-mail: zhaoxj@nankai.edu.cn [College of Electronic Information and Optical Engineering, Nankai University, Tianjin 300071 (China)

    2014-09-01T23:59:59.000Z

    A high temperature superconducting (HTS) filter on double-sided Tl{sub 2}Ba{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10} (Tl-2223) thin films is designed in this letter. High-quality double-sided Tl-2223 thin films are prepared on 10?×?10?×?0.5?mm{sup 3} LaAlO{sub 3} (001) substrate. The critical temperatures T{sub c} of the films are 120?±?1?K and the critical current densities J{sub c} are 3–4 MA/cm{sup 2} at 77?K for both sides. X-ray diffraction ?-2? scans and rotational ?-scans prove that the films are strongly textured with the c axis perpendicular to the substrate surface. A 3-pole band-pass filter is then fabricated on the Tl-2223 thin films with 4% relative bandwidth and a center frequency of 4.0 GHz. At 77?K, 100?K, and 102?K, the insertion loss in the passband is 0.088?dB, 0.21?dB, and 0.27?dB, respectively. These performances show that the proposed HTS filter is satisfying even when the operating temperature is above 100?K, which makes it possible to work in outer space without cryogenic systems.

  2. TL1A induces the expression of TGF-b-inducible gene h3 (big-h3) through PKC, PI3K, and ERK in THP-1 cells

    E-Print Network [OSTI]

    Lee, Won-Ha

    TL1A induces the expression of TGF-b-inducible gene h3 (big-h3) through PKC, PI3K, and ERK in THP-1 of protein kinase C (PKC), extracellular signal-regulated kinase (ERK), phosphoinositide kinase-3 (PI3K blocked the phos- phorylation of AKT without affecting ERK phosphorylation. On the other hand, suppression

  3. Direct band gap optical emission from Ge islands grown on relaxed Si{sub 0.5}Ge{sub 0.5}/Si (100) substrate

    SciTech Connect (OSTI)

    Aluguri, R.; Manna, S.; Ray, S. K., E-mail: physkr@phy.iitkgp.ernet.in [Department of Physics and Meteorology, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India)

    2014-01-07T23:59:59.000Z

    Strained Ge islands have been grown on fully relaxed Si{sub 0.5}Ge{sub 0.5} substrate by pulsed laser ablation technique. The formation of strained Ge islands has been found for film with higher thickness following Stranski–Krastanov growth mechanism. The variation of strain with changing Ge layer thickness has been analyzed using Raman spectroscopy and high-resolution X-ray diffraction techniques. X-ray photoelectron spectra have shown the absence of any Si-Ge intermixing and oxidation of Ge films. A strong no-phonon photoluminescence emission from Ge islands has been observed, showing the superior optical characteristics of the islands grown on relaxed substrate.

  4. TL and PL studies on cubic fluoroperovskite single crystal (KMgF{sub 3}: Eu{sup 2+}, Ce{sup 3+})

    SciTech Connect (OSTI)

    Daniel, D. Joseph, E-mail: josephd@ssn.edu.in; Ramasamy, P. [Centre for Crystal Growth, SSN College of Engineering, Kalavakkam, Tamilnadu-603110 (India); Madhusoodanan, U.; Annalakshmi, O. [Radiological Safety Division, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamilnadu - 603102 (India)

    2014-04-24T23:59:59.000Z

    The perovskite-like KMgF{sub 3} polycrystalline compounds were synthesized by standard solid state reaction technique. Phase purity of the synthesized compounds was analyzed by powder X-ray diffraction technique. Single crystals of (0.2 mol% of EuF{sub 3} and CeF{sub 3}) Co-doped KMgF{sub 3} have been grown from melt by using a vertical Bridgman-Stockbarger method. Thermoluminescence (TL) characteristics of KMgF{sub 3} samples doped with Eu{sub 2+} and Ce{sub 3+} have been studied after ?-ray irradiation. At ambient conditions the photoluminescence spectra consisted of sharp line peaked of Eu{sub 2+} at 360 nm attributed to the f ? f transition ({sup 6}P{sub 7/2}?{sup 8}S{sub 7/2}) could only be observed due to the energy transfer from Ce{sub 3+} to Eu{sub 2+}.

  5. INFLUENCE OF SUBSTRATE OFF-CUT ON THE DEFECT STRUCTURE IN RELAXED GRADED Si-Ge/Si LAYERS

    E-Print Network [OSTI]

    INFLUENCE OF SUBSTRATE OFF-CUT ON THE DEFECT STRUCTURE IN RELAXED GRADED Si-Ge/Si LAYERS SRIKANTH B and Engineering, University of California, Los Angeles, CA 90095. ABSTRACT Relaxed graded Si-Ge/Si layers can of these applications requires a different final Ge concentration in the graded Si-Ge layer. With increasing Ge content

  6. GE & AE Extension Request Form, Version 11, Feb 2013, JC Program Change General English or Academic English

    E-Print Network [OSTI]

    Escher, Christine

    GE & AE Extension Request Form, Version 11, Feb 2013, JC Program Change ­ General English of GE do you wish to request? 1 2 3 4 (GE sessions are 5 weeks) How many GE hours do you wish to take ______________________________________________ Date _________________ #12;GE & AE Extension Request Form, Version 11, Feb 2013, JC Please submit

  7. Time-resolved photoluminescence from self-assembled Ge(Si) islands in multilayer SiGe/Si and SiGe/SOI structures

    SciTech Connect (OSTI)

    Yablonskiy, A. N., E-mail: yablonsk@ipm.sci-nnov.ru; Baidakova, N. A. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation)] [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation); Novikov, A. V. [Lobachevskyi University of Nizhni Novgorod, Physical-Technical Research Institute (Russian Federation)] [Lobachevskyi University of Nizhni Novgorod, Physical-Technical Research Institute (Russian Federation); Lobanov, D. N. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation)] [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation)

    2013-11-15T23:59:59.000Z

    The results of a study of the spectral and temporal characteristics of the photoluminescence (PL) from multilayer structures with self-assembled Ge(Si) islands grown on silicon and 'silicon-on-insulator' substrates in relation to temperature and the excitation-light wavelength are presented. A substantial increase in island-related PL intensity is observed for structures with Ge(Si) islands grown on silicon substrates upon an increase in temperature from 4 to 70 K. This increase is due to the diffusion of nonequilibrium carriers from the silicon substrate into the active layer with the islands. In this case, a slow component with a characteristic time of {approx}100 ns appears in the PL rise kinetics. At the same time, no slow component in the PL rise kinetics and no rise in the PL intensity with increasing temperature are observed for structures grown on 'silicon-on-insulator' substrates, in which the active layer with the islands is insulated from the silicon substrate. It is found that absorption of the excitation light in the islands and SiGe wetting layers mainly contributes to the excitation of the PL signal from the islands under sub-bandgap optical pump conditions.

  8. Gigantic uphill diffusion during self-assembled growth of Ge quantum dots on strained SiGe sublayers

    SciTech Connect (OSTI)

    Valakh, M. Ya.; Lytvyn, P. M.; Nikolenko, A. S.; Strelchuk, V. V. [V. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine, pr. Nauki 45, 03680 Kyiv (Ukraine); Krasilnik, Z. F.; Lobanov, D. N.; Novikov, A. V. [Institute for Physics of Microstructures, RAS, GSP-105, Nizhny Novgorod 603950 (Russian Federation)

    2010-04-05T23:59:59.000Z

    Raman spectroscopy and atomic-force microscopy were applied to study the morphology of nanoislands grown on strained Si{sub 1-x}Ge{sub x} sublayers. It was shown that the growth of nanoislands on strained Si{sub 1-x}Ge{sub x} sublayer not only induces the effect of their spatial ordering but also enhances the role of interdiffusion processes. Unusual high island volume increase during the epitaxy is explained by anomalous strong material diffusion from the sublayer into the islands, induced by nonuniform field of elastic strains.

  9. Inhibitive formation of nanocavities by introduction of Si atoms in Ge nanocrystals produced by ion implantation

    SciTech Connect (OSTI)

    Cai, R. S.; Shang, L.; Liu, X. H.; Zhang, Y. J. [The Cultivation Base for State Key Laboratory, Qingdao University, No. 308 Ningxia Road, Qingdao 266071 (China); Wang, Y. Q., E-mail: yqwang@qdu.edu.cn, E-mail: barba@emt.inrs.ca [The Cultivation Base for State Key Laboratory, Qingdao University, No. 308 Ningxia Road, Qingdao 266071 (China); College of Physics Science, Qingdao University, No. 308 Ningxia Road, Qingdao 266071 (China); Ross, G. G.; Barba, D., E-mail: yqwang@qdu.edu.cn, E-mail: barba@emt.inrs.ca [INRS-Énergie, Matériaux et Télécommunications, 1650 boulevard Lionel-Boulet, Varennes Québec J3X 1S2 (Canada)

    2014-05-28T23:59:59.000Z

    Germanium nanocrystals (Ge-nc) were successfully synthesized by co-implantation of Si and Ge ions into a SiO{sub 2} film thermally grown on (100) Si substrate and fused silica (pure SiO{sub 2}), respectively, followed by subsequent annealing at 1150?°C for 1?h. Transmission electron microscopy (TEM) examinations show that nanocavities only exist in the fused silica sample but not in the SiO{sub 2} film on a Si substrate. From the analysis of the high-resolution TEM images and electron energy-loss spectroscopy spectra, it is revealed that the absence of nanocavities in the SiO{sub 2} film/Si substrate is attributed to the presence of Si atoms inside the formed Ge-nc. Because the energy of Si-Ge bonds (301?kJ·mol{sup ?1}) are greater than that of Ge-Ge bonds (264?kJ·mol{sup ?1}), the introduction of the Si-Ge bonds inside the Ge-nc can inhibit the diffusion of Ge from the Ge-nc during the annealing process. However, for the fused silica sample, no crystalline Si-Ge bonds are detected within the Ge-nc, where strong Ge outdiffusion effects produce a great number of nanocavities. Our results can shed light on the formation mechanism of nanocavities and provide a good way to avoid nanocavities during the process of ion implantation.

  10. 7-GeV Advanced Photon Source Conceptual Design Report

    SciTech Connect (OSTI)

    Not Available

    1987-04-01T23:59:59.000Z

    During the past decade, synchrotron radiation emitted by circulating electron beams has come into wide use as a powerful, versatile source of x-rays for probing the structure of matter and for studying various physical processes. Several synchrotron radiation facilities with different designs and characteristics are now in regular operation throughout the world, with recent additions in this country being the 0.8-GeV and 2.5-GeV rings of NSLS at Brookhaven National Laboratory. However, none of the operating facilities has been designed to use a low-emittance, high-energy stored beam, together with modern undulator devices, to produce a large number of hard x-ray beams of extremely high brilliance. This document is a proposal to the Department of Energy to construct and operate high-energy synchrotron radiation facility at Argonne National Laboratory. We have now chosen to set the design energy of this facility at 7.0 GeV, with the capability to operate at up to 7.5 GeV.

  11. Nucleon Form Factors experiments with 12 GeV CEBAF

    SciTech Connect (OSTI)

    Wojtsekhowski, Bogdan

    2008-11-01T23:59:59.000Z

    A number of precision form factor experiments at high momentum transfer will be performed with the 11 GeV electron beam of CEBAF. We review the approved proposals and the conceptual schemes of several new suggestions. Form factor data will serve as a major input for the construction of a tomographic image of the nucleon.

  12. GeV C. W. electron microtron design report

    SciTech Connect (OSTI)

    Not Available

    1982-05-01T23:59:59.000Z

    Rising interest in the nuclear physics community in a GeV C.W. electron accelerator reflects the growing importance of high-resolution short-range nuclear physics to future advances in the field. In this report major current problems are reviewed and the details of prospective measurements which could be made with a GeV C.W. electron facility are discussed, together with their impact on an understanding of nuclear forces and the structure of nuclear matter. The microtron accelerator has been chosen as the technology to generate the electron beams required for the research discussed because of the advantages of superior beam quality, low capital and operating cost and capability of furnishing beams of several energies and intensities simultaneously. A complete technical description of the conceptual design for a 2 GeV double-sided C.W. electron microtron is presented. The accelerator can furnish three beams with independently controlled energy and intensity. The maximum current per beam is 100 ..mu..amps. Although the precise objective for maximum beam energy is still a subject of debate, the design developed in this study provides the base technology for microtron accelerators at higher energies (2 to 6 GeV) using multi-sided geometries.

  13. Structural Changes in Vitreous GeSe4 under Pressure

    SciTech Connect (OSTI)

    Skinner L. B.; Parise J.; Benmore, C.J,; Antao, S.; Soignard, E.; Amin, S.A.; Bychkov, E.; Rissi, E. and Yarger, J.L.

    2011-11-21T23:59:59.000Z

    High-energy X-ray diffraction experiments have been performed on GeSe{sub 4} glass up to pressures of 8.6 GPa, and the equation of state has been measured up to 10 GPa. The X-ray structure factors reveal a decrease in the first sharp diffraction peak intensity and broadening with pressure, which signifies a break-up of the intermediate range order in the glass. In contrast, the principal peak in the structure factor shows an increase in intensity and a sharpening with pressure, which is attributed to an increase in extended range order and coherence of the compacted units. The average nearest neighbor coordination number is found to remain constant in GeSe{sub 4} glass (within experimental error) over the pressure range measured. This is in contrast with the gradual increase found in GeSe{sub 2} glass. Rather, in GeSe{sub 4} glass the densification mechanism is shown to be associated with large inward shifts of the second neighbor and higher coordination shells. These features appear as additional correlations at 3.3 and 5.3 {angstrom} in the differences taken between adjacent pair distribution functions with increasing pressure.

  14. The JLAB 12 GeV Energy Upgrade of CEBAF

    SciTech Connect (OSTI)

    Harwood, Leigh H. [JLAB

    2013-12-01T23:59:59.000Z

    This presentation should describe the progress of the 12GeV Upgrade of CEBAF at Jefferson Lab. The status of the upgrade should be presented as well as details on the construction, procurement, installation and commissioning of the magnet and SRF components of the upgrade.

  15. Demand Response Performance of GE Hybrid Heat Pump Water Heater

    SciTech Connect (OSTI)

    Widder, Sarah H.; Parker, Graham B.; Petersen, Joseph M.; Baechler, Michael C.

    2013-07-01T23:59:59.000Z

    This report describes a project to evaluate and document the DR performance of HPWH as compared to ERWH for two primary types of DR events: peak curtailments and balancing reserves. The experiments were conducted with GE second-generation “Brillion”-enabled GeoSpring hybrid water heaters in the PNNL Lab Homes, with one GE GeoSpring water heater operating in “Standard” electric resistance mode to represent the baseline and one GE GeoSpring water heater operating in “Heat Pump” mode to provide the comparison to heat pump-only demand response. It is expected that “Hybrid” DR performance, which would engage both the heat pump and electric elements, could be interpolated from these two experimental extremes. Signals were sent simultaneously to the two water heaters in the side-by-side PNNL Lab Homes under highly controlled, simulated occupancy conditions. This report presents the results of the evaluation, which documents the demand-response capability of the GE GeoSpring HPWH for peak load reduction and regulation services. The sections describe the experimental protocol and test apparatus used to collect data, present the baselining procedure, discuss the results of the simulated DR events for the HPWH and ERWH, and synthesize key conclusions based on the collected data.

  16. Demonstration of 2nd Generation Ducted GE "Brillion" Hybrid Water

    E-Print Network [OSTI]

    sharing partners. #12;Project Synopsis Evaluate the performance and demand response (DR) of the Gen II GE/frequency response) in the PNW and nationwide (Lu et al, 2011; Diao et al 2012) The demand response characteristics Participants Project Sponsors: DOE Building America Program/Bonneville Power Administration Contractor: PNNL

  17. Extraction of large valence-band energy offsets and comparison to theoretical values for strained-Si/strained-Ge type-II heterostructures on relaxed SiGe substrates

    E-Print Network [OSTI]

    Teherani, James T.

    Metal-oxide-semiconductor capacitors were fabricated on type-II staggered gap strained-Si/strained-Ge heterostructures epitaxially grown on relaxed SiGe substrates of various Ge fractions. Quasistatic quantum-mechanical ...

  18. Ge{sub 1-y}Sn{sub y} (y = 0.01-0.10) alloys on Ge-buffered Si: Synthesis, microstructure, and optical properties

    SciTech Connect (OSTI)

    Senaratne, C. L.; Kouvetakis, J. [Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287-1604 (United States); Gallagher, J. D.; Jiang, Liying; Smith, D. J.; Menéndez, J. [Department of Physics, Arizona State University, Tempe, Arizona 85287-1504 (United States); Aoki, Toshihiro [LeRoy Eyring Center for Solid State Science, Arizona State University, Tempe, Arizona 85287-1704 (United States)

    2014-10-07T23:59:59.000Z

    Novel hydride chemistries are employed to deposit light-emitting Ge{sub 1-y}Sn{sub y} alloys with y ? 0.1 by Ultra-High Vacuum Chemical Vapor Deposition (UHV-CVD) on Ge-buffered Si wafers. The properties of the resultant materials are systematically compared with similar alloys grown directly on Si wafers. The fundamental difference between the two systems is a fivefold (and higher) decrease in lattice mismatch between film and virtual substrate, allowing direct integration of bulk-like crystals with planar surfaces and relatively low dislocation densities. For y ? 0.06, the CVD precursors used were digermane Ge?H? and deuterated stannane SnD?. For y ? 0.06, the Ge precursor was changed to trigermane Ge?H?, whose higher reactivity enabled the fabrication of supersaturated samples with the target film parameters. In all cases, the Ge wafers were produced using tetragermane Ge?H?? as the Ge source. The photoluminescence intensity from Ge{sub 1–y}Sn{sub y}/Ge films is expected to increase relative to Ge{sub 1–y}Sn{sub y}/Si due to the less defected interface with the virtual substrate. However, while Ge{sub 1–y}Sn{sub y}/Si films are largely relaxed, a significant amount of compressive strain may be present in the Ge{sub 1–y}Sn{sub y}/Ge case. This compressive strain can reduce the emission intensity by increasing the separation between the direct and indirect edges. In this context, it is shown here that the proposed CVD approach to Ge{sub 1–y}Sn{sub y}/Ge makes it possible to approach film thicknesses of about 1 ?m, for which the strain is mostly relaxed and the photoluminescence intensity increases by one order of magnitude relative to Ge{sub 1–y}Sn{sub y}/Si films. The observed strain relaxation is shown to be consistent with predictions from strain-relaxation models first developed for the Si{sub 1–x}Ge{sub x}/Si system. The defect structure and atomic distributions in the films are studied in detail using advanced electron-microscopy techniques, including aberration corrected STEM imaging and EELS mapping of the average diamond–cubic lattice.

  19. Near-Infrared Photoluminescence Enhancement in Ge/CdS and Ge/ZnS Core/Shell Nanocrystals: Utilizing IV/II-VI Semiconductor Epitaxy

    SciTech Connect (OSTI)

    Guo, Yijun [Ames Laboratory; Rowland, Clare E [Argonne National Laboratory; Schaller, Richard D [Argonne National Laboratory; Vela, Javier [Ames Laboratory

    2014-08-26T23:59:59.000Z

    Ge nanocrystals have a large Bohr radius and a small, size-tunable band gap that may engender direct character via strain or doping. Colloidal Ge nanocrystals are particularly interesting in the development of near-infrared materials for applications in bioimaging, telecommunications and energy conversion. Epitaxial growth of a passivating shell is a common strategy employed in the synthesis of highly luminescent II–VI, III–V and IV–VI semiconductor quantum dots. Here, we use relatively unexplored IV/II–VI epitaxy as a way to enhance the photoluminescence and improve the optical stability of colloidal Ge nanocrystals. Selected on the basis of their relatively small lattice mismatch compared with crystalline Ge, we explore the growth of epitaxial CdS and ZnS shells using the successive ion layer adsorption and reaction method. Powder X-ray diffraction and electron microscopy techniques, including energy dispersive X-ray spectroscopy and selected area electron diffraction, clearly show the controllable growth of as many as 20 epitaxial monolayers of CdS atop Ge cores. In contrast, Ge etching and/or replacement by ZnS result in relatively small Ge/ZnS nanocrystals. The presence of an epitaxial II–VI shell greatly enhances the near-infrared photoluminescence and improves the photoluminescence stability of Ge. Ge/II–VI nanocrystals are reproducibly 1–3 orders of magnitude brighter than the brightest Ge cores. Ge/4.9CdS core/shells show the highest photoluminescence quantum yield and longest radiative recombination lifetime. Thiol ligand exchange easily results in near-infrared active, water-soluble Ge/II–VI nanocrystals. We expect this synthetic IV/II–VI epitaxial approach will lead to further studies into the optoelectronic behavior and practical applications of Si and Ge-based nanomaterials.

  20. The polygallides: Yb{sub 3}Ga{sub 7}Ge{sub 3} and YbGa{sub 4}Ge{sub2}.

    SciTech Connect (OSTI)

    Peter, S. C.; Malliakas, C. D.; Nakotte, H.; Kothapilli, K.; Rayaprol, S.; Schultz, A. J.; Kanatzidis, M. G. (Materials Science Division); ( XSD); (Northwestern Univ.); (Jawaharlal Nehru Centre for Adv. Sci. Res.); (New Mexico State Univ.); (Los Alamos Nat. Lab.); (UGC-DAE Consortium for Sci. Res.)

    2012-03-01T23:59:59.000Z

    Yb{sub 3}Ga{sub 7}Ge{sub 3} and YbGa{sub 4}Ge{sub 2} were obtained from reactions of Yb and Ge in excess liquid gallium. The crystal structure of Yb{sub 3}Ga{sub 7}Ge{sub 3} was refined using X-ray and neutron diffraction data on selected single crystals. Yb{sub 3}Ga{sub 7}Ge{sub 3} crystallizes in the monoclinic space group C2/c with lattice constants a = 12.2261(20) {angstrom}, b = 10.7447(20) {angstrom}, c = 8.4754(17) {angstrom} and {beta} = 110.288(30){sup o} (neutron diffraction data). The crystal structure of Yb{sub 3}Ga{sub 7}Ge{sub 3} is an intergrowth of planar layers of YbGa{sub x}Ge{sub y} and puckered layers of (Ge)n. YbGa{sub 4}Ge{sub 2} crystallizes in a modified PuGa{sub 6} structure type in the tetragonal polar space group I4cm with lattice constants a = b = 5.9874(6) {angstrom} and c = 15.1178(19) {angstrom}. The structure of YbGa{sub 4}Ge{sub 2} is an intergrowth of puckered Ga layers and puckered Ga{sub x}Ge{sub y} layers with Yb atoms residing within the channels formed by the connection of the two layers. Physical properties, resistivity ({rho}), magnetic susceptibility ({chi}) and specific heat (C) were measured for Yb{sub 3}Ga{sub 7}Ge{sub 3}. No magnetic ordering was observed. It was found that at low temperatures, {rho} varied as T{sup 2} and C{alpha}T, indicating Fermi-liquid regime in Yb{sub 3}Ga{sub 7}Ge{sub 3} at low temperatures.

  1. Adsorption of alkali metals on Ge(001)(2×1) surface. |...

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

    alkali metals on Ge(001)(2×1) surface. Adsorption of alkali metals on Ge(001)(2×1) surface. Abstract: Ab initio total energy calculations have been performed for Na, K...

  2. Large inherent optical gain from the direct gap transition of Ge thin films

    E-Print Network [OSTI]

    Wang, Xiaoxin

    The recent demonstration of Ge-on-Si diode lasers renews the interest in the unique carrier dynamics of Ge involving both direct (?) and indirect (L) valleys. Here, we report a large inherent direct gap optical gain ...

  3. Epitaxial Ge/Il-V Heterostructures : MOCVD growth, characterization, and applications

    E-Print Network [OSTI]

    Bai, Yu, Ph.D. Massachusetts Institute of Technology

    2011-01-01T23:59:59.000Z

    Epitaxial Ge thin films are being investigated for many important roles in next generation microelectronics. Metal-oxide-semiconductor field effect transistors (MOSFETs) utilizing Ge channels have demonstrated dramatic ...

  4. GE Hydro Asia Co Ltd formerly Kvaerner Power Equipment Co Ltd...

    Open Energy Info (EERE)

    GE Hydro Asia Co Ltd formerly Kvaerner Power Equipment Co Ltd Kvaerner Hangfa Jump to: navigation, search Name: GE Hydro Asia Co Ltd (formerly Kvaerner Power Equipment Co., Ltd...

  5. Ferromagnetism in Mn-Implanted Epitaxially Grown Ge on Si(100)

    E-Print Network [OSTI]

    Guchhait, S.

    2011-01-01T23:59:59.000Z

    group-IV-based dilute magnetic semiconductors by electronicMn x Ge 1-x dilute magnetic semiconductor”, Applied Physicsamorphous Ge 1-x Mn x magnetic semiconductor films”, Journal

  6. EA-0389: Proposed 7-GeV Advanced Photon Source, Argonne, Illinois

    Broader source: Energy.gov [DOE]

    This EA evaluates the environmental impacts of a proposal for construction and operation of a 6- to 7-GeV synchrotron radiation source known as the 7-GeV Advanced Photon Source at DOE's Argonne...

  7. 6 GeV LIGHT SOURCE PROJECT COST ESTIMATING PROCEDURE LS-34

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

    GeV LIGHT SOURCE PROJECT COST ESTIMATING PROCEDURE LS-34 October 23, 1985 YCAVR To maintain uniformity in estimating the cost requirements of the various components of the 6 GeV...

  8. $J/?$, $?(2S)$ Production in pp Collisions at E=510 GeV

    E-Print Network [OSTI]

    Leonard S. Kisslinger; Debasish Das

    2014-10-06T23:59:59.000Z

    This brief report is an extension of studies of $J/\\Psi,\\Psi(2S)$ production in pp collisions at the BNL with E=$\\sqrt{s}$=200 GeV to E=510 GeV at PHENIX.

  9. Postdoctoral Positions: Si/SiGe Quantum Dots and Quantum Computing Eriksson Group

    E-Print Network [OSTI]

    Saffman, Mark

    Postdoctoral Positions: Si/SiGe Quantum Dots and Quantum Computing Eriksson Group Department in the area of Si/SiGe quantum dots and quantum computing. Recent advances in our group include single

  10. Temperature dependent metal-induced lateral crystallization of amorphous SiGe on insulating substrate

    SciTech Connect (OSTI)

    Kanno, Hiroshi; Toko, Kaoru; Sadoh, Taizoh; Miyao, Masanobu [Department of Electronics, Kyushu University, 744 Motooka, Fukuoka 819-0395 (Japan)

    2006-10-30T23:59:59.000Z

    Metal-induced lateral crystallization (MILC) of amorphous SiGe films on SiO{sub 2} has been investigated as a function of Ge fraction (0%-100%) and annealing temperature (320-550 deg. C). High temperature annealing (>500 deg. C) caused spontaneous nucleation in amorphous SiGe with a high Ge fraction (>70%). This suppressed the progress of MILC. Spontaneous nucleation was significantly suppressed by lowering the annealing temperature (<400 deg. C). As a result, large poly-SiGe regions (>20 {mu}m) were observed around Ni patterns even for high Ge fractions (>70%). In this way, MILC of amorphous SiGe was achieved for samples with whole Ge fractions (0%-100%)

  11. Commercialization potential of compositionally graded Ge - Si??x?Gex? - Si substrates for solar applications

    E-Print Network [OSTI]

    Goh, Johnathan Jian Ming

    2006-01-01T23:59:59.000Z

    This project considers the potential of Ge - Si??x?Gex? - Si substrates for solar applications. The use of compositionally graded substrates to achieve heterointegration across different materials platforms such as Si, Ge ...

  12. Electron Backscatter Diffraction of a Ge Growth Tip from a Vertical...

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

    of a Ge Growth Tip from a Vertical Gradient Freeze Furnace. Electron Backscatter Diffraction of a Ge Growth Tip from a Vertical Gradient Freeze Furnace. Abstract: The growth-tip...

  13. LIFETIME AND RADIATIVE EFFICIENCY VS DENSITY IN THE STRAIN-CONFINED ELECTRON-HOLE LIQUID IN Ge

    E-Print Network [OSTI]

    Kelso, Susan M.

    2011-01-01T23:59:59.000Z

    electron-hole liquid (SCEHL) in Ge. Sample CR50 was T = 1.9CONFINED ELECTRON-HOLE LIQUID IN Ge Susan M. Kelso and JohnCONFINED ELECTRON-HOLE LIQUID IN Ge Susan M. Kelso and John

  14. SiGe HBT linear-in-dB high dynamic range RF envelope detectors and wideband high linearity amplifiers

    E-Print Network [OSTI]

    Pan, Hsuan-yu

    2010-01-01T23:59:59.000Z

    1.1 SiGe BiCMOS Technology . . . . . . .A Linear-in-dB SiGe HBT Wideband High Dynamic Range RFpower dissapation trade-off between Si BJTs and SiGe HBTs [

  15. Ris-M-2737 ' / > ^ ' ' . / , / -THE PHASES OF Pb/Ge(lll)

    E-Print Network [OSTI]

    #12;Risø-M-2737 ' / > ^ ' ' . / , / - THE PHASES OF Pb/Ge(lll): A SURFACE X-RAY DIFFRACTION STUDY of a chemisorbed overlayer of Pb on the Ge(lll) surface. Three phases of Pb/Ge(lll) exist in the monolayer regime: the a- and B-phases with a V3xV3R30° unit cell, and a high-temperature IX1 phase. In the 1X1 phase of Pb/Ge

  16. Directional correlation of [gamma] transitions in [sup 72]Ge following the decay of [sup 72]Ga

    SciTech Connect (OSTI)

    Landulfo, E.; Saxena, R.N.; Zamboni, C.B.; Lapolli, A.L. (Instituto de Pesquisas Energeticas e Nucleares, IPEN-Comissao Nacional de Energia Nuclear de Brasil, Sao Paulo, Sao Paulo (Brazil))

    1994-08-01T23:59:59.000Z

    Directional correlations of coincident gamma transitions in [sup 72]Ge have been measured following the [beta][sup [minus

  17. MECHANICS OF RELAXING SiGe ISLANDS ON A VISCOUS GLASS , J. Liang1

    E-Print Network [OSTI]

    Suo, Zhigang

    MECHANICS OF RELAXING SiGe ISLANDS ON A VISCOUS GLASS R. Huang1 , H. Yin2 , J. Liang1 , J.C. Sturm2, a SiGe thin film, a glass layer, and a Si wafer. The SiGe film is a perfect crystal, and is under biaxial compression. Pattern the SiGe film into islands. On annealing, the glass flows and the islands

  18. Why is GeV physics relevant in the age of the LHC?

    SciTech Connect (OSTI)

    Pennington, Michael R. [JLAB

    2014-02-01T23:59:59.000Z

    The contribution that Jefferson Lab has made, with its 6 GeV electron beam, and will make, with its 12 GeV upgrade, to our understanding of the way the fundamental interactions work, particularly strong coupling QCD, is outlined. The physics at the GeV scale is essential even in TeV collisions.

  19. 2D-GE IMAGE SEGMENTATION BASED ON LEVEL-SETS E.A. Mylona a

    E-Print Network [OSTI]

    Athens, University of

    2D-GE IMAGE SEGMENTATION BASED ON LEVEL-SETS E.A. Mylona a , M.A. Savelonas a , D. Maroulis a , M of protein spots in 2D-GE images. The proposed scheme incorporates a protein spot detection stage based both software packages in terms of segmentation performance. Index Terms--2D-GE Images, Protein Spot

  20. Surface Science Letters Self-assembled growth of ordered Ge nanoclusters on

    E-Print Network [OSTI]

    Gao, Hongjun

    Surface Science Letters Self-assembled growth of ordered Ge nanoclusters on the Si(1 1 1)-(7 Â 7-assembled growth of submonolayer Ge on the Si(1 1 1)-(7 Â 7) surface grown by solid phase epitaxy has been studied using scanning tunneling microscopy. Ordered Ge nanoclusters on the surface are formed by the deposition

  1. Distinct local electronic structure and magnetism for Mn in amorphous Si and Ge

    E-Print Network [OSTI]

    Zeng, Li

    2010-01-01T23:59:59.000Z

    Mn-Si (red squares) and Mn-Ge distances (blue circles) d asof the number of Si or Ge nearest neighbours N c ; (c) localthree Mn atoms with different N c in a-Mn 0.094 Ge 0.906 .

  2. Black Ge Based on Crystalline/Amorphous Core/Shell Nanoneedle Arrays

    E-Print Network [OSTI]

    Javey, Ali

    Black Ge Based on Crystalline/Amorphous Core/Shell Nanoneedle Arrays Yu-Lun Chueh,,§,|,# Zhiyong, ROC ABSTRACT Direct growth of black Ge on low-temperature substrates, including plastics and rubber is reported. The material is based on highly dense, crystalline/amorphous core/shell Ge nanoneedle arrays

  3. Defects in Ge and Si caused by 1 MeV Si+ implantation*

    E-Print Network [OSTI]

    Florida, University of

    Defects in Ge and Si caused by 1 MeV Si+ implantation* D. P. Hickeya Department of Materials defect formation and evolution in the 001 Ge and Si wafers implanted with 1 MeV Si+ and 40 keV Si dissolve at the projected range for nonamorphizing implants into Si. However, in Ge, no 311 defect

  4. Formation of Ge nanoclusters on Si(1 1 1)-7 7 surface at high temperature

    E-Print Network [OSTI]

    Gao, Hongjun

    Formation of Ge nanoclusters on Si(1 1 1)-7 · 7 surface at high temperature H.M. Guo, Y.L. Wang, H for publication 17 May 2004 Available online 5 June 2004 Abstract We report on Ge nanocluster formation on Si(1 1 of the Ge clusters are more uniform than those obtained at room temperature due to an increase

  5. Transistor-Based Ge/SOI Photodetector for Integrated Silicon Photonics

    E-Print Network [OSTI]

    Luo, Xi

    2011-01-01T23:59:59.000Z

    11. Y. -H. Kuo, Y. -K. Lee, Y. Ge, S. Ren, J. E. Roth, T. I.Colace and G. Assanto, “Poly-Ge Near-infrared PhotodetectorsMasini and G. Assanto, “Ge on Si p-i-n photodiodes operating

  6. Alloyed junction Ge Esaki diodes on Si substrates realised by aspect ratio trapping

    E-Print Network [OSTI]

    Rommel, Sean

    Alloyed junction Ge Esaki diodes on Si substrates realised by aspect ratio trapping technique D. Pawlik, S. Sieg, S.K. Kurinec, S.L. Rommel, Z. Cheng, J.-S. Park, J. Hydrick and A. Lochtefeld A Ge Esaki diode is demonstrated on Si atop a coalesced epitaxial layer of Ge grown through narrow openings in SiO2

  7. Materials synthesis and investigation of itinerant ferromagnetism in the UCo?-xFex Ge system

    E-Print Network [OSTI]

    Huang, Kevin

    2009-01-01T23:59:59.000Z

    B. UCo 1?x Fe x Ge . . . . . . . . . . . . . 1. Polycrystalvs temperature data of UCo 1?x Fe x Ge from x = 0.0 to x =vs temperature data of UCo 1?x Fe x Ge from x = 0.20 to x =

  8. Ge incorporation inside 4H-SiC during Homoepitaxial growth by chemical vapor

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Ge incorporation inside 4H-SiC during Homoepitaxial growth by chemical vapor deposition. Kassem Ilmenau (Germany) Abstract. In this work, we report on the addition of GeH4 gas during homoepitaxial growth of 4H-SiC by chemical vapour deposition. Ge introduction does not affect dramatically the surface

  9. Room-temperature 1.3 pm electroluminescence from strained Si, -,Ge,/Si quantum wells

    E-Print Network [OSTI]

    Room-temperature 1.3 pm electroluminescence from strained Si, -,Ge,/Si quantum wells Q. Mi, X. Xiao report the first room-temperature 1.3 ,um electroluminescence from strained Sir-,Ge,/Si quantum wells to that from the Sit-,GeX wells. A minimum band offset is required to have effective room

  10. GE & AE Extension Request Form, Version 8, Feb 2013, JC Program Extension

    E-Print Network [OSTI]

    Escher, Christine

    GE & AE Extension Request Form, Version 8, Feb 2013, JC Program Extension General English English (GE) Academic English (AE) 2. Which term will this extension begin? Fall Winter Spring Summer 3 of General English do you wish to request? 1 2 3 4 5 6 (GE sessions are 5 weeks) How many General English

  11. Coexisting Superconductivity and Magnetism in UCoGe Gregory S. Boebinger, National High Magnetic Field Laboratory

    E-Print Network [OSTI]

    Weston, Ken

    Coexisting Superconductivity and Magnetism in UCoGe Gregory S. Boebinger, National High Magnetic focused on the coexistence of superconductivity and ferromagnetism, including UGe2, URhGe, and UCoGe. In these materials, superconductivity develops below the ferromagnetic Curie temperature TC without destroying

  12. Crack formation in GaAs heteroepitaxial films on Si and SiGe virtual substrates

    E-Print Network [OSTI]

    Crack formation in GaAs heteroepitaxial films on Si and SiGe virtual substrates V. K. Yang, MAs films grown on Si and SiGe virtual substrates analytically and experimentally. The analytical model­10 Relaxed SiGe graded layers on Si have produced the highest quality GaAs on Si to date for the integration

  13. \\Development, implementation and veri cation of a physics-based Si/SiGe

    E-Print Network [OSTI]

    Paper I \\Development, implementation and veri#12;cation of a physics-based Si/SiGe HBT model and verification of a physics­based Si/SiGe HBT model for millimeter­wave non­ linear circuit simulations. S. Bruce thermal dependence has been developed for Si/SiGe HBTs. The model takes into account several effects

  14. EVOLUTION OF SELF-INTERSTITIALS INDUCED BY ION-IMPLANTATION IN SiGe ALLOYS

    E-Print Network [OSTI]

    Florida, University of

    EVOLUTION OF SELF-INTERSTITIALS INDUCED BY ION-IMPLANTATION IN SiGe ALLOYS By ROBERT T. CROSBY and Astronomy at the University of Aarhus in Denmark provided the utmost quality SiGe structures for my {311 great colleague, supervisor, and friend) grew the B-doped SiGe structures. J. Liu of Varian

  15. High Performance Polycrystalline SiGe Thin Film Transistors Using Al2O3 Gate Insulator

    E-Print Network [OSTI]

    1 High Performance Polycrystalline SiGe Thin Film Transistors Using Al2O3 Gate Insulator Zhonghe as the gate insulator for low temperature (SiGe thin film transistors (TFTs) has been between the Al2O3 and the SiGe channel layer is sufficiently passivated to make Al2O3 a better alternative

  16. Design of a 250-Gbit/s SiGe HBT Electrooptic Modulator

    E-Print Network [OSTI]

    Huang, Zhaoran "Rena"

    Design of a 250-Gbit/s SiGe HBT Electrooptic Modulator Volume 3, Number 5, October 2011 Tuhin Guha.1109/JPHOT.2011.2169658 1943-0655/$26.00 ©2011 IEEE #12;Design of a 250-Gbit/s SiGe HBT Electrooptic: We present a rigorous electrical and optical analysis of a highly scaled, graded- base, SiGe

  17. SiGe/Si superlattice power generators Gehong Zeng, John E. Bowers

    E-Print Network [OSTI]

    Bowers, John

    SiGe/Si superlattice power generators Gehong Zeng, John E. Bowers Department of Electrical 95064 *Corresponding Email: ali@soe.ucsc.edu, phone: (831) 459-3821 Abstract SiGe is one of the best selective emission of hot electrons through thermionic emission. SiGe/Si superlattice structures were grown

  18. Simulation of Si/SiGe Micro-Cooler by Thermal Quadrupoles Method Y. Ezzahri *(a)

    E-Print Network [OSTI]

    Simulation of Si/SiGe Micro-Cooler by Thermal Quadrupoles Method Y. Ezzahri *(a) , S. Dilhaire (a on thermal quadrupoles is presented to model the behavior of a single stage Si/SiGe micro-cooler in AC of the model with experimental reflectometry techniques is also presented. Performance of Si/SiGe micro

  19. SiGe HBT Nonlinear Phase Noise Modeling Sebastien Gribaldo, Laurent Bary and Olivier Llopis

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    SiGe HBT Nonlinear Phase Noise Modeling S´ebastien Gribaldo, Laurent Bary and Olivier Llopis LAAS model of a SiGe bipolar transistor is presented. This model includes nonlinear noise sources and is able phase noise data at different RF power level. Keywords: nonlinear noise, modelling, SiGe PACS: 85.40.Qx

  20. Dynamics of uniform Si/SiGe uniaxial strain generation on compliant insulating substrates

    E-Print Network [OSTI]

    Dynamics of uniform Si/SiGe uniaxial strain generation on compliant insulating substrates R. L on the relaxation of Si/SiGe bilayers of different geometries to obtain up to 1.0% uniaxial tensile strain in silicon and 1.5 GPa uniaxial compressive stress in SiGe [1,2]. The process generates uniform uniaxially

  1. Si/SiGe modulation-doped structures with thin buffer layers: Effect of substrate orientation

    E-Print Network [OSTI]

    Allen, Leslie H.

    Si/SiGe modulation-doped structures with thin buffer layers: Effect of substrate orientation G. L and Nomarski microscopy. In n-type modulation-doped Si-SiGe structures, the band structure is type II where SiGe layer, generally on top of the strained Si, is intentionally doped leaving the adjacent Si layer

  2. Development, implementation and verification of a physicsbased Si/SiGe

    E-Print Network [OSTI]

    Development, implementation and verification of a physics­based Si/SiGe HBT model for millimeter Abstract A physics­based large­signal model including thermal dependence has been developed for Si/SiGe HBTs. The model takes into account several effects that are important for the operation of Si/SiGe HBTs

  3. Evaluation of the Radiation Tolerance of Several Generations of SiGe Heterojunction

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    1 Evaluation of the Radiation Tolerance of Several Generations of SiGe Heterojunction Bipolar. The devices investigated were first, second and third-generation Silicon- Germanium (SiGe) Heterojunction-engineered SiGe technology [1] have potential advantages when compared with Complementary Metal Oxide

  4. IEEE BCTM1.3 Explorations for High Performance SiGe-HeterojunctionBipolar

    E-Print Network [OSTI]

    Technische Universiteit Delft

    IEEE BCTM1.3 Explorations for High Performance SiGe-HeterojunctionBipolar Transistor Integration P.Deixler@philips.com,Phone: -1 505 858 2960 Abstract We present a SiGe HBT integration-study, introducing a low-complexity integration-scheme. We demonstrate a stepped box-like SiGe base-profile designed to reduce reverse Early

  5. Block-by-Block Growth of Single-Crystalline Si/SiGe Superlattice

    E-Print Network [OSTI]

    Yang, Peidong

    Letters Block-by-Block Growth of Single-Crystalline Si/SiGe Superlattice Nanowires Yiying Wu, Rong-defined compositional profile along the wire axis. Single-crystalline nanowires with longitudinal Si/SiGe superlattice-crystalline nano- wires with Si/SiGe superlattice structure are obtained and thoroughly characterized using

  6. Thermionic power generation at high temperatures using SiGe/Si superlattices

    E-Print Network [OSTI]

    Thermionic power generation at high temperatures using SiGe/Si superlattices Daryoosh Vashaeea of SiGe/Si superlattices for power generation at high temperatures. A detailed theory based on Boltzmann provides only a modest improvement in the power factor. This is due to the fact that SiGe is a multivalley

  7. Plasma process-induced band-gap modifications of a strained SiGe heterostructure

    E-Print Network [OSTI]

    Misra, Durgamadhab "Durga"

    Plasma process-induced band-gap modifications of a strained SiGe heterostructure P. K. Swain,a) S the strain of coherently strained SiGe. This work investigates the change in valence-band discontinuity in plasma-exposed SiGe films due to strain relaxation by a capacitance­voltage (C­V) profiling technique

  8. IBM Systems and Technology IBM SiGe 5PAe and

    E-Print Network [OSTI]

    IBM Systems and Technology IBM SiGe 5PAe and 1KW5PAe technologies Keep pace with mobile advances SiGe offerings featuring copper pillar and through-silicon-via options Take advantage of ongoing to solutions based on gallium arsenide (GaAs) technology, for example, the IBM SiGe 5PAe family offers several

  9. SiGe integrated circuits for millimeter-wave imaging and phased arrays

    E-Print Network [OSTI]

    May, Jason W.

    2009-01-01T23:59:59.000Z

    48 Chapter 4 SiGe W-Band RFIC Components . . . 4.1 W-Bandarray beamformer in 0.18- m SiGe BiCMOS technology. Thetotal power radiometer with SiGe LNA + Detec- tor, (b)

  10. Measurementof Seebeck coefficient perpendicular to SiGe superlattice , Gehang Zeng2

    E-Print Network [OSTI]

    Page 1 Measurementof Seebeck coefficient perpendicular to SiGe superlattice Yan Zhang1 , Gehang to measure the Seebeck coefficient of SiGe superlattice material perpendicular to the layers1 . Successful of the SiGe superlattice micro coolers. Extensive thermoreflectance imaging characterization was performed

  11. Development, implementation and verification of a physics-based Si/SiGe

    E-Print Network [OSTI]

    Development, implementation and verification of a physics-based Si/SiGe HBT model for millimeter Abstract A physics-based large-signal model including thermal dependence has been developed for Si/SiGe HBTs. The model takes into account several effects that are important for the operation of Si/SiGe HBTs

  12. Study of thermomechanical properties of Si/SiGe superlattices using femtosecond transient thermoreflectance technique

    E-Print Network [OSTI]

    Study of thermomechanical properties of Si/SiGe superlattices using femtosecond transient the thermomechanical properties of two Si/SiGe superlattices. A theoretical model is presented which agrees well-lattice vectors is smaller.8 In the experiments reported here we have applied a FTT technique to study two Si/SiGe

  13. P-type SiGe/Si Superlattice Cooler Xiaofeng Fan, Gehong Zeng, Edward Croke1

    E-Print Network [OSTI]

    P-type SiGe/Si Superlattice Cooler Xiaofeng Fan, Gehong Zeng, Edward Croke1 , Gerry Robinson, Chris and characterization of single element p-type SiGe/Si superlattice coolers are described. Superlattice structures were]. SiGe is a good thermoelectric material especially for high temperature applications [11

  14. Buckling suppression of SiGe islands on compliant substrates Haizhou Yina)

    E-Print Network [OSTI]

    Duffy, Thomas S.

    Buckling suppression of SiGe islands on compliant substrates Haizhou Yina) Center for Photonics structure made of SiGe and a cap layer were studied by both modeling and experiment. Both epitaxial silicon and accelerate the lateral relaxation, so that larger, flat, relaxed SiGe islands can be achieved. Using a 31 nm

  15. The revolution in SiGe: impact on device electronics D.L. Haramea,*

    E-Print Network [OSTI]

    Rieh, Jae-Sung

    The revolution in SiGe: impact on device electronics D.L. Haramea,* , S.J. Koesterb , G. Freemanc, Hopewell Junction, NY, USA d Georgia Technical University, Atlanta, GA, USA Abstract SiGe is having a major impact in device electronics. The most mature application is the SiGe BiCMOS technology which

  16. Measurement of the neutron-capture cross section of 76Ge and 74Ge below 15 MeV and its relevance to 0??? decay searches of 76Ge

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

    Bhike, Megha; Fallin, B.; Tornow, W.

    2015-02-01T23:59:59.000Z

    The neutron radiative-capture cross section of 76Ge was measured between 0.4 and 14.8 MeV using the activation technique. Germanium samples with the isotopic abundance of View the MathML source?86%Ge76 and View the MathML source?14%Ge74 used in the 0???0??? searches by the GERDA and Majorana Collaborations were irradiated with monoenergetic neutrons produced at eleven energies via the View the MathML sourceH3(p,n)He3, View the MathML sourceH2(d,n)He3 and View the MathML sourceH3(d,n)He4 reactions. Previously, data existed only at thermal energies and at 14 MeV. As a by-product, capture cross-section data were also obtained for 74Ge at neutron energies below 8 MeV. Indium andmore »gold foils were irradiated simultaneously for neutron fluence determination. High-resolution ?-ray spectroscopy was used to determine the ?-ray activity of the daughter nuclei of interest. For the 76Ge total capture cross section the present data are in good agreement with the TENDL-2013 model calculations and the ENDF/B-VII.1 evaluations, while for the View the MathML sourceGe74(n,?)Ge75 reaction, the present data are about a factor of two larger than predicted. It was found that the View the MathML sourceGe74(n,?)Ge75 yield in the High-Purity Germanium (HPGe) detectors used by the GERDA and Majorana Collaborations is only about a factor of two smaller than the View the MathML sourceGe76(n,?)Ge77 yield due to the larger cross section of the former reaction.« less

  17. Effect of different chemical treatments of surface on the height of Al-p-SiGe and Au-n-SiGe barriers

    SciTech Connect (OSTI)

    Atabaev, I. G., E-mail: atvi@uzsci.net; Matchanov, N. A.; Hajiev, M. U., E-mail: hajiev_mardonbek@mail.ru; Pak, V.; Saliev, T. M. [Academy of Sciences of Uzbekistan, Starodubtsev Physicotechnical Institute (Uzbekistan)

    2010-05-15T23:59:59.000Z

    The effect of different chemical treatments on the properties of Au-n-SiGe and Al-p-SiGe Schottky barriers has been investigated. Etching under different conditions was used to prepare surfaces with different densities of surface states (D{sub ss}). It is shown that the barrier height in the structures under study correlates with the D{sub ss} value and germanium content in the Si{sub 1-x}Ge{sub x} alloy.

  18. The 12 GeV Energy Upgrade at Jefferson Laboratory

    SciTech Connect (OSTI)

    Pilat, Fulvia C.

    2012-09-01T23:59:59.000Z

    Two new cryomodules and an extensive upgrade of the bending magnets at Jefferson Lab has been recently completed in preparation for the full energy upgrade in about one year. Jefferson Laboratory has undertaken a major upgrade of its flagship facility, the CW re-circulating CEBAF linac, with the goal of doubling the linac energy to 12 GeV. I will discuss here the main scope and timeline of the upgrade and report on recent accomplishments and the present status. I will then discuss in more detail the core of the upgrade, the new additional C100 cryomodules, their production, tests and recent successful performance. I will then conclude by looking at the future plans of Jefferson Laboratory, from the commissioning and operations of the 12 GeV CEBAF to the design of the MEIC electron ion collider.

  19. Evaporation-based Ge/.sup.68 Ga Separation

    DOE Patents [OSTI]

    Mirzadeh, Saed (Albuquerque, NM); Whipple, Richard E. (Los Alamos, NM); Grant, Patrick M. (Los Alamos, NM); O'Brien, Jr., Harold A. (Los Alamos, NM)

    1981-01-01T23:59:59.000Z

    Micro concentrations of .sup.68 Ga in secular equilibrium with .sup.68 Ge in strong aqueous HCl solution may readily be separated in ionic form from the .sup.68 Ge for biomedical use by evaporating the solution to dryness and then leaching the .sup.68 Ga from the container walls with dilute aqueous solutions of HCl or NaCl. The chloro-germanide produced during the evaporation may be quantitatively recovered to be used again as a source of .sup.68 Ga. If the solution is distilled to remove any oxidizing agents which may be present as impurities, the separation factor may easily exceed 10.sup.5. The separation is easily completed and the .sup.68 Ga made available in ionic form in 30 minutes or less.

  20. Partners for progress in HVDC: GE and EPRI

    SciTech Connect (OSTI)

    Damsky, B.L. (HVDC Projects Operation, Collingdale, PA); Ladden, J.M.

    1983-01-01T23:59:59.000Z

    Since the first solid-state HVDC system was installed at Eel River in 1971, there have been enormous strides in component capability and control algorithm sophistication. Benefits include reduction in cost and power losses, smaller size and improved system stability - all achieved with the same high reliability. These improvements have been achieved through development programs which required a commitment of considerable resources made possible because GE considers HVDC an important area of growth and because EPRI has consistently supported HVDC projects. Some developments from the GE-EPRI partnership for progress in HVDC technology are already being offered and others are in the process of commercialization. These on-going programs assure that future improvements will continue to make HVDC a more attractive alternative for meeting the utility industry's needs.

  1. Axial SiGe Heteronanowire Tunneling Field-Effect Transistors

    SciTech Connect (OSTI)

    Le, Son T.; Jannaty, P.; Luo, Xu; Zaslavsky, A.; Perea, Daniel E.; Dayeh, Shadi A.; Picraux, Samuel T.

    2012-10-31T23:59:59.000Z

    We present silicon-compatible tri-gated p-Ge/i-Si/n-Si axial heteronanowire tunneling field-effect transistors (TFETs), where on-state tunneling occurs in the Ge drain section, while off-state leakage is dominated by the Si junction in the source. Our TFETs have high ION ~ 2 µA/µm, fully suppressed ambipolarity, and a sub-threshold slope SS ~ 140 mV/decade over 4 decades of current with lowest SS ~ 50 mV/decade. Device operation in the tunneling mode is confirmed by three-dimensional TCAD simulation. Interestingly, in addition to the TFET mode, our devices work as standard nanowire FETs with good ION/IOFF ratio when the source-drain junction is forward-biased. The improved transport in both biasing modes confirms the benefits of utilizing bandgap engineered axial nanowires for enhancing device performance.

  2. Calculation of thermal parameters of SiGe microbolometers

    E-Print Network [OSTI]

    Voitsekhovskii, A V; Yuryev, V A; Nesmelov, S N; 10.1007/s11182-008-9015-4

    2012-01-01T23:59:59.000Z

    The thermal parameters of a SiGe microbolometer were calculated using numerical modeling. The calculated thermal conduction and thermal response time are in good agreement with the values found experimentally and range between 2x10$^-7$ and 7x10$^-8$ W/K and 1.5 and 4.5 ms, respectively. High sensitivity of microbolometer is achieved due to optimization of the thermal response time and thermal conduction by fitting the geometry of supporting heat-removing legs or by selection of a suitable material providing boundary thermal resistance higher than 8x10$^-3$ cm$^2$K/W at the SiGe interface.

  3. Proton-proton Scattering Above 3 GeV/c

    SciTech Connect (OSTI)

    A. Sibirtsev, J. Haidenbauer, H.-W. Hammer S. Krewald ,Ulf-G. Meissner

    2010-01-01T23:59:59.000Z

    A large set of data on proton-proton differential cross sections, analyzing powers and the double-polarization parameter A{sub NN} is analyzed employing the Regge formalism. We find that the data available at proton beam momenta from 3 GeV/c to 50 GeV/c exhibit features that are very well in line with the general characteristics of Regge phenomenology and can be described with a model that includes the {rho}, {omega}, f{sub 2}, and a{sub 2} trajectories and single-Pomeron exchange. Additional data, specifically for spin-dependent observables at forward angles, would be very helpful for testing and refining our Regge model.

  4. Direct synthesis of highly textured Ge on flexible polyimide films by metal-induced crystallization

    SciTech Connect (OSTI)

    Oya, N.; Toko, K., E-mail: toko@bk.tsukuba.ac.jp; Suemasu, T. [Institute of Applied Physics, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573 (Japan); Saitoh, N.; Yoshizawa, N. [Electron Microscope Facility, TIA, AIST, 16-1 Onogawa, Tsukuba 305-8569 (Japan)

    2014-06-30T23:59:59.000Z

    The highly (111)-textured Ge thin film (50-nm thickness) is demonstrated on a flexible polyimide film via the low-temperature crystallization (325?°C) of amorphous Ge using Al as a catalyst. Covering the polyimide with insulators significantly improved the crystal quality of the resulting Ge layer. In particular, SiN covering led to 97% (111)-oriented Ge with grains 200??m in size, two orders larger than the grain size of polycrystalline Ge directly formed on the polyimide film. This achievement will give a way to realize advanced electronic and optical devices simultaneously allowing for high performance, inexpensiveness, and flexibility.

  5. Axial Ge/Si nanowire heterostructure tunnel FETs.

    SciTech Connect (OSTI)

    Dayeh, Shadi A. (Los Alamos National Laboratory); Gin, Aaron V.; Huang, Jian Yu; Picraux, Samuel Thomas (Los Alamos National Laboratory)

    2010-03-01T23:59:59.000Z

    Axial Ge/Si heterostructure nanowires (NWs) allow energy band-edge engineering along the axis of the NW, which is the charge transport direction, and the realization of asymmetric devices for novel device architectures. This work reports on two significant advances in the area of heterostructure NWs and tunnel FETs: (i) the realization of 100% compositionally modulated Si/Ge axial heterostructure NWs with lengths suitable for device fabrication and (ii) the design and implementation of Schottky barrier tunnel FETs on these NWs for high-on currents and suppressed ambipolar behavior. Initial prototype devices with 10 nm PECVD SiN{sub x} gate dielectric resulted in a very high current drive in excess of 100 {micro}A/{micro}m (I/{pi}D) and 10{sup 5} I{sub on}/I{sub off} ratios. Prior work on the synthesis of Ge/Si axial NW heterostructures through the VLS mechanism have resulted in axial Si/Si{sub 1-x}Ge{sub x} NW heterostructures with x{sub max} {approx} 0.3, and more recently 100% composition modulation was achieved with a solid growth catalyst. In this latter case, the thickness of the heterostructure cannot exceed few atomic layers due to the slow axial growth rate and concurrent radial deposition on the NW sidewalls leading to a mixture of axial and radial deposition, which imposes a big challenge for fabricating useful devices form these NWs in the near future. Here, we report the VLS growth of 100% doping and composition modulated axial Ge/Si heterostructure NWs with lengths appropriate for device fabrication by devising a growth procedure that eliminates Au diffusion on the NW sidewalls and minimizes random kinking in the heterostructure NWs as deduced from detailed microscopy analysis. Fig. 1 a shows a cross-sectional SEM image of epitaxial Ge/Si axial NW heterostructures grown on a Ge(111) surface. The interface abruptness in these Ge/Si heterostructure NWs is of the order of the NW diameter. Some of these NWs develop a crystallographic kink that is {approx}20{sup o} off the <111> axis at about 300 nm away from the Ge/Si interface. This provides a natural marker for placing the gate contact electrodes and gate metal at appropriate location for desired high-on current and reduced ambipolarity as shown in Fig. 2. The 1D heterostructures allow band-edge engineering in the transport direction, not easily accessible in planar devices, providing an additional degree of freedom for designing tunnel FETs (TFETs). For instance, a Ge tunnel source can be used for efficient electron/hole tunneling and a Si drain can be used for reduced back-tunneling and ambipolar behavior. Interface abruptness on the other hand (particularly for doping) imposes challenges in these structures and others for realizing high performance TFETs in p-i-n junctions. Since the metal-semiconductor contacts provide a sharp interface with band-edge control, we use properly designed Schottky contacts (aided by 3D Silvaco simulations) as the tunnel barriers both at the source and drain and utilize the asymmetry in the Ge/Si channel bandgap to reduce ambipolar transport behavior generally observed in TFETs. Fig. 3 shows the room-temperature transfer curves of a Ge/Si heterostructure TFET (H-TFET) for different V{sub DS} values showing a maximum on-current of {approx}7 {micro}A, {approx}170 mV/decade inverse subthreshold slope and 5 orders of magnitude I{sub on}/I{sub off} ratios for all V{sub DS} biases considered here. This high on-current value is {approx}1750 X higher than that obtained with Si p-i-n{sup +} NW TFETs and {approx}35 X higher than that obtained with CNT TFET. The I{sub on}/I{sub off} ratio and inverse subthreshold slope compare favorably to that of Si {approx} 10{sup 3} I{sub on}/I{sub off} and {approx} 800 mV/decade SS{sup -1} but lags behind those of CNT TFET due to poor PECVD nitride gate oxide quality ({var_epsilon}{sub r} {approx} 3-4). The asymmetry in the Schottky barrier heights used here eliminates the stringent requirements of abrupt doped interfaces used in p-i-n based TFETs, which is hard to achieve both in thin-film and

  6. GeV emission from Gamma-Ray Burst afterglows

    E-Print Network [OSTI]

    A. Panaitescu

    2008-01-10T23:59:59.000Z

    We calculate the GeV afterglow emission expected from a few mechanisms related to GRBs and their afterglows. Given the brightness of the early X-ray afterglow emission measured by Swift/XRT, GLAST/LAT should detect the self-Compton emission from the forward-shock driven by the GRB ejecta into the circumburst medium. Novel features discovered by Swift in X-ray afterglows (plateaus and chromatic light-curve breaks) indicate the existence of a pair-enriched, relativistic outflow located behind the forward shock. Bulk and inverse-Compton upscattering of the prompt GRB emission by such outflows provide another source of GeV afterglow emission detectable by LAT. The large-angle burst emission and synchrotron forward-shock emission are, most likely, too dim at high photon energy to be observed by LAT. The spectral slope of the high-energy afterglow emission and its decay rate (if it can be measured) allow the identification of the mechanism producing the GeV transient emission following GRBs.

  7. Gamma-Ray Bursts Above 1 GeV

    E-Print Network [OSTI]

    Matthew G. Baring

    1997-11-21T23:59:59.000Z

    One of the principal results obtained by the Compton Gamma Ray Observatory relating to the study of gamma-ray bursts was the detection by the EGRET instrument of energetic ($>$100 MeV) photons from a handful of bright bursts. The most extreme of these was the single 18 GeV photon from the GRB940217 source. Given EGRET's sensitivity and limited field of view, the detection rate implies that such high energy emission may be ubiquitous in bursts. Hence expectations that bursts emit out to at least TeV energies are quite realistic, and the associated target-of-opportunity activity of the TeV gamma-ray community is well-founded. This review summarizes the observations and a handful of theoretical models for generating GeV--TeV emission in bursts sources, outlining possible ways that future positive detections could discriminate between different scenarios. The power of observations in the GeV--TeV range to distinguish between spectral structure intrinsic to bursts and that due to the intervening medium between source and observer is also discussed.

  8. Exclusive processes at JLab at 6 GeV

    SciTech Connect (OSTI)

    Kim, Andrey [University of Connecticut, JLAB

    2015-01-01T23:59:59.000Z

    Deeply virtual exclusive reactions provide a unique opportunity to probe the complex internal structure of the nucleon. They allow to access information about the correlations between parton transverse spatial and longitudinal momentum distributions from experimental observables. Dedicated experiments to study Deeply Virtual Compton Scattering (DVCS) and Deeply Virtual Meson Production (DVMP) have been carried out at Jefferson Lab using continuous electron beam with energies up to 6 GeV. Unpolarized cross sections, beam, target and double spin asymmetries have been measured for DVCS as well as for ?0 exclusive electroproduction. The data from Hall B provide a wide kinematic coverage with Q2=1-4.5 GeV2, xB=0.1-0.5, and ?t up to 2 GeV2. Hall A data have limited kinematic range partially overlapping with Hall B kinematics but provide a high accuracy measurements. Scaling tests of the DVCS cross sections provide solid evidence of twist-2 dominance, which makes chiral-even GPDs accessible even at modest Q2. We will discuss the interpretation of these data in terms of Generalized Parton Distributions (GPDs) model. Successful description of the recent CLAS ?0 exclusive production data within the framework of the GPD-based model provides a unique opportunity to access the chiral-odd GPDs.

  9. Calculation of. beta. -delayed fission of sup 180 Tl and application of the quasiparticle random-phase approximation to the prediction of. beta. sup + -decay half-lives of neutron-deficient isotopes

    SciTech Connect (OSTI)

    Staudt, A.; Hirsch, M.; Muto, K.; Klapdor-Kleingrothaus, H.V. (Max-Planck-Institut fuer Kernphysik, D-6900 Heidelberg (Federal Republic of Germany))

    1990-09-24T23:59:59.000Z

    Motivated by a recent measurement of {beta}-delayed fission in the {sup 180}Tl{r arrow}{sup 180}Hg chain, we have calculated the {beta} strength distribution {ital S}{sub {beta}} of the neutron-deficient nuclide {sup 180}Tl within the framework of the proton-neutron quasiparticle random phase approximation ({ital pn}-QRPA). The fission barrier height is then deduced from the measured {beta}-delayed fission probability {ital P}{sub {beta}DF}. In addition, as a test for the reliability of the theoretical strength distributions, {beta}{sup +}/EC half-lives of some isotopic chains are calculated using the {ital pn}-QRPA including both particle-hole and particle-particle Gamow-Teller residual interactions.

  10. Strained Sistrained Ge dual-channel heterostructures on relaxed Si0.5Ge0.5 for symmetric mobility p-type and n-type metal-oxide-semiconductor

    E-Print Network [OSTI]

    Strained SiÕstrained Ge dual-channel heterostructures on relaxed Si0.5Ge0.5 for symmetric mobility By growing heterostructures that combine a surface strained Si layer with a buried strained Ge layer on Si0.5Ge0.5 , we have fabricated metal-oxide-semiconductor field-effect transistors with mobility

  11. The polygallides: Yb{sub 3}Ga{sub 7}Ge{sub 3} and YbGa{sub 4}Ge{sub 2}

    SciTech Connect (OSTI)

    Peter, Sebastian C. [Department of Chemistry, Northwestern University, 2145N. Sheridan Road, Evanston, IL 60208 (United States); New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560064 (India); Malliakas, Christos D. [Department of Chemistry, Northwestern University, 2145N. Sheridan Road, Evanston, IL 60208 (United States); Nakotte, Heinze; Kothapilli, Karunakar [Physics Department, New Mexico State University, Las Cruces, NM 88003 (United States); Los Alamos Neutron Science Center, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Rayaprol, Sudhindra [UGC-DAE Consortium for Scientific Research, Mumbai Centre, BARC, R-5 Shed, Trombay, Mumbai 400085 (India); Schultz, Arthur J. [X-Ray Science Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Kanatzidis, Mercouri G., E-mail: m-kanatzidis@northwestern.edu [Department of Chemistry, Northwestern University, 2145N. Sheridan Road, Evanston, IL 60208 (United States); Materials Science Division, Argonne National Laboratory, Argonne, IL 60439 (United States)

    2012-03-15T23:59:59.000Z

    Yb{sub 3}Ga{sub 7}Ge{sub 3} and YbGa{sub 4}Ge{sub 2} were obtained from reactions of Yb and Ge in excess liquid gallium. The crystal structure of Yb{sub 3}Ga{sub 7}Ge{sub 3} was refined using X-ray and neutron diffraction data on selected single crystals. Yb{sub 3}Ga{sub 7}Ge{sub 3} crystallizes in the monoclinic space group C2/c with lattice constants a=12.2261(20) Angstrom-Sign , b=10.7447(20) Angstrom-Sign , c=8.4754(17) Angstrom-Sign and {beta}=110.288(30) Degree-Sign (neutron diffraction data). The crystal structure of Yb{sub 3}Ga{sub 7}Ge{sub 3} is an intergrowth of planar layers of YbGa{sub x}Ge{sub y} and puckered layers of (Ge){sub n}. YbGa{sub 4}Ge{sub 2} crystallizes in a modified PuGa{sub 6} structure type in the tetragonal polar space group I4cm with lattice constants a=b=5.9874(6) Angstrom-Sign and c=15.1178(19) Angstrom-Sign . The structure of YbGa{sub 4}Ge{sub 2} is an intergrowth of puckered Ga layers and puckered Ga{sub x}Ge{sub y} layers with Yb atoms residing within the channels formed by the connection of the two layers. Physical properties, resistivity ({rho}), magnetic susceptibility ({chi}) and specific heat (C) were measured for Yb{sub 3}Ga{sub 7}Ge{sub 3}. No magnetic ordering was observed. It was found that at low temperatures, {rho} varied as T{sup 2} and C{proportional_to}T, indicating Fermi-liquid regime in Yb{sub 3}Ga{sub 7}Ge{sub 3} at low temperatures. - Graphical abstract: The compounds Yb{sub 3}Ga{sub 7}Ge{sub 3} and YbGa{sub 4}Ge{sub 2} are obtained from reactions of Yb and Ge in excess liquid gallium. Highlights: Black-Right-Pointing-Pointer Yb{sub 3}Ga{sub 7}Ge{sub 3} and YbGa{sub 4}Ge{sub 2} are two new polygallides. Black-Right-Pointing-Pointer The crystal structure of Yb{sub 3}Ga{sub 7}Ge{sub 3} was established using neutron diffraction data. Black-Right-Pointing-Pointer YbGa{sub 4}Ge{sub 2} is one of the rare polar intermetallic compounds. Black-Right-Pointing-Pointer The physical properties of Yb{sub 3}Ga{sub 7}Ge{sub 3} point to a Fermi-liquid regime at low temperature.

  12. Impact ionization of excitons in Ge/Si structures with Ge quantum dots grown on the oxidized Si(100) surfaces

    SciTech Connect (OSTI)

    Shklyaev, A. A. [A. V. Rzhanov Institute of Semiconductor Physics, SB RAS, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Shegai, O. A. [A. V. Rzhanov Institute of Semiconductor Physics, SB RAS, Novosibirsk 630090 (Russian Federation); Nakamura, Y. [Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531 (Japan); Ichikawa, M. [Department of Applied Physics, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656 (Japan)

    2014-05-28T23:59:59.000Z

    Photoconductivity (PC) of Si/Ge structures with Ge quantum dots (QDs) grown on the Si(100) surfaces covered with the ultrathin, about 0.3–0.5?nm thick, SiO{sub 2} films is studied as a function of the interband light intensity under various lateral voltages. The structures exhibit PC with steps and a step with a peak at the step edge for low- and high-temperature grown structures, respectively. These PC features are associated with the impact ionization of QD-related excitons. The PC at step edges increases by several orders of magnitude for a certain value which is governed by the balance between rates of photo-generation, recombination, and impact ionization of excitons. The electron localization deeper in Si from the Ge QD layer in conjunction with a narrow binding-energy distribution of excitons is suggested to be the main reason that provides the sharpness of PC steps. The PC appears to be very sensitive to the impact ionization and QD preparation conditions. This allows revealing the specific characteristics of QD structures, related to their electronic and structural properties.

  13. Large-angle production of charged pions by 3 GeV/c - 12.9 GeV/c protons on beryllium, aluminium and lead targets

    E-Print Network [OSTI]

    HARP Collaboration

    2007-09-21T23:59:59.000Z

    Measurements of the double-differential $\\pi^{\\pm}$ production cross-section in the range of momentum $100 \\MeVc \\leq p beryllium, proton--aluminium and proton--lead collisions are presented. The data were taken with the HARP detector in the T9 beam line of the CERN PS. The pions were produced by proton beams in a momentum range from 3 \\GeVc to 12.9 \\GeVc hitting a target with a thickness of 5% of a nuclear interaction length. The tracking and identification of the produced particles was performed using a small-radius cylindrical time projection chamber (TPC) placed inside a solenoidal magnet. Incident particles were identified by an elaborate system of beam detectors. Results are obtained for the double-differential cross-sections at six incident proton beam momenta (3 \\GeVc, 5 \\GeVc, 8 \\GeVc, 8.9 \\GeVc (Be only), 12 \\GeVc and 12.9 \\GeVc (Al only)) and compared to previously available data.

  14. GE & AE Extension Request Form, Version 7, Sept 2012, JC Program Extension General English or Academic English

    E-Print Network [OSTI]

    Escher, Christine

    GE & AE Extension Request Form, Version 7, Sept 2012, JC Program Extension ­ General English) General English (GE) Academic English (AE) Which term will this extension begin? Fall Winter Spring Summer more sessions of GE do you wish to request? 1 2 3 4 5 6 Other ____ (GE sessions are 4 weeks) *Please

  15. Correlation Between Optical Properties And Chemical Composition Of Sputter-deposited Germanium Cxide (GeOx) Films

    SciTech Connect (OSTI)

    Murphy, Neil R.; Grant, J. T.; Sun, L.; Jones, J. G.; Jakubiak, R.; Shutthanandan, V.; Ramana, Chintalapalle V.

    2014-03-18T23:59:59.000Z

    Germanium oxide (GeOx) films were grown on (1 0 0) Si substrates by reactive Direct-Current (DC) magnetron sputter-deposition using an elemental Ge target. The effects of oxygen gas fraction, ? = O2/(Ar + O2), on the deposition rate, structure, chemical composition and optical properties of GeOx films have been investigated. The chemistry of the films exhibits an evolution from pure Ge to mixed Ge + GeO + GeO2 and then finally to GeO2 upon increasing ? from 0.00 to 1.00. Grazing incidence X-ray analysis indicates that the GeOx films grown were amorphous. The optical properties probed by spectroscopic ellipsometry indicate that the effect of ? is significant on the optical constants of the GeOx films. The measured index of refraction (n) at a wavelength (?) of 550 nm is 4.67 for films grown without any oxygen, indicating behavior characteristic of semiconducting Ge. The transition from germanium to mixed Ge + GeO + GeO2 composition is associated with a characteristic decrease in n (? = 550 nm) to 2.62 and occurs at ? = 0.25. Finally n drops to 1.60 for ? = 0.50–1.00, where the films become GeO2. A detailed correlation between ?, n, k and stoichiometry in DC sputtered GeOx films is presented and discussed.

  16. Binary Alloys of Ge and Te: Order, Voids, and the Eutectic Composition J. Akola1,2

    E-Print Network [OSTI]

    Binary Alloys of Ge and Te: Order, Voids, and the Eutectic Composition J. Akola1,2 and R. O. Jones1 and amorphous structures of Ge0:15Te0:85 and GeTe alloys are characterized using combined density functional,'' and Ge atoms (fourfold coordinated) show octahedral and tetrahedral bonding angles. Cubic local

  17. GE & AE Extension Request Form, Version 6, May 2012, JC Program Extension General English or Academic English

    E-Print Network [OSTI]

    Escher, Christine

    GE & AE Extension Request Form, Version 6, May 2012, JC Program Extension ­ General English) General English (GE) Academic English (AE) Which term will this extension begin? Fall Winter Spring Summer more sessions of GE do you wish to request? 1 2 3 4 5 6 Other ____ (GE sessions are 4 weeks) *Please

  18. GE & AE Program Change Request Form, Version 12, July 2013, ML Program Change-General English or Academic English

    E-Print Network [OSTI]

    Escher, Christine

    GE & AE Program Change Request Form, Version 12, July 2013, ML Program Change-General English English student, and I would like to switch to General English. How many sessions of GE do you wish to request? 1 2 3 4 (GE sessions are 5 weeks) How many GE hours do you wish to take? 21 hours 27 hours

  19. Hot-Wire Deposition of Hydrogenated Nanocrystalline SiGe Films for Thin-Film Si Based Solar Cells

    E-Print Network [OSTI]

    Deng, Xunming

    Hot-Wire Deposition of Hydrogenated Nanocrystalline SiGe Films for Thin-Film Si Based Solar Cells bandgap absorber in an a-Si/a-SiGe/nc-SiGe(nc- Si) triple-junction solar cell due to its higher optical in an a-Si based multiple- junction solar cell. 1. INTRODUCTION Narrow bandgap amorphous SiGe (a

  20. 258 IEEE ELECTRON DEVICE LETTERS, VOL. 23, NO. 5, MAY 2002 Self-Aligned SiGe NPN Transistors With

    E-Print Network [OSTI]

    Rieh, Jae-Sung

    258 IEEE ELECTRON DEVICE LETTERS, VOL. 23, NO. 5, MAY 2002 Self-Aligned SiGe NPN Transistors, Member, IEEE Abstract--This paper reports on SiGe NPN HBTs with unity gain cutoff frequency ( )of 207 GHz (HBTs), high- speed devices, germanium, silicon, SiGe. I. INTRODUCTION THE BiCMOS silicon-germanium (SiGe

  1. Highly strain-relaxed ultrathin SiGe-on-insulator structure by Ge condensation process combined with H{sup +} irradiation and postannealing

    SciTech Connect (OSTI)

    Miyao, Masanobu; Tanaka, Masanori; Tsunoda, Isao; Sadoh, Taizoh; Enokida, Toyotsugu; Hagino, Hiroyasu; Ninomiya, Masaharu; Nakamae, Masahiko [Department of Electronics, Kyushu University, 6-10-1 Hakozaki, Fukuoka 812-8581 (Japan); Analysis and Evaluation Center, Fukuryo Semicon Engineering Corporation, 1-1-1 Imajuku-Higashi, Fukuoka 819-0192 (Japan); SUMCO Corporation, 314 Nishisangao, Noda, Chiba 278-0015 (Japan); SUMCO Corporation, 2201 Oaza Kamioda, Kohoku-cho, Kishima-gun, Saga 849-0597 (Japan)

    2006-04-03T23:59:59.000Z

    Strain-relaxation process of SiGe-on-insulator (SGOI) structures in the oxidation induced Ge condensation method has been investigated as a function of the SiGe thickness. Complete relaxation was obtained for thick SGOI layers (>100 nm). However, the relaxation rates abruptly decreased with decreasing SiGe thickness below 50 nm, i.e., the relaxation rate of 30% at 30 nm SiGe thickness. In order to improve this phenomenon, a method combined with H{sup +} irradiation with a medium dose (5x10{sup 15} cm{sup -2}) and postannealing (1200 deg. C) has been developed. This successfully achieved the high relaxation rate (70%) in the ultrathin SGOI (30 nm)

  2. Characterization of second-phase plates in a Gd5Ge3 intermetallic compound

    SciTech Connect (OSTI)

    Cao, Qing [Ames Laboratory; Chumbley, Leonard S. [Ames Laboratory

    2013-05-16T23:59:59.000Z

    Rare-earth compounds based on the stoichiometry R5(SixGe1?x)4 (R = rare-earth elements) exhibit many unusual features, including possessing R5(SixGe1?x)3 thin plates which always precipitate from the matrix despite efforts to suppress their formation. In an effort to better understand the unique relationship between these two intermetallic alloy systems, the bulk microstructure of the compound Gd5Ge3 was examined using scanning (SEM) and transmission electron microscopy (TEM) and optical microscopy. Surprisingly, SEM examination revealed a series of thin plates present in the Gd5Ge3 matrix similar to what is seen in Gd5Ge4. TEM observation revealed that a role reversal had occurred, with the thin plates possessing the orthorhombic structure and composition of Gd5Ge4. The orientation relationship between Gd5Ge4 thin plates and the Gd5Ge3 matrix was determined to be Graphic the same relationship reported for Gd5Ge3 plates precipitating from a Gd5Ge4 matrix. However, by exchanging the respective roles of the phases as regards matrix vs. precipitate, the total number of precipitation variants seen can be increased from two to six. The persistence with which these two intermetallic systems co-exist is truly unique. However, understanding exactly the kinetic and thermodynamic conditions that lead to their unique relationship is hampered by the high formation temperatures at which the observed reaction occurs.

  3. Chemical Bonding, Interfaces and Defects in Hafnium Oxide/Germanium Oxynitride Gate Stacks on Ge (100)

    SciTech Connect (OSTI)

    Oshima, Yasuhiro; /Stanford U., Materials Sci. Dept.; Sun, Yun; /SLAC, SSRL; Kuzum, Duygu; /Stanford U.; Sugawara, Takuya; Saraswat, Krishna C.; Pianetta, Piero; /SLAC, SSRL; McIntyre, Paul C.; /Stanford U., Materials Sci. Dept.

    2008-10-31T23:59:59.000Z

    Correlations among interface properties and chemical bonding characteristics in HfO{sub 2}/GeO{sub x}N{sub y}/Ge MIS stacks were investigated using in-situ remote nitridation of the Ge (100) surface prior to HfO{sub 2} atomic layer deposition (ALD). Ultra thin ({approx}1.1 nm), thermally stable and aqueous etch-resistant GeO{sub x}N{sub y} interfaces layers that exhibited Ge core level photoelectron spectra (PES) similar to stoichiometric Ge{sub 3}N{sub 4} were synthesized. To evaluate GeO{sub x}N{sub y}/Ge interface defects, the density of interface states (D{sub it}) was extracted by the conductance method across the band gap. Forming gas annealed (FGA) samples exhibited substantially lower D{sub it} ({approx} 1 x 10{sup 12} cm{sup -2} eV{sup -1}) than did high vacuum annealed (HVA) and inert gas anneal (IGA) samples ({approx} 1x 10{sup 13} cm{sup -2} eV{sup -1}). Germanium core level photoelectron spectra from similar FGA-treated samples detected out-diffusion of germanium oxide to the HfO{sub 2} film surface and apparent modification of chemical bonding at the GeO{sub x}N{sub y}/Ge interface, which is related to the reduced D{sub it}.

  4. Experimental evidence of improved thermoelectric properties at 300K in Si/Ge superlattice structures

    SciTech Connect (OSTI)

    Venkatasubramanian, R.; Colpitts, T.; Watko, E.; Malta, D. [Research Triangle Inst., Research Triangle Park, NC (United States)

    1997-04-01T23:59:59.000Z

    The authors have found that it may be possible to obtain significant enhancement in ZT at 300 K, over conventional bulk SiGe alloys, through the use of Si/Ge Superlattice (SL) structures. The Seebeck coefficient in Si/Ge SL structures was observed to increase rapidly with decreasing SL period with no loss of electrical conductivity. The carrier mobilities in Si/Ge SLs were higher than in a comparable thin-film Si/Ge alloy. The best power factor of the short-period Si/Ge SLs is 112.2 {micro}W/K{sup 2} cm, over five-fold better than state-of-the-art n-type, bulk SiGe alloys. Approximately a two to four-fold reduction in thermal conductivity in short-period SL structures, compared to bulk SiGe alloy, was observed. The authors estimate at least a factor of five improvement over current state-of-the-art SiGe alloys, in several Si/Ge SL samples with periodicity of {approximately}45 to 75 {angstrom}. The results of this study are promising, but tentative due to the possible effects of substrate and the developmental nature of the thermoelectric property measurements.

  5. Synthesis, crystal structure and properties of [(dien){sub 2}Mn]Ge{sub 2}S{sub 4} with mixed-valent Ge centers

    SciTech Connect (OSTI)

    Yue, Cheng-Yang; Yuan, Zhuang-Dong; Zhang, Lu-Ge; Wang, Ya-Bai; Liu, Guo-Dong; Gong, Liao-Kuo [Key Laboratory of Inorganic Chemistry in Universities of Shandong, Department of Chemistry and Chemical Engineering, Jining University, Qufu, Shandong 273155 (China); Lei, Xiao-Wu, E-mail: xwlei_jnu@163.com [Key Laboratory of Inorganic Chemistry in Universities of Shandong, Department of Chemistry and Chemical Engineering, Jining University, Qufu, Shandong 273155 (China); State Key Laboratory of Crystal Materials, Institute of Crystal Materials, Shandong University, Jinan, Shandong 250100 (China)

    2013-10-15T23:59:59.000Z

    One new manganese thiogermanate, [(dien){sub 2}Mn]Ge{sub 2}S{sub 4} (dien=diethylenetriamine), was prepared under mild solvothermal conditions and structurally and spectroscopically characterized. The title compound crystallizes in the orthorhombic system, chiral space group P2{sub 1}2{sub 1}2{sub 1} (no. 19) with a=9.113(4) Å, b=12.475(5) Å, c=17.077(7) Å, V=1941.5(15) Å{sup 3} and Z=4. Its structure features a three-dimensional (3D) network composed of a one-dimensional (1D) [Ge{sub 2}S{sub 4}]{sup 2?} anionic chain and a [(dien){sub 2}Mn]{sup 2+} complex interconnected via various hydrogen bonds. The most interesting structural feature of the compound is the presence of two different oxidation states of germanium centers in the 1D [Ge{sub 2}S{sub 4}]{sup 2?} chain, which is also supported by the result of X-ray photoelectron spectroscopy measurement. The optical property of the title compound has also been studied by UV–vis spectra. - Graphical abstract: One new thiogermanate, [(dien){sub 2}Mn]Ge{sub 2}S{sub 4}, contains a one-dimensional [Ge{sub 2}S{sub 4}]{sup 2?} anionic chain with two different oxidation states of germanium centers. Display Omitted - Highlights: • One new manganese thiogermanate [(dien){sub 2}Mn]Ge{sub 2}S{sub 4} was prepared. • The compound features 1D [Ge{sub 2}S{sub 4}]{sup 2?} chain composed of [Ge{sup II}S{sub 4}] and [Ge{sup IV}S{sub 4}] tetrahedra. • The first example of inorganic–organic hybrid thiogermanates with mixed valent Ge centers.

  6. Formation of nickel germanide on SiO{sub 2}-capped n-Ge to lower its Schottky barrier height

    SciTech Connect (OSTI)

    Lin, Guangyang; Tang, Mengrao; Li, Cheng, E-mail: lich@xmu.edu.cn; Huang, Shihao; Lu, Weifang; Wang, Chen; Yan, Guangming; Chen, Songyan [Semiconductor Photonics Research Center, Department of Physics, Xiamen University, Xiamen, Fujian 361005 (China)] [Semiconductor Photonics Research Center, Department of Physics, Xiamen University, Xiamen, Fujian 361005 (China)

    2013-12-16T23:59:59.000Z

    In this Letter, NiGe/SiO{sub 2}/n-Ge ohmic contacts were demonstrated with Ge, rather than Ni, diffusion through the ion-implanted SiO{sub 2} films to form NiGe. The equivalent Schottky barrier height reduced from 0.58?eV for NiGe/n-Ge to ohmic contact. The anomalous diffusion behavior and accumulation of Ge in the SiO{sub 2} near the NiGe/SiO{sub 2} interface can be explained by vacancy-enhanced Ge diffusion. It is proposed that the presence of vacancies and Ge atoms embedded in the SiO{sub 2} layer play a significant role in the current enhancement by generation of multiple levels in the SiO{sub 2} band gap.

  7. GE & AE Program Change Form, Version 9, May 2012, JC Program Change General English or Academic English

    E-Print Network [OSTI]

    Escher, Christine

    GE & AE Program Change Form, Version 9, May 2012, JC Program Change ­ General English or Academic to GE. How many more sessions of GE do you wish to request? 1 2 3 4 5 6 How many GE hours do you wish to take? 21 hours 27 hours 2) ____ I am a GE student, and I would like to switch to AE. How many more

  8. Reliable reduction of Fermi-level pinning at atomically matched metal/Ge interfaces by sulfur treatment

    SciTech Connect (OSTI)

    Kasahara, K.; Yamada, S.; Miyao, M. [Department of Electronics, Kyushu University, 744 Motooka, Fukuoka 819-0395 (Japan); Sakurai, T.; Sawano, K.; Nohira, H. [Advanced Research Laboratories, Tokyo City University, 8-15-1 Todoroki, Tokyo 158-0082 (Japan); Hamaya, K., E-mail: hamaya@ee.es.osaka-u.ac.jp [Department of Electronics, Kyushu University, 744 Motooka, Fukuoka 819-0395 (Japan); Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531 (Japan)

    2014-04-28T23:59:59.000Z

    This study demonstrates that by using a sulfur (S) treatment on the Ge surface, a reduction in Fermi level pinning can reproducibly be achieved at atomically matched metal/Ge(111) interfaces. The Schottky barrier height for p-type Ge can be controlled by changing the metal work function despite the metal/Ge junctions. The results indicate that the combination of atomic-arrangement matching and S treatment can remove extrinsic factors influencing Fermi level pinning at metal/Ge interfaces.

  9. Diamond turning of Si and Ge single crystals

    SciTech Connect (OSTI)

    Blake, P.; Scattergood, R.O.

    1988-12-01T23:59:59.000Z

    Single-point diamond turning studies have been completed on Si and Ge crystals. A new process model was developed for diamond turning which is based on a critical depth of cut for plastic flow-to-brittle fracture transitions. This concept, when combined with the actual machining geometry for single-point turning, predicts that {open_quotes}ductile{close_quotes} machining is a combined action of plasticity and fracture. Interrupted cutting experiments also provide a meant to directly measure the critical depth parameter for given machining conditions.

  10. The Jefferson Lab 12 GeV Upgrade

    SciTech Connect (OSTI)

    R.D. McKeown

    2011-10-01T23:59:59.000Z

    A major upgrade of the Continuous Electron Beam Accelerator Facility (CEBAF) at the Thomas Jefferson National Accelerator Facility is in progress. Construction began in 2008 and the project should be completed in 2015. The upgrade includes doubling the energy of the electron beam to 12 GeV, the addition of a new fourth experimental hall, and new experimental equipment in three of the experimental halls. A brief overview of this upgrade project is presented along with some highlights of the anticipated experimental program.

  11. The 12 GeV JLab Upgrade Project

    SciTech Connect (OSTI)

    Smith, Elton

    2009-01-01T23:59:59.000Z

    The upgrade of the CEBAF Accelerator at Jefferson Lab to 12 GeV will deliver high luminosity and high quality beams, which will open unique opportunities for studies of the quark and gluon structure of hadrons in the valence region. Such physics will be made accessible by substantial additions to the experimental equipment in combination with the increased energy reach of the upgraded machine. The emphasis of the talk will be on the program in a new experimental Hall D designed to search for gluonic excitations.

  12. HTS wire irradiation test with 8 GeV protons

    SciTech Connect (OSTI)

    S. Feher; H. Glass; Y. Huang; P.J. Limon; D.F. Orris; P. Schlabach; M.A. Tartaglia; J.C. Tompkins

    1999-11-02T23:59:59.000Z

    The radiation level at High Energy Particle Accelerators (HEPA) is relatively high. Any active component which should be close to the accelerator has to be radiation hard. Since High Temperature Superconductors (HTS) have a great potential to be used in HEPAs (e.g., in superconducting magnets, current leads, RF cavities), it is important to understand the radiation hardness of these materials. A radiation test of HTS wire (Bi-2223) was performed at Fermilab. The HTS sample was irradiated with 8 GeV protons and the relative I{sub c} was measured during the irradiation. The total radiation dose was 10 Mrad, and no I{sub c} degradation was observed.

  13. Proton Profile Function at 52.8 GeV

    E-Print Network [OSTI]

    Geovanna L. P. Silva; Marcio J. Menon; Regina F. Avila

    2008-02-12T23:59:59.000Z

    We present the results of a novel model-independent fit to elastic proton-proton differential cross section data at $\\sqrt s$ = 52.8 GeV. Taking into account the error propagation from the fit parameters, we determine the scattering amplitude in the impact parameter space (the proton profile function) and its statistical uncertainty region. We show that both the real and imaginary parts of the profile are consistent with two dynamical contributions, one from a central dense region, up to roughly 1 fm and another from a peripheral evanescent region from 1 to 3 fm.

  14. The 12 GeV JLab Upgrade Project

    E-Print Network [OSTI]

    Elton S. Smith

    2009-01-21T23:59:59.000Z

    The upgrade of the CEBAF Accelerator at Jefferson Lab to 12 GeV will deliver high luminosity and high quality beams, which will open unique opportunities for studies of the quark and gluon structure of hadrons in the valence region. Such physics will be made accessible by substantial additions to the experimental equipment in combination with the increased energy reach of the upgraded machine. The emphasis of the talk will be on the program in a new experimental Hall D designed to search for gluonic excitations.

  15. GE Progetti 3i Spa | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual SiteofEvaluating A PotentialJumpGermanFife EnergyFreightFulongFuturo LatinoEngineeringGE

  16. Secretary Chu Speaks at GE Solar Facility | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreakingMay 2015ParentsMiddle SchoolPhysics | DepartmentRecovery ActofGE Solar

  17. ORNL Partners with GE on New Hybrid | ornl.gov

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible for Renewable Energy:Nanowire3627Homeland SecurityJonathan Mbah andORNL Partners with GE

  18. Northern Colorado Wind Energy Center (GE) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation, searchOfRoseConcerns Jumpsource History View NewNorthern Arizona UniversityGE)

  19. Notrees 1B (GE Energy) Wind Farm | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation, searchOfRoseConcerns Jumpsource History ViewTexas:Notrees 1B (GE Energy) Wind

  20. Top of the World (GE) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-f <MaintainedInformationThePty LtdOpenHabitatandWind Farm Jump to:GE)

  1. Microgravity and Vision in Astronauts | GE Global Research

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHighand Retrievals fromprocess usedGE Researchers Study Microgravity and

  2. Cedar Creek Wind Farm II (GE) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty EditCalifornia:Power LPInformationCashtonGoCaterpillar Jump to:CeCap LLPII (GE)

  3. Crystal Lake - GE Energy Wind Farm | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty EditCalifornia:PowerCER.pngRoofs and HeatOpen Energy Information8) Wind FarmGE

  4. Extended Battery Life in Electric Vehicles | GE Global Research

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) Environmental Assessments (EA) /EmailMolecularGE, Ford, University of Michigan Extend

  5. FIRST Robotics at NY Tech Valley | GE Global Research

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) Environmental Assessments (EA) /EmailMolecularGE,Ozone LayerFES UserFORFaxPit

  6. Observation of optical spin injection into Ge-based structures at room temperature

    SciTech Connect (OSTI)

    Yasutake, Yuhsuke; Hayashi, Shuhei; Fukatsu, Susumu [Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro, Tokyo 153-8902 (Japan)] [Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro, Tokyo 153-8902 (Japan); Yaguchi, Hiroyuki [Graduate School of Science and Engineering, Saitama University, Shimo-Okubo 255, Sakura, Saitama 338-8570 (Japan)] [Graduate School of Science and Engineering, Saitama University, Shimo-Okubo 255, Sakura, Saitama 338-8570 (Japan)

    2013-06-17T23:59:59.000Z

    Non-zero spin polarization induced by optical orientation was clearly observed at room temperature in a Ge/Ge{sub 0.8}Si{sub 0.2} quantum well grown on Ge and a Ge layer grown on Si by molecular beam epitaxy, whereas it was absent in bulk Ge. This occurred because indirect-gap photoluminescence (PL), which can obscure the spin-polarization information carried by the direct-gap PL, was quenched by unintentional growth-related defects in the epitaxial layers. Such interpretation was confirmed by applying time gating that effectively removed the indirect-gap PL characterized by a slower rise time, which allowed us to demonstrate the existence of room-temperature spin polarization in bulk Ge.

  7. Comparative analysis of hole transport in compressively strained InSb and Ge quantum well heterostructures

    SciTech Connect (OSTI)

    Agrawal, Ashish; Barth, Michael; Madan, Himanshu; Datta, Suman [Department of Electrical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Lee, Yi-Jing; Lin, You-Ru; Wu, Cheng-Hsien; Ko, Chih-Hsin; Wann, Clement H. [Taiwan Semiconductor Manufacturing Company, Hsinchu 30078, Taiwan (China); Loubychev, Dmitri; Liu, Amy; Fastenau, Joel [IQE, Inc., Bethlehem, Pennsylvania 18015 (United States); Lindemuth, Jeff [Lake Shore Cryotronics, Westerville, Ohio 43082 (United States)

    2014-08-04T23:59:59.000Z

    Compressively strained InSb (s-InSb) and Ge (s-Ge) quantum well heterostructures are experimentally studied, with emphasis on understanding and comparing hole transport in these two-dimensional confined heterostructures. Magnetotransport measurements and bandstructure calculations indicate 2.5× lower effective mass for s-InSb compared to s-Ge quantum well at 1.9?×?10{sup 12}?cm{sup –2}. Advantage of strain-induced m* reduction is negated by higher phonon scattering, degrading hole transport at room temperature in s-InSb quantum well compared to s-Ge heterostructure. Consequently, effective injection velocity is superior in s-Ge compared to s-InSb. These results suggest s-Ge quantum well heterostructure is more favorable and promising p-channel candidate compared to s-InSb for future technology node.

  8. Tensile-strain and doping enhanced direct bandgap optical transition of n{sup +} doped Ge/GeSi quantum wells

    SciTech Connect (OSTI)

    Fan, W. J., E-mail: ewjfan@ntu.edu.sg [NOVITAS, Nanoelectronics Centre of Excellence, School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore)

    2013-11-14T23:59:59.000Z

    Band structures of tensile strained and n{sup +} doped Ge/GeSi quantum wells (QWs) are calculated by multiple-band k·p method. The energy dispersion curves of the ? and L conduction subbands are obtained. The effects of tensile strain and n{sup +} doping in Ge on direct bandgap optical gain and spontaneous radiative recombination rate spectra are investigated including the electron leakage from ? to L conduction subbands. Our results show that the optical gain and spontaneous radiative recombination rate can be significantly increased with the tensile strain, n-type doping concentration, and injection carrier density in the Ge QW. The free carrier absorption is calculated and cannot be ignored because of the heavily doped Ge. The pure TM mode polarized net optical gain up to 1153?cm{sup ?1} can be achieved for the Ge/Ge{sub 0.986}Si{sub 0.014} QW with tensile strain of 1.61% and n-type doping concentration of 30?×?10{sup 18}?cm{sup ?3}.

  9. Results on neutrinoless double beta decay of 76 Ge from Gerda Phase I

    E-Print Network [OSTI]

    Results on neutrinoless double beta decay of 76 Ge from Gerda Phase I M. Agostini,14 M. Allardt,3 E and a lower limit is derived for the half-life of neutrinoless double beta decay of 76 Ge, T0 1/2> 2.1 · 1025 double beta decay of the isotope 76 Ge. Data con- sidered in the present analysis have been collected

  10. Raman scattering in Si/SiGe nanostructures: Revealing chemical composition, strain, intermixing, and heat dissipation

    SciTech Connect (OSTI)

    Mala, S. A.; Tsybeskov, L., E-mail: tsybesko@njit.edu [Department of Electrical and Computer Engineering, New Jersey Institute of Technology, Newark, New Jersey 07102 (United States); Lockwood, D. J.; Wu, X.; Baribeau, J.-M. [National Research Council, Ottawa, Ontario K1A 0R6 (Canada)

    2014-07-07T23:59:59.000Z

    We present a quantitative analysis of Raman scattering in various Si/Si{sub 1-x}Ge{sub x} multilayered nanostructures with well-defined Ge composition (x) and layer thicknesses. Using Raman and transmission electron microscopy data, we discuss and model Si/SiGe intermixing and strain. By analyzing Stokes and anti-Stokes Raman signals, we calculate temperature and discuss heat dissipation in the samples under intense laser illumination.

  11. The Jefferson Lab program: From 6 GeV operations to the 12 GeV upgrade

    SciTech Connect (OSTI)

    Marco Battaglieri

    2012-04-01T23:59:59.000Z

    The Thomas Jefferson National Laboratory and the CEBAF accelerator operated for more than a decade, running a comprehensive scientific program that improved our understanding of the strong interaction. The facility is now moving toward an upgrade of the machine, from 6 to 12 GeV; a new experimental hall will be added and the equipment of the three existing halls will be enhanced. In this contribution some selected results from the rich physics program run at JLab, as well as the prospects for the near future, will be presented.

  12. Sideward Flow in Au + Au Collisions Between 2A GeV and 8A GeV

    E-Print Network [OSTI]

    E895 Collaboration; H. Liu; N. N. Ajitanand; J. Alexander; M. Anderson; D. Best; F. P. Brady; T. Case; W. Caskey; D. Cebra; J. Chance; B. Cole; K. Crowe; A. Das; J. Draper; M. Gilkes; S. Gushue; M. Heffner; A. Hirsch; E. Hjort; L. Huo; M. Justice; M. Kaplan; D. Keane; J. Kintner; J. Klay; D. Krofcheck; R. Lacey; M. A. Lisa; Y. M. Liu; R. McGrath; Z. Milosevich; G. Odyniec; D. Olson; S. Y. Panitkin; N. Porile; G. Rai; H. G. Ritter; J. Romero; R. Scharenberg; L. S. Schroeder; B. Srivastava; N. T. B. Stone; T. J. M. Symons; S. Wang; J. Whitfield; T. Wienold; R. Witt; L. Wood; X. Yang; W. N. Zhang; Y. Zhang

    2000-05-24T23:59:59.000Z

    Using the large acceptance Time Projection Chamber of experiment E895 at Brookhaven, measurements of collective sideward flow in Au + Au collisions at beam energies of 2, 4, 6 and 8A GeV are presented in the form of in-plane transverse momentum and the first Fourier coefficient of azimuthal anisotropy v_1. These measurements indicate a smooth variation of sideward flow as a function of beam energy. The data are compared with four nuclear transport models which have an orientation towards this energy range. All four exhibit some qualitative trends similar to those found in the data, although none shows a consistent pattern of agreement within experimental uncertainties.

  13. Search for GeV GRBs at Chacaltaya

    SciTech Connect (OSTI)

    Castellina, A.; Ghia, P. L.; Morello, C.; Trinchero, G.; Vallania, P.; Vernetto, S. [Istituto di Cosmogeofisica del C.N.R., Torino (Italy); Navarra, G.; Saavedra, O. [Dipartimento di Fisica Generale dell'Universita' di Torino (Italy); Yoshii, H. [Department of Physics, Ehime University, Ehime 790 (Japan); Kaneko, T. [Department of Physics, Okayama University, Okayama 700 (Japan); Kakimoto, K. [Department of Physics, Tokyo Institute of Technology, Meguro, Tokyo 152 (Japan); Nishi, K. [Institute of Physical and Chemical Research, Wako, Saitama 351-01 (Japan); Cabrera, R.; Urzagasti, D.; Velarde, A. [Instituto de Investigaciones Fisicas, Universidad Mayor de San Andres, La Paz (Bolivia, Plurinational State of); Barthelmy, S. D.; Butterworth, P.; Cline, T. L.; Gehrels, N. [NASA Goddard Space Flight Center, Greenbelt, Maryland 20771 (United States); Fishman, G. J. [NASA Marshall Space Flight Center, Huntsville, Alabama 35812 (United States)] (and others)

    1998-05-16T23:59:59.000Z

    In this paper we present the results of a search for GeV Gamma Ray Bursts made by the INCA experiment during the first 9 months of operation. INCA, an air shower array located at Mount Chacaltaya (Bolivia) at 5200 m a.s.l., has been searching for GRBs since December 1996. Up to August, 1997, 34 GRBs detected by BATSE occurred in the field of view of the experiment. For any burst, the counting rate of the array in the 2 hours interval around the burst trigger time has been studied. No significant excess has been observed. Assuming for the bursts a power low energy spectrum extending up to 1 TeV with a slope {alpha}=-2 and a duration of 10 s, the obtained 1 GeV-1 TeV energy fluence upper limits range from 7.9 10{sup -5} erg cm{sup -2} to 3.5 10{sup -3} erg cm{sup -2} depending on the event zenith angles.

  14. Detector development for Jefferson Lab's 12GeV Upgrade

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

    Qiang, Yi [JLAB] (ORCID:0000000170267841)

    2015-05-01T23:59:59.000Z

    Jefferson Lab will soon finish its highly anticipated 12 GeV Upgrade. With doubled maximum energy, Jefferson Lab’s Continuous Electron Beam Accelerator Facility (CEBAF) will enable a new experimental program with substantial discovery potential, addressing important topics in nuclear, hadronic and electroweak physics. In order to take full advantage of the high energy, high luminosity beam, new detectors are being developed, designed and constructed to fit the needs of different physics topics. The paper will give an overview of various new detector technologies to be used for 12 GeV experiments. It will then focus on the development of two solenoid-based spectrometers, the GlueX and SoLID spectrometers. The GlueX experiment in Hall D will study the complex properties of gluons through exotic hybrid meson spectroscopy. The GlueX spectrometer, a hermetic detector package designed for spectroscopy and the associated partial wave analysis, is currently in the final stage of construction. Hall A, on the other hand, is developing the SoLID spectrometer to capture the 3D image of the nucleon from semi-inclusive processes and to study the intrinsic properties of quarks through mirror symmetry breaking. Such a spectrometer will have the capability to handle very high event rates while still maintaining a large acceptance in the forward region.

  15. 12 GeV Upgrade Project - Cryomodule Production

    SciTech Connect (OSTI)

    J. Hogan, A. Burrill, G.K. Davis, M.A. Drury, M. Wiseman

    2012-07-01T23:59:59.000Z

    The Thomas Jefferson National Accelerator Facility (Jefferson Lab) is producing ten 100+MV SRF cryomodules (C100) as part of the CEBAF 12 GeV Upgrade Project. Once installed, these cryomodules will become part of an integrated accelerator system upgrade that will result in doubling the energy of the CEBAF machine from 6 to 12 GeV. This paper will present a complete overview of the C100 cryomodule production process. The C100 cryomodule was designed to have the major components procured from private industry and assembled together at Jefferson Lab. In addition to measuring the integrated component performance, the performance of the individual components is verified prior to being released for production and assembly into a cryomodule. Following a comprehensive cold acceptance test of all subsystems, the completed C100 cryomodules are installed and commissioned in the CEBAF machine in preparation of accelerator operations. This overview of the cryomodule production process will include all principal performance measurements, acceptance criterion and up to date status of current activities.

  16. Detector development for Jefferson Lab's 12GeV Upgrade

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

    Qiang, Yi

    2015-05-01T23:59:59.000Z

    Jefferson Lab will soon finish its highly anticipated 12 GeV Upgrade. With doubled maximum energy, Jefferson Lab’s Continuous Electron Beam Accelerator Facility (CEBAF) will enable a new experimental program with substantial discovery potential, addressing important topics in nuclear, hadronic and electroweak physics. In order to take full advantage of the high energy, high luminosity beam, new detectors are being developed, designed and constructed to fit the needs of different physics topics. The paper will give an overview of various new detector technologies to be used for 12 GeV experiments. It will then focus on the development of two solenoid-based spectrometers,more »the GlueX and SoLID spectrometers. The GlueX experiment in Hall D will study the complex properties of gluons through exotic hybrid meson spectroscopy. The GlueX spectrometer, a hermetic detector package designed for spectroscopy and the associated partial wave analysis, is currently in the final stage of construction. Hall A, on the other hand, is developing the SoLID spectrometer to capture the 3D image of the nucleon from semi-inclusive processes and to study the intrinsic properties of quarks through mirror symmetry breaking. Such a spectrometer will have the capability to handle very high event rates while still maintaining a large acceptance in the forward region.« less

  17. Pressure-induced transformations in amorphous Si-Ge alloy

    SciTech Connect (OSTI)

    Coppari, F.; Polian, A.; Menguy, N.; Trapananti, A.; Congeduti, A.; Newville, M.; Prakapenka, V.B.; Choi, Y.; Principi, E.; Di Cicco, A. (CNRS-UMR); (UC); (Camerino)

    2012-03-14T23:59:59.000Z

    The pressure behavior of an amorphous Si-rich SiGe alloy ({alpha}-Si{sub x}Ge{sub 1-x}, x = 0.75) has been investigated up to about 30 GPa, by a combination of Raman spectroscopy, x-ray absorption spectroscopy, and x-ray diffraction measurements. The trends of microscopic structural properties and of the Raman-active phonon modes are presented in the whole pressure range. Nucleation of nanocrystalline alloy particles and metallization have been observed above 12 GPa, with a range of about 2 GPa of coexistence of amorphous and crystalline phases. Transformations from the amorphous tetrahedral, to the crystalline tetragonal ({beta}-Sn) and to the simple hexagonal structures have been observed around 13.8 and 21.8 GPa. The recovered sample upon depressurization, below about 4 GPa, shows a local structure similar to the as-deposited one. Inhomogeneities of the amorphous texture at the nanometric scale, probed by high-resolution transmission electron microscopy, indicate that the recovered amorphous sample has a different ordering at this scale, and therefore the transformations can not be considered fully reversible. The role of disordered grain boundaries at high pressure and the possible presence of a high-density amorphous phase are discussed.

  18. Radiation microscope for SEE testing using GeV ions.

    SciTech Connect (OSTI)

    Doyle, Barney Lee; Knapp, James Arthur; Rossi, Paolo; Hattar, Khalid M.; Vizkelethy, Gyorgy; Brice, David Kenneth; Branson, Janelle V.

    2009-09-01T23:59:59.000Z

    Radiation Effects Microscopy is an extremely useful technique in failure analysis of electronic parts used in radiation environment. It also provides much needed support for development of radiation hard components used in spacecraft and nuclear weapons. As the IC manufacturing technology progresses, more and more overlayers are used; therefore, the sensitive region of the part is getting farther and farther from the surface. The thickness of these overlayers is so large today that the traditional microbeams, which are used for REM are unable to reach the sensitive regions. As a result, higher ion beam energies have to be used (> GeV), which are available only at cyclotrons. Since it is extremely complicated to focus these GeV ion beams, a new method has to be developed to perform REM at cyclotrons. We developed a new technique, Ion Photon Emission Microscopy, where instead of focusing the ion beam we use secondary photons emitted from a fluorescence layer on top of the devices being tested to determine the position of the ion hit. By recording this position information in coincidence with an SEE signal we will be able to indentify radiation sensitive regions of modern electronic parts, which will increase the efficiency of radiation hard circuits.

  19. €18.5 Million in New Research Program Funding Announced, GE...

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

    funding and collaboration models at its European Global Research Center near Munich, Germany. Mark Little, GE's Senior Vice President and Chief Technology Officer, and thought...

  20. Using 3D Painting to Build and Repair Parts | GE Global Research

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

    a part or add material to repair an existing part. Cold spray is part of GE's expanded additive manufacturing toolkit. An error occurred. Unable to execute Javascript. nteneh...

  1. GE to DOE General Counsel; Re:Request for Comment on Large Capacity...

    Office of Environmental Management (EM)

    Clothes Washers GE urges the department engage in rulmaking to amend the clothes washer test procedure to reflect efficiency standards of large-capacity residential clothes washer...

  2. AVTA: GE Energy WattStation AC Level 2 Charging System Testing...

    Energy Savers [EERE]

    2012 More Documents & Publications AVTA: Aerovironment AC Level 2 Charging System Testing Results AVTA: GE Smart Grid Capable AC Level 2 Testing Results AVTA: Siemens-VersiCharge...

  3. Sr{sub 7}Ge{sub 6}, Ba{sub 7}Ge{sub 6} and Ba{sub 3}Sn{sub 2} -Three new binary compounds containing dumbbells and four-membered chains of tetrel atoms with considerable Ge-Ge {pi}-bonding character

    SciTech Connect (OSTI)

    Siggelkow, Lisa; Hlukhyy, Viktor [Department Chemie, Technische Universitaet Muenchen, Lichtenbergstr. 4, D-85747 Garching (Germany); Faessler, Thomas F., E-mail: thomas.faessler@lrz.tum.de [Department Chemie, Technische Universitaet Muenchen, Lichtenbergstr. 4, D-85747 Garching (Germany)

    2012-07-15T23:59:59.000Z

    The germanides Sr{sub 7}Ge{sub 6} and Ba{sub 7}Ge{sub 6} as well as the stannide Ba{sub 3}Sn{sub 2} were prepared by arc melting and annealing in welded tantalum ampoules using induction as well as resistance furnaces. The compounds were investigated by powder and single crystal X-ray diffraction. Sr{sub 7}Ge{sub 6} and Ba{sub 7}Ge{sub 6} crystallize in the Ca{sub 7}Sn{sub 6} structure type (space group Pmna, Z=4: a=7.777(2) A, b=23.595(4) A, c=8.563(2) A, wR{sub 2}=0.081 (all data), 2175 independent reflections, 64 variable parameters for Sr{sub 7}Ge{sub 6} and a=8.0853(6) A, b=24.545(2) A, c=8.9782(8) A, wR{sub 2}=0.085 (all data), 2307 independent reflections, 64 variable parameters for Ba{sub 7}Ge{sub 6}). Ba{sub 3}Sn{sub 2} crystallizes in an own structure type with the space group P4{sub 3}2{sub 1}2, Z=4, a=6.6854(2) A, c=17.842(2) A, wR{sub 2}=0.037 (all data), 1163 independent reflections, 25 variable parameters. In Sr{sub 7}Ge{sub 6} and Ba{sub 7}Ge{sub 6} the Ge atoms are arranged as Ge{sub 2} dumbbells and Ge{sub 4} four-membered atom chains. Their crystal structures cannot be rationalized according to the (8-N) rule. In contrast, Ba{sub 3}Sn{sub 2} presents Sn{sub 2} dumbbells as a main structural motif and thereby can be described as an electron precise Zintl phase. The chemical bonding situation in these structures is discussed on the basis of partial and total Density Of States (DOS) curves, band structures including fatbands, topological analysis of the Electron Localization Function (ELF) as well as Bader analysis of the bond critical points using the programs TB-LMTO-ASA and WIEN2K. While Ba{sub 3}Sn{sub 2} reveals semiconducting behaviour, all germanides Ae{sub 7}Ge{sub 6} (Ae=Ca, Sr, and Ba) show metallic properties and a considerable {pi}-bonding character between the Ge atoms of the four-membered chains and the dumbbells. The {pi}-bonding character of the germanides is best reflected by the resonance hybrid structures {l_brace}[Ge-Ge]{sup 6-}/[Ge-{sup ....}Ge-{sup ....}Ge-{sup ....}Ge]{sup 8-}{r_brace}{r_reversible}{l_brace}[Ge=Ge]{sup 4-}/[Ge-Ge-Ge-Ge]{sup 10-}{r_brace}. - Graphical abstract: The structure of Ba{sub 3}Sn{sub 2} contains Sn{sub 2} dumbbells as a main structural motif and thereby can be described as an electron precise Zintl phase. Ge{sub 2} dumbbells and Ge{sub 4} four-membered atom chains are the predominant features in Sr{sub 7}Ge{sub 6} and Ba{sub 7}Ge{sub 6}. Their crystal structures cannot be rationalized according to the (8-N) rule. While Ba{sub 3}Sn{sub 2} reveals semiconducting behaviour, the germanides Ae{sub 7}Ge{sub 6} (Ae=Ca, Sr, and Ba) show metallic properties and a considerable {pi}-bonding character between the Ge atoms of the four-membered chains and the dumbbells. Highlights: Black-Right-Pointing-Pointer The germanides Sr{sub 7}Ge{sub 6} and Ba{sub 7}Ge{sub 6} as well as the stannide Ba{sub 3}Sn{sub 2} have been synthesized. Black-Right-Pointing-Pointer In Sr{sub 7}Ge{sub 6} and Ba{sub 7}Ge{sub 6} the Ge atoms are arranged as dumbbells and four-membered atom chains. Black-Right-Pointing-Pointer Ba{sub 3}Sn{sub 2} presents Sn{sub 2} dumbbells as a main structural motif. Black-Right-Pointing-Pointer The chemical bonding situation within these structures is discussed.

  4. Altran and GE Announce Intention to Form an Alliance to Drive...

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

    SAN RAMON, CALIF. - June 17, 2015 - Altran, global leader in innovation and high-tech engineering consulting and General Electric (NYSE: GE) today announced they have signed a...

  5. 5 Top Trends From the Women and Technology Symposium | GE Global...

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

    mindset right from the design stage. 5. It's critical to include entire team in the product lifecycle The discussion from the GE Transportation brought out critical aspects...

  6. Effect of stacking sequence on crystallization in Al/a-Ge bilayer thin films

    SciTech Connect (OSTI)

    Zhang, Tianwei; Zhang, Weilin; Ma, Fei, E-mail: mafei@mail.xjtu.edu.cn, E-mail: kwxu@mail.xjtu.edu.cn [State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, Shaanxi 710049 (China); Huang, Yuhong [College of Physics and Information Technology, Shaanxi Normal University, Xi'an, Shaanxi 710062 (China); Xu, Kewei, E-mail: mafei@mail.xjtu.edu.cn, E-mail: kwxu@mail.xjtu.edu.cn [State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China and Department of Physics and Opt-electronic Engineering, Xi'an University of Arts and Science, Xi'an, Shaanxi 710065 (China)

    2014-05-15T23:59:59.000Z

    Two types of bilayer thin films with different deposition sequences, i.e., amorphous Ge under Al (a-Ge/Al) and the inverse (Al/a-Ge), were prepared by magnetron sputtering at room temperature. In-situ and ex-situ thermal annealing were compared to study the effect of the stacking sequence on crystallization of amorphous Ge. Although metal-induced crystallization occurred in both cases at low temperature, layer exchange was observed only in a-Ge/Al. In fact, compressive stress could usually be produced when Ge atoms diffused into Al grain boundaries and crystallized there. In the a-Ge/Al system, the stress could be released through diffusion of Al atoms onto the surface and formation of hillocks. Thus, grain boundary (GB) mediated crystallization was dominant in the whole process and layer exchange occurred. However, in the Al/a-Ge system, it was difficult for stress to be relaxed because the Ge sublayer and substrate restricted the diffusion of Al atoms. GB-mediated crystallization was, therefore, considerably suppressed and interface-mediated crystallization was preferred without layer exchange. This leads to distinct morphologies of dendrites in the two systems.

  7. Compositional evolution of SiGe islands on patterned Si (001) substrates

    SciTech Connect (OSTI)

    Zhang Jianjun [Institute of Semiconductor and Solid State Physics, University Linz, A-4040 Linz (Austria); Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstr. 20, D-01069 Dresden (Germany); Rastelli, Armando; Schmidt, Oliver G. [Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstr. 20, D-01069 Dresden (Germany); Bauer, Guenther [Institute of Semiconductor and Solid State Physics, University Linz, A-4040 Linz (Austria)

    2010-11-15T23:59:59.000Z

    The authors investigate, by atomic-force-microscopy-based nanotomography, the composition evolution of ordered SiGe islands grown on pit-patterned Si (001) substrates as their size and aspect ratio increase with increasing Ge deposition. Compared to islands grown on flat substrates, the ordered island arrays show improved size, shape, and compositional homogeneity. The three-dimensional composition profiles of individual pyramids, domes, and barns reveal that the Ge fraction at the base and in subsurface regions of the islands decreases with increasing amount of deposited Ge.

  8. Growth of GaN on Ge(111) by molecular beam epitaxy

    SciTech Connect (OSTI)

    Lieten, R. R.; Degroote, S.; Cheng, K.; Leys, M.; Kuijk, M.; Borghs, G. [MCP/ART, IMEC, Kapeldreef 75, 3001 Leuven (Belgium) and ETRO, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels (Belgium); MCP/ART, IMEC, Kapeldreef 75, 3001 Leuven (Belgium); ETRO, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels (Belgium); MCP/ART, IMEC, Kapeldreef 75, 3001 Leuven (Belgium)

    2006-12-18T23:59:59.000Z

    The epitaxial growth of GaN on Ge is reported. The authors found that direct growth of GaN performs exceptionally well on Ge(111) with plasma assisted molecular beam epitaxy. A streaky reflection high energy electron diffraction pattern is observed during growth. X-ray diffraction showed a rocking curve full width at half maximum of only 371 arc sec for a 38 nm GaN layer and indicates an abrupt interface between the GaN and Ge. Secondary ion mass spectrometry shows limited diffusion of Ga atoms into the Ge substrate and Ge atoms into the GaN layers. Current-voltage measurements show rectifying behavior for n-GaN on p-Ge. Their results indicate that GaN growth on Ge does not require intermediate layers, allowing the Ge substrate to be used as back contact in vertical devices. A p-n junction formed between GaN and Ge can be used in heterojunction devices.

  9. GeSn-based p-i-n photodiodes with strained active layer on a Si wafer

    SciTech Connect (OSTI)

    Tseng, H. H.; Li, H.; Mashanov, V.; Yang, Y. J.; Cheng, H. H., E-mail: hhcheng@ntu.edu.tw [Center for Condensed Matter Sciences and Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 106, Taiwan (China); Chang, G. E. [Department of Mechanical Engineering, and Advanced Institute of Manufacturing with High-tech Innovations, National Chung Cheng University, Chiayi County 62102, Taiwan (China)] [Department of Mechanical Engineering, and Advanced Institute of Manufacturing with High-tech Innovations, National Chung Cheng University, Chiayi County 62102, Taiwan (China); Soref, R. A.; Sun, G. [Department of Physics, University of Massachusetts Boston, Boston, Massachusetts 02125 (United States)] [Department of Physics, University of Massachusetts Boston, Boston, Massachusetts 02125 (United States)

    2013-12-02T23:59:59.000Z

    We report an investigation of GeSn-based p-i-n photodiodes with an active GeSn layer that is almost fully strained. The results show that (a) the response of the Ge/GeSn/Ge heterojunction photodiodes is stronger than that of the reference Ge-based photodiodes at photon energies above the 0.8 eV direct bandgap of bulk Ge (<1.55??m), and (b) the optical response extends to lower energy regions (1.55–1.80??m wavelengths) as characterized by the strained GeSn bandgap. A cusp-like spectral characteristic is observed for samples with high Sn contents, which is attributed to the significant strain-induced energy splitting of heavy and light hole bands. This work represents a step forward in developing GeSn-based infrared photodetectors.

  10. The CMS barrel calorimeter response to particle beams from 2-GeV/c to 350-GeV/c

    SciTech Connect (OSTI)

    Abdullin, S.; /Moscow, ITEP; Abramov, V.; /Serpukhov, IHEP; Acharya, B.; /Tata Inst.; Adam, N.; /Princeton U.; Adams, M.; /Illinois U., Chicago; Adzic, P.; /Belgrade U.; Akchurin, N.; /Texas Tech.; Akgun, U.; Albayrak, E.; /Iowa U.; Alemany-Fernandez, R.; Almeida, N.; /Lisbon, LIFEP /Democritos Nucl. Res. Ctr. /Virginia U. /Iowa State U.

    2009-01-01T23:59:59.000Z

    The response of the CMS barrel calorimeter (electromagnetic plus hadronic) to hadrons, electrons and muons over a wide momentum range from 2 to 350 GeV/c has been measured. To our knowledge, this is the widest range of momenta in which any calorimeter system has been studied. These tests, carried out at the H2 beam-line at CERN, provide a wealth of information, especially at low energies. The analysis of the differences in calorimeter response to charged pions, kaons, protons and antiprotons and a detailed discussion of the underlying phenomena are presented. We also show techniques that apply corrections to the signals from the considerably different electromagnetic (EB) and hadronic (HB) barrel calorimeters in reconstructing the energies of hadrons. Above 5 GeV/c, these corrections improve the energy resolution of the combined system where the stochastic term equals 84.7 {+-} 1.6% and the constant term is 7.4 {+-} 0.8%. The corrected mean response remains constant within 1.3% rms.

  11. Direct band gap optical emission from compressively strained Ge films grown on relaxed Si{sub 0.5}Ge{sub 0.5} substrate

    SciTech Connect (OSTI)

    Aluguri, R.; Manna, S.; Ray, S. K. [Department of Physics and Meteorology, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India)] [Department of Physics and Meteorology, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India)

    2013-10-14T23:59:59.000Z

    Compressively strained Ge films have been grown on relaxed Si{sub 0.5}Ge{sub 0.5} virtual substrate in ultra high vacuum using molecular beam epitaxy. Structural characterization has shown that the Ge films are compressively strained with partial strain relaxation in a film thicker than 3.0 nm, due to onset of island nucleation. Photoluminescence spectra exhibit the splitting of degenerate Ge valence band into heavy hole and light hole bands with a broad direct band gap emission peak around 0.81 eV. Temperature and excitation power dependent emission characteristics have been studied to investigate the mechanism of luminescence quenching at high temperatures and the role of non-radiative recombination centers.

  12. On the origin of strain fluctuation in strained-Si grown on SiGe-on-insulator and SiGe virtual substrates

    SciTech Connect (OSTI)

    Kutsukake, Kentaro; Usami, Noritaka; Ujihara, Toru; Fujiwara, Kozo; Sazaki, Gen; Nakajima, Kazuo [Institute for Materials Research, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai 980-8577 (Japan)

    2004-08-23T23:59:59.000Z

    We investigated the microscopic strain fluctuation in strained-Si grown on SiGe-on-insulator (SGOI) and SiGe virtual substrates, and clarified the origins of the strain fluctuation in the strained-Si film. A periodic strain fluctuation, which reflects a cross-hatch pattern of the substrate, was observed in the sample on the virtual substrate. On the other hand, a featureless strain fluctuation with suppressed amplitude was observed in the sample on SGOI substrate. By analyzing the correlation of the Raman peak positions of the Si-Si modes in strained-Si and SiGe, the dominant mechanism of the strain fluctuation in the strained Si film was found to be the compositional fluctuation in underlying SiGe for the sample on SGOI, and the strain fluctuation reflecting the cross-hatch pattern for the sample on the virtual substrate, respectively.

  13. Growth of high-quality GaAs on Ge/Si{sub 1-x}Ge{sub x} on nanostructured silicon substrates

    SciTech Connect (OSTI)

    Vanamu, G.; Datye, A.K.; Dawson, R.; Zaidi, Saleem H. [Department of Chemical and Nuclear Engineering, University of New Mexico, Albuquerque, New Mexico 87131 (United States) and Center for Micro-Engineered Materials, University of New Mexico, Albuquerque, New Mexico 87131 (United States); Center for High Technology Materials, 1313 Goddard SE, Albuquerque, New Mexico 87106 (United States); Gratings, Inc., 2700 B Broadbent Parkway, NE, Albuquerque, New Mexico 87107 (United States)

    2006-06-19T23:59:59.000Z

    Heteroepitaxial growth of GaAs/Ge/SiGe films on submicrostructured Si substrates is reported. One-dimensional, nanometer-linewidth, submicrometer period features were fabricated in Si substrates using interferometric lithography, reactive ion etching, and wet-chemical etching techniques. The quality of the GaAs layers grown on these structures was investigated using high-resolution x-ray diffraction, transmission electron microscopy, scanning electron microscopy, photoluminescence, and etch pit density measurements. The defect density of GaAs epilayers grown on submicrostructured Si at {approx}6x10{sup 5} cm{sup -2} was two orders of magnitude lower compared with that grown on planar silicon. The optical quality of the GaAs/Ge/SiGe on submicrostructured Si was comparable to that of single crystal GaAs.

  14. IEEE TRANSACTIONS ON DEVICE AND MATERIALS RELIABILITY, VOL. 7, NO. 1, MARCH 2007 181 Impact of Strain or Ge Content on the Threshold

    E-Print Network [OSTI]

    Kumar, M. Jagadesh

    of Strain or Ge Content on the Threshold Voltage of Nanoscale Strained-Si/SiGe Bulk MOSFETs M. Jagadesh--The impact of strain on the threshold voltage of nanoscale strained-Si/SiGe MOSFETs is studied by developing a compact analytical model. Our model includes the effects of strain (Ge mole fraction in SiGe substrate

  15. ecent developments in molecular beam epitaxial growth of group IV semiconductors devices has led to a renewed interest in SiGe heterostructures. This effort is motivated

    E-Print Network [OSTI]

    Abbondandolo, Alberto

    to a renewed interest in SiGe heterostructures. This effort is motivated Rmainly by the goal of integrating Valence and conduction band dispersion around the Gpoint of a double Si/Ge QW system grown on cubic Si. Ge originate from the splitting of the Ge confined light hole bands. Electronic states of Si-Ge based

  16. Blazar Variability and Evolution in the GeV Regime

    E-Print Network [OSTI]

    Tsujimoto, S; Nishijima, K; Kodani, K

    2015-01-01T23:59:59.000Z

    One of the most important problem of the blazar astrophysics is to understand the physical origin of the blazar sequence. In this study, we focus on the GeV gamma-ray variability of blazars and evolution perspective we search the relation between the redshift and the variability amplitude of blazars for each blazar subclass. We analyzed the Fermi-LAT data of the TeV blazars and the bright AGNs (flux $\\geq$ 4$\\times10^{-9}$ cm$^{-2}$s$^{-1}$) selected from the 2LAC (the 2nd LAT AGN catalog) data base. As a result, we found a hint of the correlation between the redshift and the variability amplitude in the FSRQs. Furthermore the BL Lacs which have relatively lower peak frequency of the synchrotron radiation and relatively lower redshift, have a tendency to have a smaller variability amplitude.

  17. Pressure Safety of JLAB 12GeV Upgrade Cryomodule

    SciTech Connect (OSTI)

    Cheng, Gary [JLAB; Wiseman, Mark A. [JLAB; Daly, Ed [JLAB

    2009-11-01T23:59:59.000Z

    This paper reviews pressure safety considerations, per the US Department of Energy (DOE) 10CFR851 Final Rule [1], which are being implemented during construction of the 100 Megavolt Cryomodule (C100 CM) for Jefferson Lab’s 12 GeV Upgrade Project. The C100 CM contains several essential subsystems that require pressure safety measures: piping in the supply and return end cans, piping in the thermal shield and the helium headers, the helium vessel assembly which includes high RRR niobium cavities, the end cans, and the vacuum vessel. Due to the vessel sizes and pressure ranges, applicable national consensus code rules are applied. When national consensus codes are not applicable, equivalent design and fabrication approaches are identified and implemented. Considerations for design, material qualification, fabrication, inspection and examination are summarized. In addition, JLAB’s methodologies for implementation of the 10 CFR 851 requirements are described.

  18. Massive "spin-2" theories in arbitrary $D \\ge 3$ dimensions

    E-Print Network [OSTI]

    D. Dalmazi; A. L. R. dos Santos; E. L. Mendonça

    2014-08-28T23:59:59.000Z

    Here we show that in arbitrary dimensions $D\\ge 3$ there are two families of second order Lagrangians describing massive "spin-2" particles via a nonsymmetric rank-2 tensor. They differ from the usual Fierz-Pauli theory in general. At zero mass one of the families is Weyl invariant. Such massless theory has no particle content in $D=3$ and gives rise, via master action, to a dual higher order (in derivatives) description of massive spin-2 particles in $D=3$ where both the second and the fourth order terms are Weyl invariant, contrary to the linearized New Massive Gravity. However, only the fourth order term is invariant under arbitrary antisymmetric shifts. Consequently, the antisymmetric part of the tensor $e_{[\\mu\

  19. The cross-plane thermoelectric properties of p-Ge/Si{sub 0.5}Ge{sub 0.5} superlattices

    SciTech Connect (OSTI)

    Ferre Llin, L.; Samarelli, A.; Weaver, J. M. R.; Dobson, P. S.; Paul, D. J. [School of Engineering, University of Glasgow, Rankine Building, Oakfield Avenue, Glasgow G12 8LT (United Kingdom)] [School of Engineering, University of Glasgow, Rankine Building, Oakfield Avenue, Glasgow G12 8LT (United Kingdom); Cecchi, S.; Chrastina, D.; Isella, G. [L-NESS, Politecnico di Milano, Via Anzani 42, 22100 Como (Italy)] [L-NESS, Politecnico di Milano, Via Anzani 42, 22100 Como (Italy); Etzelstorfer, T.; Stangl, J. [Institute of Semiconductor and Solid State Physics, Johannes Kepler Universität, Linz (Austria)] [Institute of Semiconductor and Solid State Physics, Johannes Kepler Universität, Linz (Austria); Müller Gubler, E. [Electron Microscopy ETH Zurich, ETH Zurich, Wolfgang-Pauli-Str. 16, CH-8093 Zurich (Switzerland)] [Electron Microscopy ETH Zurich, ETH Zurich, Wolfgang-Pauli-Str. 16, CH-8093 Zurich (Switzerland)

    2013-09-30T23:59:59.000Z

    The electrical conductivity, Seebeck coefficients, and thermal conductivities of a range of p-type Ge/Si{sub 0.5}Ge{sub 0.5} superlattices designed for thermoelectric generation and grown by low energy plasma enhanced chemical vapor deposition have been measured using a range of microfabricated test structures. For samples with barriers around 0.5 nm in thickness, the measured Seebeck coefficients were comparable to bulk p-SiGe at similar doping levels suggesting the holes see the material as a random bulk alloy rather than a superlattice. The Seebeck coefficients for Ge quantum wells of 2.85 ± 0.85 nm increased up to 533 ± 25 ?V/K as the doping was reduced. The thermal conductivities are between 4.5 to 6.0 Wm{sup ?1}K{sup ?1} which are lower than comparably doped bulk Si{sub 0.3}Ge{sub 0.7} but higher than undoped Si/Ge superlattices. The highest measured figure of merit ZT was 0.080 ± 0.011 obtained for the widest quantum well studied. Analysis suggests that interface roughness is presently limiting the performance and a reduction in the strain between the quantum wells and barriers has the potential to improve the thermoelectric performance.

  20. Large-angle production of charged pions by 3 GeV/c - 12 GeV/c protons on carbon, copper and tin targets

    E-Print Network [OSTI]

    HARP Collaboration

    2007-09-21T23:59:59.000Z

    A measurement of the double-differential $\\pi^{\\pm}$ production cross-section in proton--carbon, proton--copper and proton--tin collisions in the range of pion momentum $100 \\MeVc \\leq p < 800 \\MeVc$ and angle $0.35 \\rad \\le \\theta <2.15 \\rad$ is presented. The data were taken with the HARP detector in the T9 beam line of the CERN PS. The pions were produced by proton beams in a momentum range from 3 \\GeVc to 12 \\GeVc hitting a target with a thickness of 5% of a nuclear interaction length. The tracking and identification of the produced particles was done using a small-radius cylindrical time projection chamber (TPC) placed in a solenoidal magnet. An elaborate system of detectors in the beam line ensured the identification of the incident particles. Results are shown for the double-differential cross-sections at four incident proton beam momenta (3 \\GeVc, 5 \\GeVc, 8 \\GeVc and 12 \\GeVc).

  1. Signal modeling of high-purity Ge detectors with a small read-out electrode and application to neutrinoless double beta decay search in Ge-76

    E-Print Network [OSTI]

    M. Agostini; C. A. Ur; D. Budjáš; E. Bellotti; R. Brugnera; C. M. Cattadori; A. di Vacri; A. Garfagnini; L. Pandola; S. Schönert

    2011-01-17T23:59:59.000Z

    The GERDA experiment searches for the neutrinoless double beta decay of Ge-76 using high-purity germanium detectors enriched in Ge-76. The analysis of the signal time structure provides a powerful tool to identify neutrinoless double beta decay events and to discriminate them from gamma-ray induced backgrounds. Enhanced pulse shape discrimination capabilities of "Broad Energy Germanium" detectors with a small read-out electrode have been recently reported. This paper describes the full simulation of the response of such a detector, including the Monte Carlo modeling of radiation interaction and subsequent signal shape calculation. A pulse shape discrimination method based on the ratio between the maximum current signal amplitude and the event energy applied to the simulated data shows quantitative agreement with the experimental data acquired with calibration sources. The simulation has been used to study the survival probabilities of the decays which occur inside the detector volume and are difficult to assess experimentally. Such internal decay events are produced by the cosmogenic radio-isotopes Ge-68 and Co-60 and the neutrinoless double beta decay of Ge-76. Fixing the experimental acceptance of the double escape peak of the 2.614 MeV photon to 90%, the estimated survival probabilities at Qbb = 2.039 MeV are (86+-3)% for Ge-76 neutrinoless double beta decays, (4.5+-0.3)% for the Ge-68 daughter Ga-68, and (0.9+0.4-0.2)% for Co-60 decays.

  2. Antiferromagnetic ordering in NdAuGe compound

    SciTech Connect (OSTI)

    Bashir, A. K. H.; Tchoula Tchokonté, M. B., E-mail: mtchokonte@uwc.ac.za [Department of Physics, University of the Western Cape, Private Bag X17, Bellville 7535 (South Africa); Snyman, J. L.; Sondezi, B. M.; Strydom, A. M. [Department of Physics, University of Johannesburg, Auckland Park 2006 (South Africa)

    2014-05-07T23:59:59.000Z

    The compound NdAuGe was investigated by means of electrical resistivity, ?(T), magnetic susceptibility, ?(T), magnetization, ?(?{sub 0}H), and specific heat, C{sub p}(T), measurements. Powder X-ray diffraction studies confirm a hexagonal LiGaGe-type structure with space group P6{sub 3}mc (No. 186). ?(T) data show normal metallic behaviour and a tendency toward saturation at higher temperatures. The low temperature ?(T) data indicate a phase transition around 3.8?K. The low field dc ?(T) data show an antiferromagnetic anomaly associated with a Néel temperature at T{sub N}?=?3.7?K close to the phase transition observed in ?(T) results. At higher temperatures, ?(T) follows the paramagnetic Curie-Weiss behaviour with an effective magnetic moment ?{sub eff}=3.546(4)??{sub B} and a paramagnetic Weiss temperature of ?{sub p}=?6.1(4)?K. The value obtained for ?{sub eff} is close to the value of 3.62??{sub B} expected for the free Nd{sup 3+}-ion. ?(?{sub 0}H) shows a linear behaviour with applied field up to 3?T with an evidence of metamagnetic behaviour above 3?T. C{sub p}(T) confirms the magnetic phase transition at T{sub N}?=?3.4?K. The 4f-electron specific heat indicates a Schottky-type anomaly around 16.5?K with energy splitting ?{sub 1}=25.8(4) K and ?{sub 2}=50.7(4) K of the Nd{sup 3+}?(J?=?9/2) multiplet, that are associated with, respectively, the first and second excited states of the Nd{sup 3+}-ion.

  3. Thermoelectric properties of high quality nanostructured Ge:Mn thin D. Tanoff2*

    E-Print Network [OSTI]

    Boyer, Edmond

    Thermoelectric properties of high quality nanostructured Ge:Mn thin films D. Taïnoff2* , A. Barski2 nanostructured thin films and the measurement of their thermoelectric properties. We investigate the growth of Ge temperature thermoelectric properties of these layers containing spherical inclusions are discussed regarding

  4. Optical gain from the direct gap transition of Ge-on-Si at room temperature

    E-Print Network [OSTI]

    Liu, Jifeng

    We report direct band gap optical gain of tensile strained n+ epitaxial Ge-on-Si at room temperature, which confirms that band-engineered Ge-on-Si is a promising gain medium for monolithic optical amplifiers and lasers on Si.

  5. FTIR Emission Spectra, Molecular Constants, and Potential Curve of Ground State GeO

    E-Print Network [OSTI]

    Le Roy, Robert J.

    FTIR Emission Spectra, Molecular Constants, and Potential Curve of Ground State GeO Edward G. Lee-resolution FTIR emission spectroscopy measurements for the five common isoto- pomers of GeO are combined­9), photoelectron spectroscopy (10), electronic absorption (11­13), and emission (14) spectroscopy, and in matrix

  6. Donor-vacancy pairs in irradiated n-Ge: A searching look at the problem

    SciTech Connect (OSTI)

    Emtsev, Vadim; Oganesyan, Gagik [IoffePhysicotechnical Institute, Russian Academy of Sciences, Politekhnicheskaya ulitsa 26, 194021 St. Petersburg (Russian Federation)

    2014-02-21T23:59:59.000Z

    The present situation concerning the identification of vacancy-donor pairs in irradiated n-Ge is discussed. The challenging points are the energy states of these defects deduced from DLTS spectra. Hall effect data seem to be at variance with some important conclusions drawn from DLTS measurements. Critical points of the radiation-produced defect modeling in n-Ge are highlighted.

  7. Modern Trend of High-Speed SiGe Heterojunction Bipolar Transistors (HBTs) (Invited Paper)

    E-Print Network [OSTI]

    Rieh, Jae-Sung

    , etc. There certainly exist extra cost for SiGe HBT technology compared to baseline CMOS technology be noted that the cost for the highly expensive phase-shift mask(s) required for CMOS technology to exhibit-gu, Seoul 136-701, Korea jsrieh@korea.ac.kr Abstract SiGe HBT technology has emerged as a strong contender

  8. Understanding Phase Transformation in Crystalline Ge Anodes for Li-Ion Batteries

    E-Print Network [OSTI]

    Cui, Yi

    studies. 1. INTRODUCTION One of the most important renewable energy storage technologies is lithium and § Department of Chemistry, Stanford University, Stanford, California 94305, United States Stanford Synchrotron the beginning stage of lithiation, followed by the conversion of the remaining crystalline Ge to amorphous Ge

  9. Development of SiGe arrays for visible-near IR imaging applications

    E-Print Network [OSTI]

    Sood, Ashok K.

    SiGe based focal plane arrays offer a low cost alternative for developing visible- near-infrared focal plane arrays that will cover the spectral band from 0.4 to 1.6 microns. The attractive features of SiGe based foal plane ...

  10. Development of low dark current SiGe-detector arrays for visible-NIR imaging sensor

    E-Print Network [OSTI]

    Sood, Ashok K.

    SiGe based Focal Plane Arrays offer a low cost alternative for developing visible- NIR focal plane arrays that will cover the spectral band from 0.4 to 1.6 microns. The attractive features of SiGe based IRFPA's will take ...

  11. A 7-decades Tunable Translinear SiGe BiCMOS 3-phase Sinusoidal Oscillator

    E-Print Network [OSTI]

    Cauwenberghs, Gert

    A 7-decades Tunable Translinear SiGe BiCMOS 3-phase Sinusoidal Oscillator Dimitrios N. Loizos 1 of these controls to external current biases. Measurements on a 0.5m SiGe BiCMOS implementation of the architecture

  12. Infrared absorption of n-type tensile-strained Ge-on-Si

    E-Print Network [OSTI]

    Wang, Xiaoxin

    We analyze the IR absorption of tensile-strained, n-type Ge for Si-compatible laser applications. A strong intervalley scattering from the indirect L valleys to the direct ? valley in n[superscript +] Ge-on-Si is reported ...

  13. Activation and thermal stability of ultra-shallow B{sup +}-implants in Ge

    SciTech Connect (OSTI)

    Yates, B. R.; Darby, B. L.; Jones, K. S. [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Petersen, D. H. [DTU Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark); Hansen, O. [DTU Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark); CINF, Center for Individual Nanoparticle Functionality, Technical University of Denmark, DK-2800 Kongens Lyngby (Denmark); Lin, R.; Nielsen, P. F. [CAPRES A/S, Scion-DTU, DK-2800 Kgs. Lyngby (Denmark); Romano, L. [IMM-CNR MATIS and Dipartimento di Fisica e Astronomia, Universita di Catania, Via S. Sofia 64, I-95123 Catania (Italy); Doyle, B. L. [Sandia National Laboratories, MS-1056, Albuquerque, New Mexico 87185 (United States); Kontos, A. [Applied Materials, Gloucester, Massachusetts 01930 (United States)

    2012-12-15T23:59:59.000Z

    The activation and thermal stability of ultra-shallow B{sup +} implants in crystalline (c-Ge) and preamorphized Ge (PA-Ge) following rapid thermal annealing was investigated using micro Hall effect and ion beam analysis techniques. The residual implanted dose of ultra-shallow B{sup +} implants in Ge was characterized using elastic recoil detection and was determined to correlate well with simulations with a dose loss of 23.2%, 21.4%, and 17.6% due to ion backscattering for 2, 4, and 6 keV implants in Ge, respectively. The electrical activation of ultra-shallow B{sup +} implants at 2, 4, and 6 keV to fluences ranging from 5.0 Multiplication-Sign 10{sup 13} to 5.0 Multiplication-Sign 10{sup 15} cm{sup -2} was studied using micro Hall effect measurements after annealing at 400-600 Degree-Sign C for 60 s. For both c-Ge and PA-Ge, a large fraction of the implanted dose is rendered inactive due to the formation of a presumable B-Ge cluster. The B lattice location in samples annealed at 400 Degree-Sign C for 60 s was characterized by channeling analysis with a 650 keV H{sup +} beam by utilizing the {sup 11}B(p, {alpha})2{alpha} nuclear reaction and confirmed the large fraction of off-lattice B for both c-Ge and PA-Ge. Within the investigated annealing range, no significant change in activation was observed. An increase in the fraction of activated dopant was observed with increasing energy which suggests that the surface proximity and the local point defect environment has a strong impact on B activation in Ge. The results suggest the presence of an inactive B-Ge cluster for ultra-shallow implants in both c-Ge and PA-Ge that remains stable upon annealing for temperatures up to 600 Degree-Sign C.

  14. Mn solid solutions in self-assembled Ge/Si (001) quantum dot heterostructures

    SciTech Connect (OSTI)

    Kassim, J.; Nolph, C.; Reinke, P.; Floro, J. [Department of Materials Science and Engineering, University of Virginia, Charlottesville, Virginia 22904 (United States); Jamet, M. [Institut Nanosciences et Cryogenie/SP2M, CEA-UJF, F-38054 Grenoble (France)

    2012-12-10T23:59:59.000Z

    Heteroepitaxial Ge{sub 0.98}Mn{sub 0.02} quantum dots (QDs) on Si (001) were grown by molecular beam epitaxy. The standard Ge wetting layer-hut-dome-superdome sequence was observed, with no indicators of second phase formation in the surface morphology. We show that Mn forms a dilute solid solution in the Ge quantum dot layer, and a significant fraction of the Mn partitions into a sparse array of buried, Mn-enriched silicide precipitates directly underneath a fraction of the Ge superdomes. The magnetic response from the ultra-thin film indicates the absence of robust room temperature ferromagnetism, perhaps due to anomalous intermixing of Si into the Ge quantum dots.

  15. Ohmic contact formation on n-type Ge by direct deposition of TiN

    SciTech Connect (OSTI)

    Iyota, Masatoshi; Yamamoto, Keisuke [Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1 Kasuga-koen, Kasuga, Fukuoka 816-8580 (Japan); Wang, Dong; Yang, Haigui; Nakashima, Hiroshi [Art, Science and Technology Center for Cooperative Research, Kyushu University, 6-1 Kasuga-koen, Kasuga, Fukuoka 816-8580 (Japan)

    2011-05-09T23:59:59.000Z

    We succeeded in Ohmic contact formation on an n-Ge substrate by direct sputter deposition from a TiN target and subsequent postmetallization annealing (PMA) at 350 deg. C. The Schottky barrier heights of the TiN/n-Ge and TiN/p-Ge contacts were 0.18 eV and 0.50 eV, respectively, and were maintained up to a PMA temperature of 550 deg. C. These electrical characteristics are likely to be associated with an approximately 1-nm-thick interlayer formed at a TiN/Ge interface, which leads to the alleviation of the Fermi level pinning. We demonstrated the validity of the TiN/n-Ge contact using an n{sup +}/p junction, which showed an excellent ideal factor of n=1.01.

  16. An ultra-thin buffer layer for Ge epitaxial layers on Si

    SciTech Connect (OSTI)

    Kawano, M.; Yamada, S.; Tanikawa, K.; Miyao, M.; Hamaya, K. [Department of Electronics, Kyushu University, 744 Motooka, Fukuoka 819-0395 (Japan)] [Department of Electronics, Kyushu University, 744 Motooka, Fukuoka 819-0395 (Japan); Sawano, K. [Advanced Research Laboratories, Tokyo City University, 8-15-1 Todoroki, Tokyo 158-0082 (Japan)] [Advanced Research Laboratories, Tokyo City University, 8-15-1 Todoroki, Tokyo 158-0082 (Japan)

    2013-03-25T23:59:59.000Z

    Using an Fe{sub 3}Si insertion layer, we study epitaxial growth of Ge layers on a Si substrate by a low-temperature molecular beam epitaxy technique. When we insert only a 10-nm-thick Fe{sub 3}Si layer in between Si and Ge, epitaxial Ge layers can be obtained on Si. The detailed structural characterizations reveal that a large lattice mismatch of {approx}4% is completely relaxed in the Fe{sub 3}Si layer. This means that the Fe{sub 3}Si layers can become ultra-thin buffer layers for Ge on Si. This method will give a way to realize a universal buffer layer for Ge, GaAs, and related devices on a Si platform.

  17. Modeling of multilayer SiGe based thin film solar cells

    SciTech Connect (OSTI)

    Christoffel, E.; Debarge, L.; Slaoui, A. [CNRS, Strasbourg (France). Lab. PHASE

    1997-12-31T23:59:59.000Z

    Simulations using PC1D have been performed to demonstrate the viability of crystalline SiGe alloys implementation in thin film solar cells. An optimized structure would consist of a p-type doped SiGe layer, capped with a Si p-n junction at the top, and a Si BSF at the bottom. Further refinements in such cell structure include a gradual compositional profile of the SiGe alloy layer. Compared to a conventional Si thin film cell, up to 5% relative efficiency gain is demonstrated, for a 20 {micro}m thick SiGe layer with less than 10% Ge content, p-type doped to more than 1 10{sup 17} cm{sup {minus}3}, and a realistic minority carriers diffusion length of the order of the layer thickness.

  18. Nanoporosity induced by ion implantation in deposited amorphous Ge thin films

    SciTech Connect (OSTI)

    Romano, L.; Impellizzeri, G.; Ruffino, F.; Miritello, M.; Grimaldi, M. G. [IMM-CNR MATIS and Dipartimento di Fisica e Astronomia, Universita di Catania, Via S. Sofia 64, I-95123 Catania (Italy); Bosco, L. [Scuola Superiore di Catania, Via Valdisavoia 9, I-95123 Catania (Italy)

    2012-06-01T23:59:59.000Z

    The formation of a nano-porous structure in amorphous Ge thin film (sputter-deposited on SiO{sub 2}) during ion irradiation at room temperature with 300 keV Ge{sup +} has been observed. The porous film showed a sponge-like structure substantially different from the columnar structure reported for ion implanted bulk Ge. The voids size and structure resulted to be strongly affected by the material preparation, while the volume expansion turned out to be determined only by the nuclear deposition energy. In SiGe alloys, the swelling occurs only if the Ge concentration is above 90%. These findings rely on peculiar characteristics related to the mechanism of voids nucleation and growth, but they are crucial for future applications of active nanostructured layers such as low cost chemical and biochemical sensing devices or electrodes in batteries.

  19. Suppression of structural imperfection in strained Si by utilizing SiGe bulk substrate

    SciTech Connect (OSTI)

    Usami, N.; Nose, Y.; Fujiwara, K.; Nakajima, K. [Institute for Materials Research (IMR), Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)

    2006-05-29T23:59:59.000Z

    We attempted to utilize homemade SiGe bulk crystal as a substrate for epitaxy of strain-controlled heterostructures. X-ray reciprocal space mapping clarified that the growth of a Si thin film on a SiGe bulk substrate leads to reduction in the orientation fluctuation compared with that on a SiGe virtual substrate. Furthermore, analysis of Raman spectra revealed a dramatic decrease of the strain fluctuation in the strained Si film on the SiGe bulk substrate. These results suggest that the SiGe bulk crystal can be utilized as a substrate for various strain-controlled heterostructures for fundamental studies as well as improvement of device performance.

  20. Buffer layers for narrow bandgap a-SiGe solar cells

    SciTech Connect (OSTI)

    Liao, X.B.; Walker, J.; Deng, X.

    1999-07-01T23:59:59.000Z

    In high efficiency narrow bandgap (NBG) a-SiGe solar cells, thin buffer layers of unalloyed hydrogenated amorphous silicon (a-Si) are usually used at the interfaces between the a-SiGe intrinsic layer and the doped layers. They investigated the effect of inserting additional a-SiGe interface layers between these a-Si buffer layers and the a-SiGe absorber layer. They found that such additional interface layers increase solar cell V{sub oc} and FF sizably, most likely due to the reduction or elimination of the abrupt bandgap discontinuity between the a-SiGe absorber layer and the a-Si buffer layers. With these improved narrow bandgap solar cells incorporated into the fabrication of triple-junction a-Si based solar cells, they obtained triple cells with initial efficiency of 10.6%.

  1. HIGH TEMPERATURE LATTICE PARAMETERS OF ZnSiP2, ZnGeP2 AND CdGeP2 A. MILLER (*), R. G. HUMPHREYS and B. CHAPMAN

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    HIGH TEMPERATURE LATTICE PARAMETERS OF ZnSiP2, ZnGeP2 AND CdGeP2 A. MILLER (*), R. G. HUMPHREYS parameters from room temperature to 1.100 "C have been studied for the chalcopyrite semiconductors, ZnSiP2, ZnGeP2 and CdGeP2 using a high temperature X-ray camera. All three compounds show an increase

  2. DOE/CS/34039--Tl

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power Administration wouldDECOMPOSITION OF CALCIUMCOSTDOENuclear1 ofDOE Office of4 Volume

  3. DOE/ET/33011--Tl

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power Administration wouldDECOMPOSITION OF CALCIUMCOSTDOENuclear1382 THE HUMANlviA,'{ ' -

  4. Ultra-high frequency photoconductivity decay in GaAs/Ge/GaAs double heterostructure grown by molecular beam epitaxy

    SciTech Connect (OSTI)

    Hudait, M. K.; Zhu, Y. [Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States)] [Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States); Johnston, S. W. [National Renewable Energy Laboratory, Golden, Colorado 80401 (United States)] [National Renewable Energy Laboratory, Golden, Colorado 80401 (United States); Maurya, D.; Priya, S. [Center for Energy Harvesting Materials and Systems (CEHMS), Virginia Tech, Blacksburg, Virginia 24061 (United States)] [Center for Energy Harvesting Materials and Systems (CEHMS), Virginia Tech, Blacksburg, Virginia 24061 (United States); Umbel, R. [Materials Science and Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States)] [Materials Science and Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States)

    2013-03-04T23:59:59.000Z

    GaAs/Ge/GaAs double heterostructures (DHs) were grown in-situ using two separate molecular beam epitaxy chambers. High-resolution x-ray rocking curve demonstrates a high-quality GaAs/Ge/GaAs heterostructure by observing Pendelloesung oscillations. The kinetics of the carrier recombination in Ge/GaAs DHs were investigated using photoconductivity decay measurements by the incidence excitation from the front and back side of 15 nm GaAs/100 nm Ge/0.5 {mu}m GaAs/(100)GaAs substrate structure. High-minority carrier lifetimes of 1.06-1.17 {mu}s were measured when excited from the front or from the back of the Ge epitaxial layer, suggests equivalent interface quality of GaAs/Ge and Ge/GaAs. Wavelength-dependent minority carrier recombination properties are explained by the wavelength-dependent absorption coefficient of Ge.

  5. FILE CPO-a-.... l~a.yii GE DOCUMENT NO. 80SDS4230 DEVELOPMENT AND DEMONSTRATION

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    FILE CPO¥-a-.... l£~a.yii GE DOCUMENT NO. 80SDS4230 DEVELOPMENT AND DEMONSTRATION OF A 31~STIRLING Government or any agency thereof. #12;GE DOCUMENT NO. 80SDS4230 DEVELOPMENT AND DEMONSTRATION OF STIRLING

  6. High Speed Localized Cooling using SiGe Superlattice Microrefrigerators Yan Zhang, James Christofferson and Ali Shakouri

    E-Print Network [OSTI]

    High Speed Localized Cooling using SiGe Superlattice Microrefrigerators Yan Zhang, James In this paper, thin film based SiGe superlattice microrefrigerators are fabricated and characterized in terms

  7. Millimeter-wave Wafer-Scale Phased Arrays and Wireless Communication Circuits and Systems in SiGe and CMOS Technology

    E-Print Network [OSTI]

    Shin, Woorim

    LRR and SRR systems in SiGe BiC- MOS technology,” IEEEW. Min and G. Rebeiz, “Ka-band SiGe HBT low phase imbalancehigh- performance > 100 GHz SiGe and CMOS circuits,” IEEE

  8. Strain partition of SiSiGe and SiO2 SiGe on compliant substrates Center for Photonics and Optoelectronic Materials and Department of Electrical Engineering,

    E-Print Network [OSTI]

    Duffy, Thomas S.

    of crystalline Si and amorphous SiO2 deposited on crystalline SiGe on a compliant viscous borophosphorosilicate BPSG glass has been observed. Pseudomorphic epitaxial Si was deposited on SiGe films, which were fabricated on BPSG by wafer bonding and the Smart-cut® process. The strains in SiGe and Si films were found

  9. $\\Lambda$(1520)-Produktion in Proton-Proton- und zentralen Blei-Blei-Reaktionen bei 158 GeV pro Nukleon

    E-Print Network [OSTI]

    Markert, C

    2000-01-01T23:59:59.000Z

    $\\Lambda$(1520)-Produktion in Proton-Proton- und zentralen Blei-Blei-Reaktionen bei 158 GeV pro Nukleon

  10. Shower characteristics of particles with momenta from up to 100 GeV in the CALICE Scintillator-Tungsten HCAL

    E-Print Network [OSTI]

    Klempt W

    2015-01-01T23:59:59.000Z

    Shower characteristics of particles with momenta from up to 100 GeV in the CALICE Scintillator-Tungsten HCAL

  11. Study of a-SiGe:H films and nip devices used in high efficiency triple junction solar cells

    E-Print Network [OSTI]

    Deng, Xunming

    Study of a-SiGe:H films and n­i­p devices used in high efficiency triple junction solar cells and n­i­p solar cells for GeH4=Si2H6 ratio varying from 1.43 to 0. This results in a variation of band measurements on n­i­p solar cells with i-layer having different Ge content show that as Ge content increase

  12. Atomic imaging and modeling of passivation, functionalization, and atomic layer deposition nucleation of the SiGe(001) surface via

    E-Print Network [OSTI]

    Kummel, Andrew C.

    nucleation of the SiGe(001) surface via H2O2(g) and trimethylaluminum dosing Tobin Kaufman-Osborn a , Evgueni chemisorbates. XPS and DFT demonstrate that the room temperature H2O2/SiGe surface is composed of only Ge on the surface. STS verifies that the TMA/H2O2/SiGe surface has an unpinned Fermi level with no states

  13. Amorphous Ge quantum dots embedded in SiO{sub 2} formed by low energy ion implantation

    SciTech Connect (OSTI)

    Zhao, J. P. [Texas Center for Superconductivity, University of Houston, Houston, Texas 77204 (United States); Department of Physics, University of Houston, Houston, Texas 77204 (United States); Department of Chemistry, University of Houston, Houston, Texas 77204 (United States); Huang, D. X.; Jacobson, A. J. [Texas Center for Superconductivity, University of Houston, Houston, Texas 77204 (United States); Department of Chemistry, University of Houston, Houston, Texas 77204 (United States); Chen, Z. Y.; Makarenkov, B. [Department of Chemistry, University of Houston, Houston, Texas 77204 (United States); Chu, W. K. [Texas Center for Superconductivity, University of Houston, Houston, Texas 77204 (United States); Department of Physics, University of Houston, Houston, Texas 77204 (United States); Bahrim, B. [Department of Chemistry and Physics, Lamar University, Beaumont, Texas 77710 (United States); Rabalais, J. W. [Department of Chemistry, University of Houston, Houston, Texas 77204 (United States); Department of Chemistry and Physics, Lamar University, Beaumont, Texas 77710 (United States)

    2008-06-15T23:59:59.000Z

    Under ultrahigh vacuum conditions, extremely small Ge nanodots embedded in SiO{sub 2}, i.e., Ge-SiO{sub 2} quantum dot composites, have been formed by ion implantation of {sup 74}Ge{sup +} isotope into (0001) Z-cut quartz at a low kinetic energy of 9 keV using varying implantation temperatures. Transmission electron microscopy (TEM) images and micro-Raman scattering show that amorphous Ge nanodots are formed at all temperatures. The formation of amorphous Ge nanodots is different from reported crystalline Ge nanodot formation by high energy ion implantation followed by a necessary high temperature annealing process. At room temperature, a confined spatial distribution of the amorphous Ge nanodots can be obtained. Ge inward diffusion was found to be significantly enhanced by a synergetic effect of high implantation temperature and preferential sputtering of surface oxygen, which induced a much wider and deeper Ge nanodot distribution at elevated implantation temperature. The bimodal size distribution that is often observed in high energy implantation was not observed in the present study. Cross-sectional TEM observation and the depth profile of Ge atoms in SiO{sub 2} obtained from x-ray photoelectron spectra revealed a critical Ge concentration for observable amorphous nanodot formation. The mechanism of formation of amorphous Ge nanodots and the change in spatial distribution with implantation temperature are discussed.

  14. Photoluminescence from electron-hole plasmas confined in Si/Si 1-,Ge,/Si quantum wells

    E-Print Network [OSTI]

    Photoluminescence from electron-hole plasmas confined in Si/Si 1-,Ge,/Si quantum wells X. Xiao, C 1992) We report the first observation of photoluminescence from electron-hole plasmas in Si/S&,sGe of the physical processes un- derlying luminescence in Si, -,GeX alloys, especially at high carrier densities

  15. Threshold Pressure for Disappearance of Size-Induced Effect in Spinel-Structure Ge3N4 Nanocrystals

    E-Print Network [OSTI]

    Downs, Robert T.

    Threshold Pressure for Disappearance of Size-Induced Effect in Spinel-Structure Ge3N4 Nanocrystals demonstrate that the incompressibility of spinel Ge3N4 nanocrystals decreases when the pressure is elevated above 20 GPa. Ge3N4 nanocrystals initially exhibit a higher bulk modulus of 381(2) GPa. But, above 20

  16. Project #8: Zigang Ge and Robert Guldberg: Cartilage Regeneration with Functional Biomaterials and Quantitative Assessment of Regeneration

    E-Print Network [OSTI]

    Weber, Rodney

    Project #8: Zigang Ge and Robert Guldberg: Cartilage Regeneration with Functional Biomaterials from Georgia Institute of Technology and the GE lab from Peking University. The proposed collaboration the development of effective strategies for functional restoration of degenerated articular joints. Ge's lab

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

    E-Print Network [OSTI]

    Zeng, Li

    2007-01-01T23:59:59.000Z

    Magnetization data for a-Mn 0.15 Ge 0.85 ?lms mea- suredSi 1?x and a-Mn x Ge 1?x samples. . . . . . . . . . . . . .both a-Mn x Si 1?x and a-Mn x Ge 1?x as a func- tion of Mn

  18. A Tunable X-Band SiGe HBT Single Stage Cascode Mustafa DOGAN1,2

    E-Print Network [OSTI]

    Yanikoglu, Berrin

    A Tunable X-Band SiGe HBT Single Stage Cascode LNA Mustafa DOGAN1,2 1 TUBITAK ­ UEKAE, ETTM ­ EMC-band silicon-germanium (SiGe) single stage cascode tunable low-noise amplifier (LNA) for active phased array transmit/receive modules. LNA is implemented by using IHP SiGe heterojunction bipolar transistors (HBTs) 0

  19. Reduced quantum confinement effect and electron-hole separation in SiGe nanowires Michele Amato,1

    E-Print Network [OSTI]

    Marini, Andrea

    Reduced quantum confinement effect and electron-hole separation in SiGe nanowires Michele Amato,1 Using first-principles methods, we investigate the structural and electronic properties of SiGe­26 studies have been carried out to investigate the structural and optoelectronic properties of Si, Ge

  20. Effect of nanodot areal density and period on thermal conductivity in SiGe/Si nanodot superlattices

    E-Print Network [OSTI]

    Haller, Gary L.

    Effect of nanodot areal density and period on thermal conductivity in SiGe/Si nanodot superlattices-plane thermal conductivity in SiGe/Si nanodot superlattices NDSLs . For all ND areal densities considered, we found that in SiGe/Si NDSLs decreased monotonically with decreasing period and reached values lower than

  1. Carrier mobilities and process stability of strained Si n-and p-MOSFETs on SiGe virtual substrates

    E-Print Network [OSTI]

    Carrier mobilities and process stability of strained Si n- and p-MOSFETs on SiGe virtual substrates. INTRODUCTION Since the advent of the relaxed graded buffer technique in 1991,1 SiGe alloys have been a proven path to increasing the functionality of the silicon microelectronics platform. SiGe virtual substrates

  2. Carbon incorporation for strain compensation during solid phase epitaxial recrystallization of SiGe on Si at 500600 C

    E-Print Network [OSTI]

    Florida, University of

    Carbon incorporation for strain compensation during solid phase epitaxial recrystallization of SiGe in the MBE grown SiGe layers prior to regrowth at moderate temperatures 500­700 °C has three main effects­10 and photodetectors.11,12 The addition of germa- nium to silicon allows the resulting SiGe layer to have a reduced

  3. SiGe quantum dot single-hole transistor fabricated by atomic force microscope nanolithography and silicon epitaxial-regrowth

    E-Print Network [OSTI]

    Rokhinson, Leonid

    SiGe quantum dot single-hole transistor fabricated by atomic force microscope nanolithography; published online 10 November 2006 A SiGe quantum dot single-hole transistor passivated by silicon epitaxial are reproducible, in sharp contrast with the noisy and irreproducible I-V characteristics of unpassivated SiGe

  4. A translinear SiGe BiCMOS current-controlled oscillator with 80 Hz800 MHz tuning range

    E-Print Network [OSTI]

    Cauwenberghs, Gert

    A translinear SiGe BiCMOS current-controlled oscillator with 80 Hz­800 MHz tuning range Dimitrios N, as a function of two current biases. Experimental results from a 0.5 lm SiGe BiCMOS chip demonstrate 7 decades. Keywords Current-controlled oscillator Á Translinear circuits Á Amplitude and frequency control Á SiGe Bi

  5. ccsd-00097094,version1-21Sep2006 Electron transport through antidot superlattices in Si/SiGe heterostructures: new

    E-Print Network [OSTI]

    Boyer, Edmond

    ccsd-00097094,version1-21Sep2006 Electron transport through antidot superlattices in Si/SiGe investigated the transport properties in a number of Si/SiGe sam- ples with square antidot latticesAs/AlGaAs and Si/SiGe samples with antidot lattices. In samples with a 600 nm lattice period a new series of well

  6. Device Research Conference, June 2003 SiGe Single-Hole Transistor Fabricated by AFM Oxidation and Epitaxial Regrowth

    E-Print Network [OSTI]

    61st Device Research Conference, June 2003 129 SiGe Single-Hole Transistor Fabricated by AFM-energy patterning process based on AFM lithography (to avoid defects from e-beam and RIE) and Si/SiGe). Single-hole transistor, which is the first reported SiGe quantum device with heterojunction passivation

  7. A New SiGe Base Lateral PNM Schottky Collector Bipolar Transistor on SOI for Non-Saturating

    E-Print Network [OSTI]

    Kumar, M. Jagadesh

    A New SiGe Base Lateral PNM Schottky Collector Bipolar Transistor on SOI for Non-Saturating VLSI Logic Design Abstract- A novel bipolar transistor structure, namely, SiGe base lateral PNM Schottky is presented. Based on our simulation results, we demonstrate for the first time that the proposed SiGe base

  8. Low noise Millimeter-wave and THz Receivers, Imaging Arrays, Switches in Advanced CMOS and SiGe Processes /

    E-Print Network [OSTI]

    Uzunkol, Mehmet

    2013-01-01T23:59:59.000Z

    A Low-NEP 0.32 THz SiGe 4 × 4 Imaging Array Using High-consisting of a SiGe LNA and a detector. . . . . . . (a) LNAstack-up of the 0.18 µm SiGe BiCMOS process (Jazz SBC18H3).

  9. SiGe-free strained Si on insulator by wafer bonding and layer transfer T. A. Langdo,a)

    E-Print Network [OSTI]

    SiGe-free strained Si on insulator by wafer bonding and layer transfer T. A. Langdo,a) M. T. Currie; accepted 4 April 2003 SiGe-free strained Si on insulator substrates were fabricated by wafer bonding even after SiGe layer removal. The strain in the structure is thermally stable during 1000 °C anneals

  10. On the design of a 55 GHz Si/SiGe HBT frequency doubler operating close to f max

    E-Print Network [OSTI]

    On the design of a 55 GHz Si/SiGe HBT frequency doubler operating close to f max S. Bruce, M. Kim. Abstract In this paper we present for the first time experimental results on a frequency doubler using a Si/SiGe GHz, for the Si/SiGe HBT, the conversion efficiency in a not completely optimised circuit was found

  11. Transient response of thin film SiGe micro coolers Alberto Fitting, James Christofferson, Xiofeng Fan, Gehong Zeng,

    E-Print Network [OSTI]

    Transient response of thin film SiGe micro coolers Alberto Fitting, James Christofferson, Xiofeng The transient response of thin film SiGe micro coolers is measured using a thremoreflectance technique. Response are used in many of these applications. Several features of thin film SiGe micro coolers give them

  12. Analysis and understanding of unique cryogenic phenomena in state-of-the-art SiGe HBTs

    E-Print Network [OSTI]

    Rieh, Jae-Sung

    Analysis and understanding of unique cryogenic phenomena in state-of-the-art SiGe HBTs Qingqing.E. Thompson Abstract A group of novel device phenomena are reported in state-of-the-art SiGe HBTs operating are observed in the forced-IB output characteristics of 350 GHz SiGe HBTs at cryogenic temperatures. Unlike

  13. Pure spin currents induced by spin-dependent scattering processes in SiGe quantum well structures

    E-Print Network [OSTI]

    Ganichev, Sergey

    Pure spin currents induced by spin-dependent scattering processes in SiGe quantum well structures S-down subbands yielding a pure spin current. In our experiments on SiGe heterostructures the pure spin current recent results obtained on nonmag- netic SiGe nanostructures applying electron spin resonance3,4 ESR

  14. Materials Science and Engineering A 491 (2008) 343348 Composition and microhardness of SiGe solid solution precipitates

    E-Print Network [OSTI]

    Regel, Liya L.

    2008-01-01T23:59:59.000Z

    Materials Science and Engineering A 491 (2008) 343­348 Composition and microhardness of Si­Ge solid solution precipitates in Al­Si­Ge alloys solidified during centrifugation V.N. Gurina,, S.P. Nikanorova, L, the Knoop microhardness of the precipitates and of the matrix of Al­Si­Ge alloys solidified during

  15. Cluster expansion and optimization of thermal conductivity in SiGe nanowires M. K. Y. Chan,1,2

    E-Print Network [OSTI]

    Ceder, Gerbrand

    Cluster expansion and optimization of thermal conductivity in SiGe nanowires M. K. Y. Chan,1,2 J.20.dh, 63.22.Gh, 65.80. g I. INTRODUCTION A. SiGe nanowires for thermoelectric applications Minimizing for thermoelectric applications. Bulk SiGe alloys have been used for thermoelectric power generation for several de

  16. Single-electron quantum dot in Si/SiGe with integrated charge sensing C. B. Simmons,a

    E-Print Network [OSTI]

    Coppersmith, Susan N.

    Single-electron quantum dot in Si/SiGe with integrated charge sensing C. B. Simmons,a Madhu that are important for quantum information processing. Si/SiGe is of interest for semiconductor spin qubits and measurement of a top-gated quantum dot occupied by a single electron in a Si/SiGe heterostructure. Transport

  17. Relaxed SiGe-on-insulator fabricated via wafer bonding and etch back Gianni Taraschi,a)

    E-Print Network [OSTI]

    Relaxed SiGe-on-insulator fabricated via wafer bonding and etch back Gianni Taraschi,a) Thomas A 02139 Received 13 April 2001; accepted 30 January 2002 Relaxed SiGe-on-insulator SGOI was fabricated using a bond/etch-back process. Ultrahigh-vacuum chemical vapor deposition was used to grow a SiGe

  18. Ultrathin Strained Si-on-Insulator and SiGe-on-Insulator Created using Low Temperature Wafer Bonding

    E-Print Network [OSTI]

    Ultrathin Strained Si-on-Insulator and SiGe-on-Insulator Created using Low Temperature Wafer, uniform thickness, low defect density, monocrystalline SiGe alloys and strained Si on any desired substrate was developed, allowing for the creation of SiGe-on-insulator and strained Si-on-insulator. After

  19. Tunable, long-wavelength PtSi/SiGe/Si Schottky diode infrared detectors J. R. Jimeneza)

    E-Print Network [OSTI]

    Tunable, long-wavelength PtSi/SiGe/Si Schottky diode infrared detectors J. R. Jimeneza) Faura, Massachusetts 01731 Received 9 March 1995; accepted for publication 31 May 1995 We have fabricated p-type PtSi/SiGe dependent on the applied bias. The variability in the barrier height is obtained by using the SiGe

  20. Tuning the properties of Ge-quantum dots superlattices in amorphous silica matrix through deposition conditions

    SciTech Connect (OSTI)

    Pinto, S. R. C.; Ramos, M. M. D.; Gomes, M. J. M. [University of Minho, Centre of Physics and Physics Department, Braga 4710-057 (Portugal); Buljan, M. [Ruder Boskovic Institute, Bijenicka cesta 54, Zagreb 10000 (Croatia); Chahboun, A. [University of Minho, Centre of Physics and Physics Department, Braga 4710-057 (Portugal); Physics Department, FST Tanger, Tanger BP 416 (Morocco); Roldan, M. A.; Molina, S. I. [Departamento de Ciencia de los Materiales e Ing. Metalurgica y Q. I., Universidad de Cadiz, Cadiz (Spain); Bernstorff, S. [Sincrotrone Trieste, SS 14 km163, 5, Basovizza 34012 (Italy); Varela, M.; Pennycook, S. J. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Barradas, N. P.; Alves, E. [Instituto Superior Tecnico e Instituto Tecnologico e Nuclear-, EN10, Sacavem 2686-953 (Portugal)

    2012-04-01T23:59:59.000Z

    In this work, we investigate the structural properties of Ge quantum dot lattices in amorphous silica matrix, prepared by low-temperature magnetron sputtering deposition of (Ge+SiO{sub 2})/SiO{sub 2} multilayers. The dependence of quantum dot shape, size, separation, and arrangement type on the Ge-rich (Ge + SiO{sub 2}) layer thickness is studied. We show that the quantum dots are elongated along the growth direction, perpendicular to the multilayer surface. The size of the quantum dots and their separation along the growth direction can be tuned by changing the Ge-rich layer thickness. The average value of the quantum dots size along the lateral (in-plane) direction along with their lateral separation is not affected by the thickness of the Ge-rich layer. However, the thickness of the Ge-rich layer significantly affects the quantum dot ordering. In addition, we investigate the dependence of the multilayer average atomic composition and also the quantum dot crystalline quality on the deposition parameters.

  1. Tuning the properties of Ge-quantum dots superlattices in amorphous silica matrix through deposition conditions

    SciTech Connect (OSTI)

    Pinto, S. [University of Minho, Portugal; Roldan Gutierrez, Manuel A [ORNL; Ramos, M. M.D. [University of Minho, Portugal; Gomes, M.J.M. [University of Minho, Portugal; Molina, S. I. [Universidad de Cadiz, Spain; Pennycook, Stephen J [ORNL; Varela del Arco, Maria [ORNL; Buljan, M. [R. Boskovic Institute, Zagreb, Croatia; Barradas, N. [Instituto Tecnologico e Nuclear (ITN), Lisbon, Portugal; Alves, E. [Instituto Tecnologico e Nuclear (ITN), Lisbon, Portugal; Chahboun, A. [FST Tanger, Morocco; Bernstorff, S. [Sincrotrone Trieste, Basovizza, Italy

    2012-01-01T23:59:59.000Z

    In this work, we investigate the structural properties of Ge quantum dot lattices in amorphous silica matrix, prepared by low-temperature magnetron sputtering deposition of (Ge+SiO{sub 2})/SiO{sub 2} multilayers. The dependence of quantum dot shape, size, separation, and arrangement type on the Ge-rich (Ge + SiO{sub 2}) layer thickness is studied. We show that the quantum dots are elongated along the growth direction, perpendicular to the multilayer surface. The size of the quantum dots and their separation along the growth direction can be tuned by changing the Ge-rich layer thickness. The average value of the quantum dots size along the lateral (in-plane) direction along with their lateral separation is not affected by the thickness of the Ge-rich layer. However, the thickness of the Ge-rich layer significantly affects the quantum dot ordering. In addition, we investigate the dependence of the multilayer average atomic composition and also the quantum dot crystalline quality on the deposition parameters.

  2. Density functional theory calculations of stability and diffusion mechanisms of impurity atoms in Ge crystals

    SciTech Connect (OSTI)

    Maeta, Takahiro [Graduate School of System Engineering, Okayama Prefectural University, 111 Kuboki, Soja, Okayama 719-1197 (Japan); GlobalWafers Japan Co., Ltd., Higashikou, Seirou-machi, Kitakanbara-gun, Niigata 957-0197 (Japan); Sueoka, Koji [Department of Communication Engineering, Okayama Prefectural University, 111 Kuboki, Soja, Okayama 719-1197 (Japan)

    2014-08-21T23:59:59.000Z

    Ge-based substrates are being developed for applications in advanced nano-electronic devices because of their higher intrinsic carrier mobility than Si. The stability and diffusion mechanism of impurity atoms in Ge are not well known in contrast to those of Si. Systematic studies of the stable sites of 2nd to 6th row element impurity atoms in Ge crystal were undertaken with density functional theory (DFT) and compared with those in Si crystal. It was found that most of the impurity atoms in Ge were stable at substitutional sites, while transition metals in Si were stable at interstitial sites and the other impurity atoms in Si were stable at substitutional sites. Furthermore, DFT calculations were carried out to clarify the mechanism responsible for the diffusion of impurity atoms in Ge crystals. The diffusion mechanism for 3d transition metals in Ge was found to be an interstitial-substitutional diffusion mechanism, while in Si this was an interstitial diffusion mechanism. The diffusion barriers in the proposed diffusion mechanisms in Ge and Si were quantitatively verified by comparing them to the experimental values in the literature.

  3. Development of high-efficiency GaAs solar cells on polycrystalline Ge substrates

    SciTech Connect (OSTI)

    Venkatasubramanian, R.; OQuinn, B.; Hills, J.; Malta, D.; Timmons, M.L.; Hutchby, J.A. [Research Triangle Institute, Research Triangle Park, North Carolina 27709 (United States); Ahrenkiel, R.; Keyes, B.M. [National Renewable Energy Laboratory, Golden, Colorado 80401 (United States)

    1996-01-01T23:59:59.000Z

    Progress in the development of high-efficiency GaAs solar cells on low-cost, large-area, large-grain, optical-grade polycrystalline Ge substrates is described in this paper. First, we present results on the growth of specular GaAs-AlGaAs layers, across the various crystalline orientations of a polycrystalline Ge substrate, by metallorganic chemical vapor deposition (MOCVD). Second, we present the preliminary optimization of minority-carrier properties of GaAs-AlGaAs structures on poly-Ge substrates towards the improvement of GaAs solar cells. We have demonstrated comparable minority-carrier lifetimes in GaAs double-hetero structures grown on optical-grade poly-Ge substrates and electronic-grade single-crystal Ge substrates. In addition, we describe device-structure optimization that have led us to achieve a open-circuit voltage of {approximately}1 Volt in a GaAs solar cell on poly-Ge and to improve our previous best efficiency from 15.8{percent} for a 1-cm{sup 2}-area GaAs cell to 16.7{percent} for a 4-cm{sup 2}-area GaAs solar cell on poly-Ge. {copyright} {ital 1996 American Institute of Physics.}

  4. Hydrogen interaction kinetics of Ge dangling bonds at the Si{sub 0.25}Ge{sub 0.75}/SiO{sub 2} interface

    SciTech Connect (OSTI)

    Stesmans, A., E-mail: andre.stesmans@fys.kuleuven.be; Nguyen Hoang, T.; Afanas'ev, V. V. [Semiconductor Physics Laboratory, Department of Physics and Astronomy, University of Leuven, 3001 Leuven (Belgium)

    2014-07-28T23:59:59.000Z

    The hydrogen interaction kinetics of the GeP{sub b1} defect, previously identified by electron spin resonance (ESR) as an interfacial Ge dangling bond (DB) defect occurring in densities ?7?×?10{sup 12}?cm{sup ?2} at the SiGe/SiO{sub 2} interfaces of condensation grown (100)Si/a-SiO{sub 2}/Ge{sub 0.75}Si{sub 0.25}/a-SiO{sub 2} structures, has been studied as function of temperature. This has been carried out, both in the isothermal and isochronal mode, through defect monitoring by capacitance-voltage measurements in conjunction with ESR probing, where it has previously been demonstrated the defects to operate as negative charge traps. The work entails a full interaction cycle study, comprised of analysis of both defect passivation (pictured as GeP{sub b1}-H formation) in molecular hydrogen (?1?atm) and reactivation (GeP{sub b1}-H dissociation) in vacuum. It is found that both processes can be suitably described separately by the generalized simple thermal (GST) model, embodying a first order interaction kinetics description based on the basic chemical reactions GeP{sub b1}?+?H{sub 2}???GeP{sub b1}H?+?H and GeP{sub b1}H???GeP{sub b1}?+?H, which are found to be characterized by the average activation energies E{sub f}?=?1.44?±?0.04?eV and E{sub d}?=?2.23?±?0.04?eV, and attendant, assumedly Gaussian, spreads ?E{sub f}?=?0.20?±?0.02?eV and ?E{sub d}?=?0.15?±?0.02?eV, respectively. The substantial spreads refer to enhanced interfacial disorder. Combination of the separately inferred kinetic parameters for passivation and dissociation results in the unified realistic GST description that incorporates the simultaneous competing action of passivation and dissociation, and which is found to excellently account for the full cycle data. For process times t{sub a}???35?min, it is found that even for the optimum treatment temperature ?380?°C, only ?60% of the GeP{sub b1} system can be electrically silenced, still far remote from device grade level. This ineffectiveness is concluded, for the major part, to be a direct consequence of the excessive spreads in the activation energies, ?2–3 times larger than for the Si DB P{sub b} defects at the standard thermal (111)Si/SiO{sub 2} interface which may be easily passivated to device grade levels, strengthened by the reduced difference between the average E{sub f} and E{sub d} values. Exploring the guidelines of the GST model indicates that passivation can be improved by decreasing T{sub an} and attendant enlarging of t{sub a}, however, at best still leaving ?2% defects unpassivated even for unrealistically extended anneal times. The average dissociation energy E{sub d}???2.23?eV, concluded as representing the GeP{sub b1}-H bond strength, is found to be smaller than the SiP{sub b}-H one, characterized by E{sub d}???2.83?eV. An energy deficiency is encountered regarding the energy sum rule inherent to the GST-model, the origin of which is substantiated to lie with a more complex nature of the forward passivation process than basically depicted in the GST model. The results are discussed within the context of theoretical considerations on the passivation of interfacial Ge DBs by hydrogen.

  5. Growth and properties of AlGaInP resonant cavity light emitting diodes on Ge/SiGe/Si substrates

    SciTech Connect (OSTI)

    Kwon, O.; Boeckl, J.; Lee, M.L.; Pitera, A.J.; Fitzgerald, E.A.; Ringel, S.A. [Department of Electrical Engineering, Ohio State University, Columbus, Ohio 43210 (United States); Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Department of Electrical and Computer Engineering, Ohio State University, 2015 Neil Avenue, Columbus, Ohio 43210 (United States)

    2005-02-01T23:59:59.000Z

    Visible AlGaInP resonant cavity light emitting diodes (RCLEDs) were grown by molecular beam epitaxy and fabricated on low-dislocation density, SiGe/Si metamorphic substrates. A comparison with identical devices grown on GaAs and Ge substrates shows that not only did the RCLED device structure successfully transfer to the SiGe/Si substrate, but also a higher optical output power was obtained. This result is attributed to enhanced lateral current spreading by the low residual dislocation density ({approx}1x10{sup 6} cm{sup -2}) network within the virtual Ge substrate and the superior thermal conductivity of the underlying Si wafer. In addition, the growth of an AlGaAs current spreading layer and a modified top metal contact were incorporated in the RCLED on SiGe to optimize device performance. The measured electroluminescent output power was 166 {mu}W at a 665 nm peak wavelength under 500 mA current injection. Extremely narrow electroluminescence linewidths were achieved with a full width half maximum value of 3.63 nm under 50 mA current injection. These results demonstrate great promise for the monolithic integration of visible band optical sources with Si-based electronic circuitry.

  6. Potential improvements in SiGe radioisotope thermoelectric generator performance

    SciTech Connect (OSTI)

    Mowery, A.L. [4 Myrtle Bank Lane, Hilton Head Island, South Carolina, 29926-2650 (United States)

    1999-01-01T23:59:59.000Z

    In accordance with NASA{close_quote}s slogan: {open_quotes}Better, Cheaper, Faster,{close_quotes} this paper will address potential improvements to SiGe RTG technology to make them Better. RTGs are doubtless cheaper than {open_quotes}paper designs{close_quotes} which are better and cheaper until development, performance and safety test costs are considered. RTGs have the advantage of being fully developed and tested in the rigors of space for over twenty years. Further, unless a new system can be accelerated tested, as were the RTGs, they cannot be deployed reliably unless a number of systems have succeeded for test periods exceeding the mission lifetime. Two potential developments are discussed that can improve the basic RTG performance by 10 to 40{sup +}{percent} depending on the mission profile. These improvements could be demonstrated in years. Accelerated testing could also be performed in this period to preserve existing RTG reliability. Data from a qualification tested RTG will be displayed, while not definitive, to support the conclusions. Finally, it is anticipated that other investigators will be encouraged to suggest further modifications to the basic RTG design to improve its performance. {copyright} {ital 1999 American Institute of Physics.}

  7. Bottomonium and Drell-Yan production in p-A collisions at 450 GeV

    E-Print Network [OSTI]

    NA50 Collaboration

    2006-03-23T23:59:59.000Z

    The NA50 Collaboration has measured heavy-quarkonium production in p-A collisions at 450 GeV incident energy (sqrt(s) = 29.1 GeV). We report here results on the production of the Upsilon states and of high-mass Drell-Yan muon pairs (m > 6 GeV). The cross-section at midrapidity and the A-dependence of the measured yields are determined and compared with the results of other fixed-target experiments and with the available theoretical estimates. Finally, we also address some issues concerning the transverse momentum distributions of the measured dimuons.

  8. Electroluminescence from Strained Ge membranes and Implications for an Efficient Si-Compatible Laser

    E-Print Network [OSTI]

    Nam, Donguk; Cheng, Szu-Lin; Roy, Arunanshu; Huang, Kevin Chih-Yao; Brongersma, Mark; Nishi, Yoshio; Saraswat, Krishna

    2012-01-01T23:59:59.000Z

    We demonstrate room-temperature electroluminescence (EL) from light-emitting diodes (LED) on highly strained germanium (Ge) membranes. An external stressor technique was employed to introduce a 0.76% bi-axial tensile strain in the active region of a vertical PN junction. Electrical measurements show an on-off ratio increase of one order of magnitude in membrane LEDs compared to bulk. The EL spectrum from the 0.76% strained Ge LED shows a 100nm redshift of the center wavelength because of the strain-induced direct band gap reduction. Finally, using tight-binding and FDTD simulations, we discuss the implications for highly efficient Ge lasers.

  9. Evaluation of Two SiGe HBT Technologies for the ATLAS sLHC Upgrade

    E-Print Network [OSTI]

    Ullán, M

    2008-01-01T23:59:59.000Z

    As previously reported, silicon-germanium (SiGe) heterojunction bipolar transistor (HBT) technologies promise several advantages over CMOS for the front-end readout electronics for the ATLAS upgrade. Since our last paper, we have evaluated the relative merits of the latest generations of IBM SiGe HBT BiCMOS technologies, the 8WL and 8HP platforms. These 130nm SiGe technologies show promise to operate at lower power than CMOS technologies and would provide a viable alternative for the Silicon Strip Detector and Liquid Argon Calorimeter upgrades, provided that the radiation tolerance studies at multiple gamma and neutron irradiation levels, included in this in

  10. Straining of SiGe ultrathin films with mesoporous Si substrates

    SciTech Connect (OSTI)

    Boucherif, A.; Guillot, G.; Lysenko, V. [Institut des Nanotechnologies de Lyon INL-UMR5270, CNRS, INSA de Lyon, Universite de Lyon, Villeurbanne F-69621 (France); Blanchard, N. P.; Regreny, P.; Grenet, G. [Institut des Nanotechnologies de Lyon INL-UMR5270, CNRS, Ecole Centrale de Lyon, Universite de Lyon, Ecully F-69134 (France); Marty, O. [Institut des Nanotechnologies de Lyon INL-UMR5270, CNRS, Universite Lyon 1, Universite de Lyon, Villeurbanne F-69622 (France)

    2010-09-27T23:59:59.000Z

    We report on the fabrication and characterization of ultrathin (down to 50 nm) tensile strained SiGe films on mesoporous Si substrates. Low temperature oxidation of the porous substrate relaxes the compressive strain in the as grown monocrystalline (mc) SiGe. Applying this method to a 50 nm thick mc-Si{sub 0.72}Ge{sub 0.28} film, a tensile strain >0.78% can be achieved without compromising crystalline quality and up to 1.45 % without the appearance of cracks.

  11. Radiation damage of SiGe HBT Technologies at different bias configurations

    E-Print Network [OSTI]

    Ullán, M; Lozano, M; Pellegrini, G; Knoll, D; Heinemann, B

    2008-01-01T23:59:59.000Z

    SiGe BiCMOS technologies are being proposed for the Front-end readout of the detectors in the middle region of the ATLAS-Upgrade. The radiation hardness of the SiGe bipolar transistors is being assessed for this application through irradiations with different particles. Biasing conditions during irradiation of bipolar transistors or circuits have an influence on the damage and there is a risk of erroneous results. We have performed several irradiation experiments of SiGe devices from IHP in different bias conditions. We have observed a systematic trend in gamma irradiations, showing a smaller damage in transistors irradiated biased compared to shorted or floating terminals.

  12. Excitation wavelength dependent photoluminescence in structurally non-uniform Si/SiGe-island heteroepitxial multilayers

    SciTech Connect (OSTI)

    Modi, N.; Tsybeskov, L. [Department of Electrical and Computer Engineering, New Jersey Institute of Technology, Newark, New Jersey 07102 (United States); Lockwood, D. J.; Wu, X.; Baribeau, J.-M. [Institute for Microstructural Sciences, National Research Council, Ottawa, Ontario K1A 0R6 (Canada)

    2012-06-01T23:59:59.000Z

    In nanometer-size Si/SiGe-island heteroepitxial multilayers grown on Si(001), low temperature photoluminescence spectra are observed that strongly depend on the excitation wavelength and show a strong correlation with structural properties revealed by transmission electron microscopy. These experimental results can be explained by assuming that the optically created carriers are strongly localized at Si/SiGe island heterointerfaces. We show that electron-hole pairs are generated and recombine within spatial regions mainly defined by the photoexcitation penetration depth, and that the estimated exciton diffusion length is notably short and comparable with the SiGe-island average size.

  13. Characterization of SiGe/Si multi-quantum wells for infrared sensing

    SciTech Connect (OSTI)

    Moeen, M.; Salemi, A.; Östling, M.; Radamson, H. H., E-mail: rad@kth.se [School of Information and Communication Technology, KTH Royal Institute of Technology, Stockholm, 16640 Kista (Sweden); Kolahdouz, M. [School of Electrical and Computer Engineering, University of Tehran, Tehran (Iran, Islamic Republic of)] [School of Electrical and Computer Engineering, University of Tehran, Tehran (Iran, Islamic Republic of)

    2013-12-16T23:59:59.000Z

    SiGe epitaxial layers are integrated as an active part in thermal detectors. To improve their performance, deeper understanding of design parameters, such as thickness, well periodicity, quality, and strain amount, of the layers/interfaces is required. Oxygen (2–2500?×?10{sup ?9}?Torr) was exposed prior or during epitaxy of SiGe/Si multilayers. In this range, samples with 10?nTorr oxygen were processed to investigate layer quality and noise measurements. Temperature coefficient of resistance was also measured to evaluate the thermal response. These results demonstrate sensitivity of SiGe-based devices to size and location of defects in the structure.

  14. Bottomonium and Drell-Yan production in p-A collisions at 450 GeV

    E-Print Network [OSTI]

    Alessandro, B; Arnaldi, R; Atayan, M; Beolè, S; Boldea, V; Bordalo, P; Borges, G; Castor, J; Chaurand, B; Cheynis, B; Chiavassa, E; Cicalò, C; Comets, M P; Constantinescu, S; Cortese, P; De Falco, A; De Marco, N; Dellacasa, G; Devaux, A; Dita, S; Fargeix, J; Force, P; Gallio, M; Gerschel, C; Giubellino, P; Golubeva, M B; Grigorian, A A; Grossiord, J Y; Guber, F F; Guichard, A; Gulkanian, H R; Idzik, M; Jouan, D; Karavicheva, T L; Kluberg, L; Kurepin, A B; Le Bornec, Y; Lourenço, C; MacCormick, M; Marzari-Chiesa, A; Masera, M; Masoni, A; Monteno, M; Musso, A; Petiau, P; Piccotti, A; Pizzi, J R; Prino, F; Puddu, G; Quintans, C; Ramello, L; Ramos, S; Riccati, L; Santos, H; Saturnini, P; Scomparin, E; Serci, S; Shahoyan, R; Sitta, M; Sonderegger, P; Tarrago, X; Topilskaya, N S; Usai, G L; Vercellin, E; Willis, N

    2006-01-01T23:59:59.000Z

    The NA50 Collaboration has measured heavy-quarkonium production in p-A collisions at 450 GeV incident energy (sqrt(s) = 29.1 GeV). We report here results on the production of the Upsilon states and of high-mass Drell-Yan muon pairs (m > 6 GeV). The cross-section at midrapidity and the A-dependence of the measured yields are determined and compared with the results of other fixed-target experiments and with the available theoretical estimates. Finally, we also address some issues concerning the transverse momentum distributions of the measured dimuons.

  15. Early Commissioning Experience and Future Plans for the 12 GeV Continuous Electron Beam Accelerator Facility

    SciTech Connect (OSTI)

    Spata, Michael F. [JLAB

    2014-12-01T23:59:59.000Z

    Jefferson Lab has recently completed the accelerator portion of the 12 GeV Upgrade for the Continuous Electron Beam Accelerator Facility. All 52 SRF cryomodules have been commissioned and operated with beam. The initial beam transport goals of demonstrating 2.2 GeV per pass, greater than 6 GeV in 3 passes to an existing experimental facility and greater than 10 GeV in 5-1/2 passes have all been accomplished. These results along with future plans to commission the remaining beamlines and to increase the performance of the accelerator to achieve reliable, robust and efficient operations at 12 GeV are presented.

  16. Mid-Infrared Plasmonic Platform based on Heavily Doped Epitaxial Ge-on-Si: Retrieving the Optical Constants of Thin Ge Epilayers

    E-Print Network [OSTI]

    Baldassarre, Leonetta; Samarelli, Antonio; Gallacher, Kevin; Paul, Douglas J; Frigerio, Jacopo; Isella, Giovanni; Sakat, Emilie; Finazzi, Marco; Biagioni, Paolo; Ortolani, Michele

    2015-01-01T23:59:59.000Z

    The n-type Ge-on-Si epitaxial material platform enables a novel paradigm for plasmonics in the mid-infrared, prompting the future development of lab-on-a-chip and subwavelength vibrational spectroscopic sensors. In order to exploit this material, through proper electrodynamic design, it is mandatory to retrieve the dielectric constants of the thin Ge epilayers with high precision due to the difference from bulk Ge crystals. Here we discuss the procedure we have employed to extract the real and imaginary part of the dielectric constants from normal incidence reflectance measurements, by combining the standard multilayer fitting procedure based on the Drude model with Kramers-Kronig transformations of absolute reflectance data in the zero-transmission range of the thin film.

  17. Effects of the lateral ordering of self-assembled SiGe nanoislands grown on strained Si{sub 1-x}Ge{sub x} buffer layers

    SciTech Connect (OSTI)

    Strelchuk, V. V.; Nikolenko, A. S., E-mail: nikolenko_mail@ukr.net; Lytvyn, P. M.; Kladko, V. P.; Gudymenko, A. I.; Valakh, M. Ya. [National Academy of Sciences of Ukraine, V. Lashkaryov Institute of Semiconductor Physics (Ukraine); Krasilnik, Z. F.; Lobanov, D. N.; Novikov, A. V. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation)

    2012-05-15T23:59:59.000Z

    Atomic-force microscopy, micro-Raman spectroscopy, and high resolution X-ray diffraction are applied to study the spatial ordering in single layers of SiGe nanoislands grown on a strained Si{sub 1-x}Ge{sub x} buffer sublayer. It is shown that, apart from stimulating the spatial ordering of nanoislands, the introduction of a Si{sub 1-x}Ge{sub x} sublayer leads to an enhanced role for interdiffusion processes. An unusually high increase in the volume of nanoislands in the process of the epitaxy is related to the anomalously strong diffusion from the buffer sublayer into the islands that is induced by nonuniform fields of elastic strains. The anisotropy of the islands shape and spatial ordering is discussed in terms of the anisotropy of the diffusion processes in spatially nonuniform fields of elastic strains.

  18. Thermoelectric infrared microsensors based on a periodically suspended thermopile integrating nanostructured Ge/SiGe quantum dots superlattice

    SciTech Connect (OSTI)

    Ziouche, K., E-mail: katir.ziouche@iemn.univ-lille1.fr, E-mail: Zahia.bougrioua@iemn.univ-lille1.fr; Bougrioua, Z., E-mail: katir.ziouche@iemn.univ-lille1.fr, E-mail: Zahia.bougrioua@iemn.univ-lille1.fr; Lejeune, P.; Lasri, T.; Leclercq, D. [IEMN, Institute of Electronics, Microelectronics and Nanotechnology, CNRS and Lille 1 University, F-59652 Villeneuve d'Ascq (France); Savelli, G.; Hauser, D.; Michon, P.-M. [CEA, LITEN, Thermoelectricity Laboratory, F-38054 Grenoble (France)

    2014-07-28T23:59:59.000Z

    This paper presents an original integration of polycrystalline SiGe-based quantum dots superlattices (QDSL) into Thermoelectric (TE) planar infrared microsensors (?SIR) fabricated using a CMOS technology. The nanostructuration in QDSL results into a considerably reduced thermal conductivity by a factor up to 10 compared to the one of standard polysilicon layers that are usually used for IR sensor applications. A presentation of several TE layers, QDSL and polysilicon, is given before to describe the fabrication of the thermopile-based sensors. The theoretical values of the sensitivity to irradiance of ?SIR can be predicted thanks to an analytical model. These findings are used to interpret the experimental measurements versus the nature of the TE layer exploited in the devices. The use of nanostructured QDSL as the main material in ?SIR thermopile has brought a sensitivity improvement of about 28% consistent with theoretical predictions. The impact of QDSL low thermal conductivity is damped by the contribution of the thermal conductivity of all the other sub-layers that build up the device.

  19. Effects of boron dopants of Si (001) substrates on formation of Ge layers by sputter epitaxy method

    SciTech Connect (OSTI)

    Tsukamoto, Takahiro; Suda, Yoshiyuki [Graduate School of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588 (Japan)] [Graduate School of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588 (Japan); Hirose, Nobumitsu; Kasamatsu, Akifumi; Mimura, Takashi; Matsui, Toshiaki [National Institute of Information and Communications Technology, 4-2-1 Nukui-Kitamachi, Koganei, Tokyo 184-8795 (Japan)] [National Institute of Information and Communications Technology, 4-2-1 Nukui-Kitamachi, Koganei, Tokyo 184-8795 (Japan)

    2013-10-21T23:59:59.000Z

    The formation of Ge layers on boron-doped Si (001) substrates by our sputter epitaxy method has been investigated. The surface morphology of Ge layers grown on Si substrates depends on the substrate resistance, and flat Ge layers are obtained on Si substrates with 0.015 ? cm resistivity. Highly boron-doped Si substrates cause a transition in the dislocation structure from complex dislocations with 60° dislocation glide planes to 90° pure-edge dislocations, resulting in the formation of flat Ge layers. Furthermore, we have found that the surface morphology of the Ge layers improves with increasing Ge layer thickness. Ge atoms migrating on the deposited Ge layers tend to position themselves at the reactive sites, where the reactivity is related to the number of bonding contacts between the Ge atom and the surface. This modifies the surface morphology, resulting in a flatter surface. Boron dopants together with the sputter epitaxy method effectively suppress the growth of Ge islands and result in the formation of flat Ge layers.

  20. Super-dense array of Ge quantum dots grown on Si(100) by low-temperature molecular beam epitaxy

    SciTech Connect (OSTI)

    Talochkin, A. B., E-mail: tal@isp.nsc.ru; Shklyaev, A. A. [A.V. Rzhanov Institute of Semiconductor Physics, Lavrentyev Avenue 13, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Mashanov, V. I. [A.V. Rzhanov Institute of Semiconductor Physics, Lavrentyev Avenue 13, Novosibirsk 630090 (Russian Federation)

    2014-04-14T23:59:59.000Z

    Ge layer grown on Si(100) at the low temperature of ?100?°C by molecular beam epitaxy is studied using scanning tunneling microscopy and Raman spectroscopy. It is found that crystalline and pseudomorphic to the Si substrate Ge islands are formed at the initial growth stage. The islands acquire the base size of 1.2–2.6?nm and they form arrays with the super-high density of (5–8)?×?10{sup 12}?cm{sup ?2} at 1–2?nm Ge coverages. Such a density is at least 10 times higher than that of Ge “hut” clusters grown via the Stranski-Krastanov growth mode. It is shown that areas between the crystalline Ge islands are filled with amorphous Ge, which is suggested to create potential barrier for holes localized within the islands. As a result, crystalline Ge quantum dots appear being isolated from each other.