National Library of Energy BETA

Sample records for mobile facility gan

  1. Mobile Facility

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

    govSitesMobile Facility AMF Information Science Architecture Baseline Instruments AMF1 AMF2 AMF3 MAOS AMF Fact Sheet Images Contacts AMF Deployments McMurdo Station, Antarctica, 2015-2016 Pearl Harbor, Hawaii, to San Francisco, California, 2015 Hyytiälä, Finland, 2014 Manacapuru, Brazil, 2014 Oliktok Point, Alaska, 2013 Los Angeles, California, to Honolulu, Hawaii, 2012 Cape Cod, Massachusetts, 2012 Gan Island, Maldives, 2011 Ganges Valley, India, 2011 Steamboat Springs, Colorado, 2010

  2. ARM Mobile Facilities

    SciTech Connect (OSTI)

    Orr, Brad; Coulter, Rich

    2010-12-13

    This video provides an overview of the ARM Mobile Facilities, two portable climate laboratories that can deploy anywhere in the world for campaigns of at least six months.

  3. ARM Mobile Facilities

    ScienceCinema (OSTI)

    Orr, Brad; Coulter, Rich

    2014-09-15

    This video provides an overview of the ARM Mobile Facilities, two portable climate laboratories that can deploy anywhere in the world for campaigns of at least six months.

  4. ARM - Facility News Article

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

    5, 2011 [Facility News] Team Continues Campaign Planning on Gan Island Bookmark and Share Mike Ritsche, technical operations manager for the AMF2, discusses instrumentation specifics with Gan airport and MMS officials. Mike Ritsche, technical operations manager for the AMF2, discusses instrumentation specifics with Gan airport and MMS officials. For its first international field campaign, the second ARM Mobile Facility (AMF2) is scheduled to operate on Gan Island in the Indian Ocean for the ARM

  5. ARM - ARM Mobile Facility 1 Article

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

    CenterARM Mobile Facility 1ARM Mobile Facility 1 Article Media Contact Hanna Goss hanna-dot-goss-at-pnnl-dot-gov @armnewsteam Field Notes Blog Topics Field Notes117 AGU 3 AMIE 10 ARM Aerial Facility 2 ARM Mobile Facility 1 7 ARM Mobile Facility 2 47 ARM Mobile Facility 3 1 BAECC 1 BBOP 4 CARES 1 Data Quality Office 2 ENA 2 GOAMAZON 7 HI-SCALE 4 LASIC 3 MAGIC 15 MC3E 17 PECAN 3 SGP 8 STORMVEX 29 TCAP 3 Search News Search Blog News Center All Categories What's this? Social Media Guidance News

  6. ARM Operations and Engineering Procedure Mobile Facility Site...

    Office of Scientific and Technical Information (OSTI)

    ARM Operations and Engineering Procedure Mobile Facility Site Startup Citation Details In-Document Search Title: ARM Operations and Engineering Procedure Mobile Facility Site Startup ...

  7. Deployment of ARM Aerial Facility (AAF) Scanning Mobility Particle...

    Office of Scientific and Technical Information (OSTI)

    Mobility Particle Sizer Field Campaign Report Citation Details In-Document Search Title: Deployment of ARM Aerial Facility (AAF) Scanning Mobility Particle Sizer Field ...

  8. Carbon doped GaN buffer layer using propane for high electron mobility transistor applications: Growth and device results

    SciTech Connect (OSTI)

    Li, X.; Nilsson, D.; Danielsson, Ö.; Pedersen, H.; Janzén, E.; Forsberg, U.; Bergsten, J.; Rorsman, N.

    2015-12-28

    The creation of a semi insulating (SI) buffer layer in AlGaN/GaN High Electron Mobility Transistor (HEMT) devices is crucial for preventing a current path beneath the two-dimensional electron gas (2DEG). In this investigation, we evaluate the use of a gaseous carbon gas precursor, propane, for creating a SI GaN buffer layer in a HEMT structure. The carbon doped profile, using propane gas, is a two stepped profile with a high carbon doping (1.5 × 10{sup 18 }cm{sup −3}) epitaxial layer closest to the substrate and a lower doped layer (3 × 10{sup 16 }cm{sup −3}) closest to the 2DEG channel. Secondary Ion Mass Spectrometry measurement shows a uniform incorporation versus depth, and no memory effect from carbon doping can be seen. The high carbon doping (1.5 × 10{sup 18 }cm{sup −3}) does not influence the surface morphology, and a roughness root-mean-square value of 0.43 nm is obtained from Atomic Force Microscopy. High resolution X-ray diffraction measurements show very sharp peaks and no structural degradation can be seen related to the heavy carbon doped layer. HEMTs are fabricated and show an extremely low drain induced barrier lowering value of 0.1 mV/V, demonstrating an excellent buffer isolation. The carbon doped GaN buffer layer using propane gas is compared to samples using carbon from the trimethylgallium molecule, showing equally low leakage currents, demonstrating the capability of growing highly resistive buffer layers using a gaseous carbon source.

  9. ARM Mobile Facility - Design and Schedule for Integration

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

    Mobile Facility - Design and Schedule for Integration K. B. Widener Pacific Northwest ... The design phase for developing the AMF has begun. A design review was held for the AMF in ...

  10. ARM - Field Campaign - Application of the ARM Mobile Facility...

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

    the ARM Mobile Facility (AMF) to Study the Aerosol Indirect Effects in China Campaign Links China Website ARM Data Discovery Browse Data Comments? We would love to hear from you ...

  11. Study of the effects of GaN buffer layer quality on the dc characteristics of AlGaN/GaN high electron mobility transistors

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

    Ahn, Shihyun; Zhu, Weidi; Dong, Chen; Le, Lingcong; Hwang, Ya-Hsi; Kim, Byung-Jae; Ren, Fan; Pearton, Stephen J.; Lind, Aaron G.; Jones, Kevin S.; et al

    2015-04-21

    Here we studied the effect of buffer layer quality on dc characteristics of AlGaN/GaN high electron mobility (HEMTs). AlGaN/GaN HEMT structures with 2 and 5 μm GaN buffer layers on sapphire substrates from two different vendors with the same Al concentration of AlGaN were used. The defect densities of HEMT structures with 2 and 5 μm GaN buffer layer were 7 × 109 and 5 × 108 cm₋2, respectively, as measured by transmission electron microscopy. There was little difference in drain saturation current or in transfer characteristics in HEMTs on these two types of buffer. However, there was no dispersionmore » observed on the nonpassivated HEMTs with 5 μm GaN buffer layer for gate-lag pulsed measurement at 100 kHz, which was in sharp contrast to the 71% drain current reduction for the HEMT with 2 μm GaN buffer layer.« less

  12. Mobile Climate Monitoring Facility to Sample Skies in Africa | Department

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

    of Energy Mobile Climate Monitoring Facility to Sample Skies in Africa Mobile Climate Monitoring Facility to Sample Skies in Africa January 18, 2006 - 10:47am Addthis WASHINGTON, D.C. -- The U.S. Department of Energy's Atmospheric Radiation Measurement (ARM) Program is placing a new, portable atmospheric laboratory with sophisticated instruments and data systems in Niger, Africa, to gain a better understanding of the potential impacts of Saharan dust on global climate. Dust from Africa's

  13. ARM Operations and Engineering Procedure Mobile Facility Site Startup

    SciTech Connect (OSTI)

    Voyles, Jimmy W

    2015-05-01

    This procedure exists to define the key milestones, necessary steps, and process rules required to commission and operate an Atmospheric Radiation Measurement (ARM) Mobile Facility (AMF), with a specific focus toward on-time product delivery to the ARM Data Archive. The overall objective is to have the physical infrastructure, networking and communications, and instrument calibration, grooming, and alignment (CG&A) completed with data products available from the ARM Data Archive by the Operational Start Date milestone.

  14. ARM Mobile Facility Surface Meteorology Handbook - October 2008

    SciTech Connect (OSTI)

    MT Ritsche

    2008-10-30

    The ARM Mobile Facility Surface Meteorology station (AMF MET) uses mainly conventional in situ sensors to obtain 1-minute statistics of surface wind speed, wind direction, air temperature, relative humidity, barometric pressure, and rain-rate. Additional sensors may be added to or removed from the base set of sensors depending upon the deployment location, climate regime or programmatic needs. Additionally, sensor types may change depending upon the climate regime of the deployment. These changes/additions are noted in the Deployment Locations and History section.

  15. ARM MJO Investigation Experiment on Gan Island (AMIE-Gan) Science Plan

    SciTech Connect (OSTI)

    Long, CL; Del Genio, A; Deng, M; Fu, X; Gustafson, W; Houze, R; Jakob, C; Jensen, M; Johnson, R; Liu, X; Luke, E; May, P; McFarlane, S; Minnis, P; Schumacher, C; Vogelmann, A; Wang, Y; Webster, P; Xie, S; Zhang, C

    2011-04-11

    The overarching campaign, which includes the ARM Mobile Facility 2 (AMF2) deployment in conjunction with the Dynamics of the Madden-Julian Oscillation (DYNAMO) and the Cooperative Indian Ocean experiment on intraseasonal variability in the Year 2011 (CINDY2011) campaigns, is designed to test several current hypotheses regarding the mechanisms responsible for Madden-Julian Oscillation (MJO) initiation and propagation in the Indian Ocean area. The synergy between the proposed AMF2 deployment with DYNAMO/CINDY2011, and the corresponding funded experiment on Manus, combine for an overarching ARM MJO Investigation Experiment (AMIE) with two components: AMF2 on Gan Island in the Indian Ocean (AMIE-Gan), where the MJO initiates and starts its eastward propagation; and the ARM Manus site (AMIE-Manus), which is in the general area where the MJO usually starts to weaken in climate models. AMIE-Gan will provide measurements of particular interest to Atmospheric System Research (ASR) researchers relevant to improving the representation of MJO initiation in climate models. The framework of DYNAMO/CINDY2011 includes two proposed island-based sites and two ship-based locations forming a square pattern with sonde profiles and scanning precipitation and cloud radars at both island and ship sites. These data will be used to produce a Variational Analysis data set coinciding with the one produced for AMIE-Manus. The synergy between AMIE-Manus and AMIE-Gan will allow studies of the initiation, propagation, and evolution of the convective cloud population within the framework of the MJO. As with AMIE-Manus, AMIE-Gan/DYNAMO also includes a significant modeling component geared toward improving the representation of MJO initiation and propagation in climate and forecast models. This campaign involves the deployment of the second, marine-capable, AMF; all of the included measurement systems; and especially the scanning and vertically pointing radars. The campaign will include sonde

  16. Use of ARM Mobile Facility (AMF) Data to Study Aerosol Indirect Effects in China

    SciTech Connect (OSTI)

    Li, Zhanqing

    2012-12-19

    General goals: 1) Facilitating the deployment of the ARM Mobile Facility (AMF) and Ancillary Facility (AAF) in China in 2008, 2) Processing, retrieving, improving and analyzing observation data from ground-based, air-borne and space-borne instruments; 3) Conducting a series of studies to gain insights into the direct and indirect effects of these aerosols on radiation, clouds, and precipitation using both

  17. Mobile Pit verification system design based on passive special nuclear material verification in weapons storage facilities

    SciTech Connect (OSTI)

    Paul, J. N.; Chin, M. R.; Sjoden, G. E.

    2013-07-01

    A mobile 'drive by' passive radiation detection system to be applied in special nuclear materials (SNM) storage facilities for validation and compliance purposes has been designed through the use of computational modeling and new radiation detection methods. This project was the result of work over a 1 year period to create optimal design specifications to include creation of 3D models using both Monte Carlo and deterministic codes to characterize the gamma and neutron leakage out each surface of SNM-bearing canisters. Results were compared and agreement was demonstrated between both models. Container leakages were then used to determine the expected reaction rates using transport theory in the detectors when placed at varying distances from the can. A 'typical' background signature was incorporated to determine the minimum signatures versus the probability of detection to evaluate moving source protocols with collimation. This established the criteria for verification of source presence and time gating at a given vehicle speed. New methods for the passive detection of SNM were employed and shown to give reliable identification of age and material for highly enriched uranium (HEU) and weapons grade plutonium (WGPu). The finalized 'Mobile Pit Verification System' (MPVS) design demonstrated that a 'drive-by' detection system, collimated and operating at nominally 2 mph, is capable of rapidly verifying each and every weapon pit stored in regularly spaced, shelved storage containers, using completely passive gamma and neutron signatures for HEU and WGPu. This system is ready for real evaluation to demonstrate passive total material accountability in storage facilities. (authors)

  18. Reliability of AlGaN/GaN high electron mobility transistors on low dislocation density bulk GaN substrate: Implications of surface step edges

    SciTech Connect (OSTI)

    Killat, N. E-mail: Martin.Kuball@bristol.ac.uk; Montes Bajo, M.; Kuball, M. E-mail: Martin.Kuball@bristol.ac.uk; Paskova, T.; Materials Science and Engineering Department, North Carolina State University, Raleigh, North Carolina 27695 ; Evans, K. R.; Leach, J.; Electrical and Computer Engineering Department, Virginia Commonwealth University, Richmond, Virginia 23284 ; Li, X.; Özgür, Ü.; Morkoç, H.; Chabak, K. D.; Crespo, A.; Gillespie, J. K.; Fitch, R.; Kossler, M.; Walker, D. E.; Trejo, M.; Via, G. D.; Blevins, J. D.

    2013-11-04

    To enable gaining insight into degradation mechanisms of AlGaN/GaN high electron mobility transistors, devices grown on a low-dislocation-density bulk-GaN substrate were studied. Gate leakage current and electroluminescence (EL) monitoring revealed a progressive appearance of EL spots during off-state stress which signify the generation of gate current leakage paths. Atomic force microscopy evidenced the formation of semiconductor surface pits at the failure location, which corresponds to the interaction region of the gate contact edge and the edges of surface steps.

  19. Clouds, aerosol, and precipitation in the Marine Boundary Layer: An ARM mobile facility deployment

    SciTech Connect (OSTI)

    Wood, Robert; Luke, Ed; Wyant, Matthew; Bretherton, Christopher S.; Remillard, Jasmine; Kollias, Pavlos; Fletcher, Jennifer; Stemmler, Jayson; deSzoeke, S.; Yuter, Sandra; Miller, Matthew; Mechem, David; Tselioudis, George; Chiu, Christine; Mann, Julia; O Connor, Ewan; Hogan, Robin; Dong, Xiquan; Miller, Mark; Ghate, Virendra; Jefferson, Anne; Min, Qilong; Minnis, Patrick; Palinkonda, Rabindra; Albrecht, Bruce; Hannay, Cecile; Lin, Yanluan

    2014-04-27

    The Clouds, Aerosol, and Precipitation in the Marine Boundary Layer (CAP-MBL) deployment at Graciosa Island in the Azores generated a 21-month (April 2009-December 2010) comprehensive dataset documenting clouds, aerosols, and precipitation using the Atmospheric Radiation Measurement Program (ARM) Mobile Facility (AMF). The scientific aim of the deployment is to gain improved understanding of the interactions of clouds, aerosols, and precipitation in the marine boundary layer. Graciosa Island straddles the boundary between the subtropics and midlatitudes in the Northeast Atlantic Ocean and consequently experiences a great diversity of meteorological and cloudiness conditions. Low clouds are the dominant cloud type, with stratocumulus and cumulus occurring regularly. Approximately half of all clouds contained precipitation detectable as radar echoes below the cloud base. Radar and satellite observations show that clouds with tops from 1-11 km contribute more or less equally to surface-measured precipitation at Graciosa. A wide range of aerosol conditions was sampled during the deployment consistent with the diversity of sources as indicated by back-trajectory analysis. Preliminary findings suggest important two-way interactions between aerosols and clouds at Graciosa, with aerosols affecting light precipitation and cloud radiative properties while being controlled in part by precipitation scavenging.The data from Graciosa are being compared with short-range forecasts made with a variety of models. A pilot analysis with two climate and two weather forecast models shows that they reproduce the observed time-varying vertical structure of lower-tropospheric cloud fairly well but the cloud-nucleating aerosol concentrations less well. The Graciosa site has been chosen to be a permanent fixed ARM site that became operational in October 2013.

  20. Clouds, aerosol, and precipitation in the Marine Boundary Layer: An ARM mobile facility deployment

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

    Wood, Robert; Luke, Ed; Wyant, Matthew; Bretherton, Christopher S.; Remillard, Jasmine; Kollias, Pavlos; Fletcher, Jennifer; Stemmler, Jayson; deSzoeke, S.; Yuter, Sandra; et al

    2014-04-27

    The Clouds, Aerosol, and Precipitation in the Marine Boundary Layer (CAP-MBL) deployment at Graciosa Island in the Azores generated a 21-month (April 2009-December 2010) comprehensive dataset documenting clouds, aerosols, and precipitation using the Atmospheric Radiation Measurement Program (ARM) Mobile Facility (AMF). The scientific aim of the deployment is to gain improved understanding of the interactions of clouds, aerosols, and precipitation in the marine boundary layer. Graciosa Island straddles the boundary between the subtropics and midlatitudes in the Northeast Atlantic Ocean and consequently experiences a great diversity of meteorological and cloudiness conditions. Low clouds are the dominant cloud type, with stratocumulusmore » and cumulus occurring regularly. Approximately half of all clouds contained precipitation detectable as radar echoes below the cloud base. Radar and satellite observations show that clouds with tops from 1-11 km contribute more or less equally to surface-measured precipitation at Graciosa. A wide range of aerosol conditions was sampled during the deployment consistent with the diversity of sources as indicated by back-trajectory analysis. Preliminary findings suggest important two-way interactions between aerosols and clouds at Graciosa, with aerosols affecting light precipitation and cloud radiative properties while being controlled in part by precipitation scavenging.The data from Graciosa are being compared with short-range forecasts made with a variety of models. A pilot analysis with two climate and two weather forecast models shows that they reproduce the observed time-varying vertical structure of lower-tropospheric cloud fairly well but the cloud-nucleating aerosol concentrations less well. The Graciosa site has been chosen to be a permanent fixed ARM site that became operational in October 2013.« less

  1. Clouds, Aerosols, and Precipitation in the Marine Boundary Layer: An Arm Mobile Facility Deployment

    SciTech Connect (OSTI)

    Wood, Robert; Wyant, Matthew; Bretherton, Christopher S.; Rémillard, Jasmine; Kollias, Pavlos; Fletcher, Jennifer; Stemmler, Jayson; de Szoeke, Simone; Yuter, Sandra; Miller, Matthew; Mechem, David; Tselioudis, George; Chiu, J. Christine; Mann, Julian A. L.; O’Connor, Ewan J.; Hogan, Robin J.; Dong, Xiquan; Miller, Mark; Ghate, Virendra; Jefferson, Anne; Min, Qilong; Minnis, Patrick; Palikonda, Rabindra; Albrecht, Bruce; Luke, Ed; Hannay, Cecile; Lin, Yanluan

    2015-03-01

    The Clouds, Aerosol, and Precipitation in the Marine Boundary Layer (CAP-MBL) 38 deployment at Graciosa Island in the Azores generated a 21 month (April 2009-December 2010) 39 comprehensive dataset documenting clouds, aerosols and precipitation using the Atmospheric 40 Radiation Measurement (ARM) Mobile Facility (AMF). The scientific aim of the deployment is 41 to gain improved understanding of the interactions of clouds, aerosols and precipitation in the 42 marine boundary layer. 43 Graciosa Island straddles the boundary between the subtropics and midlatitudes in the 44 Northeast Atlantic Ocean, and consequently experiences a great diversity of meteorological and 45 cloudiness conditions. Low clouds are the dominant cloud type, with stratocumulus and cumulus 46 occurring regularly. Approximately half of all clouds contained precipitation detectable as radar 47 echoes below the cloud base. Radar and satellite observations show that clouds with tops from 1-48 11 km contribute more or less equally to surface-measured precipitation at Graciosa. A wide 49 range of aerosol conditions was sampled during the deployment consistent with the diversity of 50 sources as indicated by back trajectory analysis. Preliminary findings suggest important two-way 51 interactions between aerosols and clouds at Graciosa, with aerosols affecting light precipitation 52 and cloud radiative properties while being controlled in part by precipitation scavenging. 53 The data from at Graciosa are being compared with short-range forecasts made a variety 54 of models. A pilot analysis with two climate and two weather forecast models shows that they 55 reproduce the observed time-varying vertical structure of lower-tropospheric cloud fairly well, 56 but the cloud-nucleating aerosol concentrations less well. The Graciosa site has been chosen to 57 be a long-term ARM site that became operational in October 2013.

  2. ARM - Facility News Article

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

    Interferometers Compared for ARM Mobile Facility Deployment in China Bookmark and Share ... Mobile Facility in 2008 for a field campaign to study Aerosol Indirect Effects in China. ...

  3. Facilities

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

    Facilities Facilities LANL's mission is to develop and apply science and technology to ensure the safety, security, and reliability of the U.S. nuclear deterrent; reduce global threats; and solve other emerging national security and energy challenges. Contact Operator Los Alamos National Laboratory (505) 667-5061 Some LANL facilities are available to researchers at other laboratories, universities, and industry. Unique facilities foster experimental science, support the Lab's security mission

  4. Facilities

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

    Secure and Sustainable Energy Future Mission/Facilities Facilities Tara Camacho-Lopez 2016-04-06T18:06:13+00:00 National Solar Thermal Test Facility (NSTTF) facility_nsttf_slide NSTTF's primary goal is to provide experimental engineering data for the design, construction, and operation of unique components and systems in proposed solar thermal electrical plants, which have three generic system architectures: line-focus (trough and continuous linear Fresnel reflector systems), point-focus central

  5. Ab initio study on noncompensated CrO codoping of GaN for enhanced solar energy conversion

    SciTech Connect (OSTI)

    Pan, Hui; Gu, Baohua; Eres, Gyula; Zhang, Zhenyu

    2010-03-01

    We describe a novel photocatalyst obtained by codoping GaN with CrO, according to a new "noncompensated" codoping concept based on first-principles calculations. The approach enables controllable narrowing of the GaN band gap with significantly enhanced carrier mobility and photocatalytic activity in the visible light region and thus offers immense potential for application in solar energy conversion, water splitting, and a variety of solar-assisted photocatalysis. Our calculations indicate that the formation energy for the cation doping is greatly reduced by noncompensated codoping with an anion. Although Cr doping alone can split the band gap with the formation of an intermediate band, the mobility is low due to carrier trapping by the localized states. The first-principles calculations also demonstrate that CrO codoping of GaN shifts the Fermi level into the conduction band resulting in high carrier density and mobility.

  6. ARM - Facility News Article

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

    December 4, 2010 [Facility News] Request for Proposals Now Open Bookmark and Share The ARM Climate Research Facility is now accepting applications for use of the ARM mobile facilities, aerial facility, and fixed sites. Proposals are welcome from all members of the scientific community for conducting field campaigns and scientific research using the ARM Facility. Facility availability is as follows: ARM Mobile Facility 2 (AMF2) available FY2013 ARM Mobile Facility 1 (AMF1) available March 2015

  7. Facilities

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

    Facilities The the WTGa1 turbine (aka DOE/SNL #1) retuns to power as part of a final series of commissioning tests. Permalink Gallery First Power for SWiFT Turbine Achieved during Recommissioning Facilities, News, Renewable Energy, SWIFT, Wind Energy, Wind News First Power for SWiFT Turbine Achieved during Recommissioning The Department of Energy's Scaled Wind Farm Technology (SWiFT) Facility reached an exciting milestone with the return to power production of the WTGa1 turbine (aka DOE/SNL #1)

  8. ARM - Facility News Article

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

    8, 2011 [Facility News, Publications] Journal Special Issue Includes Mobile Facility Data from Germany Bookmark and Share The ARM Mobile Facility operated in Heselbach, Germany, as part of the COPS surface network. The ARM Mobile Facility operated in Heselbach, Germany, as part of the COPS surface network. In 2007, the ARM Mobile Facility participated in one of the most ambitious field studies ever conducted in Europe-the Convective and Orographically Induced Precipitation Study (COPS). Now, 21

  9. AMF ARM Mobile FAcility

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

    at http:www.arm.govacrfsubmitproposals.stm. For more information, contact: Mark Miller Mary Jane Bartholomew AMF Site Scientist Assoc. Site Scientist (631) 344-2958 (631)...

  10. ARM - Facility News Article

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

    January 11, 2007 Facility News ARM Mobile Facility Moves to China in 2008 for Study of ... China generates exceptionally high amounts of aerosol particles whose influence on the ...

  11. ARM - AMIE Gan Island - Data Plots

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

    Gan Related Links amie.png 34h AMIE Home cindy.png 50h CINDY2011 dynamo.png 34h DYNAMO ARM Data Discovery Browse Data Outreach News & Press Blog Backgrounder (PDF, 1.2MB) Education Flyer (PDF, 2.0MB) Images ARM flickr site Official AMIE Logo AMIE Gear Experiment Planning Steering Committee AMIE-MANUS Proposal Abstract AMIE-GAN Proposal Abstract Meetings Cloud Life Cycle Working Group Deployment Operations Science Plan - TWP Manus Site (PDF, 2.1 MB) Science Plan - Gan Island Site (PDF, 2.0

  12. ARM - Facility News Article

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

    Data Available from ARM Mobile Facility Deployment in China Bookmark and Share The Study of Aerosol Indirect Effects in China was anchored by the ARM Mobile Facility in Shouxian ...

  13. Tellurium n-type doping of highly mismatched amorphous GaN1-xAsx alloys in plasma-assisted molecular beam epitaxy

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

    Novikov, S. V.; Ting, M.; Yu, K. M.; Sarney, W. L.; Martin, R. W.; Svensson, S. P.; Walukiewicz, W.; Foxon, C. T.

    2014-10-01

    In this paper we report our study on n-type Te doping of amorphous GaN1-xAsx layers grown by plasma-assisted molecular beam epitaxy. We have used a low temperature PbTe source as a source of tellurium. Reproducible and uniform tellurium incorporation in amorphous GaN1-xAsx layers has been successfully achieved with a maximum Te concentration of 9×10²⁰ cm⁻³. Tellurium incorporation resulted in n-doping of GaN1-xAsx layers with Hall carrier concentrations up to 3×10¹⁹ cm⁻³ and mobilities of ~1 cm²/V s. The optimal growth temperature window for efficient Te doping of the amorphous GaN1-xAsx layers has been determined.

  14. Measurement of fenestration net energy performance: Considerations leading to development of a Mobile Window Thermal Test (MoWitt) facility

    SciTech Connect (OSTI)

    Klems, J.H.

    1988-08-01

    The authors present a detailed consideration of the energy flows entering a building space and the effect of random measurement errors on determining fenestration performance. Estimates of error magnitudes are made for a passive test cell; they show that a more accurate test facility is needed for reliable measurements on fenestration systems with thermal resistance 2-10 times that of single glazing or with shading coefficients less than 0.7. A test facility of this type, built at Lawrence Berkeley Laboratory, is described. The effect of random errors in this facility is discussed and computer calculations of its performance are presented. The discussion shows that, for any measurement facility, random errors are most serious in nighttime measurements, and systematic errors are most important in daytime measurements. It is concluded that, for this facility, errors from both sources should be small.

  15. Atmospheric Radiation Measurement Climate Research Facility Operations...

    Office of Scientific and Technical Information (OSTI)

    Title: Atmospheric Radiation Measurement Climate Research Facility Operations Quarterly ... Atmospheric Radiation Measurement (ARM) Climate Research Facility fixed and mobile sites ...

  16. Facility Floorplan

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

    facility floorplan Facility Floorplan

  17. ARM - Facility News Article

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

    January 11, 2011 [Facility News] ARM Mobile Facility Completes Extended Campaign in the Azores; Next Stop-India Bookmark and Share The ARM Mobile Facility obtained data on Graciosa Island in the Azores from May 2009 through December 2010--its longest deployment to date. The ARM Mobile Facility obtained data on Graciosa Island in the Azores from May 2009 through December 2010--its longest deployment to date. December 31, 2010, marked the last official day of data collection for the Clouds,

  18. ARM - Facility News Article

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

    , 2009 [Facility News] Mobile Facility Begins Marine Cloud Study in the Azores Bookmark and Share Located next to the airport on Graciosa Island, the ARM Mobile Facility's comprehensive and sophisticated instrument suite will obtain atmospheric measurements from the marine boundary layer. Located next to the airport on Graciosa Island, the ARM Mobile Facility's comprehensive and sophisticated instrument suite will obtain atmospheric measurements from the marine boundary layer. Extended

  19. ARM - Facility News Article

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

    March 22, 2007 [Facility News] GEWEX News Features Dust Data from ARM Mobile Facility Deployment Bookmark and Share Data from the recent deployment of the ARM Mobile Facility are featured in the February issue of GEWEX News. The February 2007 issue (Vol. 17, No. 1) of GEWEX News features early results from special observing periods of the African Monsoon Mutidisciplinary Analysis, including data obtained by the ARM Mobile Facility (AMF). The AMF was stationed in the central Sahel from January

  20. ARM - Facility News Article

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

    June 1, 2015 [Facility News] BAMS Features Results of 21-Month ARM Deployment Bookmark and Share Low clouds were observed typically at the Graciosa site during the 21-month ARM Mobile Facility deployment. Low clouds were observed typically at the Graciosa site during the 21-month ARM Mobile Facility deployment. Featured in the March 2015 Bulletin of the American Meteorological Society (BAMS), the 21-month ARM mobile facility deployment in the Azores was the longest of its type in a non-tropical

  1. ARM - Facility News Article

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

    December 21, 2010 [Education, Facility News] NSF Student Travel Fellowship for DYNAMO Field Campaign Bookmark and Share As part of the DYNAMO (Dynamics of the MJO) field campaign, which includes the AMIE-Gan campaign, several student travel fellowships funded by the National Science Foundation are available for advanced graduate students and recently graduated postdoctoral associates, especially those from under-represented groups. DYNAMO is the US contribution to the international field program

  2. ARM - News from the Gan Island Deployment

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

    News from the Gan Island Deployment Related Links amie.png 34h AMIE Home cindy.png 50h CINDY2011 dynamo.png 34h DYNAMO ARM Data Discovery Browse Data Outreach News & Press Blog Backgrounder (PDF, 1.2MB) Education Flyer (PDF, 2.0MB) Images ARM flickr site Official AMIE Logo AMIE Gear Experiment Planning Steering Committee AMIE-MANUS Proposal Abstract AMIE-GAN Proposal Abstract Meetings Cloud Life Cycle Working Group Deployment Operations Science Plan - TWP Manus Site (PDF, 2.1 MB) Science

  3. Mechanism of the GaN LED efficiency falloff with increasing current

    SciTech Connect (OSTI)

    Bochkareva, N. I.; Voronenkov, V. V.; Gorbunov, R. I.; Zubrilov, A. S.; Lelikov, Y. S.; Latyshev, F. E.; Rebane, Y. T.; Tsyuk, A. I.; Shreter, Y. G.

    2010-06-15

    The quantum efficiency of GaN LED structures has been studied at various temperatures and biases. It was found that an efficiency falloff is observed with increasing current density and, simultaneously, the tunnel component of the current through the LED grows and the quasi-Fermi levels reach the mobility edge in the InGaN active layer. It is shown that the internal quantum efficiency falloff with increasing current density is due to the carrier leakage from the quantum well as a result of tunnel transitions from its band-tail states to local defect-related energy levels within the energy gaps of the barrier layers.

  4. ARM - Field Campaign - AMIE-Gan Ancillary Disdrometer

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

    govCampaignsAMIE-Gan Ancillary Disdrometer Campaign Links Field Campaign Report ARM Data Discovery Browse Data Related Campaigns ARM MJO Investigation Experiment on Gan Island 2011.10.01, Long, AMF Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : AMIE-Gan Ancillary Disdrometer 2012.01.01 - 2012.02.10 Lead Scientist : Mariko Oue For data sets, see below. Abstract As part of the AMIE-Gan campaign, an ancillary disdrometer for comparison

  5. ARM - Facility News Article

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

    Africa Bookmark and Share ARM operations staff prepare the ARM Mobile Facility in Point Reyes, California, for delivery to Africa, upon the successful conclusion of the first field...

  6. ARM - Facility News Article

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

    of ARM Mobile Facility to Occur on California Coast Bookmark and Share Image - Point Reyes Beach Point Reyes National Seashore, on the California coast north of San Francisco,...

  7. ARM - Facility News Article

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

    Mixed-Phase Arctic Cloud Experiment, and the ARM Mobile Facility's deployments at Point Reyes National Seashore and Niamey, Niger, West Africa. ARM researchers, including ARM's...

  8. ARM - Facility News Article

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

    ARM's two mobile facilities have completed field campaigns in the United States, Africa, Germany, the Azores, India, and the Maldives. They are currently preparing for yearlong...

  9. ARM - Facility News Article

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

    Antarctica is the highest, driest, coldest, and windiest continent. It contains 90% of the ... which manages ARM mobile facilities and Eastern North Atlantic site in the Azores

  10. ARM - Facility News

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

    News Media Contact Hanna Goss hanna-dot-goss-at-pnnl-dot-gov @armnewsteam Field Notes Blog Topics Field Notes117 AGU 3 AMIE 10 ARM Aerial Facility 2 ARM Mobile Facility 1 7 ARM Mobile Facility 2 47 ARM Mobile Facility 3 1 BAECC 1 BBOP 4 CARES 1 Data Quality Office 2 ENA 2 GOAMAZON 7 HI-SCALE 4 LASIC 3 MAGIC 15 MC3E 17 PECAN 3 SGP 8 STORMVEX 29 TCAP 3 Search News Search Blog News Center All Categories What's this? Social Media Guidance News Center All Categories Features and Releases Facility

  11. ARM - Facility News Archive

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

    Archive Media Contact Hanna Goss hanna-dot-goss-at-pnnl-dot-gov @armnewsteam Field Notes Blog Topics Field Notes117 AGU 3 AMIE 10 ARM Aerial Facility 2 ARM Mobile Facility 1 7 ARM Mobile Facility 2 47 ARM Mobile Facility 3 1 BAECC 1 BBOP 4 CARES 1 Data Quality Office 2 ENA 2 GOAMAZON 7 HI-SCALE 4 LASIC 3 MAGIC 15 MC3E 17 PECAN 3 SGP 8 STORMVEX 29 TCAP 3 Search News Search Blog News Center All Categories What's this? Social Media Guidance News Center All Categories Features and Releases Facility

  12. GaN: Defect and Device Issues

    SciTech Connect (OSTI)

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

    1998-11-09

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

  13. GaN Initiative for Grid Applications (GIGA)

    SciTech Connect (OSTI)

    Turner, George

    2015-07-03

    For nearly 4 ½ years, MIT Lincoln Laboratory (MIT/LL) led a very successful, DoE-funded team effort to develop GaN-on-Si materials and devices, targeting high-voltage (>1 kV), high-power, cost-effective electronics for grid applications. This effort, called the GaN Initiative for Grid Applications (GIGA) program, was initially made up of MIT/LL, the MIT campus group of Prof. Tomas Palacios (MIT), and the industrial partner M/A Com Technology Solutions (MTS). Later in the program a 4th team member was added (IQE MA) to provide commercial-scale GaN-on-Si epitaxial materials. A basic premise of the GIGA program was that power electronics, for ubiquitous utilization -even for grid applications - should be closer in cost structure to more conventional Si-based power electronics. For a number of reasons, more established GaN-on-SiC or even SiC-based power electronics are not likely to reach theses cost structures, even in higher manufacturing volumes. An additional premise of the GIGA program was that the technical focus would be on materials and devices suitable for operating at voltages > 1 kV, even though there is also significant commercial interest in developing lower voltage (< 1 kV), cost effective GaN-on-Si devices for higher volume applications, like consumer products. Remarkable technical progress was made during the course of this program. Advances in materials included the growth of high-quality, crack-free epitaxial GaN layers on large-diameter Si substrates with thicknesses up to ~5 μm, overcoming significant challenges in lattice mismatch and thermal expansion differences between Si and GaN in the actual epitaxial growth process. Such thick epilayers are crucial for high voltage operation of lateral geometry devices such as Schottky barrier (SB) diodes and high electron mobility transistors (HEMTs). New “Normally-Off” device architectures were demonstrated – for safe operation of power electronics circuits. The trade-offs between lateral and

  14. ARM - Facility News Article

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

    January 15, 2006 [Facility News] ARM Mobile Facility Begins Year-Long Deployment in Africa Bookmark and Share Beginning on January 9, the ARM Mobile Facility began officially collecting atmospheric data from a location at the airport in Niamey, Niger, Africa. As part of the RADAGAST field campaign, the AMF will measure the effects of absorbing aerosols from desert dust in the dry season, and the effects of deep convective clouds and associated moisture loadings on the transmission of atmospheric

  15. ARM - Facility News Article

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

    20, 2010 [Facility News] ARM Mobile Facility Blogs from Steamboat Springs Bookmark and Share This month, team members for the second ARM Mobile Facility (AMF2) are in Steamboat Springs, Colorado, preparing for the Storm Peak Lab Validation Experiment, or STORMVEX. Follow their progress on the AMF2 blog, as they install instrumentation at three sites on Mount Werner. This is the first topic for the ARM News Center blog, which was developed to share a variety of ARM stories and experiences. Be

  16. ARM - Facility News Article

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

    30, 2005 [Facility News] Coastal Clouds Field Campaign Takes Off in July Bookmark and Share The 2-channel NFOV gets careful attention as it joins the suite of instruments collecting data for the ARM Mobile Facility field campaign at Point Reyes National Seashore. Since March 2005, the ARM Mobile Facility (AMF) has been at Point Reyes National Seashore in northern California for the Marine Stratus Radiation, Aerosol, and Drizzle Intensive Operational Period. The goals of this 6-month field

  17. ARM - Facility News Article

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

    Mobile Facility Beta Testing Complete; System Headed to California Seashore Bookmark and Share A key addition to the ARM Climate Research Facility scientific infrastructure is ready to roll...literally. In February, the ARM Mobile Facility (AMF) is being packed up and shipped from Richland, Washington, to the Point Reyes National Seashore north of San Francisco, California. There, it will be reassembled in preparation for its first deployment as part of a 6-month experiment to study the

  18. ARM - Facility News Article

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

    1, 2011 [Facility News] Data from Field Campaign in Black Forest, Germany, are Red Hot Bookmark and Share During COPS, the ARM Mobile Facility operated in Heselbach, Germany, obtaining measurements encompassing the entire life cycle of precipitation. The AMF site also hosted a number of guest instruments for supplemental field campaigns throughout the deployment. During COPS, the ARM Mobile Facility operated in Heselbach, Germany, obtaining measurements encompassing the entire life cycle of

  19. ARM - Facility News Article

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

    8, 2012 [Data Announcements, Facility News] New Data from Greenland for Arctic Climate Research Bookmark and Share Instruments for ICECAPS operate on top and inside of the Mobile Science Facility at Summit Station in Greenland. Instruments for ICECAPS operate on top and inside of the Mobile Science Facility at Summit Station in Greenland. In 2010, researchers installed a powerful suite of climate and weather instruments at Greenland's frozen research outpost, Summit Station, for a long-term

  20. ARM - Facility News Article

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

    January 15, 2008 [Facility News] ARM Mobile Facility Completes Field Campaign in Germany Bookmark and Share Researchers will study severe precipitation events that occurred in August and October 2007, stalling Rhine River traffic and causing flooding in portions of Germany. (Image source: DW-WORLD.DE) Operations at the ARM Mobile Facility (AMF) site in Heselbach, Germany, officially came to a close on January 1, 2008. As one of several measurement "supersites" situated throughout the

  1. ARM - Facility News Article

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

    22, 2011 [Facility News] Request for Proposals Now Open Bookmark and Share The ARM Climate Research Facility is now accepting applications for use of an ARM mobile facility (AMF), the ARM aerial facility (AAF), and fixed sites. Proposals are welcome from all members of the scientific community for conducting field campaigns and scientific research using the ARM Facility, with availability as follows: AMF2 available December 2013 AMF1 available March 2015 AAF available between June and October

  2. Integrating AlGaN/GaN high electron mobility transistor with Si: A comparative study of integration schemes

    SciTech Connect (OSTI)

    Mohan, Nagaboopathy; Raghavan, Srinivasan; Manikant,; Soman, Rohith

    2015-10-07

    AlGaN/GaN high electron mobility transistor stacks deposited on a single growth platform are used to compare the most common transition, AlN to GaN, schemes used for integrating GaN with Si. The efficiency of these transitions based on linearly graded, step graded, interlayer, and superlattice schemes on dislocation density reduction, stress management, surface roughness, and eventually mobility of the 2D-gas are evaluated. In a 500 nm GaN probe layer deposited, all of these transitions result in total transmission electron microscopy measured dislocations densities of 1 to 3 × 10{sup 9}/cm{sup 2} and <1 nm surface roughness. The 2-D electron gas channels formed at an AlGaN-1 nm AlN/GaN interface deposited on this GaN probe layer all have mobilities of 1600–1900 cm{sup 2}/V s at a carrier concentration of 0.7–0.9 × 10{sup 13}/cm{sup 2}. Compressive stress and changes in composition in GaN rich regions of the AlN-GaN transition are the most effective at reducing dislocation density. Amongst all the transitions studied the step graded transition is the one that helps to implement this feature of GaN integration in the simplest and most consistent manner.

  3. Windows and Building Envelope Facilities

    Broader source: Energy.gov [DOE]

    LBNL’s has three facilities specifically dedicated to windows: the Optical Properties Laboratory, the Infrared Thermography Laboratory, and the Mobile Window Thermal Test Facility (MoWiTT). These...

  4. Ge doped GaN with controllable high carrier concentration for...

    Office of Scientific and Technical Information (OSTI)

    Ge doped GaN with controllable high carrier concentration for plasmonic applications Citation Details In-Document Search Title: Ge doped GaN with controllable high carrier...

  5. ARM - Facility News Article

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

    Science Board Established for ARM Climate Research Facility Bookmark and Share The scientific infrastructure established by the ARM Program - heavily instrumented research sites, the ARM Data Archive, and the ARM Mobile Facility under development - is now available for use by scientists worldwide through the ARM Climate Research Facility. As a national user facility, this unique asset provides the opportunity for a broader national and international research community to study global change. The

  6. ARM - Facility News Article

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

    July 18, 2016 [Facility News] Next Round of Deadlines for Small Campaigns Coming Up Bookmark and Share The next deadline to propose for smaller field campaigns will be August 22. Small campaigns do not require a full deployment of ARM Facility equipment, like an ARM mobile or aerial facility. They require just an instrument or two, or are in conjunction with a larger facility operation. Costing less than $25,000, these campaigns give researchers access to ARM's equipment to perform focused,

  7. ARM - Facility News Article

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

    Preparations Underway for 2007 ARM Mobile Facility Deployment in Germany Bookmark and Share In the Black Forest region of Germany, the COPS field campaign will cover an area of ...

  8. ARM - Facility News Article

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

    the ARM Mobile Facility. ARM participated in the Student Exploration of Research in the Earth and Space Sciences (EXPRESS) program held on the last day of the 2005 AGU Fall...

  9. ARM - Facility News Article

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

    Mobile Facility Anchors Multi-site Aerosol Study in China Bookmark and Share The AMF ... data collection at four different sites for the Aerosol Indirect Effects Study in China. ...

  10. ARM - Facility News Article

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

    test period, plans are to deploy the new technology to both ARM Mobile Facilities and the Tropical Western Pacific sites in Darwin, Australia, and Manus Island, Papua New Guinea. ...

  11. ARM - Facility News Article

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

    ARM's New Radar Operating Paradigm Aims to Maximize Performance Bookmark and Share Maintaining the pulse of the radar network is vital to research A Scanning ARM Cloud Radar is deployed with the ARM Mobile Facility on Antarctica for the ARM West Antarctic Radiation Experiment campaign. A Scanning ARM Cloud Radar is deployed with the ARM Mobile Facility on Antarctica for the ARM West Antarctic Radiation Experiment campaign. Radars have been getting a lot of attention at ARM in the last few

  12. ARM - Facility News Article

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

    Guest Instruments to Collect Aerosol Data During Coastal Field Campaign Bookmark and Share The counter-flow virtual impactor (inset), which can characterize aerosol particles in cloud droplets, joins a number of other guest instruments at the ARM Mobile Facility deployment site at Point Reyes National Seashore in California. The ARM Mobile Facility's (AMF's) inaugural field campaign, the Marine Stratus Radiation Aerosol and Drizzle (MASRAD) Intensive Operational Period, is well underway at Point

  13. ARM - Facility News Article

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

    4, 2012 [Facility News] New Organization to Optimize ARM Radar Data Bookmark and Share Every ARM fixed and mobile site now includes both scanning (left) and zenith-pointing (right) cloud radars. The fixed sites also include scanning precipitation radars. Every ARM fixed and mobile site now includes both scanning (left) and zenith-pointing (right) cloud radars. The fixed sites also include scanning precipitation radars. In the past few years, the ARM Facility added 19 new scanning cloud and

  14. High Voltage GaN Schottky Rectifiers

    SciTech Connect (OSTI)

    CAO,X.A.; CHO,H.; CHU,S.N.G.; CHUO,C.-C.; CHYI,J.-I.; DANG,G.T.; HAN,JUNG; LEE,C.-M.; PEARTON,S.J.; REN,F.; WILSON,R.G.; ZHANG,A.P.

    1999-10-25

    Mesa and planar GaN Schottky diode rectifiers with reverse breakdown voltages (V{sub RB}) up to 550V and >2000V, respectively, have been fabricated. The on-state resistance, R{sub ON}, was 6m{Omega}{center_dot} cm{sup 2} and 0.8{Omega}cm{sup 2}, respectively, producing figure-of-merit values for (V{sub RB}){sup 2}/R{sub ON} in the range 5-48 MW{center_dot}cm{sup -2}. At low biases the reverse leakage current was proportional to the size of the rectifying contact perimeter, while at high biases the current was proportional to the area of this contact. These results suggest that at low reverse biases, the leakage is dominated by the surface component, while at higher biases the bulk component dominates. On-state voltages were 3.5V for the 550V diodes and {ge}15 for the 2kV diodes. Reverse recovery times were <0.2{micro}sec for devices switched from a forward current density of {approx}500A{center_dot}cm{sup -2} to a reverse bias of 100V.

  15. Conductivity based on selective etch for GaN devices and applications thereof

    DOE Patents [OSTI]

    Zhang, Yu; Sun, Qian; Han, Jung

    2015-12-08

    This invention relates to methods of generating NP gallium nitride (GaN) across large areas (>1 cm.sup.2) with controlled pore diameters, pore density, and porosity. Also disclosed are methods of generating novel optoelectronic devices based on porous GaN. Additionally a layer transfer scheme to separate and create free-standing crystalline GaN thin layers is disclosed that enables a new device manufacturing paradigm involving substrate recycling. Other disclosed embodiments of this invention relate to fabrication of GaN based nanocrystals and the use of NP GaN electrodes for electrolysis, water splitting, or photosynthetic process applications.

  16. Highly transparent ammonothermal bulk GaN substrates

    SciTech Connect (OSTI)

    Jiang, WK; Ehrentraut, D; Downey, BC; Kamber, DS; Pakalapati, RT; Do Yoo, H; D'Evelyn, MP

    2014-10-01

    A novel apparatus has been employed to grow ammonothermal (0001) gallium nitride (GaN) with diameters up to 2 in The crystals have been characterized by x-ray diffraction rocking-curve (XRC) analysis, optical and scanning electron microscopy (SEM), cathodoluminescence (CL), and optical spectroscopy. High crystallinity GaN with FWHM values about 20-50 arcsec and dislocation densities below 1 x 10(5) cm(-2) have been obtained. High optical transmission was achieved with an optical absorption coefficient below 1 cm(-1) at a wavelength of 450 nm. (C) 2014 Elsevier B.V. All rights reserved.

  17. Ferromagnetism in undoped One-dimensional GaN Nanowires

    SciTech Connect (OSTI)

    Jeganathan, K. E-mail: jagan@physics.bdu.ac.in; Purushothaman, V.; Debnath, R.; Arumugam, S.

    2014-05-15

    We report an intrinsic ferromagnetism in vertical aligned GaN nanowires (NW) fabricated by molecular beam epitaxy without any external catalyst. The magnetization saturates at ?0.75 emu/gm with the applied field of 3000 Oe for the NWs grown under the low-Gallium flux of 2.4 10{sup ?8} mbar. Despite a drop in saturation magnetization, narrow hysteresis loop remains intact regardless of Gallium flux. Magnetization in vertical standing GaN NWs is consistent with the spectral analysis of low-temperature photoluminescence pertaining to Ga-vacancies associated structural defects at the nanoscale.

  18. Testing the effectiveness of mobile home weatherization measures in a controlled environment: The SERI CMFERT (Collaborative Manufactured Buildings Facility for Energy Research and Training) Project

    SciTech Connect (OSTI)

    Judkoff, R.D.; Hancock, C.E.; Franconi, E.

    1990-03-01

    For several years the Solar Energy Research Institute has been testing the effectiveness of mobile home weatherization measures, with the support of the US DOE Office of State and Local Assistance Programs Weatherization Assistance Program, the DOE Office of Buildings and Community Systems, the seven states within the federal Weatherization Region 7, the Colorado Division of Housing, and the DOE Denver Support Office. During the winter of 1988--89, several weatherization measures were thermally tested on three mobile homes under controlled conditions inside a large environmental enclosure. The effects of each weatherization measure on conduction losses, infiltration losses, and combined furnace and duct-delivered heat efficiency were monitored. The retrofit options included air sealing, duct repair, furnace tune-up, interior storm panels, floor insulation, and roof insulation. The study demonstrated that cost-effective heating energy savings of about 20% to 50% are possible if weatherization techniques adapted to the special construction details in mobile homes are applied. 24 refs., 18 figs., 9 tabs.

  19. ARM - Facility News Article

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

    12, 2015 [Facility News] Seeing the Silver Lining: Challenges and Champions of Arctic Cloud Studies on Alaska's North Slope Bookmark and Share Unmanned Aircraft at Oliktok Point The AMF3 is the newest of the ARM mobile facilities and will be stationed on the North Slope for an extended period. The AMF3 is the newest of the ARM mobile facilities and will be stationed on the North Slope for an extended period. Welcome to the North Slope of Alaska, home to polar bears, caribou, arctic foxes,

  20. Properties of H, O and C in GaN

    SciTech Connect (OSTI)

    Pearton, S.J.; Abernathy, C.R.; Lee, J.W.

    1996-04-01

    The electrical properties of the light ion impurities H, O and C in GaN have been examined in both as-grown and implanted material. H is found to efficiently passivate acceptors such as Mg, Ca and C. Reactivation occurs at {ge} 450 C and is enhanced by minority carrier injection. The hydrogen does not leave the GaN crystal until > 800 C, and its diffusivity is relatively high ({approximately} 10{sup {minus}11} cm{sup 2}/s) even at low temperatures (< 200 C) during injection by wet etching, boiling in water or plasma exposure. Oxygen shows a low donor activation efficiency when implanted into GaN, with an ionization level of 30--40 meV. It is essentially immobile up to 1,100 C. Carbon can produce low p-type levels (3 {times} 10{sup 17} cm{sup {minus}3}) in GaN during MOMBE, although there is some evidence it may also create n-type conduction in other nitrides.

  1. Refractive index of erbium doped GaN thin films

    SciTech Connect (OSTI)

    Alajlouni, S.; Sun, Z. Y.; Li, J.; Lin, J. Y.; Jiang, H. X.; Zavada, J. M.

    2014-08-25

    GaN is an excellent host for erbium (Er) to provide optical emission in the technologically important as well as eye-safe 1540 nm wavelength window. Er doped GaN (GaN:Er) epilayers were synthesized on c-plane sapphire substrates using metal organic chemical vapor deposition. By employing a pulsed growth scheme, the crystalline quality of GaN:Er epilayers was significantly improved over those obtained by conventional growth method of continuous flow of reaction precursors. X-ray diffraction rocking curve linewidths of less than 300 arc sec were achieved for the GaN (0002) diffraction peak, which is comparable to the typical results of undoped high quality GaN epilayers and represents a major improvement over previously reported results for GaN:Er. Spectroscopic ellipsometry was used to determine the refractive index of the GaN:Er epilayers in the 1540 nm wavelength window and a linear dependence on Er concentration was found. The observed refractive index increase with Er incorporation and the improved crystalline quality of the GaN:Er epilayers indicate that low loss GaN:Er optical waveguiding structures are feasible.

  2. AMIE Gan Island Ancillary Disdrometer Field Campaign...

    Office of Scientific and Technical Information (OSTI)

    Ancillary Disdrometer Field Campaign Report M Oue April 2016 CLIMATE RESEARCH FACILITY DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. ...

  3. Atmospheric Radiation Measurement Climate Research Facility ...

    Office of Scientific and Technical Information (OSTI)

    ARM Aerial Vehicles Program. * Successful deployment of the ARM Mobile Facility in Germany, including hosting nearly a dozen guest instruments and drawing almost 5000 visitors ...

  4. Structural defects in GaN revealed by Transmission Electron Microscopy

    SciTech Connect (OSTI)

    Liliental-Weber, Zuzanna

    2014-04-18

    This paper reviews the various types of structural defects observed by Transmission Electron Microscopy in GaN heteroepitaxial layers grown on foreign substrates and homoepitaxial layers grown on bulk GaN substrates. The structural perfection of these layers is compared to the platelet self-standing crystals grown by High Nitrogen Pressure Solution. Defects in undoped and Mg doped GaN are discussed. Some models explaining the formation of inversion domains in heavily Mg doped layers that are possible defects responsible for the difficulties of p-doping in GaN are also reviewed.

  5. Structural defects in GaN revealed by Transmission Electron Microscopy

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

    Liliental-Weber, Zuzanna

    2014-09-08

    This paper reviews the various types of structural defects observed by Transmission Electron Microscopy in GaN heteroepitaxial layers grown on foreign substrates and homoepitaxial layers grown on bulk GaN substrates. The structural perfection of these layers is compared to the platelet self-standing crystals grown by High Nitrogen Pressure Solution. Defects in undoped and Mg doped GaN are discussed. Lastly, some models explaining the formation of inversion domains in heavily Mg doped layers that are possible defects responsible for the difficulties of p-doping in GaN are also reviewed.

  6. ARM - Facility News Article

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

    4, 2013 [Facility News] Work Cut Out for ARM Science Board Bookmark and Share With a new fixed site on the horizon in the Azores, a third ARM Mobile Facility gearing up for action in the Arctic, and more aircraft probes and sensors than scientists can shake a stick at, the ARM Facility continues to expand its considerable suite of assets for conducting climate research. Along with this impressive inventory comes the responsibility to ensure the Facility is supporting the highest-value science

  7. ARM - Facility News Article

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

    Enchanted Isle Selected as Site for 2009 ARM Mobile Facility Deployment Bookmark and Share Graciosa Island, also known as White Island, covers an area of about 62 km². Meaning "enchanting," Graciosa is the beneficiary of a mild tropical climate throughout most of the year. In 2009, the ARM Mobile Facility will be deployed in the Azores to support the Clouds, Aerosol, and Precipitation in the Marine Boundary Layer (CAP-MBL) field campaign. From April through December, the AMF will be

  8. ARM - Facility News Article

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

    Mapping It Up With Google Bookmark and Share "Thumbtacks" help ARM website users identify where the ARM sites are, including the ARM Mobile Facility deployments. The online ARM sites map was recently integrated with Google(tm) Maps API technology to enhance ARM website user's experience. Web visitors and ARM Data Archive subscribers can now not only see where ARM facilities are located around the world and link to associated web pages, but use Google mapping technology to zoom

  9. ARM - Facility News Article

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

    31, 2005 [Facility News] Ancillary Site to Provide Key Data from Africa Bookmark and Share In January 2006, the ARM Mobile Facility (AMF) begins a year-long field campaign in Africa as part of a multi-year international experiment called the African Monsoon Multidisciplinary Analysis (AMMA). The AMF will be placed at the airport in Niamey, Niger, well within view of the Global Earth Radiation Budget (GERB) geostationary satellite. Cloud and radiative property measurements collected by the AMF

  10. ARM - Facility News Article

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

    April 30, 2008 [Facility News] ARM Outreach Materials Chosen for Earth Day Display in Washington DC Bookmark and Share Posters for the ARM Mobile Facility and ARM Education and Outreach were selected for the 2008 Earth Day display at DOE Headquarters. Earth Day is officially honored each year on April 22, however, many groups sponsor activities throughout the entire month of April. At DOE Headquarters in Washington DC, two ARM posters were selected to join a poster display representing programs

  11. ARM - Facility News Article

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

    15, 2007 [Facility News] Microwave Radiometers Put to the Test in Germany Bookmark and Share A 2-channel microwave radiometer (left) and a 12-channel microwave radiometer profiler (right) are part of a larger collection of instruments deployed at the ARM Mobile Facility site in Heselbach, Germany, in 2007. Microwave radiometers (MWRs) are instruments used to measure emissions of water vapor and liquid water molecules in the atmosphere at specific microwave frequencies. Different MWRs are used to

  12. ARM - Facility News Article

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

    June 30, 2007 [Facility News] New Radar Wind Profiler Joins AMF Instrument Suite in Germany Bookmark and Share The 1290 MHz wind profiler (foreground) joins the eddy correlation system (background) for the 9-month deployment in Germany. A new 1290 MHz radar wind profiler has joined the ARM Mobile Facility instrument suite for the Convective and Orographic Precipitation Study (COPS) in Germany. This system operates similarly to a Doppler radar and provides measurements of backscattered

  13. Intelligent mobile security systems

    SciTech Connect (OSTI)

    Allen, M.S. )

    1991-01-01

    This paper reports that mobile security systems are becoming increasingly important to military (Army, Air Force) and non-military (Drug Enforcement Agency, Border Patrol) organizations as the level and sophistication of terrorist activity increases. Frequently, organizations are required to deploy at remote sites on little notice. To ensure protection of life and equipment, security systems are sometimes required. Often, the personnel deployed on these missions are not adequately trained in the selection, installation, and operation of today's complex security equipment. The Intelligent Mobile Security System (IMSS) concept, as being developed by Sandia National Laboratories (SNL), allows untrained, non-technical personnel to configure, deploy, operate, and troubleshoot temporary/mobile physical security system. The IMSS may be used at nuclear facilities.

  14. Nuclear Facilities Production Facilities

    National Nuclear Security Administration (NNSA)

    Facilities Production Facilities Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. Sand 2011-4582P. ENERGY U.S. DEPARTMENT OF Gamma Irradiation Facility (GIF) The GIF provides test cells for the irradiation of experiments with high-intensity gamma ray sources. The main features

  15. Sandia Energy - Patent Awarded for the Fuel Cell Mobile Light

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

    Patent Awarded for the Fuel Cell Mobile Light Home Energy CRF Facilities Partnership News Energy Efficiency News & Events Systems Engineering Center for Infrastructure Research and...

  16. Data Management Facility Operations Plan

    SciTech Connect (OSTI)

    Keck, Nicole N

    2014-06-30

    The Data Management Facility (DMF) is the data center that houses several critical Atmospheric Radiation Measurement (ARM) Climate Research Facility services, including first-level data processing for the ARM Mobile Facilities (AMFs), Eastern North Atlantic (ENA), North Slope of Alaska (NSA), Southern Great Plains (SGP), and Tropical Western Pacific (TWP) sites, as well as Value-Added Product (VAP) processing, development systems, and other network services.

  17. ARM - SGP Extended Facility

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

    Extended Facility SGP Related Links Virtual Tour Facilities and Instruments Central Facility Boundary Facility Extended Facility Intermediate Facility Radiometric Calibration...

  18. ARM - SGP Intermediate Facility

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

    Intermediate Facility SGP Related Links Virtual Tour Facilities and Instruments Central Facility Boundary Facility Extended Facility Intermediate Facility Radiometric Calibration...

  19. ARM - SGP Central Facility

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

    Central Facility SGP Related Links Virtual Tour Facilities and Instruments Central Facility Boundary Facility Extended Facility Intermediate Facility Radiometric Calibration...

  20. This invention relates to methods of generating NP gallium nitride (GaN) across large areas (>1 cm.sup.2) with controlled pore diameters, pore density, and porosity. Also disclosed are methods of generating novel optoelectronic devices based on porous GaN. Additionally a layer transfer scheme to separate and create free-standing crystalline GaN thin layers is disclosed that enables a new device manufacturing paradigm involving substrate recycling. Other disclosed embodiments of this invention relate to fabrication of GaN based nanocrystals and the use of NP GaN electrodes for electrolysis, water splitting, or photosynthetic process applications.

    DOE Patents [OSTI]

    Zhang, Yu; Sun, Qian; Han, Jung

    2015-12-08

    This invention relates to methods of generating NP gallium nitride (GaN) across large areas (>1 cm.sup.2) with controlled pore diameters, pore density, and porosity. Also disclosed are methods of generating novel optoelectronic devices based on porous GaN. Additionally a layer transfer scheme to separate and create free-standing crystalline GaN thin layers is disclosed that enables a new device manufacturing paradigm involving substrate recycling. Other disclosed embodiments of this invention relate to fabrication of GaN based nanocrystals and the use of NP GaN electrodes for electrolysis, water splitting, or photosynthetic process applications.

  1. Ultra-short channel GaN high electron mobility transistor-like...

    Office of Scientific and Technical Information (OSTI)

    based on the velocity-field dependence of two-dimensional electron gas (2-DEG) channel accounting for the ballistic electron acceleration and the inter-valley transfer. In...

  2. Huntington Resource Recovery Facility Biomass Facility | Open...

    Open Energy Info (EERE)

    Resource Recovery Facility Biomass Facility Jump to: navigation, search Name Huntington Resource Recovery Facility Biomass Facility Facility Huntington Resource Recovery Facility...

  3. Wheelabrator Sherman Energy Facility Biomass Facility | Open...

    Open Energy Info (EERE)

    Sherman Energy Facility Biomass Facility Jump to: navigation, search Name Wheelabrator Sherman Energy Facility Biomass Facility Facility Wheelabrator Sherman Energy Facility Sector...

  4. Growth and Band Offsets of Epitaxial Lanthanide Oxides on GaN...

    Office of Scientific and Technical Information (OSTI)

    M.T.T., 60 (6) (2012) 3 Jon Ihlefeld, Sandia National Laboratories Electronic Materials ... Undoped GaN Undoped AlGaN Doped AlGaN 2D Electron Gas Enhancement Mode (nominally ...

  5. Dislocation confinement in the growth of Na flux GaN on metalorganic...

    Office of Scientific and Technical Information (OSTI)

    Dislocation confinement in the growth of Na flux GaN on metalorganic chemical vapor deposition-GaN Citation Details In-Document Search Title: Dislocation confinement in the growth ...

  6. Low temperature thin film transistors with hollow cathode plasma-assisted atomic layer deposition based GaN channels

    SciTech Connect (OSTI)

    Bolat, S. E-mail: aokyay@ee.bilkent.edu.tr; Tekcan, B.; Ozgit-Akgun, C.; Biyikli, N.; Okyay, A. K. E-mail: aokyay@ee.bilkent.edu.tr

    2014-06-16

    We report GaN thin film transistors (TFT) with a thermal budget below 250?C. GaN thin films are grown at 200?C by hollow cathode plasma-assisted atomic layer deposition (HCPA-ALD). HCPA-ALD-based GaN thin films are found to have a polycrystalline wurtzite structure with an average crystallite size of 9.3?nm. TFTs with bottom gate configuration are fabricated with HCPA-ALD grown GaN channel layers. Fabricated TFTs exhibit n-type field effect characteristics. N-channel GaN TFTs demonstrated on-to-off ratios (I{sub ON}/I{sub OFF}) of 10{sup 3} and sub-threshold swing of 3.3?V/decade. The entire TFT device fabrication process temperature is below 250?C, which is the lowest process temperature reported for GaN based transistors, so far.

  7. Hybrid device based on GaN nanoneedles and MEH-PPV/PEDOT:PSS polymer

    SciTech Connect (OSTI)

    Shin, Min Jeong; Gwon, Dong-Oh; Lee, Chan-Mi; Lee, Gang Seok; Jeon, In-Jun; Ahn, Hyung Soo; Yi, Sam Nyung; Ha, Dong Han

    2015-08-15

    Highlights: • A hybrid device was demonstrated by using MEH-PPV, PEDOT:PSS, and GaN nanoneedles. • I–V curve of the hybrid device showed its rectification behaviour, similar to a diode. • EL peak originated by the different potential barriers at MEH-PPV and GaN interface. - Abstract: A hybrid device that combines the properties of organic and inorganic semiconductors was fabricated and studied. It incorporated poly[2-methoxy-5-(2-ethylhexyloxy)- 1,4-phenylenevinylene] (MEH-PPV) and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) as organic polymers and GaN nanoneedles as an inorganic semiconductor. Layers of the two polymers were spin coated on to the GaN nanoneedles. The one peak in the electroluminescence spectrum originated from the MEH-PPV layer owing to the different potential barriers of electrons and holes at its interface with the GaN nanoneedles. However, the photoluminescence spectrum showed peaks due to both GaN nanoneedles and MEH-PPV. Such hybrid structures, suitably developed, might be able to improve the efficiency of optoelectronic devices.

  8. ARM - Facility News Article

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

    Scanning Capability Added to Cloud Radar Bookmark and Share As a prelude to great things to come throughout the user facility, a new 95-gigahertz scanning W-band cloud radar was installed in late September at the ARM Mobile Facility deployment site in the Azores. This new radar joins the instrument suite that has been collecting data at the airport on Graciosa Island since May 2009. The added scanning capability provides 3D information about clouds that scientists need to improve climate models.

  9. Ashton Extended Facility

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

    Ashton Extended Facility Map

  10. Byron Extended Facility

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

    Byron Extended Facility Map

  11. Intrinsic polarization control in rectangular GaN nanowire lasers

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

    Li, Changyi; Liu, Sheng; Luk, Ting S.; Figiel, Jeffrey J.; Brener, Igal; Brueck, S. R. J.; Wang, George T.

    2016-02-01

    In this study, we demonstrate intrinsic, linearly polarized lasing from single GaN nanowires using cross-sectional shape control. A two-step top-down fabrication approach was employed to create straight nanowires with controllable rectangular cross-sections. A clear lasing threshold of 444kW/cm2 and a narrow spectral line width of 0.16 nm were observed under optical pumping at room temperature, indicating the onset of lasing. The polarization was along the short dimension (y-direction) of the nanowire due to the higher transverse confinement factors for y-polarized transverse modes resulting from the rectangular nanowire cross-section. The results show that cross-sectioned shape control can enable inherent control overmore » the polarization of nanowire lasers without additional environment requirements, such as placement onto lossy substrates.« less

  12. User Facilities

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

    User Facilities User Facilities User facility agreements allow Los Alamos partners and other entities to conduct research at our unique facilities. In 2011, LANL hosted more than 1,200 users at CINT, LANSCE, and NHMFL. Users came from across the DOE complex, from international academia, and from industrial companies from 45 states across the U.S. Unique world-class user facilities foster rich research opportunities Through its technology transfer efforts, LANL can implement user facility

  13. ARM - Facility News Article

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

    Sunphotometer to Obtain Additional Aerosol Data in Niamey Bookmark and Share Located nearby the AMF ground instruments, the sunphotometer, in the foreground, requires an unobstructed hemispheric view of the sky to obtain its measurements. In early August, a new Cimel sunphotometer (CSPHOT) was deployed at the ARM Mobile Facility site in Niamey, Niger, as part of the ongoing RADAGAST field campaign. The CSPHOT measures the solar and sky radiance at various wavelengths in the visible and

  14. ARM - Facility News Article

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

    April 30, 2010 [Data Announcements, Facility News] Tandem Differential Mobility Analyzer (TDMA) Data Available at the ARM Data Archive Bookmark and Share Dry samples are collected by the aerosol stack and transferred inside the Aerosol Observation System structure to the TDMA where they are exposed to humidity for growth rate sampling. For more details on how the TDMA works, see this schematic. Dry samples are collected by the aerosol stack and transferred inside the Aerosol Observation System

  15. ARM - Facility News Article

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

    10, 2010 [Facility News] Supporting Science at Summit Station, Greenland Bookmark and Share This month, an ARM micropulse lidar and ceilometer began collecting data from Summit Station in Greenland as part of the ICECAPS field campaign that runs through October 2014. Scientist Matthew Shupe joined colleagues on location to install the ICECAPS mobile laboratory, documenting their progress through his field blog. Great job, Matt! Visit the campaign website for more information

  16. ARM - Facility News Article

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

    August 31, 2008 [Facility News] Phase 2 of Orbiting Carbon Observatory Field Campaign Begins Bookmark and Share A camera, weather station, and sun tracker with a protective dome are located on the roof of the fully automated FTS mobile laboratory. Inside the shelter, the spectrometer receives the reflected solar beam from the sun tracker, while the main computer system operates all the instruments and acquires the data. A camera, weather station, and sun tracker with a protective dome are

  17. High active nitrogen flux growth of GaN by plasma assisted molecular beam epitaxy

    SciTech Connect (OSTI)

    McSkimming, Brian M. Speck, James S.; Chaix, Catherine

    2015-09-15

    In the present study, the authors report on a modified Riber radio frequency (RF) nitrogen plasma source that provides active nitrogen fluxes more than 30 times higher than those commonly used for plasma assisted molecular beam epitaxy (PAMBE) growth of gallium nitride (GaN) and thus a significantly higher growth rate than has been previously reported. GaN films were grown using N{sub 2} gas flow rates between 5 and 25 sccm while varying the plasma source's RF forward power from 200 to 600 W. The highest growth rate, and therefore the highest active nitrogen flux, achieved was ∼7.6 μm/h. For optimized growth conditions, the surfaces displayed a clear step-terrace structure with an average RMS roughness (3 × 3 μm) on the order of 1 nm. Secondary ion mass spectroscopy impurity analysis demonstrates oxygen and hydrogen incorporation of 1 × 10{sup 16} and ∼5 × 10{sup 17}, respectively. In addition, the authors have achieved PAMBE growth of GaN at a substrate temperature more than 150 °C greater than our standard Ga rich GaN growth regime and ∼100 °C greater than any previously reported PAMBE growth of GaN. This growth temperature corresponds to GaN decomposition in vacuum of more than 20 nm/min; a regime previously unattainable with conventional nitrogen plasma sources. Arrhenius analysis of the decomposition rate shows that samples with a flux ratio below stoichiometry have an activation energy greater than decomposition of GaN in vacuum while samples grown at or above stoichiometry have decreased activation energy. The activation energy of decomposition for GaN in vacuum was previously determined to be ∼3.1 eV. For a Ga/N flux ratio of ∼1.5, this activation energy was found to be ∼2.8 eV, while for a Ga/N flux ratio of ∼0.5, it was found to be ∼7.9 eV.

  18. MOBILITY AGREEMENT

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

    MOBILITY AGREEMENT I hereby acknowledge that, as a condition of my employment as a Criminal Investigator with the Department of Energy, Office of Inspector General, I may be required to relocate to an OIG office in another geographic location based on the needs of the organization. I understand that my failure to accept such a directed reassignment could be a basis for my separation from the service. _______________________________ Signature Date

  19. Facility Representatives

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2011-03-01

    This standard, DOE-STD-1063, Facility Representatives, defines the duties, responsibilities and qualifications for Department of Energy (DOE) Facility Representatives, based on facility hazard classification; risks to workers, the public, and the environment; and the operational activity level. This standard provides the guidance necessary to ensure that DOE’s hazardous nuclear and non-nuclear facilities have sufficient staffing of technically qualified facility representatives (FRs) to provide day-to-day oversight of contractor operations.

  20. User Facilities

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

    User Facilities User Facilities A new research frontier awaits! Our door is open, and we thrive on mutually beneficial partnerships and collaborations that drive innovations and new technologies. Unique world-class user facilities foster rich research opportunities Through its technology transfer efforts, Los Alamos National Laboratory can implement user facility agreements that allow its partners and other entities to conduct research at many of its unique facilities. While our largest user

  1. Nanostructural engineering of nitride nucleation layers for GaN substrate dislocation reduction.

    SciTech Connect (OSTI)

    Koleske, Daniel David; Lee, Stephen Roger; Lemp, Thomas Kerr; Coltrin, Michael Elliott; Cross, Karen Charlene; Thaler, Gerald

    2009-07-01

    With no lattice matched substrate available, sapphire continues as the substrate of choice for GaN growth, because of its reasonable cost and the extensive prior experience using it as a substrate for GaN. Surprisingly, the high dislocation density does not appear to limit UV and blue LED light intensity. However, dislocations may limit green LED light intensity and LED lifetime, especially as LEDs are pushed to higher current density for high end solid state lighting sources. To improve the performance for these higher current density LEDs, simple growth-enabled reductions in dislocation density would be highly prized. GaN nucleation layers (NLs) are not commonly thought of as an application of nano-structural engineering; yet, these layers evolve during the growth process to produce self-assembled, nanometer-scale structures. Continued growth on these nuclei ultimately leads to a fully coalesced film, and we show in this research program that their initial density is correlated to the GaN dislocation density. In this 18 month program, we developed MOCVD growth methods to reduce GaN dislocation densities on sapphire from 5 x 10{sup 8} cm{sup -2} using our standard delay recovery growth technique to 1 x 10{sup 8} cm{sup -2} using an ultra-low nucleation density technique. For this research, we firmly established a correlation between the GaN nucleation thickness, the resulting nucleation density after annealing, and dislocation density of full GaN films grown on these nucleation layers. We developed methods to reduce the nuclei density while still maintaining the ability to fully coalesce the GaN films. Ways were sought to improve the GaN nuclei orientation by improving the sapphire surface smoothness by annealing prior to the NL growth. Methods to eliminate the formation of additional nuclei once the majority of GaN nuclei were developed using a silicon nitride treatment prior to the deposition of the nucleation layer. Nucleation layer thickness was determined

  2. ORISE: Facilities

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

    ORISE Facilities Unique laboratories and training centers among the assets managed on behalf of the U.S. Department of Energy The Oak Ridge Institute for Science and Education (ORISE) is home to a number of on- and off-site facilities that support the U.S. Department of Energy's (DOE) science education and research mission. From on-site medical laboratories to radiation emergency medicine training facilities, ORISE facilities are helping to address national needs in the following areas:

  3. Science Facilities

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

    Facilities Science Facilities The focal point for basic and applied R&D programs with a primary focus on energy but also encompassing medical, biotechnology, high-energy physics, and advanced scientific computing programs. Center for Integrated Nanotechnologies» Dual Axis Radiographic Hydrodynamic Test Facility (DARHT)» Electron Microscopy Lab» Ion Beam Materials Lab» Isotope Production Facility» Los Alamos Neutron Science Center» Lujan Center» Matter-Radiation Interactions in

  4. Facility Safety

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1996-10-24

    Establishes facility safety requirements related to: nuclear safety design, criticality safety, fire protection and natural phenomena hazards mitigation.

  5. Facility Safety

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1995-11-16

    Establishes facility safety requirements related to: nuclear safety design, criticality safety, fire protection and natural phenomena hazards mitigation.

  6. Synthesis, morphology and optical properties of GaN and AlGaN semiconductor nanostructures

    SciTech Connect (OSTI)

    Kuppulingam, B. Singh, Shubra Baskar, K.

    2014-04-24

    Hexagonal Gallium Nitride (GaN) and Aluminum Gallium Nitride (AlGaN) nanoparticles were synthesized by sol-gel method using Ethylene Diamine Tetra Acetic acid (EDTA) complex route. Powder X-ray diffraction (PXRD) analysis confirms the hexagonal wurtzite structure of GaN and Al{sub 0.25}Ga{sub 0.75}N nanoparticles. Surface morphology and elemental analysis were carried out by Scanning Electron Microscope (SEM) and Energy Dispersive X-ray spectroscopy (EDX). The room temperature Photoluminescence (PL) study shows the near band edge emission for GaN at 3.35 eV and at 3.59 eV for AlGaN nanoparticles. The Aluminum (Al) composition of 20% has been obtained from PL emission around 345 nm.

  7. Wheelabrator Millbury Facility Biomass Facility | Open Energy...

    Open Energy Info (EERE)

    Facility Facility Wheelabrator Millbury Facility Sector Biomass Facility Type Municipal Solid Waste Location Worcester County, Massachusetts Coordinates 42.4096528, -71.8571331...

  8. Mobile workstation for decontamination and decommissioning operations

    SciTech Connect (OSTI)

    Whittaker, W.L.; Osborn, J.F.; Thompson, B.R.

    1993-10-01

    This project is an interdisciplinary effort to develop effective mobile worksystems for decontamination and decommissioning (D&D) of facilities within the DOE Nuclear Weapons Complex. These mobile worksystems will be configured to operate within the environmental and logistical constraints of such facilities and to perform a number of work tasks. Our program is designed to produce a mobile worksystem with capabilities and features that are matched to the particular needs of D&D work by evolving the design through a series of technological developments, performance tests and evaluations. The project has three phases. In this the first phase, an existing teleoperated worksystem, the Remote Work Vehicle (developed for use in the Three Mile Island Unit 2 Reactor Building basement), was enhanced for telerobotic performance of several D&D operations. Its ability to perform these operations was then assessed through a series of tests in a mockup facility that contained generic structures and equipment similar to those that D&D work machines will encounter in DOE facilities. Building upon the knowledge gained through those tests and evaluations, a next generation mobile worksystem, the RWV II, and a more advanced controller will be designed, integrated and tested in the second phase, which is scheduled for completion in January 1995. The third phase of the project will involve testing of the RWV II in the real DOE facility.

  9. Electrical and optical properties of carbon-doped GaN grown by MBE on MOCVD GaN templates using a CCl4 dopant source

    SciTech Connect (OSTI)

    Armitage, Rob; Yang, Qing; Feick, Henning; Park, Yeonjoon; Weber, Eicke R.

    2002-04-15

    Carbon-doped GaN was grown by plasma-assisted molecular-beam epitaxy using carbon tetrachloride vapor as the dopant source. For moderate doping mainly acceptors were formed, yielding semi-insulating GaN. However at higher concentrations p-type conductivity was not observed, and heavily doped films (>5 x 10{sup 20} cm{sup -3}) were actually n-type rather than semi-insulating. Photoluminescence measurements showed two broad luminescence bands centered at 2.2 and 2.9 eV. The intensity of both bands increased with carbon content, but the 2.2 eV band dominated in n-type samples. Intense, narrow ({approx}6 meV) donor-bound exciton peaks were observed in the semi-insulating samples.

  10. ARM - Facility News Article

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

    New Data Streams Available for ARM Mobile Facility Deployment Sites Bookmark and Share The pyeruc20isobX1.c1 datastream originates from data in a grid of points bordered by latitudes 34.300 and 42.539 and by longitudes -127.607 and -120.862; the RUC "bounding box." This area is indicated by the blue corner squares; purple dots indicate MOLTS stations, and green triangles indicate ECMWF stations. New climate datastreams are now available from Point Reyes National Seashore in California,

  11. Cooperating mobile robots

    DOE Patents [OSTI]

    Harrington, John J.; Eskridge, Steven E.; Hurtado, John E.; Byrne, Raymond H.

    2004-02-03

    A miniature mobile robot provides a relatively inexpensive mobile robot. A mobile robot for searching an area provides a way for multiple mobile robots in cooperating teams. A robotic system with a team of mobile robots communicating information among each other provides a way to locate a source in cooperation. A mobile robot with a sensor, a communication system, and a processor, provides a way to execute a strategy for searching an area.

  12. Beamlines & Facilities

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

    Imaging Group: Beamlines The X-ray Micrscopy and Imaging Group operates several beamlines and facilities. The bending magnet beamline (2-BM) entertaines 2 general user programs in...

  13. Tunnel-injection GaN quantum dot ultraviolet light-emitting diodes

    SciTech Connect (OSTI)

    Verma, Jai; Kandaswamy, Prem Kumar; Protasenko, Vladimir; Verma, Amit; Grace Xing, Huili; Jena, Debdeep

    2013-01-28

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

  14. Group-III nitride based high electron mobility transistor (HEMT) with barrier/spacer layer

    DOE Patents [OSTI]

    Chavarkar, Prashant; Smorchkova, Ioulia P.; Keller, Stacia; Mishra, Umesh; Walukiewicz, Wladyslaw; Wu, Yifeng

    2005-02-01

    A Group III nitride based high electron mobility transistors (HEMT) is disclosed that provides improved high frequency performance. One embodiment of the HEMT comprises a GaN buffer layer, with an Al.sub.y Ga.sub.1-y N (y=1 or y 1) layer on the GaN buffer layer. An Al.sub.x Ga.sub.1-x N (0.ltoreq.x.ltoreq.0.5) barrier layer on to the Al.sub.y Ga.sub.1-y N layer, opposite the GaN buffer layer, Al.sub.y Ga.sub.1-y N layer having a higher Al concentration than that of the Al.sub.x Ga.sub.1-x N barrier layer. A preferred Al.sub.y Ga.sub.1-y N layer has y=1 or y.about.1 and a preferred Al.sub.x Ga.sub.1-x N barrier layer has 0.ltoreq.x.ltoreq.0.5. A 2DEG forms at the interface between the GaN buffer layer and the Al.sub.y Ga.sub.1-y N layer. Respective source, drain and gate contacts are formed on the Al.sub.x Ga.sub.1-x N barrier layer. The HEMT can also comprising a substrate adjacent to the buffer layer, opposite the Al.sub.y Ga.sub.1-y N layer and a nucleation layer between the Al.sub.x Ga.sub.1-x N buffer layer and the substrate.

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

    SciTech Connect (OSTI)

    Vladimir Dmitriev

    2007-06-30

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

  16. Atmospheric Radiation Measurement Radiative Atmospheric Divergence using ARM Mobile

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

    Radiative Atmospheric Divergence using ARM Mobile Facility, GERB, and AMMA Stations (RADAGAST) Beginning in January 2006, the ARM Mobile Facility (AMF) began supporting RADAGAST to provide the first well-sampled direct esti- mates of the energy balance across the atmosphere. The experiment is part of an ongoing international study of the West African monsoon system and Saharan dust storms. Stationed outside the Niger Meteo- rological Office at the Niamey International Airport, the AMF is located

  17. Metal-interconnection-free integration of InGaN/GaN light emitting diodes with AlGaN/GaN high electron mobility transistors

    SciTech Connect (OSTI)

    Liu, Chao; Cai, Yuefei; Liu, Zhaojun; Ma, Jun; Lau, Kei May

    2015-05-04

    We report a metal-interconnection-free integration scheme for InGaN/GaN light emitting diodes (LEDs) and AlGaN/GaN high electron mobility transistors (HEMTs) by combining selective epi removal (SER) and selective epitaxial growth (SEG) techniques. SER of HEMT epi was carried out first to expose the bottom unintentionally doped GaN buffer and the sidewall GaN channel. A LED structure was regrown in the SER region with the bottom n-type GaN layer (n-electrode of the LED) connected to the HEMTs laterally, enabling monolithic integration of the HEMTs and LEDs (HEMT-LED) without metal-interconnection. In addition to saving substrate real estate, minimal interface resistance between the regrown n-type GaN and the HEMT channel is a significant improvement over metal-interconnection. Furthermore, excellent off-state leakage characteristics of the driving transistor can also be guaranteed in such an integration scheme.

  18. Facility Safety

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2005-12-22

    This Order establishes facility and programmatic safety requirements for Department of Energy facilities, which includes nuclear and explosives safety design criteria, fire protection, criticality safety, natural phenomena hazards mitigation, and the System Engineer Program. Cancels DOE O 420.1A. DOE O 420.1B Chg 1 issued 4-19-10.

  19. Facility Representatives

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2006-04-06

    REPLACED BY DOE-STD-1063 | SUPERSEDING DOE-STD-1063-2000 (MARCH 2000) The purpose of the DOE Facility Representative Program is to ensure that competent DOE staff personnel are assigned to oversee the day-to-day contractor operations at DOE’s hazardous nuclear and non-nuclear facilities.

  20. Facility Safety

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2012-12-04

    The Order establishes facility and programmatic safety requirements for DOE and NNSA for nuclear safety design criteria, fire protection, criticality safety, natural phenomena hazards (NPH) mitigation, and System Engineer Program. This Page Change is limited in scope to changes necessary to invoke DOE-STD-1104, Review and Approval of Nuclear Facility Safety Basis and Safety Design Basis Document, and revised DOE-STD-3009-2014, Preparation of Nonreactor Nuclear Facility Documented Safety Analysis as required methods. DOE O 420.1C Chg 1, dated 2-27-15, supersedes DOE O 420.1C.

  1. Influence of growth temperature and temperature ramps on deep level defect incorporation in m-plane GaN

    SciTech Connect (OSTI)

    Armstrong, A. M.; Kelchner, K.; Nakamura, S.; DenBaars, S. P.; Materials Department, University of California, Santa Barbara, California 93106 ; Speck, J. S.

    2013-12-02

    The dependence of deep level defect incorporation in m-plane GaN films grown by metal-organic chemical vapor deposition on bulk m-plane GaN substrates as a function of growth temperature (T{sub g}) and T{sub g} ramping method was investigated using deep level optical spectroscopy. Understanding the influence of T{sub g} on GaN deep level incorporation is important for InGaN/GaN multi-quantum well (MQW) light emitting diodes (LEDs) and laser diodes (LDs) because GaN quantum barrier (QB) layers are grown much colder than thin film GaN to accommodate InGaN QW growth. Deep level spectra of low T{sub g} (800?C) GaN films grown under QB conditions were compared to deep level spectra of high T{sub g} (1150?C) GaN. Reducing T{sub g}, increased the defect density significantly (>50) through introduction of emergent deep level defects at 2.09?eV and 2.9?eV below the conduction band minimum. However, optimizing growth conditions during the temperature ramp when transitioning from high to low T{sub g} substantially reduced the density of these emergent deep levels by approximately 40%. The results suggest that it is important to consider the potential for non-radiative recombination in QBs of LED or LD active regions, and tailoring the transition from high T{sub g} GaN growth to active layer growth can mitigate such non-radiative channels.

  2. Total Energy Facilities Biomass Facility | Open Energy Information

    Open Energy Info (EERE)

    Energy Facilities Biomass Facility Jump to: navigation, search Name Total Energy Facilities Biomass Facility Facility Total Energy Facilities Sector Biomass Facility Type...

  3. Gas Utilization Facility Biomass Facility | Open Energy Information

    Open Energy Info (EERE)

    Gas Utilization Facility Biomass Facility Jump to: navigation, search Name Gas Utilization Facility Biomass Facility Facility Gas Utilization Facility Sector Biomass Facility Type...

  4. Localized tip enhanced Raman spectroscopic study of impurity incorporated single GaN nanowire in the sub-diffraction limit

    SciTech Connect (OSTI)

    Patsha, Avinash E-mail: dhara@igcar.gov.in; Dhara, Sandip; Tyagi, A. K.

    2015-09-21

    The localized effect of impurities in single GaN nanowires in the sub-diffraction limit is reported using the study of lattice vibrational modes in the evanescent field of Au nanoparticle assisted tip enhanced Raman spectroscopy (TERS). GaN nanowires with the O impurity and the Mg dopants were grown by the chemical vapor deposition technique in the catalyst assisted vapor-liquid-solid process. Symmetry allowed Raman modes of wurtzite GaN are observed for undoped and doped nanowires. Unusually very strong intensity of the non-zone center zone boundary mode is observed for the TERS studies of both the undoped and the Mg doped GaN single nanowires. Surface optical mode of A{sub 1} symmetry is also observed for both the undoped and the Mg doped GaN samples. A strong coupling of longitudinal optical (LO) phonons with free electrons, however, is reported only in the O rich single nanowires with the asymmetric A{sub 1}(LO) mode. Study of the local vibration mode shows the presence of Mg as dopant in the single GaN nanowires.

  5. Facility Safety

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2002-05-20

    To establish facility safety requirements for the Department of Energy, including National Nuclear Security Administration. Cancels DOE O 420.1. Canceled by DOE O 420.1B.

  6. Facility Safety

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2005-12-22

    The order establishes facility and programmatic safety requirements for nuclear and explosives safety design criteria, fire protection, criticality safety, natural phenomena hazards (NPH) mitigation, and the System Engineer Program.Chg 1 incorporates the use of DOE-STD-1189-2008, Integration of Safety into the Design Process, mandatory for Hazard Category 1, 2 and 3 nuclear facilities. Cancels DOE O 420.1A.

  7. Facility Safety

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2013-06-21

    DOE-STD-1104 contains the Department's method and criteria for reviewing and approving nuclear facility's documented safety analysis (DSA). This review and approval formally document the basis for DOE, concluding that a facility can be operated safely in a manner that adequately protects workers, the public, and the environment. Therefore, it is appropriate to formally require implementation of the review methodology and criteria contained in DOE-STD-1104.

  8. Facility Safety

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2000-11-20

    The objective of this Order is to establish facility safety requirements related to: nuclear safety design, criticality safety, fire protection and natural phenomena hazards mitigation. The Order has Change 1 dated 11-16-95, Change 2 dated 10-24-96, and the latest Change 3 dated 11-22-00 incorporated. The latest change satisfies a commitment made to the Defense Nuclear Facilities Safety Board (DNFSB) in response to DNFSB recommendation 97-2, Criticality Safety.

  9. Working with SRNL - Our Facilities - Glovebox Facilities

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

    SRNL Our Facilities - Glovebox Facilities Govebox Facilities are sealed, protectively-lined compartments with attached gloves, allowing workers to safely handle dangerous materials...

  10. SLAC Accelerator Test Facilities

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

    FACET & TF Careers & Education Archived FACET User Facility Quick Launch About FACET & Test Facilities Expand About FACET & Test Facilities FACET & Test Facilities User Portal...

  11. MobileMatch App

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

    MobileMatch VolunteerMatch Mobile App MobileMatch is a mobile extension (app) to LANL's VolunteerMatch site that allows volunteers to search, sign up and track hours. Contact Giving Campaigns & Volunteering Debbi Wersonick Community Relations & Partnerships (505) 667-7870 Email Engage anytime, anywhere with this easy and intuitive tool! Using MobileMatch app is easy mobilematch-app Now LANL volunteers can search, sign up and track hours right on their mobile device. Get on the Volunteer

  12. Performance and breakdown characteristics of irradiated vertical power GaN P-i-N diodes

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

    King, M. P.; Armstrong, A. M.; Dickerson, J. R.; Vizkelethy, G.; Fleming, R. M.; Campbell, J.; Wampler, W. R.; Kizilyalli, I. C.; Bour, D. P.; Aktas, O.; et al

    2015-10-29

    Electrical performance and defect characterization of vertical GaN P-i-N diodes before and after irradiation with 2.5 MeV protons and neutrons is investigated. Devices exhibit increase in specific on-resistance following irradiation with protons and neutrons, indicating displacement damage introduces defects into the p-GaN and n- drift regions of the device that impact on-state device performance. The breakdown voltage of these devices, initially above 1700 V, is observed to decrease only slightly for particle fluence <; 1013 cm-2. Furthermore, the unipolar figure of merit for power devices indicates that while the on-resistance and breakdown voltage degrade with irradiation, vertical GaN P-i-Ns remainmore » superior to the performance of the best available, unirradiated silicon devices and on-par with unirradiated modern SiC-based power devices.« less

  13. Surfactant assisted growth of MgO films on GaN

    SciTech Connect (OSTI)

    Paisley, E. A.; Shelton, T. C.; Collazo, R.; Sitar, Z.; Maria, J.-P.; Christen, H. M.; Biegalski, M. D.; Mita, S.

    2012-08-27

    Thin epitaxial films of <111> oriented MgO on [0001]-oriented GaN were grown by molecular beam epitaxy and pulsed laser deposition using the assistance of a vapor phase surfactant. In both cases, surfactant incorporation enabled layer-by-layer growth and a smooth terminal surface by stabilizing the {l_brace}111{r_brace} rocksalt facet. Metal-insulator-semiconductor capacitor structures were fabricated on n-type GaN. A comparison of leakage current density for conventional and surfactant-assisted growth reveals a nearly 100 Multiplication-Sign reduction in leakage current density for the surfactant-assisted samples. These data verify numerous predictions regarding the role of H-termination in regulating the habit of rocksalt crystals.

  14. Anisotropy of two-photon absorption and free-carrier effect in nonpolar GaN

    SciTech Connect (OSTI)

    Fang, Yu; Zhou, Feng; Yang, Junyi; Wu, Xingzhi; Xiao, Zhengguo; Li, Zhongguo; Song, Yinglin

    2015-03-30

    We reported a systematic study about the anisotropic optical nonlinearities in bulk m-plane and a-plane GaN crystals by Z-scan and pump-probe with phase object methods under picosecond at 532 nm. The two-photon absorption coefficient, which was measured as a function of polarization angle, exhibited oscillation curves with a period of π/2, indicating a highly polarized optical third-order nonlinearity in both nonpolar GaN samples. Furthermore, free-carrier absorption revealed stronger hole-related absorption for E⊥c than for E//c probe polarization. In contrast, free-carrier refraction was found almost isotropic due to electron-related refraction in the isotropic conduction bands.

  15. Catalyst and its diameter dependent growth kinetics of CVD grown GaN nanowires

    SciTech Connect (OSTI)

    Samanta, Chandan [Department of Physics, Indian Institute of Technology Kanpur (India)] [Department of Physics, Indian Institute of Technology Kanpur (India); Chander, D. Sathish [Department of Physics, Indian Institute of Technology Kanpur (India) [Department of Physics, Indian Institute of Technology Kanpur (India); Department of Mechanical Engineering, Indian Institute of Technology Kanpur (India); Ramkumar, J. [Department of Mechanical Engineering, Indian Institute of Technology Kanpur (India)] [Department of Mechanical Engineering, Indian Institute of Technology Kanpur (India); Dhamodaran, S., E-mail: kdams2003@gmail.com [Department of Physics, Indian Institute of Technology Kanpur (India)

    2012-04-15

    Graphical abstract: GaN nanowires with controlled diameter and aspect ratio has been grown using a simple CVD technique. The growth kinetics of CVD grown nanowires investigated in detail for different catalysts and their diameters. A critical diameter important to distinguish the growth regimes has been discussed in detail. The results are important which demonstrates the growth of diameter and aspect ratio controlled GaN nanowires and also understand their growth kinetics. Highlights: Black-Right-Pointing-Pointer Controlled diameter and aspect ratio of GaN nanowires achieved in simple CVD reactor. Black-Right-Pointing-Pointer Nanowire growth kinetics for different catalyst and its diameters were understood. Black-Right-Pointing-Pointer Adatoms vapor pressure inside reactor plays a crucial role in growth kinetics. Black-Right-Pointing-Pointer Diffusion along nanowire sidewalls dominate for gold and nickel catalysts. Black-Right-Pointing-Pointer Gibbs-Thomson effect dominates for palladium catalyst. -- Abstract: GaN nanowires were grown using chemical vapor deposition with controlled aspect ratio. The catalyst and catalyst-diameter dependent growth kinetics is investigated in detail. We first discuss gold catalyst diameter dependent growth kinetics and subsequently compare with nickel and palladium catalyst. For different diameters of gold catalyst there was hardly any variation in the length of the nanowires but for other catalysts with different diameter a strong length variation of the nanowires was observed. We calculated the critical diameter dependence on adatoms pressure inside the reactor and inside the catalytic particle. This gives an increasing trend in critical diameter as per the order gold, nickel and palladium for the current set of experimental conditions. Based on the critical diameter, with gold and nickel catalyst the nanowire growth was understood to be governed by limited surface diffusion of adatoms and by Gibbs-Thomson effect for the palladium

  16. Hafnium nitride buffer layers for growth of GaN on silicon

    DOE Patents [OSTI]

    Armitage, Robert D.; Weber, Eicke R.

    2005-08-16

    Gallium nitride is grown by plasma-assisted molecular-beam epitaxy on (111) and (001) silicon substrates using hafnium nitride buffer layers. Wurtzite GaN epitaxial layers are obtained on both the (111) and (001) HfN/Si surfaces, with crack-free thickness up to 1.2 {character pullout}m. However, growth on the (001) surface results in nearly stress-free films, suggesting that much thicker crack-free layers could be obtained.

  17. Tandem mobile robot system

    DOE Patents [OSTI]

    Buttz, James H.; Shirey, David L.; Hayward, David R.

    2003-01-01

    A robotic vehicle system for terrain navigation mobility provides a way to climb stairs, cross crevices, and navigate across difficult terrain by coupling two or more mobile robots with a coupling device and controlling the robots cooperatively in tandem.

  18. Ion mobility sensor system

    DOE Patents [OSTI]

    Xu, Jun; Watson, David B.; Whitten, William B.

    2013-01-22

    An ion mobility sensor system including an ion mobility spectrometer and a differential mobility spectrometer coupled to the ion mobility spectrometer. The ion mobility spectrometer has a first chamber having first end and a second end extending along a first direction, and a first electrode system that generates a constant electric field parallel to the first direction. The differential mobility spectrometer includes a second chamber having a third end and a fourth end configured such that a fluid may flow in a second direction from the third end to the fourth end, and a second electrode system that generates an asymmetric electric field within an interior of the second chamber. Additionally, the ion mobility spectrometer and the differential mobility spectrometer form an interface region. Also, the first end and the third end are positioned facing one another so that the constant electric field enters the third end and overlaps the fluid flowing in the second direction.

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

    SciTech Connect (OSTI)

    Shi Meng; Chinchore, Abhijit; Wang Kangkang; Mandru, Andrada-Oana; Liu Yinghao; Smith, Arthur R.

    2012-09-01

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

  20. Analysis of the carbon-related 'blue' luminescence in GaN

    SciTech Connect (OSTI)

    Armitage, R.; Yang, Q.; Weber, E.R.

    2004-09-24

    The properties of a broad 2.86 eV photoluminescence band in carbon-doped GaN were studied as a function of C-doping level, temperature, and excitation density. The results are consistent with a C{sub Ga}-C{sub N} deep donor-deep acceptor recombination mechanism as proposed by Seager et al. For GaN:C grown by molecular-beam epitaxy (MBE) the 2.86 eV band is observed in Si co-doped layers exhibiting high n-type conductivity as well as in semi-insulating material. For low excitation density (4 W/cm{sup 2}) the 2.86 eV band intensity decreases as a function of cw-laser exposure time over a period of many minutes. The transient behavior is consistent with a model based on carrier diffusion and charge trapping-induced Coulomb barriers. The temperature dependence of the blue luminescence below 150 K was different for carbon-contaminated GaN grown by metalorganic vapor phase epitaxy (MOVPE) compared to C-doped MBE GaN.

  1. Theoretical and experimental study of dynamics of photoexcited carriers in GaN

    SciTech Connect (OSTI)

    Shishehchi, Sara; Bellotti, Enrico; Rudin, Sergey; Garrett, Gregory A.; Wraback, Michael

    2013-12-21

    We present a theoretical and experimental study of the sub-picosecond dynamics of photo-excited carriers in GaN. In the theoretical model, interaction with an external ultrafast laser pulse is treated coherently and to account for the scattering mechanisms and dephasing processes, a generalized Monte-Carlo simulation is used. The scattering mechanisms included are carrier interactions with polar optical phonons and acoustic phonons, and carrier-carrier Coulomb interactions. We study the effect of different scattering mechanisms on the carrier densities. In the case that the excitation energy satisfies the threshold for polar optical scattering, phonon contribution is the dominant process in relaxing the system, otherwise, carrier-carrier mechanism is dominant. Furthermore, we present the temperature and pulse power dependent normalized luminescence intensity. The results are presented over a range of temperatures, electric field, and excitation energy of the laser pulse. For comparison, we also report the experimental time-resolved photoluminescence studies on GaN samples. There is a good agreement between the simulation and experiment in normalized luminescence intensity results. Therefore, we show that we can explain the dynamics of the photo-excited carriers in GaN by including only carrier-carrier and carrier-phonon interactions and a relatively simple two-band electronic structure model.

  2. Vertical GaN power diodes with a bilayer edge termination

    SciTech Connect (OSTI)

    Dickerson, Jeramy R.; Allerman, Andrew A.; Bryant, Benjamin N.; Fischer, Arthur J.; King, Michael P.; Moseley, Michael W.; Armstrong, Andrew M.; Kaplar, Robert J.; Kizilyalli, Isik C.; Aktas, Ozgur; Wierer, Jr., Jonathan J.

    2015-12-07

    Vertical GaN power diodes with a bilayer edge termination (ET) are demonstrated. The GaN p-n junction is formed on a low threading dislocation defect density (104 - 105 cm-2) GaN substrate, and has a 15-μm-thick n-type drift layer with a free carrier concentration of 5 × 1015 cm-3. The ET structure is formed by N implantation into the p+-GaN epilayer just outside the p-type contact to create compensating defects. The implant defect profile may be approximated by a bilayer structure consisting of a fully compensated layer near the surface, followed by a 90% compensated (p) layer near the n-type drift region. These devices exhibit avalanche breakdown as high as 2.6 kV at room temperature. In addition simulations show that the ET created by implantation is an effective way to laterally distribute the electric field over a large area. This increases the voltage at which impact ionization occurs and leads to the observed higher breakdown voltages.

  3. Vertical GaN power diodes with a bilayer edge termination

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

    Dickerson, Jeramy R.; Allerman, Andrew A.; Bryant, Benjamin N.; Fischer, Arthur J.; King, Michael P.; Moseley, Michael W.; Armstrong, Andrew M.; Kaplar, Robert J.; Kizilyalli, Isik C.; Aktas, Ozgur; et al

    2015-12-07

    Vertical GaN power diodes with a bilayer edge termination (ET) are demonstrated. The GaN p-n junction is formed on a low threading dislocation defect density (104 - 105 cm-2) GaN substrate, and has a 15-μm-thick n-type drift layer with a free carrier concentration of 5 × 1015 cm-3. The ET structure is formed by N implantation into the p+-GaN epilayer just outside the p-type contact to create compensating defects. The implant defect profile may be approximated by a bilayer structure consisting of a fully compensated layer near the surface, followed by a 90% compensated (p) layer near the n-type driftmore » region. These devices exhibit avalanche breakdown as high as 2.6 kV at room temperature. In addition simulations show that the ET created by implantation is an effective way to laterally distribute the electric field over a large area. This increases the voltage at which impact ionization occurs and leads to the observed higher breakdown voltages.« less

  4. Mobile Technology Management

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2014-05-15

    The order establishes requirements, assigns responsibilities, and provides guidance for federal mobile technology management and employee use of both government furnished and personally-owned mobile devices within DOE and NNSA. Establishes requirements for use of User Agreements to govern mobile devices used for official duties. Does not cancel other directives.

  5. Facility Safety

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2012-12-04

    The Order establishes facility and programmatic safety requirements for DOE and NNSA for nuclear safety design criteria, fire protection, criticality safety, natural phenomena hazards (NPH) mitigation, and System Engineer Program. Cancels DOE O 420.1B, DOE G 420.1-2 and DOE G 420.1-3.

  6. Nuclear Facilities

    Broader source: Energy.gov [DOE]

    The nuclear sites list and map shows how DOE nuclear operations are mostly divided between nuclear weapons stockpile maintenance, research and environmental cleanup. The operations are performed within several different facilities supporting nuclear reactor operations, nuclear research, weapons disassembly, maintenance and testing, hot cell operations, nuclear material storage and processing and waste disposal.

  7. Facility Safety

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1995-10-13

    Establishes facility safety requirements related to: nuclear safety design, criticality safety, fire protection and natural phenomena hazards mitigation. Cancels DOE 5480.7A, DOE 5480.24, DOE 5480.28 and Division 13 of DOE 6430.1A. Canceled by DOE O 420.1A.

  8. Beam Test Facility

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

    Beam Test Facility Beam Test Facility Print Tuesday, 20 October 2009 09:36 Coming Soon

  9. Metro Methane Recovery Facility Biomass Facility | Open Energy...

    Open Energy Info (EERE)

    Methane Recovery Facility Biomass Facility Jump to: navigation, search Name Metro Methane Recovery Facility Biomass Facility Facility Metro Methane Recovery Facility Sector Biomass...

  10. Ion mobility sensor

    DOE Patents [OSTI]

    Koo, Jackson C.; Yu, Conrad M.

    2005-08-23

    An ion mobility sensor which can detect both ion and molecules simultaneously. Thus, one can measure the relative arrival times between various ions and molecules. Different ions have different mobility in air, and the ion sensor enables measurement of ion mobility, from which one can identify the various ions and molecules. The ion mobility sensor which utilizes a pair of glow discharge devices may be designed for coupling with an existing gas chromatograph, where various gas molecules are already separated, but numbers of each kind of molecules are relatively small, and in such cases a conventional ion mobility sensor cannot be utilized.

  11. Energize Mobile | Open Energy Information

    Open Energy Info (EERE)

    Web Application Link: www.tendrilinc.comenergy-providersapplicationenergize Cost: Free Energize Mobile Screenshot References: Tendril1 Logo: Energize Mobile This...

  12. Spectroscopic and magnetic properties of Mn doped GaN epitaxial films grown by plasma assisted molecular beam epitaxy

    SciTech Connect (OSTI)

    Vidyasagar, R.; Lin, Y.-T.; Tu, L.-W.

    2012-12-15

    Graphical abstract: We report here that micro-Raman scattering spectrum for Mn doped GaN thin film has displayed a new peak manifested at 578 cm{sup −1}, by which it is attributed to interior LVM originated by the incorporation of Mn ions in place of Ga sites. Mn doped GaN thin film also showed the typical negative magnetoresistance up to ∼50 K, revealing that the film showed magnetic ordering of spins below 50 K. Display Omitted Highlights: ► GaN and Mn doped GaN single phase wurtzite structures grown by PAMBE. ► The phase purity of the epilayers investigated by HRXRD, HRSEM and EDX. ► The red shift in near band edge emission has been observed using micro-PL. ► A new peak related LVM at 578 cm{sup −1} in micro-Raman scattering measurements confirmed Mn doped into GaN. ► Negative-magnetoresistance investigations have showed that the film has T{sub c} < 50 K. -- Abstract: Spectroscopic and magnetic properties of Mn doped GaN, and GaN epitaxial films have been investigated by employing micro-photoluminescence, micro-Raman, and temperature dependent magneto-resistance measurements. The HR-XRD profiles have shown that the epitaxial films are in hexagonal wurtzite structures. Morphology and composition of the films have been examined by field emission scanning electron microscopy, and energy-dispersive X-ray analysis. Micro-photoluminescence spectrum displayed a dominant near band edge emission at 362 nm, which is assigned to near band edge transition within the hexagonal structure of GaN. Raman scattering profiles showed a new vibrational mode at 578 cm{sup −1}, which is attributed to the vacancy-related local vibrational mode of Mn occupying the Ga site. Temperature dependent negative magnetoresistance measurements provide a direct evidence of magnetic ordering below 50 K for the Mn doped GaN thin film.

  13. Multicycle rapid thermal annealing optimization of Mg-implanted GaN: Evolution of surface, optical, and structural properties

    SciTech Connect (OSTI)

    Greenlee, Jordan D.; Feigelson, Boris N.; Anderson, Travis J.; Hite, Jennifer K.; Mastro, Michael A.; Eddy, Charles R.; Hobart, Karl D.; Kub, Francis J.; Tadjer, Marko J.

    2014-08-14

    The first step of a multi-cycle rapid thermal annealing process was systematically studied. The surface, structure, and optical properties of Mg implanted GaN thin films annealed at temperatures ranging from 900 to 1200?C were investigated by Raman spectroscopy, photoluminescence, UV-visible spectroscopy, atomic force microscopy, and Nomarski microscopy. The GaN thin films are capped with two layers of in-situ metal organic chemical vapor deposition -grown AlN and annealed in 24 bar of N{sub 2} overpressure to avoid GaN decomposition. The crystal quality of the GaN improves with increasing annealing temperature as confirmed by UV-visible spectroscopy and the full widths at half maximums of the E{sub 2} and A{sub 1} (LO) Raman modes. The crystal quality of films annealed above 1100?C exceeds the quality of the as-grown films. At 1200?C, Mg is optically activated, which is determined by photoluminescence measurements. However, at 1200?C, the GaN begins to decompose as evidenced by pit formation on the surface of the samples. Therefore, it was determined that the optimal temperature for the first step in a multi-cycle rapid thermal anneal process should be conducted at 1150?C due to crystal quality and surface morphology considerations.

  14. Utilization of native oxygen in Eu(RE)-doped GaN for enabling device compatibility in optoelectronic applications

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

    Mitchell, Brandon; Timmerman, D.; Poplawsky, Jonathan D.; Zhu, W.; Lee, D.; Wakamatsu, R.; Takatsu, J.; Matsuda, M.; Guo, Wei; Lorenz, K.; et al

    2016-01-04

    The detrimental influence of oxygen on the performance and reliability of V/III nitride based devices is well known. However, the influence of oxygen on the nature of the incorporation of other co-dopants, such as rare earth ions, has been largely overlooked in GaN. Here, we report the first comprehensive study of the critical role that oxygen has on Eu in GaN, as well as atomic scale observation of diffusion and local concentration of both atoms in the crystal lattice. We find that oxygen plays an integral role in the location, stability, and local defect structure around the Eu ions thatmore » were doped into the GaN host. Although the availability of oxygen is essential for these properties, it renders the material incompatible with GaN-based devices. However, the utilization of the normally occurring oxygen in GaN is promoted through structural manipulation, reducing its concentration by 2 orders of magnitude, while maintaining both the material quality and the favorable optical properties of the Eu ions. Furthermore, these findings open the way for full integration of RE dopants for optoelectronic functionalities in the existing GaN platform.« less

  15. Facility Type!

    Office of Legacy Management (LM)

    ITY: --&L~ ----------- srct-r~ -----------~------~------- if yee, date contacted ------------- cl Facility Type! i I 0 Theoretical Studies Cl Sample 84 Analysis ] Production 1 Diepasal/Storage 'YPE OF CONTRACT .--------------- 1 Prime J Subcontract&- 1 Purchase Order rl i '1 ! Other information (i.e., ---------~---~--~-------- :ontrait/Pirchaee Order # , I C -qXlJ- --~-------~~-------~~~~~~ I I ~~~---~~~~~~~T~~~ FONTRACTING PERIODi IWNERSHIP: ,I 1 AECIMED AECMED GOVT GOUT &NTtiAC+OR

  16. Research Facilities | NREL

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

    Research Facilities Our state-of-the-art facilities are available to industry entrepreneurs, engineers, scientists, and universities for researching and developing their energy technologies. Our researchers and technicians who operate these labs and facilities are ready to work with you and share their expertise. Alphabetical Listings Laboratories Test and User Facilities Popular Facilities Energy Systems Integration Facility Integrated Biorefinery Research Facility Process Development

  17. Properties of radio-frequency-sputter-deposited GaN films in a nitrogen/hydrogen mixed gas

    SciTech Connect (OSTI)

    Miyazaki, Takayuki; Takada, Kouhei; Adachi, Sadao; Ohtsuka, Kohji

    2005-05-01

    GaN films have been deposited by reactive sputtering in nitrogen gas at pressures from 0.08 to 2.70 Pa with and without the addition of hydrogen gas. X-ray diffraction (XRD), Fourier transform infrared (FTIR), optical absorption, and photoluminescence (PL) spectroscopy have been used to characterize the sputter-deposited GaN films. The XRD pattern reveals that the GaN films deposited in nitrogen gas at pressures lower than 0.53 Pa are polycrystals with the (0001) texture ({alpha}-GaN), while those deposited at or above 1.07 Pa display mixed crystalline orientations or an amorphous-like nature. The GaN:H films deposited in nitrogen/hydrogen mixed gas, on the other hand, show an amorphous or amorphous-like nature. The FTIR spectra indicate that the GaN:H films show peaks arising from hydrogen-related bonds at {approx}1000 and {approx}3200 cm{sup -1}, in addition to the GaN absorption band at {approx}555 cm{sup -1}. The optical absorption spectra at 300 K indicate the fundamental absorption edges at {approx}3.38 and {approx}3.7 eV for the highly oriented {alpha}-GaN and amorphous GaN:H films, respectively. PL emission has been observed from sputter-deposited {alpha}-GaN films at temperatures below 100 K. The GaN:H films also show strong band-edge and donor-acceptor pair emissions. The PL emission in the GaN:H film may arise from crystalline GaN particles embedded in the amorphous GaN matrix.

  18. Fundamental Bulk/Surface Structure Photoactivity Relationships of Supported (Rh2-yCryO3)/GaN Photocatalysts

    SciTech Connect (OSTI)

    Phivilay, Somphonh; Roberts, Charles; Puretzky, Alexander A; Domen, Kazunari Domen; Wachs, Israel

    2013-01-01

    ABSTRACT. The supported (Rh2-yCryO3)/GaN photocatalyst was examined as a model nitride photocatalyst system to assist in the development of fundamental structure photoactivity relationships for UV activated water splitting. Surface characterization of the outermost surface layers by High Sensitivity-LEIS and High Resolution-XPS revealed for the first time that the GaN support consists of a GaOx outermost surface layer and a thin film of GaOxNy in the surface region. HR-XPS also demonstrates that the supported (Rh2-yCryO3) mixed oxide nanoparticles (NPs) exclusively consist of Cr+3 and Rh+3 cations and are surface enriched for the supported (Rh2-yCryO3)/GaN photocatalyst. Bulk analysis by Raman and UV-vis spectroscopy show that the bulk molecular and electronic structures, respectively, of the GaN support are not perturbed by the deposition of the (Rh2-yCryO3) mixed oxide NPs. The function of the GaN bulk lattice is to generate photoexcited electrons/holes, with the electrons harnessed by the surface Rh+3 sites for evolution of H2 and the holes trapped at the Ga oxide/oxynitride surface sites for splitting of water and evolving O2. These new structure-photoactivity relationships for supported (Rh2-yCryO3)/GaN also extend to the best performing visible light activated supported (Rh2-yCryO3)/(Ga1-xZnx)(N1-xOx) photocatalyst.

  19. NREL: Research Facilities - Webmaster

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

    Your name: Your email address: Your message: Send Message Printable Version Research Facilities Home Laboratories Test & User Facilities Laboratories & Facilities by Technology...

  20. Facilities | Bioenergy | NREL

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

    Facilities At NREL's state-of-the-art bioenergy research facilities, researchers design ... facility to develop, test, evaluate, and demonstrate bioenergy processes and technologies. ...

  1. Research Facility,

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

    Delivering the Data As a general condition for use of the ARM Climate Research Facility, users are required to include their data in the ARM Data Archive. All data acquired must be of sufficient quality to be useful and must be documented such that users will be able to clearly understand the meaning and organization of the data. Final, quality-assured data sets are stored in the Data Archive and are freely accessible to the general scientific community. Upon conclusion of the field campaign,

  2. Heavy Mobile Equipment Mechanic

    Broader source: Energy.gov [DOE]

    Join the Bonneville Power Administration (BPA) for a challenging and rewarding career, while working, living, and playing in the Pacific Northwest. The Heavy Mobile Equipment Mechanic (HMEM)...

  3. Mobile Ice Nucleus Spectrometer

    SciTech Connect (OSTI)

    Kulkarni, Gourihar R.; Kok, G. L.

    2012-05-07

    This first year report presents results from a computational fluid dynamics (CFD) study to assess the flow and temperature profiles within the mobile ice nucleus spectrometer.

  4. Mobile Technology Management

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2013-11-21

    The directive will ensure that federal organizations and employees within the Department can use mobile technology to support mission requirements in a safe and secure manner.

  5. Electroreflectance study of the effect of {gamma} radiation on the optical properties of epitaxial GaN films

    SciTech Connect (OSTI)

    Belyaev, A. E.; Klyui, N. I. Konakova, R. V.; Lukyanov, A. N.; Danilchenko, B. A.; Sveshnikov, J. N.; Klyui, A. N.

    2012-03-15

    Experimental data on the electroreflectance spectra of {gamma}-irradiated epitaxial GaN films on sapphire are reported. The irradiation doses are 10{sup 5}-2 Multiplication-Sign 10{sup 6} rad. The theoretical electroreflectance spectra calculated on the basis of a model of three types of transitions are in agreement with experimental data with reasonable accuracy. The energies and broadenings of the transitions derived in the context of the model give grounds to infer that, in the GaN films, there are internal stresses dependent on the {gamma}-irradiation dose.

  6. Harrisburg Facility Biomass Facility | Open Energy Information

    Open Energy Info (EERE)

    2006 Database Retrieved from "http:en.openei.orgwindex.php?titleHarrisburgFacilityBiomassFacility&oldid397545" Feedback Contact needs updating Image needs updating...

  7. Brookhaven Facility Biomass Facility | Open Energy Information

    Open Energy Info (EERE)

    2006 Database Retrieved from "http:en.openei.orgwindex.php?titleBrookhavenFacilityBiomassFacility&oldid397235" Feedback Contact needs updating Image needs updating...

  8. Support - Facilities - Radiation Effects Facility / Cyclotron...

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

    During experiments at the Radiation Effects Facility users are assisted by the experienced ... shops are available to the users of the Radiation Effects Facility for design, ...

  9. Radiation Effects Facility - Facilities - Cyclotron Institute

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

    Radiation Effects Facility Typical DUT(device under test) set-up at the end of the Radiation Effects beamline. The Radiation Effects Facility is available for commercial, ...

  10. Nanoscale size dependence parameters on lattice thermal conductivity of Wurtzite GaN nanowires

    SciTech Connect (OSTI)

    Mamand, S.M.; Omar, M.S.; Muhammad, A.J.

    2012-05-15

    Graphical abstract: Temperature dependence of calculated lattice thermal conductivity of Wurtzite GaN nanowires. Highlights: Black-Right-Pointing-Pointer A modified Callaway model is used to calculate lattice thermal conductivity of Wurtzite GaN nanowires. Black-Right-Pointing-Pointer A direct method is used to calculate phonon group velocity for these nanowires. Black-Right-Pointing-Pointer 3-Gruneisen parameter, surface roughness, and dislocations are successfully investigated. Black-Right-Pointing-Pointer Dislocation densities are decreases with the decrease of wires diameter. -- Abstract: A detailed calculation of lattice thermal conductivity of freestanding Wurtzite GaN nanowires with diameter ranging from 97 to 160 nm in the temperature range 2-300 K, was performed using a modified Callaway model. Both longitudinal and transverse modes are taken into account explicitly in the model. A method is used to calculate the Debye and phonon group velocities for different nanowire diameters from their related melting points. Effect of Gruneisen parameter, surface roughness, and dislocations as structure dependent parameters are successfully used to correlate the calculated values of lattice thermal conductivity to that of the experimentally measured curves. It was observed that Gruneisen parameter will decrease with decreasing nanowire diameters. Scattering of phonons is assumed to be by nanowire boundaries, imperfections, dislocations, electrons, and other phonons via both normal and Umklapp processes. Phonon confinement and size effects as well as the role of dislocation in limiting thermal conductivity are investigated. At high temperatures and for dislocation densities greater than 10{sup 14} m{sup -2} the lattice thermal conductivity would be limited by dislocation density, but for dislocation densities less than 10{sup 14} m{sup -2}, lattice thermal conductivity would be independent of that.

  11. Impact of the GaN nanowire polarity on energy harvesting

    SciTech Connect (OSTI)

    Gogneau, Noelle Galopin, Elisabeth; Guilet, Stephane; Travers, Laurent; Harmand, Jean-Christophe; Chrétien, Pascal; Houzé, Frédéric

    2014-05-26

    We investigate the piezoelectric generation properties of GaN nanowires (NWs) by atomic force microscopy equipped with a Resiscope module for electrical measurements. By correlating the topography profile of the NWs with the recorded voltage peaks generated by these nanostructures in response to their deformation, we demonstrate the influence of their polarity on the rectifying behavior of the Schottky diode formed between the NWs and the electrode of measurement. These results establish that the piezo-generation mechanism crucially depends on the structural characteristics of the NWs.

  12. Kent County Waste to Energy Facility Biomass Facility | Open...

    Open Energy Info (EERE)

    County Waste to Energy Facility Biomass Facility Jump to: navigation, search Name Kent County Waste to Energy Facility Biomass Facility Facility Kent County Waste to Energy...

  13. Stockton Regional Water Control Facility Biomass Facility | Open...

    Open Energy Info (EERE)

    Stockton Regional Water Control Facility Biomass Facility Jump to: navigation, search Name Stockton Regional Water Control Facility Biomass Facility Facility Stockton Regional...

  14. Manufacturing Demonstration Facility

    Energy Savers [EERE]

    of Energy Manufacturing Demonstration Facility DOE Advanced Manufacturing Office Merit Review Craig Blue Director, Manufacturing Demonstration Facility Energy and ...

  15. Enhanced UV detection by non-polar epitaxial GaN films

    SciTech Connect (OSTI)

    Mukundan, Shruti; Chandan, Greeshma; Mohan, Lokesh; Krupanidhi, S. B.; Roul, Basanta; Shetty, Arjun

    2015-12-15

    Nonpolar a-GaN (11-20) epilayers were grown on r-plane (1-102) sapphire substrates using plasma assisted molecular beam epitaxy. High resolution x-ray diffractometer confirmed the orientation of the grown film. Effect of the Ga/N ratio on the morphology and strain of a-GaN epilayers was compared and the best condition was obtained for the nitrogen flow of 1 sccm. Atomic force microscopy was used to analyze the surface morphology while the strain in the film was quantitatively measured using Raman spectroscopy and qualitatively analyzed by reciprocal space mapping technique. UV photo response of a-GaN film was measured after fabricating a metal-semiconductor-metal structure over the film with gold metal. The external quantum efficiency of the photodetectors fabricated in the (0002) polar and (11-20) nonpolar growth directions were compared in terms of responsivity and nonpolar GaN showed the best sensitivity at the cost of comparatively slow response time.

  16. Surfactant assisted growth of MgO films on GaN

    SciTech Connect (OSTI)

    Paisley, Elisibeth A.; Shelton, T C; Mita, S; Gaddy, Brian E.; Irving, D L; Christen, Hans M; Sitar, Z; Biegalski, Michael D; Maria, Jon Paul

    2012-01-01

    Thin epitaxial films of <111> oriented MgO on [0001]-oriented GaN were grown by molecular beam epitaxy (MBE) and pulsed laser deposition (PLD) using the assistance of a vapor phase surfactant. In both cases, surfactant incorporation enabled layer-by-layer growth and a smooth terminal surface due to stabilizing the {111} rocksalt facet. MBE growth of MgO in water terminates after several monolayers, and is attributed to saturation of surface active sites needed to facilitate the Mg oxidation reaction. MgO films prepared by PLD grow continuously, this occurs due to the presence of excited oxidizing species in the laser plasma eliminate the need for catalytic surface sites. Metal-insulator-semiconductor capacitor structures were fabricated on n-type GaN. A comparison of leakage current density for conventional and surfactant-assisted growth reveals a nearly two order of magnitude reduction in leakage current density for the smoother surfactant-assisted samples. Collectively, these data verify numerous predictions and calculations regarding the role of H-termination in regulating the habit of MgO crystals.

  17. The effect of N-polar GaN domains as Ohmic contacts

    SciTech Connect (OSTI)

    Xie, J.; Mita, S.; Collazo, R.; Rice, A.; Tweedie, J.; Sitar, Z.

    2010-09-20

    Transfer line method measurements revealed that if the Ohmic contact regions were replaced by N-polar GaN, the contact resistance could be reduced from 0.71 {Omega} mm (or {rho}{sub c}=4x10{sup -6} {Omega} cm{sup 2}) to 0.24 {Omega} mm for a {approx}200 nm thick Si-doped GaN layer. The reduction in contact resistance was largely due to the {approx}10{sup 19} cm{sup -3} free carriers in N-polar source/drain regions as measured by Hall effect. Secondary ion mass spectroscopy confirmed that oxygen doping in the N-polar region was more than three orders of magnitude greater than that in the Ga-polar region that was explained by the large difference in the adsorption energy for oxygen ({approx}1.3 eV/atom) between the N- and Ga-polar surfaces during the metalorganic chemical vapor deposition.

  18. Excitation mechanisms of Er optical centers in GaN epilayers

    SciTech Connect (OSTI)

    George, D. K.; Hawkins, M. D.; McLaren, M.; Vinh, N. Q.; Jiang, H. X.; Lin, J. Y.; Zavada, J. M.

    2015-10-26

    We report direct evidence of two mechanisms responsible for the excitation of optically active Er{sup 3+} ions in GaN epilayers grown by metal-organic chemical vapor deposition. These mechanisms, resonant excitation via the higher-lying inner 4f shell transitions and band-to-band excitation of the semiconductor host, lead to narrow emission lines from isolated and the defect-related Er optical centers. However, these centers have different photoluminescence spectra, local defect environments, decay dynamics, and excitation cross sections. The photoluminescence at 1.54 μm from the isolated Er optical center which can be excited by either mechanism has the same decay dynamics, but possesses a much higher excitation cross-section under band-to-band excitation. In contrast, the photoluminescence at 1.54 μm from the defect-related Er optical center can only be observed through band-to-band excitation but has the largest excitation cross-section. These results explain the difficulty in achieving gain in Er doped GaN and indicate approaches for realization of optical amplification, and possibly lasing, at room temperature.

  19. Growth modes of InN(000-1) on GaN buffer layers on sapphire

    SciTech Connect (OSTI)

    Liu, Bing; Kitajima, Takeshi; Chen, Dongxue; Leone, Stephen R.

    2005-01-24

    In this work, using atomic force microscopy and scanning tunneling microscopy, we study the surface morphologies of epitaxial InN films grown by plasma-assisted molecular beam epitaxy with intervening GaN buffer layers on sapphire substrates. On smooth GaN buffer layers, nucleation and evolution of three-dimensional InN islands at various coverages and growth temperatures are investigated. The shapes of the InN islands are observed to be predominantly mesa-like with large flat (000-1) tops, which suggests a possible role of indium as a surfactant. Rough GaN buffer layers composed of dense small GaN islands are found to significantly improve uniform InN wetting of the substrates, on which atomically smooth InN films are obtained that show the characteristics of step-flow growth. Scanning tunneling microscopy imaging reveals the defect-mediated surface morphology of smooth InN films, including surface terminations of screw dislocations and a high density of shallow surface pits with depths less than 0.3 nm. The mechanisms of the three-dimensional island size and shape evolution and formation of defects on smooth surfaces are considered.

  20. Impact of defects on the electrical transport, optical properties and failure mechanisms of GaN nanowires.

    SciTech Connect (OSTI)

    Armstrong, Andrew M.; Aubry, Sylvie; Shaner, Eric Arthur; Siegal, Michael P.; Li, Qiming; Jones, Reese E.; Westover, Tyler; Wang, George T.; Zhou, Xiao Wang; Talin, Albert Alec; Bogart, Katherine Huderle Andersen; Harris, C. Thomas; Huang, Jian Yu

    2010-09-01

    We present the results of a three year LDRD project that focused on understanding the impact of defects on the electrical, optical and thermal properties of GaN-based nanowires (NWs). We describe the development and application of a host of experimental techniques to quantify and understand the physics of defects and thermal transport in GaN NWs. We also present the development of analytical models and computational studies of thermal conductivity in GaN NWs. Finally, we present an atomistic model for GaN NW electrical breakdown supported with experimental evidence. GaN-based nanowires are attractive for applications requiring compact, high-current density devices such as ultraviolet laser arrays. Understanding GaN nanowire failure at high-current density is crucial to developing nanowire (NW) devices. Nanowire device failure is likely more complex than thin film due to the prominence of surface effects and enhanced interaction among point defects. Understanding the impact of surfaces and point defects on nanowire thermal and electrical transport is the first step toward rational control and mitigation of device failure mechanisms. However, investigating defects in GaN NWs is extremely challenging because conventional defect spectroscopy techniques are unsuitable for wide-bandgap nanostructures. To understand NW breakdown, the influence of pre-existing and emergent defects during high current stress on NW properties will be investigated. Acute sensitivity of NW thermal conductivity to point-defect density is expected due to the lack of threading dislocation (TD) gettering sites, and enhanced phonon-surface scattering further inhibits thermal transport. Excess defect creation during Joule heating could further degrade thermal conductivity, producing a viscous cycle culminating in catastrophic breakdown. To investigate these issues, a unique combination of electron microscopy, scanning luminescence and photoconductivity implemented at the nanoscale will be used in

  1. Mobile Facility Records Annual Climate Cycle in Niger, Africa

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

    Records Annual Climate Cycle in Niger, Africa Because dust can block incoming solar energy, and because solar energy drives weather and climate, scientists around the world...

  2. Sandia National Laboratories: Facilities

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

    Facilities Bioscience Computing and Information Science Electromagnetics Facilities Electromagnetic Environments Simulator (EMES) Mode Stirred Chamber Lightning Facility Electrostatic Discharge (ESD) Laboratory Other Facilities and Capabilities Programs & Capabilities Partnership Opportunities EM News & Reports Contact Information Engineering Science Geoscience Materials Science Nanodevices and Microsystems Radiation Effects and High Energy Density Science Research Facilities

  3. CMI Unique Facility: Ferromagnetic Materials Characterization Facility |

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

    Critical Materials Institute Ferromagnetic Materials Characterization Facility The Ferromagnetic Materials Characterization Facility is one of more than a dozen unique facilities developed by the Critical Materials Institute, an Energy Innovation Hub of the U.S. Department of Energy. CMI ferromagnetic materials characterization facility at The Ames Laboratory. In the search for substitute materials to replace rare earths in permanent magnets, whenever promising materials are identified,

  4. Uranium Processing Facility | National Nuclear Security Administration

    National Nuclear Security Administration (NNSA)

    Uranium Processing Facility

  5. Effect of ZnO seed layer on the morphology and optical properties of ZnO nanorods grown on GaN buffer layers

    SciTech Connect (OSTI)

    Nandi, R. Mohan, S. Major, S. S.; Srinivasa, R. S.

    2014-04-24

    ZnO nanorods were grown by chemical bath deposition on sputtered, polycrystalline GaN buffer layers with and without ZnO seed layer. Scanning electron microscopy and X-ray diffraction show that the ZnO nanorods on GaN buffer layers are not vertically well aligned. Photoluminescence spectrum of ZnO nanorods grown on GaN buffer layer, however exhibits a much stronger near-band-edge emission and negligible defect emission, compared to the nanorods grown on ZnO buffer layer. These features are attributed to gallium incorporation at the ZnO-GaN interface. The introduction of a thin (25 nm) ZnO seed layer on GaN buffer layer significantly improves the morphology and vertical alignment of ZnO-NRs without sacrificing the high optical quality of ZnO nanorods on GaN buffer layer. The presence of a thick (200 nm) ZnO seed layer completely masks the effect of the underlying GaN buffer layer on the morphology and optical properties of nanorods.

  6. Highly c-axis oriented GaN films grown on free-standing diamond substrates for high-power devices

    SciTech Connect (OSTI)

    Zhang, D. [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China) [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Ministry of Education, Dalian University of Technology, Dalian 116024 (China); Bian, J.M., E-mail: jmbian@dlut.edu.cn [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Qin, F.W.; Wang, J.; Pan, L. [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China) [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Ministry of Education, Dalian University of Technology, Dalian 116024 (China); Zhao, J.M. [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)] [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Zhao, Y.; Bai, Y.Z. [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China) [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Ministry of Education, Dalian University of Technology, Dalian 116024 (China); Du, G.T. [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)] [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2011-10-15

    Highlights: {yields} GaN films are deposited on diamond substrates by ECR-PEMOCVD. {yields} Influence of deposition temperature on the properties of samples is investigated. {yields} Properties of GaN films are dependent on the deposition temperature. -- Abstract: GaN films with highly c-axis preferred orientation are deposited on free-standing thick diamond films by low temperature electron cyclotron resonance plasma enhanced metal organic chemical vapor deposition (ECR-PEMOCVD). The TMGa and N{sub 2} are applied as precursors of Ga and N, respectively. The quality of as-grown GaN films are systematically investigated as a function of deposition temperature by means of X-ray diffraction (XRD) analysis, Hall Effect measurement (HL), room temperature photoluminescence (PL) and atomic force microscopy (AFM). The results show that the dense and uniformed GaN films with highly c-axis preferred orientation are successfully achieved on free-standing diamond substrates under optimized deposition temperature of 400 {sup o}C, and the room temperature PL spectra of the optimized GaN film show a intense ultraviolet near band edge emission and a weak yellow luminescence. The obtained GaN/diamond structure has great potential for the development of high-power semiconductor devices due to its excellent heat dissipation nature.

  7. McKay Bay Facility Biomass Facility | Open Energy Information

    Open Energy Info (EERE)

    Biomass Facility Facility McKay Bay Facility Sector Biomass Facility Type Municipal Solid Waste Location Hillsborough County, Florida Coordinates 27.9903597, -82.3017728...

  8. Facilities | Argonne National Laboratory

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

    Facilities Some of the nation's most powerful and sophisticated facilities for energy research Argonne National Laboratory is home to some of the nation's most powerful and sophisticated research facilities. As a U.S. Department of Energy national laboratory, Argonne offers access to the facilities listed below through a variety of arrangements. Advanced Powertrain Research Facility Center for Transportation Research Materials Engineering Research Facility Distributed Energy Research Center

  9. National User Facilities

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

    National User Facilities Our Vision National User Facilities Research Areas In Focus Global Solutions ⇒ Navigate Section Our Vision National User Facilities Research Areas In Focus Global Solutions Berkeley Lab's User Facilities-Engines of Discovery Berkeley Lab's User Facilities provide state-of-the-art resources for scientists across the nation and around the world. About 10,000 researchers a year use these facilities, representing nearly one third of the total for all Department of Energy

  10. Demonstration of forward inter-band tunneling in GaN by polarization engineering

    SciTech Connect (OSTI)

    Krishnamoorthy, Sriram; Park, Pil Sung; Rajan, Siddharth

    2011-12-05

    We report on the design, fabrication, and characterization of GaN interband tunnel junction showing forward tunneling characteristics. We have achieved very high forward tunneling currents (153 mA/cm{sup 2} at 10 mV, and 17.7 A/cm{sup 2} peak current) in polarization-engineered GaN/InGaN/GaN heterojunction diodes grown by plasma assisted molecular beam epitaxy. We also report the observation of repeatable negative differential resistance in interband III-Nitride tunnel junctions, with peak-valley current ratio of 4 at room temperature. The forward current density achieved in this work meets the typical current drive requirements of a multi-junction solar cell.

  11. Resonant energy transfer between Eu luminescent sites and their local geometry in GaN

    SciTech Connect (OSTI)

    Timmerman, Dolf; Wakamatsu, Ryuta; Tanaka, Kazuteru; Lee, Dong-gun; Koizumi, Atsushi; Fujiwara, Yasufumi

    2015-10-12

    Eu-doped GaN is a solid state material with promising features for quantum manipulation. In this study, we investigate the population dynamics of Eu in ions in this system by resonant excitation. From differences in the emission related to transitions between the {sup 5}D{sub 0} and {sup 7}F{sub 2} manifold in the Eu ions, we can distinguish different luminescence sites and observe that a resonant energy transfer takes place between two of these sites which are in proximity of each other. The time constants related to this energy transfer are on the order of 100 μs. By using different substrates, the energy transfer efficiency could be strongly altered, and it is demonstrated that the coupling between ions has an out-of-plane character. Based on these results, a microscopic model of this combined center is presented.

  12. Influence of the adatom diffusion on selective growth of GaN nanowire regular arrays

    SciTech Connect (OSTI)

    Gotschke, T.; Schumann, T.; Limbach, F.; Calarco, R.; Stoica, T.

    2011-03-07

    Molecular beam epitaxy (MBE) on patterned Si/AlN/Si(111) substrates was used to obtain regular arrays of uniform-size GaN nanowires (NWs). The silicon top layer has been patterned with e-beam lithography, resulting in uniform arrays of holes with different diameters (d{sub h}) and periods (P). While the NW length is almost insensitive to the array parameters, the diameter increases significantly with d{sub h} and P till it saturates at P values higher than 800 nm. A diffusion induced model was used to explain the experimental results with an effective diffusion length of the adatoms on the Si, estimated to be about 400 nm.

  13. Monolithic single GaN nanowire laser with photonic crystal microcavity on silicon

    SciTech Connect (OSTI)

    Heo, Junseok; Guo Wei; Bhattacharya, Pallab

    2011-01-10

    Optically pumped lasing at room temperature in a silicon based monolithic single GaN nanowire with a two-dimensional photonic crystal microcavity is demonstrated. Catalyst-free nanowires with low density ({approx}10{sup 8} cm{sup -2}) are grown on Si by plasma-assisted molecular beam epitaxy. High resolution transmission electron microscopy images reveal that the nanowires are of wurtzite structure and they have no observable defects. A single nanowire laser fabricated on Si is characterized by a lasing transition at {lambda}=371.3 nm with a linewidth of 0.55 nm. The threshold is observed at a pump power density of {approx}120 kW/cm{sup 2} and the spontaneous emission factor {beta} is estimated to be 0.08.

  14. ARM Climate Research Facility

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

    3 ARM Climate Research Facility Quarterly Ingest Status Report A Koontz C Sivaraman ... DOESC-ARM-14-003 ARM Climate Research Facility Quarterly Ingest Report First Quarter: ...

  15. ARM Climate Research Facility

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

    8 ARM Climate Research Facility Quarterly Ingest Status Report A Koontz C Sivaraman ... DOESC-ARM-14-028 ARM Climate Research Facility Quarterly Ingest Report Fourth Quarter: ...

  16. ARM Climate Research Facility

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

    3 ARM Climate Research Facility Quarterly Ingest Status Report A Koontz C Sivaraman ... DOESC-ARM-15-003 ARM Climate Research Facility Quarterly Ingest Report First Quarter: ...

  17. ARM Climate Research Facility

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

    DOESC-ARM-15-019 ARM Climate Research Facility Quarterly Value-Added Product Report ... implemented by the Atmospheric Radiation Measurement (ARM) Climate Research Facility. ...

  18. ARM Climate Research Facility

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

    DOESC-ARM-15-020 ARM Climate Research Facility Quarterly Ingest Report Second Quarter: ... maintained by the Atmospheric Radiation Measurement (ARM) Climate Research Facility. ...

  19. ARM Climate Research Facility

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

    ARM Climate Research Facility Quarterly Ingest Status Report A Koontz C Sivaraman April ... DOESC-ARM-14-014 ARM Climate Research Facility Quarterly Ingest Report Second Quarter: ...

  20. ARM - NSA Barrow Facility

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

    Barrow Facility NSA Related Links Facilities and Instruments Barrow Atqasuk Oliktok Point (AMF3) ES&H Guidance Statement Operations Science Field Campaigns Visiting the Site NSA...

  1. ARM - Facility News Article

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

    30, 2009 Facility News ARM Aerial Facility Leads International Discussions on Aircraft Research Bookmark and Share Five research aircraft participated in the VAMOS...

  2. ARM - Facility News Article

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

    (BERAC) published findings and recommendations from their assessment of the effectiveness of ARM Climate Research Facility as a national scientific user facility. Based on...

  3. NREL: Wind Research - Facilities

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

    support the growth of wind energy development across the United States. National Wind Technology Center Facilities Our facilities are contained within a 305-acre area that...

  4. NREL: Biomass Research - Facilities

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

    Facilities At NREL's state-of-the-art biomass research facilities, researchers design and optimize processes to convert renewable biomass feedstocks into transportation fuels and...

  5. Central Receiver Test Facility

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

    Receiver Test Facility - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us ... Applications National Solar Thermal Test Facility Nuclear Energy Systems ...

  6. ARM - Facility News Article

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

    13, 2014 Facility News Characterizing Ice Nuclei Over Southern Great Plains Bookmark and Share Placed on the upper platform of the SGP Guest Instrument Facility, this filter...

  7. ARM - Facility News Article

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

    facility use by total visitor days and facility to track actual visitors and active user research computer accounts. Historical data show an apparent relationship between the...

  8. ARM - SGP Radiometric Calibration Facility

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

    Radiometric Calibration Facility SGP Related Links Virtual Tour Facilities and Instruments Central Facility Boundary Facility Extended Facility Intermediate Facility Radiometric Calibration Facility Geographic Information ES&H Guidance Statement Operations Science Field Campaigns Visiting the Site Summer Training SGP Fact Sheet Images Information for Guest Scientists Contacts SGP Radiometric Calibration Facility The Radiometric Calibration Facility (RCF) provides shortwave radiometer

  9. Guide to research facilities

    SciTech Connect (OSTI)

    Not Available

    1993-06-01

    This Guide provides information on facilities at US Department of Energy (DOE) and other government laboratories that focus on research and development of energy efficiency and renewable energy technologies. These laboratories have opened these facilities to outside users within the scientific community to encourage cooperation between the laboratories and the private sector. The Guide features two types of facilities: designated user facilities and other research facilities. Designated user facilities are one-of-a-kind DOE facilities that are staffed by personnel with unparalleled expertise and that contain sophisticated equipment. Other research facilities are facilities at DOE and other government laboratories that provide sophisticated equipment, testing areas, or processes that may not be available at private facilities. Each facility listing includes the name and phone number of someone you can call for more information.

  10. Correlation ion mobility spectroscopy

    DOE Patents [OSTI]

    Pfeifer, Kent B.; Rohde, Steven B.

    2008-08-26

    Correlation ion mobility spectrometry (CIMS) uses gating modulation and correlation signal processing to improve IMS instrument performance. Closely spaced ion peaks can be resolved by adding discriminating codes to the gate and matched filtering for the received ion current signal, thereby improving sensitivity and resolution of an ion mobility spectrometer. CIMS can be used to improve the signal-to-noise ratio even for transient chemical samples. CIMS is especially advantageous for small geometry IMS drift tubes that can otherwise have poor resolution due to their small size.

  11. Electron density and currents of AlN/GaN high electron mobility transistors with thin GaN/AlN buffer layer

    SciTech Connect (OSTI)

    Bairamis, A.; Zervos, Ch.; Georgakilas, A.; Adikimenakis, A.; Kostopoulos, A.; Kayambaki, M.; Tsagaraki, K.; Konstantinidis, G.

    2014-09-15

    AlN/GaN high electron mobility transistor (HEMT) structures with thin GaN/AlN buffer layer have been analyzed theoretically and experimentally, and the effects of the AlN barrier and GaN buffer layer thicknesses on two-dimensional electron gas (2DEG) density and transport properties have been evaluated. HEMT structures consisting of [300?nm GaN/ 200?nm AlN] buffer layer on sapphire were grown by plasma-assisted molecular beam epitaxy and exhibited a remarkable agreement with the theoretical calculations, suggesting a negligible influence of the crystalline defects that increase near the heteroepitaxial interface. The 2DEG density varied from 6.8??10{sup 12} to 2.1 10{sup 13} cm{sup ?2} as the AlN barrier thickness increased from 2.2 to 4.5?nm, while a 4.5?nm AlN barrier would result to 3.1??10{sup 13} cm{sup ?2} on a GaN buffer layer. The 3.0?nm AlN barrier structure exhibited the highest 2DEG mobility of 900?cm{sup 2}/Vs for a density of 1.3??10{sup 13} cm{sup ?2}. The results were also confirmed by the performance of 1??m gate-length transistors. The scaling of AlN barrier thickness from 1.5?nm to 4.5?nm could modify the drain-source saturation current, for zero gate-source voltage, from zero (normally off condition) to 0.63?A/mm. The maximum drain-source current was 1.1?A/mm for AlN barrier thickness of 3.0?nm and 3.7?nm, and the maximum extrinsic transconductance was 320 mS/mm for 3.0?nm AlN barrier.

  12. Efficient Switches for Solar Power Conversion: Four Quadrant GaN Switch Enabled Three Phase Grid-Tied Microinverters

    SciTech Connect (OSTI)

    2012-02-13

    Solar ADEPT Project: Transphorm is developing power switches for new types of inverters that improve the efficiency and reliability of converting energy from solar panels into useable electricity for the grid. Transistors act as fast switches and control the electrical energy that flows in an electrical circuit. Turning a transistor off opens the circuit and stops the flow of electrical current; turning it on closes the circuit and allows electrical current to flow. In this way a transistor can be used to convert DC from a solar panel into AC for use in a home. Transphorm’s transistors will enable a single semiconductor device to switch electrical currents at high-voltage in both directions—making the inverter more compact and reliable. Transphorm is using Gallium Nitride (GaN) as a semiconductor material in its transistors instead of silicon, which is used in most conventional transistors, because GaN transistors have lower losses at higher voltages and switching frequencies.

  13. Method of growing GaN films with a low density of structural defects using an interlayer

    DOE Patents [OSTI]

    Bourret-Courchesne, Edith D.

    2003-01-01

    A dramatic reduction of the dislocation density in GaN was obtained by insertion of a single thin interlayer grown at an intermediate temperature (IT-IL) after the growth of an initial grown at high temperature. A description of the growth process is presented with characterization results aimed at understanding the mechanisms of reduction in dislocation density. A large percentage of the threading dislocations present in the first GaN epilayer are found to bend near the interlayer and do not propagate into the top layer which grows at higher temperature in a lateral growth mode. TEM studies show that the mechanisms of dislocation reduction are similar to those described for the epitaxial lateral overgrowth process, however a notable difference is the absence of coalescence boundaries.

  14. Performance and breakdown characteristics of irradiated vertical power GaN P-i-N diodes

    SciTech Connect (OSTI)

    King, M. P.; Armstrong, A. M.; Dickerson, J. R.; Vizkelethy, G.; Fleming, R. M.; Campbell, J.; Wampler, W. R.; Kizilyalli, I. C.; Bour, D. P.; Aktas, O.; Nie, H.; Disney, D.; Wierer, Jr., J.; Allerman, A. A.; Moseley, M. W.; Kaplar, R. J.

    2015-10-29

    Electrical performance and defect characterization of vertical GaN P-i-N diodes before and after irradiation with 2.5 MeV protons and neutrons is investigated. Devices exhibit increase in specific on-resistance following irradiation with protons and neutrons, indicating displacement damage introduces defects into the p-GaN and n- drift regions of the device that impact on-state device performance. The breakdown voltage of these devices, initially above 1700 V, is observed to decrease only slightly for particle fluence <; 1013 cm-2. Furthermore, the unipolar figure of merit for power devices indicates that while the on-resistance and breakdown voltage degrade with irradiation, vertical GaN P-i-Ns remain superior to the performance of the best available, unirradiated silicon devices and on-par with unirradiated modern SiC-based power devices.

  15. ARM - Facility News Article

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

    February 28, 2010 [Facility News] Footprint Adjustments Underway at Southern Great Plains Site Bookmark and Share Upon completion of the SGP footprint reduction, extended facilities 9, 11, 12, 15 and 21 will remain intact, along with the Central Facility (C1) near Lamont. Instrumentation at the remaining sites will be consolidated into the new, smaller footprint. Facilities closed thus far are colored black. Upon completion of the SGP footprint reduction, extended facilities 9, 11, 12, 15 and 21

  16. ARM - Facility News Article

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

    August 15, 2008 [Facility News] New Ceilometer Evaluated at Southern Great Plains Site Bookmark and Share Dan Nelson, SGP facilities manager, inspects the new ceilometer during its evaluation period on the platform of the SGP Guest Instrument Facility between June and July 2008. Dan Nelson, SGP facilities manager, inspects the new ceilometer during its evaluation period on the platform of the SGP Guest Instrument Facility between June and July 2008. To analyze cloud properties, ARM scientists

  17. ARM - Facility News Article

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

    May 15, 2008 [Facility News] National User Facility Organization Meets to Discuss Progress and Ideas Bookmark and Share In late April, the ARM Technical Director attended an annual meeting of the National User Facility Organization. Comprised of representatives from Department of Energy (DOE) national user facilities, the purpose of this group is to promote and encourage discussions among user facility administrators, their management, and their user organization representatives by communicating

  18. ARM - Facility News Article

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

    10, 2016 [Facility News] Opportunity for Cloud Properties Retrieval Algorithm Development: Request for Interest Opened Bookmark and Share The ARM Facility is seeking a scientific consultant to develop an operational cloud property algorithm, using data from ARM facilities and instruments like these scanning cloud radars. The ARM Facility is seeking a scientific consultant to develop an operational cloud property algorithm, using data from ARM facilities and instruments like these scanning cloud

  19. Facilities | Argonne National Laboratory

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

    Facilities Argonne maintains two state-of-the-art facilities for high-energy physics research. The Argonne Wakefield Accelerator Facility is home to technology that produces high accelerating gradients that could form the basis of the next generation of particle accelerators. Additionally, the 4 Tesla Magnet Facility reuses hospital MRI magnets to provide benchmarking for new muon experiments that will be performed at Fermilab. 4 Tesla Magnet Facility Learn More » Argonne Wakefield Accelerator

  20. Electronic and optical device applications of hollow cathode plasma assisted atomic layer deposition based GaN thin films

    SciTech Connect (OSTI)

    Bolat, Sami Tekcan, Burak; Ozgit-Akgun, Cagla; Biyikli, Necmi; Okyay, Ali Kemal

    2015-01-15

    Electronic and optoelectronic devices, namely, thin film transistors (TFTs) and metalsemiconductormetal (MSM) photodetectors, based on GaN films grown by hollow cathode plasma-assisted atomic layer deposition (PA-ALD) are demonstrated. Resistivity of GaN thin films and metal-GaN contact resistance are investigated as a function of annealing temperature. Effect of the plasma gas and postmetallization annealing on the performances of the TFTs as well as the effect of the annealing on the performance of MSM photodetectors are studied. Dark current to voltage and responsivity behavior of MSM devices are investigated as well. TFTs with the N{sub 2}/H{sub 2} PA-ALD based GaN channels are observed to have improved stability and transfer characteristics with respect to NH{sub 3} PA-ALD based transistors. Dark current of the MSM photodetectors is suppressed strongly after high-temperature annealing in N{sub 2}:H{sub 2} ambient.

  1. Transistors for Electric Motor Drives: High-Performance GaN HEMT Modules for Agile Power Electronics

    SciTech Connect (OSTI)

    2010-09-01

    ADEPT Project: Transphorm is developing transistors with gallium nitride (GaN) semiconductors that could be used to make cost-effective, high-performance power converters for a variety of applications, including electric motor drives which transmit power to a motor. A transistor acts like a switch, controlling the electrical energy that flows around an electrical circuit. Most transistors today use low-cost silicon semiconductors to conduct electrical energy, but silicon transistors don’t operate efficiently at high speeds and voltage levels. Transphorm is using GaN as a semiconductor material in its transistors because GaN performs better at higher voltages and frequencies, and it is more energy efficient than straight silicon. However, Transphorm is using inexpensive silicon as a base to help keep costs low. The company is also packaging its transistors with other electrical components that can operate quickly and efficiently at high power levels—increasing the overall efficiency of both the transistor and the entire motor drive.

  2. GaN nanowires with pentagon shape cross-section by ammonia-source molecular beam epitaxy

    SciTech Connect (OSTI)

    Lin, Yong; Leung, Benjamin; Li, Qiming; Figiel, Jeffrey J.; Wang, George T.

    2015-07-14

    In this study, ammonia-based molecular beam epitaxy (NH3-MBE) was used to grow catalyst-assisted GaN nanowires on (11¯02) r-plane sapphire substrates. Dislocation free [112¯0] oriented nanowires are formed with pentagon shape cross-section, instead of the usual triangular shape facet configuration. Specifically, the cross-section is the result of the additional two nonpolar {101¯0} side facets, which appear due to a decrease in relative growth rate of the {101¯0} facets to the {101¯1} and {101¯1} facets under the growth regime in NH3-MBE. Compared to GaN nanowires grown by Ni-catalyzed metal–organic chemical vapor deposition, the NH3-MBE grown GaN nanowires show more than an order of magnitude increase in band-edge to yellow luminescence intensity ratio, as measured by cathodoluminescence, indicating improved microstructural and optical properties.

  3. Elimination of surface band bending on N-polar InN with thin GaN capping

    SciTech Connect (OSTI)

    Kuzmík, J. Haščík, Š.; Kučera, M.; Kúdela, R.; Dobročka, E.; Adikimenakis, A.; Mičušík, M.; Gregor, M.; Plecenik, A.; Georgakilas, A.

    2015-11-09

    0.5–1 μm thick InN (0001) films grown by molecular-beam epitaxy with N- or In-polarity are investigated for the presence of native oxide, surface energy band bending, and effects introduced by 2 to 4 monolayers of GaN capping. Ex situ angle-resolved x-ray photo-electron spectroscopy is used to construct near-surface (GaN)/InN energy profiles, which is combined with deconvolution of In3d signal to trace the presence of InN native oxide for different types of polarity and capping. Downwards surface energy band bending was observed on bare samples with native oxide, regardless of the polarity. It was found that the In-polar InN surface is most readily oxidized, however, with only slightly less band bending if compared with the N-polar sample. On the other hand, InN surface oxidation was effectively mitigated by GaN capping. Still, as confirmed by ultra-violet photo-electron spectroscopy and by energy band diagram calculations, thin GaN cap layer may provide negative piezoelectric polarization charge at the GaN/InN hetero-interface of the N-polar sample, in addition to the passivation effect. These effects raised the band diagram up by about 0.65 eV, reaching a flat-band profile.

  4. GaN nanowires with pentagon shape cross-section by ammonia-source molecular beam epitaxy

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

    Lin, Yong; Leung, Benjamin; Li, Qiming; Figiel, Jeffrey J.; Wang, George T.

    2015-07-14

    In this study, ammonia-based molecular beam epitaxy (NH3-MBE) was used to grow catalyst-assisted GaN nanowires on (11¯02) r-plane sapphire substrates. Dislocation free [112¯0] oriented nanowires are formed with pentagon shape cross-section, instead of the usual triangular shape facet configuration. Specifically, the cross-section is the result of the additional two nonpolar {101¯0} side facets, which appear due to a decrease in relative growth rate of the {101¯0} facets to the {101¯1} and {101¯1} facets under the growth regime in NH3-MBE. Compared to GaN nanowires grown by Ni-catalyzed metal–organic chemical vapor deposition, the NH3-MBE grown GaN nanowires show more than an ordermore » of magnitude increase in band-edge to yellow luminescence intensity ratio, as measured by cathodoluminescence, indicating improved microstructural and optical properties.« less

  5. Benefits of Using Mobile Transformers and Mobile Substations for Rapidly

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

    Restoring Electrical Service: a Report to the United States Congress Pursuant to Section 1816 of the Energy Policy Act of 2005 (August 2006) | Department of Energy Using Mobile Transformers and Mobile Substations for Rapidly Restoring Electrical Service: a Report to the United States Congress Pursuant to Section 1816 of the Energy Policy Act of 2005 (August 2006) Benefits of Using Mobile Transformers and Mobile Substations for Rapidly Restoring Electrical Service: a Report to the United

  6. Mobil lube dewaxing technologies

    SciTech Connect (OSTI)

    Baker, C.L.; McGuiness, M.P.

    1995-09-01

    Currently, the lube refining industry is in a period of transition, with both hydroprocessing and catalytic dewaxing gathering momentum as replacements for solvent extraction and solvent dewaxing. In addition, lube product quality requirements have been increasing, both in the US and abroad. Mobil has developed a broad array of dewaxing catalytic technologies which can serve refiners throughout the stages of this transition. In the future, lube feedstocks which vary in source and wax content will become increasingly important, requiring an optimized system for highest performance. The Mobil Lube Dewaxing (MLDW) process is the work-horse of the catalytic dewaxing technologies, being a robust, low cost technology suitable for both solvent extracted and hydrocracked feeds. The Mobil Selective Dewaxing (MSDW) process has been recently introduced in response to the growth of hydroprocessing. MSDW requires either severely hydrotreated or hydrocracked feeds and provides improved lube yields and VI. For refiners with hydrocrackers and solvent dewaxing units, Mobil Wax Isomerization (MWI) technology can make higher VI base stocks to meet the growing demand for very high quality lube products. A review of these three technologies is presented in this paper.

  7. Mobile lighting apparatus

    DOE Patents [OSTI]

    Roe, George Michael; Klebanoff, Leonard Elliott; Rea, Gerald W; Drake, Robert A; Johnson, Terry A; Wingert, Steven John; Damberger, Thomas A; Skradski, Thomas J; Radley, Christopher James; Oros, James M; Schuttinger, Paul G; Grupp, David J; Prey, Stephen Carl

    2013-05-14

    A mobile lighting apparatus includes a portable frame such as a moveable trailer or skid having a light tower thereon. The light tower is moveable from a stowed position to a deployed position. A hydrogen-powered fuel cell is located on the portable frame to provide electrical power to an array of the energy efficient lights located on the light tower.

  8. Mobility Agreement for Criminal Investigators | Department of...

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

    Mobility Agreement for Criminal Investigators Mobility Agreement for Criminal Investigators PDF icon Mobility Agreement More Documents & Publications Semiannual Report to Congress: ...

  9. Mobility platform coupling device and method for coupling mobility platforms

    DOE Patents [OSTI]

    Shirey, David L.; Hayward, David R.; Buttz, James H.

    2002-01-01

    A coupling device for connecting a first mobility platform to a second mobility platform in tandem. An example mobility platform is a robot. The coupling device has a loose link mode for normal steering conditions and a locking position, tight link mode for navigation across difficult terrain and across obstacles, for traversing chasms, and for navigating with a reduced footprint in tight steering conditions.

  10. Calibration Facilities | Department of Energy

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

    Calibration Facilities Calibration Facilities Calibration Facilities Calibration Facilities Calibration Facilities Calibration Facilities DOE supports the development, standardization, and maintenance of calibration facilities for environmental radiation sensors. Radiation standards at the facilities are primarily used to calibrate portable surface gamma-ray survey meters and borehole logging instruments used for uranium and other mineral exploration and remedial action measurements. Standards