WorldWideScience

Sample records for semiconductors annual subcontract

  1. Annual Report: Photovoltaic Subcontract Program FY 1990

    Energy Technology Data Exchange (ETDEWEB)

    Summers, K. A. [Solar Energy Research Inst., Golden, CO (United States)

    1991-03-01

    This report summarizes the progress of the Photovoltaic (PV) Subcontract Program of the Solar Energy Research Institute (SERI) from October 1, 1989 through September 30, 1990. The PV Subcontract Program is responsible for managing the subcontracted portion of SERI's PV Advanced Research and Development Project. In fiscal year 1990, this included more than 54 subcontracts with a total annualized funding of approximately $11.9 million. Approximately two-thirds of the subcontracts were with universities at a total funding of nearly $3.3 million. The six technical sections of the report cover the main areas of the subcontract program: the Amorphous Silicon Research Project, Polycrystalline Thin Films, Crystalline Silicon Materials Research, High-Efficiency Concepts, the New Ideas Program, and the University Participation Program. Technical summaries of each of the subcontracted programs provide a discussion of approaches, major accomplishments in FY 1990, and future research directions. Another section introduces the PVMaT project and reports on its progress.

  2. Annual Report: Photovoltaic Subcontract Program FY 1991

    Energy Technology Data Exchange (ETDEWEB)

    Summers, K. A. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    1992-03-01

    This report summarizes the fiscal year (FY) 1991 (October 1, 1990, through September 30, 1991) progress of the subcontracted photovoltaic (PV) research and development (R&D) performed under the Photovoltaic Advanced Research and Development Project at the National Renewable Energy Laboratory (NREL)-formerly the Solar Energy Research Institute (SERI). The mission of the national PV program is to develop PV technology for large-scale generation of economically competitive electric power in the United States. The technical sections of the report cover the main areas of the subcontract program: the Amorphous Silicon Research Project, Polycrystalline Thin Films, Crystalline Silicon Materials Research, High Efficiency Concepts, the New Ideas Program, the University Participation Program, and the Photovoltaic Manufacturing Technology (PVMaT) project. Technical summaries of each of the subcontracted programs provide a discussion of approaches, major accomplishments in FY 1991, and future research directions.

  3. Photovoltaic Subcontract Program. Annual report, FY 1992

    Energy Technology Data Exchange (ETDEWEB)

    1993-03-01

    This report summarizes the fiscal year (FY) 1992 progress of the subcontracted photovoltaic (PV) research and development (R&D) performed under the Photovoltaic Advanced Research and Development Project at the National Renewable Energy Laboratory (NREL)-formerly the Solar Energy Research Institute (SERI). The mission of the national PV program is to develop PV technology for large-scale generation of economically competitive electric power in the United States. The technical sections of the report cover the main areas of the subcontract program: the Crystalline Materials and Advanced Concepts project, the Polycrystalline Thin Films project, Amorphous Silicon Research project, the Photovoltaic Manufacturing Technology (PVMaT) project, PV Module and System Performance and Engineering project, and the PV Analysis and Applications Development project. Technical summaries of each of the subcontracted programs provide a discussion of approaches, major accomplishments in FY 1992, and future research directions.

  4. Photovoltaic Subcontract Program, FY 1991. Annual report, [October 1, 1990--September 30, 1991

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-01

    This report summarizes the fiscal year (FY) 1991 (October 1, 1990, through September 30, 1991) progress of the subcontracted photovoltaic (PV) research and development (R&D) performed under the Photovoltaic Advanced Research and Development Project at the National Renewable Energy Laboratory (NREL) -- formerly the Solar Energy Research Institute (SERI). The mission of the national PV program is to develop PV technology for large-scale generation of economically competitive electric power in the United States. The technical sections of the report cover the main areas of the subcontract program: the Amorphous Silicon Research Project, Polycrystalline Thin Films, Crystalline Silicon Materials Research, High-Efficiency Concepts, the New Ideas Program, the University Participation Program, and the Photovoltaic Manufacturing Technology (PVMaT) project. Technical summaries of each of the subcontracted programs provide a discussion of approaches, major accomplishments in FY 1991, and future research directions.

  5. Photovoltaic Subcontract Program, FY 1990

    Energy Technology Data Exchange (ETDEWEB)

    Summers, K.A. (ed.)

    1991-03-01

    This report summarizes the progress of the subcontracted photovoltaic (PV) research and development (R D) performed under the Photovoltaics Program at the Solar Energy Research Institute (SERI). The SERI subcontracted PV research and development represents most of the subcontracted R D that is funded by the US Department of Energy (DOE) National Photovoltaics Program. This report covers fiscal year (FY) 1990: October 1, 1989 through September 30, 1990. During FY 1990, the SERI PV program started to implement a new DOE subcontract initiative, entitled the Photovoltaic Manufacturing Technology (PVMaT) Project.'' Excluding (PVMaT) because it was in a start-up phase, in FY 1990 there were 54 subcontracts with a total annualized funding of approximately $11.9 million. Approximately two-thirds of those subcontracts were with universities, at a total funding of over $3.3 million. Cost sharing by industry added another $4.3 million to that $11.9 million of SERI PV subcontracted R D. The six technical sections of this report cover the previously ongoing areas of the subcontracted program: the Amorphous Silicon Research Project, Polycrystalline Thin Films, Crystalline Silicon Materials Research, High-Efficiency Concepts, the New Ideas Program, and the University Participation Program. Technical summaries of each of the subcontracted programs discuss approaches, major accomplishments in FY 1990, and future research directions. Another section introduces the PVMaT project and reports the progress since its inception in FY 1990. Highlights of technology transfer activities are also reported.

  6. Market-Driven EFG Modules, Annual Subcontract Report, 14 December 1996 - 13 February 1998

    Energy Technology Data Exchange (ETDEWEB)

    Kardauskas, M.; Kalejs, J. (ASE Americas, Inc., Billerica, Massachusetts)

    1998-12-15

    This report summarizes the progress made at ASE Americas Inc. during Phase II of this subcontract. Accomplishments under Task 4: Wafers include optimization of edge-defined film-fed growth (EFG) crystal growth variables, leading to reduced crystal stresses and improved wafer flatness; increased die run length due to improvements in the design of furnace components; construction and testing of EFG growth furnace enclosure; reduction of EFG wafer thickness from 300 {micro}m for 50% of all standard production material; implementation of new equipment to reduce costs of silicon feedstock sorting prior to EFG crystal growth with a 3% increase in silicon feedstock utilization; and development work demonstrating the laser cutting of EFG wafers at higher speeds and with reduced silicon damage. Accomplishments under Task 5: Cells include characterization of cells after diffusion as preliminary work toward improving diffusion conditions and improving cell efficiency; demonstration of a continuous process to remove phosphorus glass from diffused wafers, reducing chemical consumption and hazardous waste by 98%; development of statistical process control methods to improve cell production process control; the use of design of experiments to study interactions between processing at various steps in cell manufacturing, and to develop strategies for productivity improvements; improvements in EFG cell efficiency due to the reduction in average wafer thickness; design and construction of equipment for producing cells with an improved grid design; and demonstration of average efficiencies over 14.1% on production lots of EFG cells. Accomplishments under Task 6: Modules include production and successful testing of prototypes of a lower-cost module diode housing; successful demonstration of a module design that greatly improves collection of light from space between cells in modules; testing of new encapsulants and lamination processes to demonstrate reduced lamination time, improved

  7. Defects and diffusion in semiconductors XIII an annual retrospective

    CERN Document Server

    Fisher, D J

    2011-01-01

    This thirteenth volume in the series covering the latest results in the field includes abstracts of papers which have appeared since the publication of Annual Retrospective XII (Volumes 303-304). As well as the over 300 semiconductor-related abstracts, the issue includes the original papers: ""Effect of KCl Addition upon the Photocatalytic Activity of Zinc Sulphide"" (D.Vaya, A.Jain, S.Lodha, V.K.Sharma, S.C.Ameta), ""Localized Vibrational Mode in Manganese-Doped Zinc Sulphide and Cadmium Sulphide Nanoparticles"" (M.Ragam, N.Sankar, K.Ramachandran), ""The Effect of a Light Impurity on the Elec

  8. Large-area triple-junction a-Si alloy production scaleup. Annual subcontract report, 17 March 1993--18 March 1994

    Energy Technology Data Exchange (ETDEWEB)

    Oswald, R.; Morris, J. [Solarex Corp., Newtown, PA (United States). Thin Film Div.

    1994-11-01

    The objective of this subcontract over its three-year duration is to advance Solarex`s photovoltaic manufacturing technologies, reduce its a-Si:H module production costs, increase module performance and expand the Solarex commercial production capacity. Solarex shall meet these objectives by improving the deposition and quality of the transparent front contact, by optimizing the laser patterning process, scaling-up the semiconductor deposition process, improving the back contact deposition, scaling-up and improving the encapsulation and testing of its a-Si:H modules. In the Phase 2 portion of this subcontract, Solarex focused on improving deposition of the front contact, investigating alternate feed stocks for the front contact, maximizing throughput and area utilization for all laser scribes, optimizing a-Si:H deposition equipment to achieve uniform deposition over large-areas, optimizing the triple-junction module fabrication process, evaluating the materials to deposit the rear contact, and optimizing the combination of isolation scribe and encapsulant to pass the wet high potential test. Progress is reported on the following: Front contact development; Laser scribe process development; Amorphous silicon based semiconductor deposition; Rear contact deposition process; Frit/bus/wire/frame; Materials handling; and Environmental test, yield and performance analysis.

  9. Research Leading to High Throughput Manufacturing of Thin-Film CdTe PV Modules: Annual Subcontract Report, September 2004--September 2005

    Energy Technology Data Exchange (ETDEWEB)

    Powell, R. C.

    2006-04-01

    Specific overall objectives of this subcontract are improvement in baseline field performance of manufactured CdTe PV modules while reducing environmental, health and safety risk in the manufacturing environment. Project objectives focus on four broad categories: (1) development of advanced front-contact window layers, (2) improved semiconductor film deposition, (3) development of improved accelerated life test procedures that indicate baseline field performance, and (4) reduction of cadmium-related environmental, health and safety risks. First Solar has significantly increased manufacturing capacity from less than 2 MW/yr to more than 20 MW/yr, while increasing the average module total-area power conversion efficiency from 7% to >9%. First Solar currently manufactures and sells 50-65-W thin-film CdTe PV modules at a rate of about 1.9 MW/month. Sales backlog (booked sales less current inventory divided by production rate) is more than a year. First Solar is currently building new facilities and installing additional equipment to increase production capacity by 50 MW/yr; the additional capacity is expected to come on line in the third quarter of 2006.

  10. PVMaT improvements in the Solarex photovoltaic module manufacturing technology: Annual subcontract report: May 5, 1998 -- April 30, 1999

    Energy Technology Data Exchange (ETDEWEB)

    Wohlgemuth, J.

    2000-01-10

    This report describes work done by Solarex during the first year of this subcontract. The objective of this three-year PVMaT program is to continue the advancement of Solarex PV manufacturing technologies to design and implement a process that produces polycrystalline silicon PV modules that can be sold profitably for $2.00 per peak watt or less and that will increase the production capacity of the Frederick plant to at least 25 megawatts per year. Accomplishments during the first year of the program include: (1) Verification of the process to produce SiF{sub 4}, the precursor to silicon feedstock. (2) Design of a silicon feedstock pilot facility using the SiNaF process. (3) Development of and transfer to manufacturing of a process to use thinner wire in the wire saw. (4) Completion of a production trial with recycled SiC. (5) Laboratory development of a selective emitter process using rapid thermal processing. (6) Fabrication of high-efficiency polycrystalline cells using silicon nitride from three different sources. (7) Development of a new encapsulation formulation and laboratory demonstration of a 6-minute lamination cycle. (8) Implementation of an automated laminator. (9) Laboratory demonstration of automated handling of ceramics.

  11. Processing and modeling issues for thin-film solar cell devices: Annual subcontract report, January 16, 1995 -- January 15, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Birkmire, R W; Phillips, J E; Buchanan, W A; Eser, E; Hegedus, S S; McCandless, B E; Meyers, P V; Shafarman, W N [Univ. of Delaware, Newark, DE (United States)

    1996-08-01

    The overall mission of the Institute of Energy Conversion is the development of thin film photovoltaic cells, modules, and related manufacturing technology and the education of students and professionals in photovoltaic technology. The objectives of this four-year NREL subcontract are to advance the state of the art and the acceptance of thin film PV modules in the areas of improved technology for thin film deposition, device fabrication, and material and device characterization and modeling, relating to solar cells based on CuInSe{sub 2} and its alloys, on a-Si and its alloys, and on CdTe. In the area of CuInSe{sub 2} and its alloys, EEC researchers have produced CuIn{sub 1-x}GaxSe{sub 2} films by selenization of elemental and alloyed films with H{sub 2}Se and Se vapor and by a wide variety of process variations employing co-evaporation of the elements. Careful design, execution and analysis of these experiments has led to an improved understanding of the reaction chemistry involved, including estimations of the reaction rate constants. Investigation of device fabrication has also included studies of the processing of the Mo, US and ZnO deposition parameters and their influence on device properties. An indication of the success of these procedures was the fabrication of a 15% efficiency CuIn{sub 1-x}GaxSe{sub 2} solar cell.

  12. Processing and modeling issues for thin-film solar cell devices. Annual subcontract report, January 16, 1994--January 15, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Birkmire, R.W.; Phillips, J.E.; Buchanan, W.A.; Hegedus, S.S.; McCandless, B.E.; Shafarman, W.N. [Delaware Univ., Newark, DE (United States). Inst. of Energy Conversion

    1995-06-01

    This report describes results achieved during the second phase of a four year subcontract to develop and understand thin film solar cell technology related to a-Si and its alloys, CuIn{sub 1{minus}x}Ga{sub x}Se{sub 2}, and CdTe. Accomplishments during this phase include, development of equations and reaction rates for the formation of CuIn{sub 1{minus}x}Ga{sub x}Se{sub 2} films by selenization, fabrication of a 15% efficient CuIn{sub 1{minus}x}Ga{sub x}Se{sub 2} cell, development of a reproducible, reliable Cu-diffused contact to CdTe, investigation of the role of CdTe-CdS interdiffusion on device operation, investigation of the substitution of HCl for CdCl{sub 2} in the post-deposition heat treatment of CdTe/CdS, demonstration of an improved reactor design for deposition of a-Si films, demonstration of improved process control in the fabrication of a ten set series of runs producing {approximately}8% efficient a-Si devices, demonstration of the utility of a simplified optical model for determining quantity and effect of current generation in each layer of a triple stacked a-Si cell, presentation of analytical and modeling procedures adapted to devices produced with each material system, presentation of baseline parameters for devices produced with each material system, and various investigations of the roles played by other layers in thin film devices including the Mo underlayer, CdS and ZnO in CuIn{sub 1{minus}x}Ga{sub x}Se{sub 2} devices, the CdS in CdTe devices, and the ZnO as window layer and as part of the back surface reflector in a-Si devices. In addition, collaborations with over ten research groups are briefly described. 73 refs., 54 figs., 34 tabs.

  13. Subcontracting Management Handbook

    Science.gov (United States)

    1988-05-01

    Subcontractor Pr , rosals _8-8 9.0 CRITICAL SUBCONTRACTING ASPECTS 9- I 9 I Source Selection 9-1 9 2 Flowdown of Specifications, Standards Terms and...Subcontracting Management Course Material, Subcontracting Management Course, AFSC Systems Acquisition School, Brooks AFB, San Antonio , TX. "The Role

  14. Production Subcontracting and Location

    OpenAIRE

    Holl, Adelheid

    2007-01-01

    Using data from a panel of Spanish manufacturing firms, I examine factors that explain firms’ production subcontracting decisions and test whether there is any evidence that production subcontracting is facilitated in areas typically associated with higher agglomeration economies. The results show that location matters. Firms in industry agglomerations are more likely to subcontract production activities. While in general, larger and older firms as well as high wage firms show a greater proba...

  15. Non-H{sub 2}Se, ultra-thin CIS devices. Annual subcontract report, 10 March 1992--9 November 1992

    Energy Technology Data Exchange (ETDEWEB)

    Delahoy, A.E.; Britt, J.; Kiss, Z. [Energy Photovoltaics, Inc., Princeton, NJ (United States)

    1993-02-01

    This report describes work done during Phase I of a 3-phase, cost- shared contract. Objective of the subcontract is to demonstrate 12% total-area efficiency copper indium diselenide (CIS) solar cells and 50-W CIS modules average at least 8 W/ft{sup 2} in the third year. At the end of Phase I, EPV delivered to NREL a 1.1 cm{sup 2} CIS cell with an active area efficiency of 10.5%. the corresponding total-area efficiency is 7.9%.

  16. Twenty years of semiconductor surface and interface structure determination and prediction: The role of the annual conferences on the physics and chemistry of semiconductor interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Duke, C.B. [Xerox Webster Research Center, NY (United States)

    1993-07-01

    During the two decades 1974-93, semiconductor surface structure determination has evolved into a routine tool. This rapid evolution resulted from the confluence of three factors: the development of new techniques (e.g., scanning tunneling microscopy) and the improvement of old ones (e.g., low-energy electron diffraction), greatly increased reliability of vacuum equipment and electronics, and orders of magnitude enhancement in the speed and cost effectiveness of digital computers. A critical role of the annual conferences on the physics and chemistry of semiconductor interfaces (PCSI) in this evolution was to focus the attention of researchers on surface and interface structure as the key measurable intermediary between electronic materials processing and the performance of the resulting devices. Studies of several important systems, e.g., the (110) cleavage faces and (100) molecular-beam epitaxy growth faces of zinc blende structure compound semiconductors, were driven by events reported at PCSI conferences. These conferences were instrumental in stimulating the development of theoretical models which could extrapolate between vacuum surfaces, for which structural data have become readily available, and semiconductor heterostructures, for which comparable data are only now beginning to appear. Because of this development, the insight developed for vacuum surfaces is currently being applied to the prediction of interface specific electronic properties of semiconductor heterostructures (e.g., band offsets in heterojunctions and Schottky barrier heights in epitaxical metal-semiconductor junctions). In this way the PCSI conferences have forged a link between the surface science of semiconductors and the fabrication of microelectronic devices so that both evolve faster than either one would have otherwise. This article documents some specific examples of the nature and consequences of this process. 164 refs., 9 figs.

  17. Photovoltaic Subcontract Program

    Energy Technology Data Exchange (ETDEWEB)

    Surek, Thomas; Catalano, Anthony

    1993-03-01

    This report summarizes the fiscal year (FY) 1992 progress of the subcontracted photovoltaic (PV) research and development (R D) performed under the Photovoltaic Advanced Research and Development Project at the National Renewable Energy Laboratory (NREL)-formerly the Solar Energy Research Institute (SERI). The mission of the national PV program is to develop PV technology for large-scale generation of economically competitive electric power in the United States. The technical sections of the report cover the main areas of the subcontract program: the Crystalline Materials and Advanced Concepts project, the Polycrystalline Thin Films project, Amorphous Silicon Research project, the Photovoltaic Manufacturing Technology (PVMaT) project, PV Module and System Performance and Engineering project, and the PV Analysis and Applications Development project. Technical summaries of each of the subcontracted programs provide a discussion of approaches, major accomplishments in FY 1992, and future research directions.

  18. Subcontracting Railway Maintenance

    OpenAIRE

    Thommesen, Jacob

    2010-01-01

    In several European countries, national railway operators have been dismantled and partly privatized to create new contractual relations where operations originally performed internally are now outsourced to several companies. Breaking up work across several independent organizational and commercial entities tends to make coordination and control tasks more complex. It is therefore of interest to explore whether increased and specific risks arise when subcontracting arrangements of safety cri...

  19. Development of an In-Line Minority-Carrier Lifetime Monitoring Tool for Process Control during Fabrication of Crystalline Silicon Solar Cells: Annual Subcontract Report, June 2003 (Revised)

    Energy Technology Data Exchange (ETDEWEB)

    Sinton, R. A.

    2004-04-01

    Under the PV Manufacturing R&D subcontract''Development of an In-Line, Minority-Carrier Lifetime Monitoring Tool for Process Control during Fabrication of Crystalline Silicon Solar Cells'', Sinton Consulting developed prototypes for several new instruments for use in the manufacture of silicon solar cells. These instruments are based on two families of R&D instruments that were previously available, an illumination vs. open-circuit-voltage technique and the quasi-steady state RF photoconductance technique for measuring minority-carrier lifetime. Compared to the previous instruments, the new prototypes are about 20 times faster per measurement, and have automated data analysis that does not require user intervention even when confronted by challenging cases. For example, un-passivated multi-crystalline wafers with large variations in lifetime and trapping behavior can be measured sequentially without error. Five instruments have been prototyped in this project to date, including a block tester for evaluating cast or HEM silicon blocks, a CZ ingot tester, an FZ boule tester for use with long-lifetime silicon, and an in-line sample head for measuring wafers. The CZ ingot tester and the FZ boule tester are already being used within industry and there is interest in the other prototypes. For each instrument, substantial R&D work was required in developing the device physics and analysis as well as for the hardware. This work has been documented in a series of application notes and conference publications, and will result in significant improvements for both the R&D and the industrial types of instruments.

  20. Photovoltaic Manufacturing Cost and Throughput Improvements for Thin-Film CIGS-Based Modules; Phase II Annual Subcontract Technical Report, July 1999 - August 2000

    Energy Technology Data Exchange (ETDEWEB)

    Wendt, T.G.; Wiedeman, S. (Global Solar Energy, L.L.C.)

    2001-03-12

    Thin-film photovoltaics (PV) has expanded dramatically in the last five years, but commercial use remains limited by performance, cost, and reliability. Of all the thin-film systems, copper indium gallium diselenide (CIGS) has demonstrated the greatest potential for achieving high performance at a low cost. The highest-quality CIGS has been formed by multi-source co-evaporation, a technique pioneered in this country by researchers at NREL. Multi-source co-evaporation is also potentially the fastest and most cost-effective method of CIGS absorber deposition. Global Solar Energy (GSE) has adapted multi-source co-evaporation of CIGS to large-area, roll-to-roll processing on flexible substrates, enabling several manufacturing and product capability advantages. Roll-to-roll processing enables a low-cost, automated continuous manufacturing process. Flexible substrates enable product application in unique, as well as traditional, areas. The primary objectives of the GSE Photovoltaic Manufacturing Technology (PVMaT) subcontract are to reduce cost and expand the production rate of thin-film CIGS-based PV modules on flexible substrates. Improvements will be implemented in monolithic integration, CIGS deposition, contact deposition, and in-situ CIGS control and monitoring. Specific goals of the three-year contract are: - Monolithic Integration - Increase integration speed by developing high-speed, all-laser scribing processes that are more than 100% faster than the baseline process and offer clean, selective scribing; increase capacity and substantially reduce module area losses by insulating materials with high accuracy into laser scribes. - Absorber Deposition - Increase absorber-layer deposition rate by 75% in the large-area, continuous GSE process, increasing throughput and reducing labor and capital costs. Integrate a parallel detector spectroscopic ellipsometer (PDSE) with mathematical algorithms for in-situ control of the CIGS absorber, enabling runs of over 300 meters

  1. 13 CFR 125.3 - Subcontracting assistance.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Subcontracting assistance. 125.3... § 125.3 Subcontracting assistance. (a) General. The purpose of the subcontracting assistance program is to provide the maximum practicable subcontracting opportunities for small business concerns...

  2. 48 CFR 252.237-7006 - Subcontracting.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Subcontracting. 252.237... Clauses 252.237-7006 Subcontracting. As prescribed in 237.7003(b), use the following clause: Subcontracting (DEC 1991) The Contractor shall not subcontract any work under this contract without the...

  3. 48 CFR 252.247-7018 - Subcontracting.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Subcontracting. 252.247... Clauses 252.247-7018 Subcontracting. As prescribed in 247.270-3(m), use the following clause: Subcontracting (DEC 1991) The Contractor shall not subcontract without the prior written approval of the...

  4. 78 FR 42391 - Small Business Subcontracting

    Science.gov (United States)

    2013-07-16

    ... subcontractor used in preparing its bid or proposal during contract performance. This rule also adds a provision... clarifies which subcontracts must be included in subcontracting data reporting, which subcontracts should be excluded, and the way subcontracting data is reported. The rule also makes changes to update its...

  5. 76 FR 74749 - Small Business Subcontracting

    Science.gov (United States)

    2011-12-01

    ... whenever the prime contractor does not utilize a subcontractor used in preparing its bid or proposal during... performance. SBA also proposed to clarify which subcontracts must be included in subcontracting data reporting, which subcontracts should be excluded, and the way subcontracting data is reported. SBA also proposed to...

  6. 76 FR 61626 - Small Business Subcontracting

    Science.gov (United States)

    2011-10-05

    ... used in preparing its bid or proposal during contract performance. SBA is also proposing to amend its... which subcontracts must be included in subcontracting data reporting, which subcontracts should be excluded, and the way subcontracting data is reported. SBA is also proposing to make other changes to...

  7. New III-V cell design approaches for very high efficiency. Annual subcontract report, 1 August 1991--31 July 1992

    Energy Technology Data Exchange (ETDEWEB)

    Lundstrom, M.S.; Melloch, M.R.; Lush, G.B.; Patkar, M.P.; Young, M.P. [Purdue Univ., Lafayette, IN (United States)

    1993-04-01

    This report describes to examine new solar cell desip approaches for achieving very high conversion efficiencies. The program consists of two elements. The first centers on exploring new thin-film approaches specifically designed for M-III semiconductors. Substantial efficiency gains may be possible by employing light trapping techniques to confine the incident photons, as well as the photons emitted by radiative recombination. The thin-film approach is a promising route for achieving substantial performance improvements in the already high-efficiency, single-junction, III-V cell. The second element of the research involves exploring desip approaches for achieving high conversion efficiencies without requiring extremely high-quality material. This work has applications to multiple-junction cells, for which the selection of a component cell often involves a compromise between optimum band pp and optimum material quality. It could also be a benefit manufacturing environment by making the cell`s efficiency less dependent on materialquality.

  8. New III-V cell design approaches for very high efficiency. Annual subcontract report, 1 August 1990--31 July 1991

    Energy Technology Data Exchange (ETDEWEB)

    Lundstrom, M.S.; Melloch, M.R.; Lush, G.B.; O`Bradovich, G.J.; Young, M.P. [Purdue Univ., Lafayette, IN (United States)

    1993-01-01

    This report describes progress during the first year of a three-year project. The objective of the research is to examine new design approaches for achieving very high conversion efficiencies. The program is divided into two areas. The first centers on exploring new thin-film approaches specifically designed for III-V semiconductors. The second area centers on exploring design approaches for achieving high conversion efficiencies without requiring extremely high quality material. Research activities consisted of an experimental study of minority carrier recombination in n-type, metal-organic chemical vapor deposition (MOCVD)-deposited GaAs, an assessment of the minority carrier lifetimes in n-GaAs grown by molecular beam epitaxy, and developing a high-efficiency cell fabrication process.

  9. Subcontracting Railway Maintenance

    DEFF Research Database (Denmark)

    Thommesen, Jacob

    2010-01-01

    In several European countries, national railway operators have been dismantled and partly privatized to create new contractual relations where operations originally performed internally are now outsourced to several companies. Breaking up work across several independent organizational and commerc...... funded via internal sources and the OECD Halden Project, is inspired by efforts of a task on “safety challenges posed by outsourcing” of EU iNTeg-Risk project (FP7 CP-IP 213345-2)...... and commercial entities tends to make coordination and control tasks more complex. It is therefore of interest to explore whether increased and specific risks arise when subcontracting arrangements of safety critical work safety are implemented. This paper focuses on the safety challenges faced by a Danish......In several European countries, national railway operators have been dismantled and partly privatized to create new contractual relations where operations originally performed internally are now outsourced to several companies. Breaking up work across several independent organizational...

  10. Specific PVMaT R and D in CdTe Product Manufacturing; Phase II Annual Subcontract Technical Report; May 1999--September 2000

    Energy Technology Data Exchange (ETDEWEB)

    McMaster, A. (First Solar, LLC)

    2001-01-22

    Just prior to the beginning of Phase II of the PVMaT project Solar Cells, Inc, (SCI) and True North Partners of Scottsdale, AZ, formed a joint venture partnership name First Solar, LLC. By the end of 1999, this event resulted in the construction of a new major manufacturing plant for photovoltaic modules, based on cadmium telluride, located in Perrysburg, a suburb of Toledo, Ohio. This plant was designed to be capable of producing PV modules at a rate of 100 MW per year within about three years. Significantly, a new semiconductor coating system, the heat of the production line, has already shown the capability of the 100 MW per year rate. These events have led to the expansion of the effort on the PVMaT project that included the former SCI team in Toledo, Ohio, a new team of engineering subcontractor, Product Search, Inc., and, later, a new laser team from First Solar, both from Scottsdale, Arizona. These three teams joined in a collaborative effort on Tasks 4: Manufacturing Line Improvements, on Task 5: Product Readiness, and on Task Environmental, Health, and Safety Issues. One Task 4 goal was to address the technical issues of the failed UL 1703 qualification testing in Phase I. Completing this goal, along with module lamination improvement done in Task 5, was instrumental in the design, fabrication, and installation of a high-throughput solar finishing line. The main components of this line, also a Task 4 project, were successfully tested in module finalization on the production line. Developing a novel, single-laser scribing system was another major accomplishment. In Task 5, the major activity was improved module lamination. Progress in Tasks 4 and 5 resulted in improved modules that were submitted for UL 1703 qualification testing. In March 2000, a new encapsulation process came under development, in which the back glass cover plate is substituted by a combination of a polymer layer as a dielectric and aluminum foil as a moisture barrier. The go al of the

  11. FY06 Annual Report: Amorphous Semiconductors for Gamma Radiation Detection (ASGRAD)

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Bradley R.; Riley, Brian J.; Crum, Jarrod V.; Sundaram, S. K.; Henager, Charles H.; Zhang, Yanwen; Shutthanandan, V.

    2007-01-01

    We describe progress in the development of new materials for portable, room-temperature, gamma-radiation detection at Pacific Northwest National Laboratory at the Hanford Site in Washington State. High Z, high resistivity, amorphous semiconductors are being designed for use as solid-state detectors at near ambient temperatures; principles of operation are analogous to single-crystal semiconducting detectors. Amorphous semiconductors have both advantages and disadvantages compared to single crystals, and this project is developing methods to mitigate technical problems and design optimized material for gamma detection. Several issues involved in the fabrication of amorphous semiconductors are described, including reaction thermodynamics and kinetics, the development of pyrolytic coating, and the synthesis of ingots. The characterization of amorphous semiconductors is described, including sectioning and polishing protocols, optical microscopy, X-ray diffraction, scanning electron microscopy, optical spectroscopy, particle-induced X-ram emission, Rutherford backscattering, and electrical testing. Then collaboration with the University of Illinois at Urbana-Champaign is discussed in the areas of Hall-effect measurements and current voltage data. Finally, we discuss the strategy for continuing the program.

  12. SETEC/Semiconductor Manufacturing Technologies Program: 1999 Annual and Final Report

    Energy Technology Data Exchange (ETDEWEB)

    MCBRAYER,JOHN D.

    2000-12-01

    This report summarizes the results of work conducted by the Semiconductor Manufacturing Technologies Program at Sandia National Laboratories (Sandia) during 1999. This work was performed by one working group: the Semiconductor Equipment Technology Center (SETEC). The group's projects included Numerical/Experimental Characterization of the Growth of Single-Crystal Calcium Fluoride (CaF{sub 2}); The Use of High-Resolution Transmission Electron Microscopy (HRTEM) Imaging for Certifying Critical-Dimension Reference Materials Fabricated with Silicon Micromachining; Assembly Test Chip for Flip Chip on Board; Plasma Mechanism Validation: Modeling and Experimentation; and Model-Based Reduction of Contamination in Gate-Quality Nitride Reactor. During 1999, all projects focused on meeting customer needs in a timely manner and ensuring that projects were aligned with the goals of the National Technology Roadmap for Semiconductors sponsored by the Semiconductor Industry Association and with Sandia's defense mission. This report also provides a short history of the Sandia/SEMATECH relationship and a brief on all projects completed during the seven years of the program.

  13. Polycrystalline CuInSe{sub 2} and CdTe PV solar cells. Annual subcontract report, 15 April 1993--14 April 1994

    Energy Technology Data Exchange (ETDEWEB)

    Dhere, N.G. [Florida Solar Energy Center, Cape Canaveral, FL (United States)

    1994-11-01

    This is an annual technical report on the Phase 2 of a three-year phased research program. The principal objective of the research project is to develop novel and low-cost processes for the fabrication of stable and efficient CuIn{sub 1{minus}x}Ga{sub x}Se{sub 2} and CdTe polycrystalline-thin-film solar cells using reliable techniques amenable to scale-up for economic, large-scale manufacture. The aims are to develop a process for the non-toxic selenization so as to avoid the use of extremely toxic H{sub 2}Se in the fabrication of CuIn{sub 1{minus}x}Ga{sub x}Se{sub 2} thin-film solar cells; to optimize selenization parameters; to develop a process for the fabrication of CdTe solar cells using Cd and Te layers sputtered from elemental targets; to develop an integrated process for promoting the interdiffusion between Cd/Te layers, CdTe phase formation, grain growth, type conversion, and junction formation; to improve adhesion; to minimize residual stresses; to improve the metallic back-contact; to improve the uniformity, stoichiometry, and morphology of CuIn{sub 1{minus}x}Ga{sub x}Se{sub 2} and CdTe thin films; and to improve the efficiency of CuIn{sub 1{minus}x}Ga{sub x}Se{sub 2} and CdTe solar cells.

  14. Large-Scale PV Module Manufacturing Using Ultra-Thin Polycrystalline Silicon Solar Cells: Annual Subcontract Report, 1 April 2002--30 September 2003 (Revised)

    Energy Technology Data Exchange (ETDEWEB)

    Wohlgemuth, J.; Shea, S. P.

    2004-04-01

    The goal of BP Solar's Crystalline PVMaT program is to improve the present polycrystalline silicon manufacturing facility to reduce cost, improve efficiency, and increase production capacity. Key components of the program are: increasing ingot size; improving ingot material quality; improving material handling; developing wire saws to slice 100 ..mu..m thick silicon wafers on 200 ..mu..m centers; developing equipment for demounting and subsequent handling of very thin silicon wafers; developing cell processes using 100 ..mu..m thick silicon wafers that produce encapsulated cells with efficiencies of at least 15.4% at an overall yield exceeding 95%; expanding existing in-line manufacturing data reporting systems to provide active process control; establishing a 50 MW (annual nominal capacity) green-field Mega plant factory model template based on this new thin polycrystalline silicon technology; and facilitating an increase in the silicon feedstock industry's production capacity for lower-cost solar-grade silicon feedstock.

  15. Large-Scale PV Module Manufacturing Using Ultra-Thin Polycrystalline Silicon Solar Cells: Annual Subcontract Report, 1 October 2003--30 September 2004

    Energy Technology Data Exchange (ETDEWEB)

    Wohlgemuth, J.; Narayanan, M.

    2005-03-01

    The major objectives of this program are to continue the advancement of BP Solar polycrystalline silicon manufacturing technology. The program includes work in the following areas: Efforts in the casting area to increase ingot size, improve ingot material quality, and improve handling of silicon feedstock as it is loaded into the casting stations; developing wire saws to slice 100- m-thick silicon wafers on 290- m centers; developing equipment for demounting and subsequent handling of very thin silicon wafers; developing cell processes using 100- m-thick silicon wafers that produce encapsulated cells with efficiencies of at least 15.4% at an overall yield exceeding 95%; expanding existing in-line manufacturing data reporting systems to provide active process control; establishing a 50-MW (annual nominal capacity) green-field Mega-plant factory model template based on this new thin polycrystalline silicon technology; facilitating an increase in the silicon feedstock industry's production capacity for lower-cost solar-grade silicon feedstock.

  16. 78 FR 17668 - Federal Acquisition Regulation; Submission for OMB Review; Subcontracting Plans/Individual...

    Science.gov (United States)

    2013-03-22

    ... Regulation; Submission for OMB Review; Subcontracting Plans/Individual Subcontract Report (SF-294) AGENCY... previously approved information collection requirement concerning subcontracting plans/individual subcontract... identified by Information Collection ] 9000-0006, Subcontracting Plans/Individual Subcontract Report (SF-294...

  17. 78 FR 59798 - Small Business Subcontracting: Correction

    Science.gov (United States)

    2013-09-30

    ... ADMINISTRATION 13 CFR Part 125 RIN 3245-AG22 Small Business Subcontracting: Correction AGENCY: U.S. Small..., 2013 (78 FR 42391). The document amended SBA's regulations governing small business subcontracting to...-16967.pdf ). SBA published a final rule on subcontracting to implement provisions of the Small Business...

  18. 41 CFR 51-4.4 - Subcontracting.

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 1 2010-07-01 2010-07-01 true Subcontracting. 51-4.4... Subcontracting. (a) Nonprofit agencies shall seek broad competition in the purchase of materials and components... the JWOD Act. (b) Each nonprofit agency shall accomplish the maximum amount of subcontracting with...

  19. Photovoltaic Subcontract Program, FY 1991

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-01

    This report summarizes the fiscal year (FY) 1991 (October 1, 1990, through September 30, 1991) progress of the subcontracted photovoltaic (PV) research and development (R D) performed under the Photovoltaic Advanced Research and Development Project at the National Renewable Energy Laboratory (NREL) -- formerly the Solar Energy Research Institute (SERI). The mission of the national PV program is to develop PV technology for large-scale generation of economically competitive electric power in the United States. The technical sections of the report cover the main areas of the subcontract program: the Amorphous Silicon Research Project, Polycrystalline Thin Films, Crystalline Silicon Materials Research, High-Efficiency Concepts, the New Ideas Program, the University Participation Program, and the Photovoltaic Manufacturing Technology (PVMaT) project. Technical summaries of each of the subcontracted programs provide a discussion of approaches, major accomplishments in FY 1991, and future research directions.

  20. A Model of Safe Subcontracting

    DEFF Research Database (Denmark)

    Thommesen, Jacob; Andersen, Henning Boje

    This report is an excerpt from Deliverable D1.4.1.3 of EU Project iNTeg-Risk. The model presented here is the result of Task 1.4.1 of the iNTeg-Risk project that addressed safety problems related to outsourcing and subcontracting of safety-critical tasks. Concerns have been raised over the effects...... of the fragmentation of work processes associated with subcontracting and outsourcing, where safety may be affected by heterogeneous safety cultures, distributed lines of responsibility, unclear ownership of safety responsibility, and sometimes lack of local knowledge or lack of core skills....

  1. 48 CFR 2919.704 - Subcontracting plan requirements.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 7 2010-10-01 2010-10-01 false Subcontracting plan... Subcontracting Program 2919.704 Subcontracting plan requirements. Contracting Officers will refer subcontracting... that require subcontracting plans. Contracting officers will document the substance of any agreement...

  2. 77 FR 56644 - Federal Acquisition Regulation; Information Collection; Subcontract Consent

    Science.gov (United States)

    2012-09-13

    ... policy when subcontracting. The Government requires a contractor to provide certain information (e.g... of placing a subcontract to ensure that the proposed subcontract is appropriate for the risks...

  3. 77 FR 29983 - Federal Acquisition Regulation; Information Collection; Subcontract Consent

    Science.gov (United States)

    2012-05-21

    ... policy when subcontracting. The Government requires a contractor to provide certain information (e.g... of placing a subcontract to ensure that the proposed subcontract is appropriate for the risks...

  4. 77 FR 69626 - Federal Acquisition Regulation; Information Collection; Subcontracting Plans/Individual...

    Science.gov (United States)

    2012-11-20

    ... Regulation; Information Collection; Subcontracting Plans/Individual Subcontract Report (SF-294) AGENCIES... previously approved information collection requirement concerning subcontracting plans/individual subcontract... 22, 2013. ADDRESSES: Submit comments identified by Information Collection 9000- 0006, Subcontracting...

  5. 48 CFR 19.705-5 - Awards involving subcontracting plans.

    Science.gov (United States)

    2010-10-01

    ... subcontracting plans. 19.705-5 Section 19.705-5 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SOCIOECONOMIC PROGRAMS SMALL BUSINESS PROGRAMS The Small Business Subcontracting Program 19.705-5 Awards involving subcontracting plans. (a) In making an award that requires a subcontracting plan, the...

  6. 48 CFR 619.705-4 - Reviewing the subcontracting plan.

    Science.gov (United States)

    2010-10-01

    ... subcontracting plan. 619.705-4 Section 619.705-4 Federal Acquisition Regulations System DEPARTMENT OF STATE SOCIOECONOMIC PROGRAMS SMALL BUSINESS PROGRAMS The Small Business Subcontracting Program 619.705-4 Reviewing the subcontracting plan. A/SDBU shall review subcontracting plans to determine if small, small disadvantaged, women...

  7. 48 CFR 1319.705-4 - Reviewing the subcontracting plan.

    Science.gov (United States)

    2010-10-01

    ... subcontracting plan. 1319.705-4 Section 1319.705-4 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE SOCIOECONOMIC PROGRAMS SMALL BUSINESS PROGRAMS The Small Business Subcontracting Program 1319.705-4 Reviewing the subcontracting plan. The prime contractor's proposed subcontracting plan shall be reviewed by the...

  8. 48 CFR 219.704 - Subcontracting plan requirements.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Subcontracting plan... Subcontracting Program 219.704 Subcontracting plan requirements. (1) The goal for use of small disadvantaged... included in the small disadvantaged business goal in commercial items subcontracting plans. (2) In those...

  9. 48 CFR 819.704 - Subcontracting plan requirements.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Subcontracting plan... SOCIOECONOMIC PROGRAMS SMALL BUSINESS PROGRAMS The Small Business Subcontracting Program 819.704 Subcontracting plan requirements. (a) The contracting officer shall ensure that any subcontracting plans submitted by...

  10. 48 CFR 1052.219-71 - Subcontracting Plan.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Subcontracting Plan. 1052... Subcontracting Plan. As prescribed in DTAR 1019.708-70(b), insert the following provision: Subcontracting Plan..., as prescribed in FAR 52.219-9. Use of the subcontracting plan outlined containe in Section J of this...

  11. 48 CFR 219.705-4 - Reviewing the subcontracting plan.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Reviewing the subcontracting plan. 219.705-4 Section 219.705-4 Federal Acquisition Regulations System DEFENSE ACQUISITION... Subcontracting Program 219.705-4 Reviewing the subcontracting plan. (d) Challenge any subcontracting plan that...

  12. 48 CFR 2919.705-5 - Awards involving subcontracting plans.

    Science.gov (United States)

    2010-10-01

    ... subcontracting plans. 2919.705-5 Section 2919.705-5 Federal Acquisition Regulations System DEPARTMENT OF LABOR... Subcontracting Program 2919.705-5 Awards involving subcontracting plans. The Office of Small Business Programs will review subcontracting plans and SF 295 submissions for performance against business goals...

  13. 48 CFR 19.704 - Subcontracting plan requirements.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Subcontracting plan... SOCIOECONOMIC PROGRAMS SMALL BUSINESS PROGRAMS The Small Business Subcontracting Program 19.704 Subcontracting plan requirements. (a) Each subcontracting plan required under 19.702(a)(1) and (2) must include— (1...

  14. 48 CFR 52.219-10 - Incentive Subcontracting Program.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Incentive Subcontracting....219-10 Incentive Subcontracting Program. As prescribed in 19.708(c)(1), insert the following clause: Incentive Subcontracting Program (OCT 2001) (a) Of the total dollars it plans to spend under subcontracts...

  15. Ion Torren Semiconductor Sequencing Allows Rapid, Low Cost Sequencing of the Human Exome ( 7th Annual SFAF Meeting, 2012)

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, David [EdgeBio

    2012-06-01

    David Jenkins on "Ion Torrent semiconductor sequencing allows rapid, low-cost sequencing of the human exome" at the 2012 Sequencing, Finishing, Analysis in the Future Meeting held June 5-7, 2012 in Santa Fe, New Mexico.

  16. Optimization of Processing and Modeling Issues for Thin Film Solar Cell Devices Including Concepts for the Development of Polycrystalline Multijunctions Annual Subcontract Report, 24 August 1999 - 23 August 2000

    Energy Technology Data Exchange (ETDEWEB)

    Birkmire, R. W.; Phillips, J. E.; Shafarman, W. N.; Eser, E.; Hegedus, S. S.; McCandless, B. E.

    2001-11-14

    This report describes the results achieved during Phase I of a three-phase subcontract to develop and understand thin-film solar cell technology associated with CuInSe2 and related alloys, a-Si and its alloys, and CdTe. Modules based on all these thin films are promising candidates to meet DOE long-range efficiency, reliability, and manufacturing cost goals. The critical issues being addressed under this program are intended to provide the science and engineering basis for developing viable commercial processes and to improve module performance. The generic research issues addressed are: (1) quantitative analysis of processing steps to provide information for efficient commercial-scale equipment design and operation; (2) device characterization relating the device performance to materials properties and process conditions; (3) development of alloy materials with different bandgaps to allow improved device structures for stability and compatibility with module design; (4) development of improved window/heterojunction layers and contacts to improve device performance and reliability; and (5) evaluation of cell stability with respect to illumination, temperature, and ambient, and with respect to device structure and module encapsulation.

  17. Utilization of Small Businesses in Navy Subcontracting

    Science.gov (United States)

    2016-06-01

    subcontracting, and which were not It was found early on in the research most commands are not doing a good job ensuring required subcontracting plan...Firms conducting business with the federal government are required to take into account small-business concerns in the acquisition process. Subpart 19.7...2001 Submitted in partial fulfillment of the requirements for the degree of MASTER OF BUSINESS ADMINISTRATION from the NAVAL

  18. Twenty-Fifth Annual Conference on the Physics and Chemistry of Semiconductor Interfaces. Volume 16, Number 4

    Science.gov (United States)

    1998-08-01

    Canada, Micronet , a federal network center of excellence in microelectronics, and the National Council of Science and Technology (CONACyT) of...Semiconductor, Micronet , a federal network center of excel- lence in microelectronics and NSERC of Canada. The au- thors would also like to thank

  19. 75 FR 9604 - Federal Acquisition Regulation; Submission for OMB Review; Subcontracting Plans/Individual...

    Science.gov (United States)

    2010-03-03

    ... Regulation; Submission for OMB Review; Subcontracting Plans/Individual Subcontract Report AGENCIES... subcontracting plans/individual subcontract report. A request for public comments published in the Federal..., Washington, DC 20405. Please cite OMB Control No. 9000-0006, Subcontracting Plans/Individual Subcontract...

  20. Subcontracting Requirements and the Cost of Government Procurement

    OpenAIRE

    Rosa, Benjamin

    2016-01-01

    Government procurement auctions can be subject to policies that specify, as a percentage of the total project, a subcontracting requirement for the utilization of historically disadvantaged firms. This paper studies how these subcontracting policies affect auction outcomes using administrative data from New Mexico’s Disadvantaged Business Enterprise (DBE) program. Through the use of a procurement auction model with endogenous subcontracting, I show that subcontracting requirements need not co...

  1. Innovative Management in Subcontracting Business in Growing and Stagnating Economies

    OpenAIRE

    Karl-Heinz SCHMIDT

    2010-01-01

    The worldwide economic recession demonstrates: innovations are needed to increase productivity and competitivity of enterprises, especially of subcontracting companies. The paper compares the subcontracting business at a boom- and recession-phase, mainly in Japan and Germany. For Japan the components of subcontracting systems are exposed by a static and dynamic view. Changes of subcontracting firms from dependent, but stable suppliers of parts and services to extremely dependent subcontractor...

  2. FIDIC Conditions of Subcontract as a Model for General Conditions of Subcontract in Pakistan

    Directory of Open Access Journals (Sweden)

    Muhammad Umer Zubair

    2016-12-01

    Full Text Available Fair allocation of risks in conditions of contract is pivotal for coordination, unhindered execution, dispute resolution and maintenance of positive relationship among the parties executing the contract. Pakistani construction industry despite subcontracting a large percentage of construction projects lacks standard conditions of subcontract and they are primarily based on the will of the prime contractor that is onerous for the subcontractor. Therefore in order to develop a model for the general conditions of subcontract in Pakistan the conditions proposed by Associated General Contractors of California, FIDIC in 1994 and 2011, Construction Industry Development Board Malaysia, American Institute of Architects and by the Government of Hong Kong were compared to determine the similarities and differences among them. Afterwards a questionnaire based on the significant provisions of these subcontracts was conducted in the construction industry of Pakistan to determine the appropriate conditions for model subcontract. The results of the survey were further subjected to discussions with the legal experts. Out of 35 suggestions made for the general conditions of subcontract 23 originated from FIDIC in which 20 are recommended by its 2011’s version. It can therefore be implemented in Pakistan with certain amendments and additions as proposed in light of conditions of other subcontracts and the results of the survey and discussions with legal experts.

  3. 48 CFR 1519.705-4 - Reviewing the subcontracting plan.

    Science.gov (United States)

    2010-10-01

    ... subcontracting plan. 1519.705-4 Section 1519.705-4 Federal Acquisition Regulations System ENVIRONMENTAL PROTECTION AGENCY SOCIOECONOMIC PROGRAMS SMALL BUSINESS PROGRAMS Subcontracting With Small Business and Small Disadvantaged Business Concerns 1519.705-4 Reviewing the subcontracting plan. In determining the acceptability...

  4. 48 CFR 2019.705-4 - Reviewing the subcontracting plan.

    Science.gov (United States)

    2010-10-01

    ... subcontracting plan. 2019.705-4 Section 2019.705-4 Federal Acquisition Regulations System NUCLEAR REGULATORY COMMISSION SOCIOECONOMIC PROGRAMS SMALL BUSINESS PROGRAMS Subcontracting With Small Business, Small Disadvantaged Business, and Women-Owned Small Business Concerns 2019.705-4 Reviewing the subcontracting plan...

  5. 48 CFR 319.705-5 - Awards involving subcontracting plans.

    Science.gov (United States)

    2010-10-01

    ... subcontracting plans. 319.705-5 Section 319.705-5 Federal Acquisition Regulations System HEALTH AND HUMAN SERVICES SOCIOECONOMIC PROGRAMS SMALL BUSINESS PROGRAMS Subcontracting With Small Business, Small Disadvantaged Business, and Women-Owned Small Business Concerns 319.705-5 Awards involving subcontracting plans...

  6. 48 CFR 809.405-2 - Restrictions on subcontracting.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Restrictions on subcontracting. 809.405-2 Section 809.405-2 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS....405-2 Restrictions on subcontracting. When a subcontract is subject to Government consent, authority...

  7. 23 CFR 635.116 - Subcontracting and contractor responsibilities.

    Science.gov (United States)

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Subcontracting and contractor responsibilities. 635.116... TRAFFIC OPERATIONS CONSTRUCTION AND MAINTENANCE Contract Procedures § 635.116 Subcontracting and..., requirement or preference shall be imposed which prescribes minimum subcontracting requirements or goals...

  8. 48 CFR 9.405-2 - Restrictions on subcontracting.

    Science.gov (United States)

    2010-10-01

    ... subcontracting. 9.405-2 Section 9.405-2 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION... on subcontracting. (a) When a contractor debarred, suspended, or proposed for debarment is proposed... ineligibility affecting subcontracting.) (b) The Government suspends or debars contractors to protect the...

  9. 48 CFR 52.244-5 - Competition in Subcontracting.

    Science.gov (United States)

    2010-10-01

    ... Subcontracting. 52.244-5 Section 52.244-5 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION....244-5 Competition in Subcontracting. As prescribed in 44.204(c), insert the following clause: Competition in Subcontracting (DEC 1996) (a) The Contractor shall select subcontractors (including suppliers...

  10. 48 CFR 970.1907-1 - Subcontracting plan requirements.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Subcontracting plan... Small Business Concerns 970.1907-1 Subcontracting plan requirements. Pursuant to the clause at 48 CFR 52.219-9, Small Business Subcontracting Plan, which is required for all management and operating...

  11. 48 CFR 726.7008 - Limitations on subcontracting.

    Science.gov (United States)

    2010-10-01

    ... subcontracting. 726.7008 Section 726.7008 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL... Limitations on subcontracting. The contracting officer shall insert the clause at 752.226-3, Limitations on Subcontracting, in any solicitation and contract for technical assistance services which is to be awarded under...

  12. 48 CFR 409.405-2 - Restrictions on subcontracting.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Restrictions on subcontracting. 409.405-2 Section 409.405-2 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE...-2 Restrictions on subcontracting. The HCA is authorized to approve subcontracts with debarred or...

  13. 48 CFR 225.871-5 - Directed Subcontracting.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Directed Subcontracting... and Coordination 225.871-5 Directed Subcontracting. (a) The Director of Defense Procurement and... subcontracting is not authorized unless specifically addressed in the cooperative project agreement. (b) In some...

  14. 48 CFR 5.206 - Notices of subcontracting opportunities.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Notices of subcontracting... subcontracting opportunities. (a) The following entities may transmit a notice to the GPE to seek competition for... concerns, and to meet established subcontracting plan goals: (1) A contractor awarded a contract exceeding...

  15. 48 CFR 1644.170 - Policy for FEHB Program subcontracting.

    Science.gov (United States)

    2010-10-01

    ... subcontracting. 1644.170 Section 1644.170 Federal Acquisition Regulations System OFFICE OF PERSONNEL MANAGEMENT FEDERAL EMPLOYEES HEALTH BENEFITS ACQUISITION REGULATION CONTRACT MANAGEMENT SUBCONTRACTING POLICIES AND PROCEDURES General 1644.170 Policy for FEHB Program subcontracting. (a) General policy. Carriers must follow...

  16. 48 CFR 1852.219-75 - Small business subcontracting reporting.

    Science.gov (United States)

    2010-10-01

    ... subcontracting reporting. 1852.219-75 Section 1852.219-75 Federal Acquisition Regulations System NATIONAL... Provisions and Clauses 1852.219-75 Small business subcontracting reporting. As prescribed in 1819.708-70(b), insert the following clause: Small Business Subcontracting Reporting (MAY 1999) (a) The Contractor shall...

  17. 48 CFR 752.226-3 - Limitation on subcontracting.

    Science.gov (United States)

    2010-10-01

    ... subcontracting. 752.226-3 Section 752.226-3 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL....226-3 Limitation on subcontracting. As prescribed in 726.7008, insert the following clause: Limitations on Subcontracting (JUN 1993) By submission of an offer and execution of a contract, the Offeror...

  18. 24 CFR 115.309 - Subcontracting under the FHAP.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Subcontracting under the FHAP. 115.309 Section 115.309 Housing and Urban Development Regulations Relating to Housing and Urban... Housing Assistance Program § 115.309 Subcontracting under the FHAP. If an agency subcontracts to a public...

  19. 48 CFR 35.009 - Subcontracting research and development effort.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Subcontracting research... Subcontracting research and development effort. Since the selection of R&D contractors is substantially based on... concerning the contractor's plans for subcontracting any portion of the experimental, research, or...

  20. 48 CFR 752.226-2 - Subcontracting with disadvantaged enterprises.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Subcontracting with... Clauses 752.226-2 Subcontracting with disadvantaged enterprises. As prescribed in 726.7007, insert the following clause: Subcontracting With Disadvantaged Enterprises (APR 1997) Note: This clause does not apply...

  1. 48 CFR 52.219-14 - Limitations on Subcontracting.

    Science.gov (United States)

    2010-10-01

    ... Subcontracting. 52.219-14 Section 52.219-14 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION....219-14 Limitations on Subcontracting. As prescribed in 19.508(e) or 19.811-3(e), insert the following clause: Limitations on Subcontracting (DEC 1996) (a) This clause does not apply to the unrestricted...

  2. 48 CFR 1852.219-73 - Small business subcontracting plan.

    Science.gov (United States)

    2010-10-01

    ... Provisions and Clauses 1852.219-73 Small business subcontracting plan. As prescribed in 1819.708-70(a), insert the following provision: Small Business Subcontracting Plan (MAY 1999) (a) This provision is not... contain FAR clause 52.219-9, “Small Business Subcontracting Plan.” The apparent low bidder must submit the...

  3. Measurement techniques for high-power semiconductor materials and devices. Annual report, October 1, 1980-December 31, 1981. [For calculating excess-carrier lifetime in silicon

    Energy Technology Data Exchange (ETDEWEB)

    Thurber, W R; Phillips, W E; Larrabee, R D

    1982-08-01

    This annual report describes results of NBS research directed toward the development of measurement methods for semiconductor materials and devices which will lead to more effective use of high-power semiconductor devices in applications for energy generation, transmission, conversion, and conservation. Emphasis is on the development of measurement methods for power-device-grade silicon. Major accomplishments during this reporting period were : (1) characterizing by deep level transient spectroscopy (DLTS) the energy levels in silicon power rectifier diodes, (2) writing of a computer program to predict lifetime-related parameters using as input the measured properties of the deep energy levels, (3) developing a novel method to detect nonexponential transients using a conventional double-boxcar DLTS system, (4) analyzing transient capacitance measurements to extend the techniques to nonexponential decays, (5) using a platinum resistance thermometer to calibrate temperature sensing diodes to obtain the precision needed for careful isothermal capacitance measurements, and (6) utilizing trap changing time as a technique to resolve overlapping DLTS peaks in sulfur-doped silicon.

  4. Photovoltaic Program Branch annual report, FY 1989

    Energy Technology Data Exchange (ETDEWEB)

    Summers, K A [ed.

    1990-03-01

    This report summarizes the progress of the Photovoltaic (PV) Program Branch of the Solar Energy Research Institute (SERI) from October 1, 1988, through September 30, 1989. The branch is responsible for managing the subcontracted portion of SERI's PV Advanced Research and Development Project. In fiscal year (FY) 1989, this included nearly 50 subcontracts, with a total annualized funding of approximately $13.1 million. Approximately two-thirds of the subcontracts were with universities, at a total funding of nearly $4 million. The six technical sections of the report cover the main areas of the subcontracted program: Amorphous Silicon Research, Polycrystalline Thin Films, Crystalline Silicon Materials Research, High-Efficiency Concepts, New Ideas, and University Participation. Technical summaries of each of the subcontracted programs provide a discussion of approaches, major accomplishments in FY 1989, and future research directions. Each report will be cataloged individually.

  5. FIDIC Conditions of Subcontract as a Model for General Conditions of Subcontract in Pakistan

    OpenAIRE

    Muhammad Umer Zubair; Hamza Farooq Gabriel; Muhamamd Jamaluddin Thaheem; Muhammad Bilal Khurshid; Ammara Mubeen

    2016-01-01

    Fair allocation of risks in conditions of contract is pivotal for coordination, unhindered execution, dispute resolution and maintenance of positive relationship among the parties executing the contract. Pakistani construction industry despite subcontracting a large percentage of construction projects lacks standard conditions of subcontract and they are primarily based on the will of the prime contractor that is onerous for the subcontractor. Therefore in order to develop a model for the gen...

  6. Identifying electronic properties relevant to improving stability in a-Si:H-based cells and overall performance in a-Si,Ge:H-based cells. Annual subcontract report, April 18, 1994--April 17, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, J D [Oregon Univ., Eugene, OR (United States)

    1995-11-01

    This report describes work performed by the University of Oregon focusing on the characterization and evaluation of amorphous semiconductor materials produced by novel deposition conditions and/or methods. The results are based on a variety of junction capacitance techniques: admittance spectroscopy, transient photocapacitance (and photocurrent), and drive-level capacitance profiling. These methods allow the determination of deep defect densities and their energy distributions, Urbach bandtail energies, and, in some cases, {mu}{tau} products for hole transport. During this phase, the authors completed several tasks: (1) they carried out measurements on a-Si, Ge:H alloy samples produced at Harvard University by a cathodic glow discharge process, measurement indicated a smaller value of ({mu}{tau}){sub h} for these samples than would have been expected given their lower defect densities; (2) they characterized several hot-wire a-Si:H samples produced with varying hydrogen levels, studies indicate that hot-wire-produced a-Si:H, with H levels between 2--5 at.% should lead to mid-gap devices with superior properties; (3) they reported some results on a-Si:H glow discharge material grown under hydrogen dilution conditions. Preliminary studies point to film strain as playing a primary role for the observed differences in behavior.

  7. Subcontracting in State and Local Government Employment.

    Science.gov (United States)

    Staudohar, Paul D.

    1980-01-01

    Contracting out has cut government costs and raised service levels in many cases. It has, however, also been associated with waste, inefficiency, and graft. Legal and contractual protections may insure public employees against loss of work or reduction in benefits from subcontracting. (Author/IRT)

  8. 48 CFR 1419.705 - Responsibilities of the contracting officer under the subcontracting assistance program.

    Science.gov (United States)

    2010-10-01

    ... contracting officer under the subcontracting assistance program. 1419.705 Section 1419.705 Federal Acquisition... Business Subcontracting Program 1419.705 Responsibilities of the contracting officer under the subcontracting assistance program. ...

  9. 48 CFR 3019.705 - Responsibilities for the contracting officer under the subcontracting program.

    Science.gov (United States)

    2010-10-01

    ... contracting officer under the subcontracting program. 3019.705 Section 3019.705 Federal Acquisition...) SOCIOECONOMIC PROGRAMS SMALL BUSINESS PROGRAMS The Small Business Subcontracting Program 3019.705 Responsibilities for the contracting officer under the subcontracting program. ...

  10. 48 CFR 319.705 - Responsibilities of the Contracting Officer under the subcontracting assistance program.

    Science.gov (United States)

    2010-10-01

    ... Contracting Officer under the subcontracting assistance program. 319.705 Section 319.705 Federal Acquisition Regulations System HEALTH AND HUMAN SERVICES SOCIOECONOMIC PROGRAMS SMALL BUSINESS PROGRAMS Subcontracting... Responsibilities of the Contracting Officer under the subcontracting assistance program. ...

  11. 78 FR 13546 - Defense Federal Acquisition Regulation Supplement; Electronic Subcontracting Reporting System

    Science.gov (United States)

    2013-02-28

    ... Regulation Supplement; Electronic Subcontracting Reporting System AGENCY: Defense Acquisition Regulations... the FAR regarding policy and procedures related to the Electronic Subcontracting Reporting System... procedures and policies related to the Electronic Subcontracting Reporting System (eSRS). There were no...

  12. 48 CFR 219.705 - Responsibilities of the contracting officer under the subcontracting assistance program.

    Science.gov (United States)

    2010-10-01

    ... contracting officer under the subcontracting assistance program. 219.705 Section 219.705 Federal Acquisition... BUSINESS PROGRAMS The Small Business Subcontracting Program 219.705 Responsibilities of the contracting officer under the subcontracting assistance program. ...

  13. 48 CFR 2019.705 - Responsibilities of the contracting officer under the subcontracting assistance program.

    Science.gov (United States)

    2010-10-01

    ... contracting officer under the subcontracting assistance program. 2019.705 Section 2019.705 Federal Acquisition Regulations System NUCLEAR REGULATORY COMMISSION SOCIOECONOMIC PROGRAMS SMALL BUSINESS PROGRAMS Subcontracting... Responsibilities of the contracting officer under the subcontracting assistance program. ...

  14. Formal sector subcontracting and informal sector employment in Indian manufacturing

    National Research Council Canada - National Science Library

    Moreno-Monroy, A.I; Pieters, J; Erumban, A.A

    2014-01-01

    Using nationally representative survey dta of Indian manufacturing enterprises spanning the period 1995-2006, we analyze the link between formal sector subcontracting and informal sector employment...

  15. Semiconductor physics

    Energy Technology Data Exchange (ETDEWEB)

    Tuchkevich, V.M.; Frenkel, V.Y.

    1986-01-01

    This text is a collection of papers devoted mainly to the results of the research work in the field of semiconductors. Topics include photovoltaic solar energy conversion, interacting excitons in germanium and silicon, chalcogenide vitreous semiconductors, optical cooling of the nuclear spin system in a semiconductor, photon drag of electrons in semiconductors, dielectric losses in crystals, light scattering from heavily doped semiconductors, and the capacity of an abrupt asymmetric p-n junction.

  16. 48 CFR 52.244-6 - Subcontracts for Commercial Items.

    Science.gov (United States)

    2010-10-01

    ... clauses in subcontracts for commercial items: (i) 52.203-13, Contractor Code of Business Ethics and... Recovery Act. (iii) 52.219-8, Utilization of Small Business Concerns (MAY 2004) (15 U.S.C. 637(d)(2) and (3... subcontracts to small business concerns) exceeds $650,000 ($1.5 million for construction of any public facility...

  17. 48 CFR 509.405-2 - Restrictions on subcontracting.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Restrictions on subcontracting. 509.405-2 Section 509.405-2 Federal Acquisition Regulations System GENERAL SERVICES... Ineligibility 509.405-2 Restrictions on subcontracting. The responsibilities of the agency head under FAR 9.405...

  18. 48 CFR 609.405-2 - Restrictions on subcontracting.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Restrictions on subcontracting. 609.405-2 Section 609.405-2 Federal Acquisition Regulations System DEPARTMENT OF STATE....405-2 Restrictions on subcontracting. The Procurement Executive is the agency head's designee for the...

  19. 48 CFR 2009.405-2 - Restrictions on subcontracting.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Restrictions on subcontracting. 2009.405-2 Section 2009.405-2 Federal Acquisition Regulations System NUCLEAR REGULATORY... Ineligibility 2009.405-2 Restrictions on subcontracting. The Head of the Contracting Activity is authorized to...

  20. 48 CFR 209.405-2 - Restrictions on subcontracting.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Restrictions on subcontracting. 209.405-2 Section 209.405-2 Federal Acquisition Regulations System DEFENSE ACQUISITION..., and Ineligibility 209.405-2 Restrictions on subcontracting. (a) The contracting officer shall not...

  1. 48 CFR 2509.405-2 - Restrictions on subcontracting.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Restrictions on subcontracting. 2509.405-2 Section 2509.405-2 Federal Acquisition Regulations System NATIONAL SCIENCE FOUNDATION... Restrictions on subcontracting. The NSF Deputy Director may authorize a contracting officer to consent to a...

  2. Research Subcontracting: Taking the Worry out of Being Close.

    Science.gov (United States)

    Erickson, Stephen

    1987-01-01

    Writing and administering proper subcontracts are essential components of effective grant and contract management. Frequently, prime grantees and contractors issue letters, simple purchase orders, or other brief documents in order to establish subcontracting relationships. The reason why these are not adequate is explained. (MLW)

  3. 48 CFR 1309.405-2 - Restrictions on subcontracting.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Restrictions on subcontracting. 1309.405-2 Section 1309.405-2 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE....405-2 Restrictions on subcontracting. The designee authorized to provide, in writing, compelling...

  4. 24 CFR 882.412 - Subcontracting of owner services.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Subcontracting of owner services. 882.412 Section 882.412 Housing and Urban Development Regulations Relating to Housing and Urban... Moderate Rehabilitation-Basic Policies § 882.412 Subcontracting of owner services. (a) General. Any Owner...

  5. Sub-Contracting in Rural Areas of Thailand

    OpenAIRE

    Mead, Donald C.

    1982-01-01

    This paper describes an arrangement where a producer undertakes certain steps in the production process done by individuals working in their own homes in Thailand. The paper also provides a description of how this system operates in four different industries, presents survey data on people engaged in subcontracting work, evaluates the subcontracting system, and determines the advantages and disadvantages of its operation.

  6. 48 CFR 970.5227-6 - Patent indemnity-subcontracts.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Patent indemnity... for Management and Operating Contracts 970.5227-6 Patent indemnity—subcontracts. Insert the following clause in solicitations and contracts in accordance with 970.2702-3: Patent Indemnity—Subcontracts (DEC...

  7. 48 CFR 52.219-9 - Small business subcontracting plan.

    Science.gov (United States)

    2010-10-01

    ... Clauses 52.219-9 Small business subcontracting plan. As prescribed in 19.708(b), insert the following clause: Small Business Subcontracting Plan (OCT 2010) (a) This clause does not apply to small business... business, and women-owned small business concerns. If the offeror is submitting an individual contract plan...

  8. 48 CFR 226.370-8 - Goals and incentives for subcontracting with HBCU/MIs.

    Science.gov (United States)

    2010-10-01

    ... subcontracting with HBCU/MIs. 226.370-8 Section 226.370-8 Federal Acquisition Regulations System DEFENSE... subcontracting with HBCU/MIs. (a) In reviewing subcontracting plans submitted under the clause at FAR 52.219-9, Small Business Subcontracting Plan, the contracting officer shall— (1) Ensure that the contractor...

  9. 48 CFR 1419.705-2 - Determining the need for a subcontracting plan.

    Science.gov (United States)

    2010-10-01

    ... subcontracting plan. 1419.705-2 Section 1419.705-2 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR SOCIOECONOMIC PROGRAMS SMALL BUSINESS PROGRAMS The Small Business Subcontracting Program 1419.705-2 Determining the need for a subcontracting plan. The CO's determination that no subcontract...

  10. Semiconductor statistics

    CERN Document Server

    Blakemore, J S

    1987-01-01

    In-depth exploration of the implications of carrier populations and Fermi energies examines distribution of electrons in energy bands and impurity levels of semiconductors. Also: kinetics of semiconductors containing excess carriers, particularly in terms of trapping, excitation, and recombination.

  11. Semiconductor physics

    CERN Document Server

    Böer, Karl W

    2018-01-01

    This handbook gives a complete survey of the important topics and results in semiconductor physics. It addresses every fundamental principle and most research topics and areas of application in the field of semiconductor physics. Comprehensive information is provided on crystalline bulk and low-dimensional as well as amporphous semiconductors, including optical, transport, and dynamic properties.

  12. 48 CFR 212.7002-2 - Subcontracts under the program.

    Science.gov (United States)

    2010-10-01

    ... REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE ACQUISITION PLANNING ACQUISITION OF COMMERCIAL ITEMS Pilot Program... “commercial item” may be treated as a subcontract for a commercial item, if the subcontract— (1) Is for the...

  13. 48 CFR 19.705-4 - Reviewing the subcontracting plan.

    Science.gov (United States)

    2010-10-01

    ... officer shall determine whether the plan is acceptable based on the negotiation of each of the 11 elements... does not conflict with the offeror's proposed subcontracting plan and is in the Government's interest...

  14. 48 CFR 52.209-6 - Protecting the Government's Interest When Subcontracting With Contractors Debarred, Suspended, or...

    Science.gov (United States)

    2010-10-01

    ...'s Interest When Subcontracting With Contractors Debarred, Suspended, or Proposed for Debarment. 52....209-6 Protecting the Government's Interest When Subcontracting With Contractors Debarred, Suspended... Government's Interest When Subcontracting With Contractors Debarred, Suspended, or Proposed for Debarment...

  15. The nexus between OSH and subcontracting.

    Science.gov (United States)

    Nunes, Isabel L

    2012-01-01

    Subcontracting of specialized functions to external companies (e.g. cleaning or maintenance) is actually very common within several industries. These external companies' are called contractors and their contracting is often designated as outsourcing. Frequently contractors involve other companies (the sub-contractors) to assist them in fulfilling the contract, resulting in a complex chain of organizations focused on interchange of work - the contracting chain. Therefore in the same work site can coexist workers form the client-company and workers from the contractors and/or subcontractors. Since contractors perform their job in client's facilities, they can be exposed to hazards that are unknown to them. On other hand, workers of the client company can also be exposed to hazardous situations derived from the work performed by the contractors. The paper discusses how adequate occupational safety and health conditions can be assured when dealing with this kind of dynamic labor networks. Two case-studies and several examples coming from international literature will be presented.

  16. Semiconductor spintronics

    CERN Document Server

    Xia, Jianbai; Chang, Kai

    2012-01-01

    Semiconductor Spintronics, as an emerging research discipline and an important advanced field in physics, has developed quickly and obtained fruitful results in recent decades. This volume is the first monograph summarizing the physical foundation and the experimental results obtained in this field. With the culmination of the authors' extensive working experiences, this book presents the developing history of semiconductor spintronics, its basic concepts and theories, experimental results, and the prospected future development. This unique book intends to provide a systematic and modern foundation for semiconductor spintronics aimed at researchers, professors, post-doctorates, and graduate students, and to help them master the overall knowledge of spintronics.

  17. Macroporous Semiconductors

    Directory of Open Access Journals (Sweden)

    Helmut Föll

    2010-05-01

    Full Text Available Pores in single crystalline semiconductors come in many forms (e.g., pore sizes from 2 nm to > 10 µm; morphologies from perfect pore crystal to fractal and exhibit many unique properties directly or as nanocompounds if the pores are filled. The various kinds of pores obtained in semiconductors like Ge, Si, III-V, and II-VI compound semiconductors are systematically reviewed, emphasizing macropores. Essentials of pore formation mechanisms will be discussed, focusing on differences and some open questions but in particular on common properties. Possible applications of porous semiconductors, including for example high explosives, high efficiency electrodes for Li ion batteries, drug delivery systems, solar cells, thermoelectric elements and many novel electronic, optical or sensor devices, will be introduced and discussed.

  18. 48 CFR 552.219-72 - Preparation, Submission, and Negotiation of Subcontracting Plans.

    Science.gov (United States)

    2010-10-01

    ..., and Negotiation of Subcontracting Plans. 552.219-72 Section 552.219-72 Federal Acquisition Regulations... Text of Provisions and Clauses 552.219-72 Preparation, Submission, and Negotiation of Subcontracting... Negotiation of Subcontracting Plans (JUN 2005) (a) An offeror, other than a small business concern, submitting...

  19. 48 CFR 652.219-70 - Department of State Subcontracting Goals.

    Science.gov (United States)

    2010-10-01

    ... Subcontracting Goals. 652.219-70 Section 652.219-70 Federal Acquisition Regulations System DEPARTMENT OF STATE... Department of State Subcontracting Goals. As prescribed in 619.708-70, insert a provision substantially the same as follows: Department of State Subcontracting Goals (APR 2004) (a) The offeror shall provide a...

  20. 48 CFR 952.225-70 - Subcontracting for nuclear hot cell services.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Subcontracting for nuclear....225-70 Subcontracting for nuclear hot cell services. As prescribed in 925.7004, insert the following clause in solicitations and contracts: Subcontracting for Nuclear Hot Cell Services (MAR 1993) (a...

  1. 48 CFR 19.705 - Responsibilities of the contracting officer under the subcontracting assistance program.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Responsibilities of the contracting officer under the subcontracting assistance program. 19.705 Section 19.705 Federal Acquisition... Business Subcontracting Program 19.705 Responsibilities of the contracting officer under the subcontracting...

  2. 48 CFR 3419.705-2 - Determining the need for a subcontracting plan.

    Science.gov (United States)

    2010-10-01

    ... subcontracting plan. 3419.705-2 Section 3419.705-2 Federal Acquisition Regulations System DEPARTMENT OF EDUCATION... Subcontracting With Small Business and Small Disadvantaged Business Concerns 3419.705-2 Determining the need for a subcontracting plan. Incremental funding actions must be included in determining whether an...

  3. 48 CFR 1319.705 - Responsibilities of the contracting officer under the subcontracting assistance program.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Responsibilities of the contracting officer under the subcontracting assistance program. 1319.705 Section 1319.705 Federal Acquisition... Subcontracting Program 1319.705 Responsibilities of the contracting officer under the subcontracting assistance...

  4. 48 CFR 19.705-2 - Determining the need for a subcontracting plan.

    Science.gov (United States)

    2010-10-01

    ... subcontracting plan. 19.705-2 Section 19.705-2 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SOCIOECONOMIC PROGRAMS SMALL BUSINESS PROGRAMS The Small Business Subcontracting Program 19.705-2 Determining the need for a subcontracting plan. The contracting officer must take the following actions to...

  5. 48 CFR 726.7007 - Requirement for subcontracting with disadvantaged enterprises.

    Science.gov (United States)

    2010-10-01

    ... subcontracting with disadvantaged enterprises. 726.7007 Section 726.7007 Federal Acquisition Regulations System... Enterprises Program 726.7007 Requirement for subcontracting with disadvantaged enterprises. (a) In addition to... is no realistic expectation of U.S. subcontracting opportunities and so documents the file. If the...

  6. 48 CFR 225.872-8 - Subcontracting with qualifying country sources.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Subcontracting with... International Agreements and Coordination 225.872-8 Subcontracting with qualifying country sources. In reviewing contractor subcontracting procedures, the contracting officer shall ensure that the contract does not...

  7. 77 FR 69483 - Federal Acquisition Regulation; Information Collection; Summary Subcontract Report

    Science.gov (United States)

    2012-11-19

    ... subcontracting plan that provides maximum practicable opportunities for the above named concerns. Specific... are implemented in FAR Subpart 19.7. In conjunction with the subcontracting plan requirements... subcontractors for a specific Federal Government agency that required an Individual Subcontracting plan for the...

  8. 48 CFR 3052.219-70 - Small Business subcontracting program reporting.

    Science.gov (United States)

    2010-10-01

    ... subcontracting program reporting. 3052.219-70 Section 3052.219-70 Federal Acquisition Regulations System... subcontracting program reporting. As prescribed in (HSAR) 48 CFR 3019.708-70(a), insert the following clause: Small Business Subcontracting Plan Reporting (JUN 2006) (a) The Contractor shall enter the information...

  9. 48 CFR 19.1203 - Incentive subcontracting with small disadvantaged business concerns.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Incentive subcontracting... Business Participation Program 19.1203 Incentive subcontracting with small disadvantaged business concerns. The contracting officer may encourage increased subcontracting opportunities in the NAICS Industry...

  10. 77 FR 56709 - Proposed Information Collection (VA Subcontracting Report for Service Disabled Veteran-Owned...

    Science.gov (United States)

    2012-09-13

    ... Information Collection (VA Subcontracting Report for Service Disabled Veteran-Owned Small Business and Veteran... needed to collect information from subcontractors to compare information obtained from subcontracting... collection techniques or the use of other forms of information technology. Title: VA Subcontracting Report...

  11. 48 CFR 219.1203 - Incentive subcontracting with small disadvantaged business concerns.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Incentive subcontracting... BUSINESS PROGRAMS Small Disadvantaged Business Participation Program 219.1203 Incentive subcontracting with small disadvantaged business concerns. The contracting officer shall encourage increased subcontracting...

  12. 48 CFR 52.219-16 - Liquidated Damages-Subcontracting Plan.

    Science.gov (United States)

    2010-10-01

    ...-Subcontracting Plan. 52.219-16 Section 52.219-16 Federal Acquisition Regulations System FEDERAL ACQUISITION... Clauses 52.219-16 Liquidated Damages—Subcontracting Plan. As prescribed in 19.708(b)(2), insert the following clause: Liquidated Damages—Subcontracting Plan (JAN 1999) (a) Failure to make a good faith effort...

  13. 75 FR 65439 - Defense Federal Acquisition Regulation Supplement; Electronic Subcontracting Reporting System

    Science.gov (United States)

    2010-10-25

    ... Supplement; Electronic Subcontracting Reporting System AGENCY: Defense Acquisition Regulations System... Electronic Subcontracting Reporting System (eSRS). The FAR has been revised to reflect use of the eSRS... Subcontracting Reporting System. This DFARS interim rule amends sections 219.708 and 252.219 to provide DoD...

  14. 48 CFR 3419.705 - Responsibilities of the contracting officer under the subcontracting assistance program.

    Science.gov (United States)

    2010-10-01

    ... contracting officer under the subcontracting assistance program. 3419.705 Section 3419.705 Federal Acquisition... SMALL DISADVANTAGED BUSINESS CONCERNS Subcontracting With Small Business and Small Disadvantaged Business Concerns 3419.705 Responsibilities of the contracting officer under the subcontracting assistance...

  15. 13 CFR 125.6 - Prime contractor performance requirements (limitations on subcontracting).

    Science.gov (United States)

    2010-01-01

    ... requirements (limitations on subcontracting). 125.6 Section 125.6 Business Credit and Assistance SMALL BUSINESS... subcontracting). (a) In order to be awarded a full or partial small business set-aside contract, an 8(a) contract... contract in a HUBZone. One or more qualified HUBZone SBCs may combine to meet this subcontracting...

  16. 48 CFR 552.219-71 - Notice to Offerors of Subcontracting Plan Requirements.

    Science.gov (United States)

    2010-10-01

    ... Subcontracting Plan Requirements. 552.219-71 Section 552.219-71 Federal Acquisition Regulations System GENERAL... and Clauses 552.219-71 Notice to Offerors of Subcontracting Plan Requirements. As prescribed in 519.708-70(a), insert the following provision: Notice to Offerors of Subcontracting Plan Requirements (JUN...

  17. 48 CFR 52.219-26 - Small Disadvantaged Business Participation Program-Incentive Subcontracting.

    Science.gov (United States)

    2010-10-01

    ... Business Participation Program-Incentive Subcontracting. 52.219-26 Section 52.219-26 Federal Acquisition... Program—Incentive Subcontracting. As prescribed in 19.1204(c), insert a clause substantially the same as the following: Small Disadvantaged Business Participation Program—Incentive Subcontracting (OCT 2000...

  18. 13 CFR 126.701 - Can these subcontracting percentages requirements change?

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Can these subcontracting... ADMINISTRATION HUBZONE PROGRAM Contract Performance Requirements § 126.701 Can these subcontracting percentages requirements change? Yes. The Administrator may change the subcontracting percentage requirements if the...

  19. 13 CFR 126.702 - How can the subcontracting percentage requirements be changed?

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false How can the subcontracting... ADMINISTRATION HUBZONE PROGRAM Contract Performance Requirements § 126.702 How can the subcontracting percentage requirements be changed? SBA may change the required subcontracting percentage for a specific industry if the...

  20. 48 CFR 619.705 - Responsibilities of the contracting officer under the subcontracting assistance program.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Responsibilities of the contracting officer under the subcontracting assistance program. 619.705 Section 619.705 Federal Acquisition... Subcontracting Program 619.705 Responsibilities of the contracting officer under the subcontracting assistance...

  1. 77 FR 70210 - Agency Information Collection (VA Subcontracting Report for Service Disabled Veteran-owned Small...

    Science.gov (United States)

    2012-11-23

    ... AFFAIRS Agency Information Collection (VA Subcontracting Report for Service Disabled Veteran-owned Small....'' SUPPLEMENTARY INFORMATION: Title: VA Subcontracting Report for Service Disabled Veteran-owned Small Business and... from subcontractors to compare information obtained from subcontracting plans submitted by prime...

  2. 48 CFR 952.226-72 - Energy Policy Act subcontracting goals and reporting requirements.

    Science.gov (United States)

    2010-10-01

    ... subcontracting goals and reporting requirements. 952.226-72 Section 952.226-72 Federal Acquisition Regulations... Provisions and Clauses 952.226-72 Energy Policy Act subcontracting goals and reporting requirements. As prescribed in 926.7007(c), insert the following clause: Energy Policy Act Subcontracting Goals and Reporting...

  3. 48 CFR 52.226-5 - Restrictions on Subcontracting Outside Disaster or Emergency Area.

    Science.gov (United States)

    2010-10-01

    ... Subcontracting Outside Disaster or Emergency Area. 52.226-5 Section 52.226-5 Federal Acquisition Regulations... CLAUSES Text of Provisions and Clauses 52.226-5 Restrictions on Subcontracting Outside Disaster or Emergency Area. As prescribed in 26.206(c), insert the following clause: Restrictions on Subcontracting...

  4. 75 FR 32723 - Revision of Department of Homeland Security Acquisition Regulation; Limitations on Subcontracting...

    Science.gov (United States)

    2010-06-09

    ... Acquisition Regulation; Limitations on Subcontracting in Emergency Acquisitions (HSAR Case 2009-005) AGENCY... on subcontracting for cost-reimbursement type contracts above the simplified acquisition threshold... authority to determine whether or not the subcontracting requirements are not feasible or practicable rests...

  5. 48 CFR 252.219-7004 - Small business subcontracting plan (test program).

    Science.gov (United States)

    2010-10-01

    ... AND CONTRACT CLAUSES Text of Provisions And Clauses 252.219-7004 Small business subcontracting plan... contract or subcontract. (b) The Offeror's comprehensive small business subcontracting plan and its... “Utilization of Small Business Concerns,” or (2) an approved plan required by this clause, shall be a material...

  6. 48 CFR 2452.219-70 - Small business subcontracting plan compliance.

    Science.gov (United States)

    2010-10-01

    ... of Provisions and Clauses 2452.219-70 Small business subcontracting plan compliance. As prescribed in 2419.708(d), insert the following provision: Small Business Subcontracting Plan Compliance (FEB 2006... the clause at FAR 52.219-9, Small Business Subcontracting Plan. (c) The government will consider...

  7. 48 CFR 252.219-7003 - Small business subcontracting plan (DoD contracts).

    Science.gov (United States)

    2010-10-01

    ... AND CONTRACT CLAUSES Text of Provisions And Clauses 252.219-7003 Small business subcontracting plan...-9, Small Business Subcontracting Plan, clause of this contract. (a) Definitions. Historically black... division-wide commercial items subcontracting plans, the term small disadvantaged business, when used in...

  8. 48 CFR 852.219-9 - VA Small business subcontracting plan minimum requirements.

    Science.gov (United States)

    2010-10-01

    ... Provisions and Clauses 852.219-9 VA Small business subcontracting plan minimum requirements. As prescribed in subpart 819.709, insert the following clause: VA Small Business Subcontracting Plan Minimum Requirements... plan, the minimum goals for award of subcontracts to service-disabled veteran-owned small business...

  9. Subcontracting in international B-to-B market

    OpenAIRE

    Ma, Jing

    2011-01-01

    The purpose of this thesis is the subcontracting and its internationalization, description of the process to find subcontractor from China. The whole thesis will be divided into five chapters; the studying area focuses on the B to B market, and elaborates the international subcontracting in B to B market, its benefits, roles, selection and process. The first part will from general conceptions of B-to-B, it will include relationship of traditional B-to-B and modern B-to-B development,...

  10. Forecast of contracting and subcontracting opportunities: Fiscal year 1998

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-01-01

    This report describes procurement procedures and opportunities for small businesses with the Department of Energy (DOE). It describes both prime and subcontracting opportunities of $100,000 and above which are being set aside for 8(a) and other small business concerns. The report contains sections on: SIC codes; procurement opportunities with headquarters offices; procurement opportunities with field offices; subcontracting opportunities with major contractors; 8(a) contracts expiring in FY 1998; other opportunities to do business with DOE; management and operating contractors--expiration dates; Office of Small and Disadvantaged Business Utilization (OSDBU) staff directory; and small business survey. This document will be updated quarterly on the home page.

  11. 13 CFR 126.102 - What is the effect of the HUBZone program on the section 8(d) subcontracting program?

    Science.gov (United States)

    2010-01-01

    ... program on the section 8(d) subcontracting program? 126.102 Section 126.102 Business Credit and Assistance... effect of the HUBZone program on the section 8(d) subcontracting program? The HUBZone Act of 1997 amended the section 8(d) subcontracting program to include qualified HUBZone SBCs in the formal subcontracting...

  12. 13 CFR 121.411 - What are the size procedures for SBA's Section 8(d) Subcontracting Program?

    Science.gov (United States)

    2010-01-01

    ... SBA's Section 8(d) Subcontracting Program? 121.411 Section 121.411 Business Credit and Assistance...'s Section 8(d) Subcontracting Program? (a) Prime contractors may rely on the information contained... subcontracting or proposing to subcontract under section 8(d) of the Small Business Act may be protested by the...

  13. The NASA Plan: To award eight percent of prime and subcontracts to socially and economically disadvantaged businesses

    Science.gov (United States)

    1990-01-01

    It is NASA's intent to provide small disadvantaged businesses, including women-owned, historically black colleges and universities and minority education institutions the maximum practicable opportunity to receive a fair proportion of NASA prime and subcontracted awards. Annually, NASA will establish socioeconomic procurement goals including small disadvantaged business goals, with a target of reaching the eight percent level by the end of FY 1994. The NASA Associate Administrators, who are responsible for the programs at the various NASA Centers, will be held accountable for full implementation of the socioeconomic procurement plans. Various aspects of this plan, including its history, are discussed.

  14. Semiconductor statistics

    CERN Document Server

    Blakemore, J S

    1962-01-01

    Semiconductor Statistics presents statistics aimed at complementing existing books on the relationships between carrier densities and transport effects. The book is divided into two parts. Part I provides introductory material on the electron theory of solids, and then discusses carrier statistics for semiconductors in thermal equilibrium. Of course a solid cannot be in true thermodynamic equilibrium if any electrical current is passed; but when currents are reasonably small the distribution function is but little perturbed, and the carrier distribution for such a """"quasi-equilibrium"""" co

  15. Semiconductor electrochemistry

    CERN Document Server

    Memming, Rüdiger

    2015-01-01

    Providing both an introduction and an up-to-date survey of the entire field, this text captivates the reader with its clear style and inspiring, yet solid presentation. The significantly expanded second edition of this milestone work is supplemented by a completely new chapter on the hot topic of nanoparticles and includes the latest insights into the deposition of dye layers on semiconductor electrodes. In his monograph, the acknowledged expert Professor Memming primarily addresses physical and electrochemists, but materials scientists, physicists, and engineers dealing with semiconductor technology and its applications will also benefit greatly from the contents.

  16. Oxide semiconductors

    CERN Document Server

    Svensson, Bengt G; Jagadish, Chennupati

    2013-01-01

    Semiconductors and Semimetals has distinguished itself through the careful selection of well-known authors, editors, and contributors. Originally widely known as the ""Willardson and Beer"" Series, it has succeeded in publishing numerous landmark volumes and chapters. The series publishes timely, highly relevant volumes intended for long-term impact and reflecting the truly interdisciplinary nature of the field. The volumes in Semiconductors and Semimetals have been and will continue to be of great interest to physicists, chemists, materials scientists, and device engineers in academia, scient

  17. Investigation of the basic physics of high efficiency semiconductor hot carrier solar cell. Annual status report, 31 May 1994-30 May 1995

    Energy Technology Data Exchange (ETDEWEB)

    Alfano, R.R.; Wang, W.B.; Mohaidat, J.M.; Cavicchia, M.A.; Raisky, O.Y.

    1995-05-01

    The main purpose of this research program is to investigate potential semiconductor materials and their multi-band-gap MQW (multiple quantum wells) structures for high efficiency solar cells for aerospace and commercial applications. The absorption and PL (photoluminescence) spectra, the carrier dynamics, and band structures have been investigated for semiconductors of InP, GaP, GaInP, and InGaAsP/InP MQW structures, and for semiconductors of GaAs and AlGaAs by previous measurements. The barrier potential design criteria for achieving maximum energy conversion efficiency, and the resonant tunneling time as a function of barrier width in high efficiency MQW solar cell structures have also been investigated in the first two years. Based on previous carrier dynamics measurements and the time-dependent short circuit current density calculations, an InAs/InGaAs - InGaAs/GaAs - GaAs/AlGaAs MQW solar cell structure with 15 bandgaps has been designed. The absorption and PL spectra in InGaAsP/InP bulk and MQW structures were measured at room temperature and 77 K with different pump wavelength and intensity, to search for resonant states that may affect the solar cell activities. Time-resolved IR absorption for InGaAsP/InP bulk and MQW structures has been measured by femtosecond visible-pump and IR-probe absorption spectroscopy. This, with the absorption and PL measurements, will be helpful to understand the basic physics and device performance in multi-bandgap InAs/InGaAs - InGaAs/InP - InP/InGaP MQW solar cells. In particular, the lifetime of the photoexcited hot electrons is an important parameter for the device operation of InGaAsP/InP MQW solar cells working in the resonant tunneling conditions. Lastly, time evolution of the hot electron relaxation in GaAs has been measured in the temperature range of 4 K through 288 K using femtosecond pump-IR-probe absorption technique.

  18. Formal sector subcontracting and informal sector employment in Indian manufacturing

    NARCIS (Netherlands)

    Moreno-Monroy, A.I.; Pieters, J.; Erumban, A.A.

    2014-01-01

    Using nationally representative survey dta of Indian manufacturing enterprises spanning the period 1995-2006, we analyze the link between formal sector subcontracting and informal sector employment. A novelty in our analysis is that this relationship is allowed to differ between modern and

  19. 48 CFR 52.222-11 - Subcontracts (Labor Standards).

    Science.gov (United States)

    2010-10-01

    ...: Subcontracts (Labor Standards) (JUL 2005) (a) Definition. Construction, alteration or repair, as used in this clause, means all types of work done by laborers and mechanics employed by the construction Contractor or construction subcontractor on a particular building or work at the site thereof, including without limitation...

  20. 48 CFR 852.236-80 - Subcontracts and work coordination.

    Science.gov (United States)

    2010-10-01

    ... well as the location and elevation of utility lines, including, but not limited to, conveyor systems... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Subcontracts and work coordination. 852.236-80 Section 852.236-80 Federal Acquisition Regulations System DEPARTMENT OF VETERANS...

  1. Ultrafast spectroscopy of semiconductors and semiconductor nanostructures

    CERN Document Server

    Shah, Jagdeep

    1996-01-01

    Ultrafast Spectroscopy of Semiconductors and Semiconductor Nanostructures Ultrafast spectroscopy of semiconductors is currently one of the most exciting areas of research in condensed-matter physics Remarkable recent progress in the generation of tunable femtosecond pulses has allowed direct investigation of the most fundamental dynamical processes in semiconductors This monograph presents some of the most striking recent advances in the field of ultrafast spectroscopy of semiconductors and their nanostructures After a brief overview of the basic concepts and of the recent advances in the techniques of ultrashort pulse generation and ultrafast spectroscopy, it discusses the physics of relaxation, tunneling and transport dynamics in semiconductors and semiconductor nanostructures following excitation by femtosecond laser pulses

  2. Transferring the Cost of Wage Rigidity to Subcontracting Firms: The Case of Korea

    Directory of Open Access Journals (Sweden)

    Kwangho Woo

    2016-08-01

    Full Text Available We select a Korean case with ample subcontracting practices and a rigid wage system. Workplaces with subcontract transactions would have reason to impute the additional wage incremental costs associated with the seniority-based wage system (Hobong in Korea to subcontractors. Our empirical results identify the cost-transferring mechanism under which the cost of wage rigidity for contractors is transferred to subcontracting firms and aggravates the wage inequality among workers in contracting and subcontracting firms. We analyze the industrial difference in the intensity of this transferring mechanism and probe policy directions considering the improvement of both the subcontracting structure and pay system simultaneously. For the sustainability of firms, they need to reform a seniority-based wage system, an incentive-based wage system or a job-based wage system and the exploited subcontracting structure for creating share value.

  3. Magnetic semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Bihler, Christoph

    2009-04-15

    In this thesis we investigated in detail the properties of Ga{sub 1-x}Mn{sub x}As, Ga{sub 1-x}Mn{sub x}P, and Ga{sub 1-x}Mn{sub x}N dilute magnetic semiconductor thin films with a focus on the magnetic anisotropy and the changes of their properties upon hydrogenation. We applied two complementary spectroscopic techniques to address the position of H in magnetic semiconductors: (i) Electron paramagnetic resonance, which provides direct information on the symmetry of the crystal field of the Mn{sup 2+} atoms and (ii) x-ray absorption fine structure analysis which allows to probe the local crystallographic neighborhood of the absorbing Mn atom via analysing the fine structure at the Mn K absorption edge. Finally, we discussed the obstacles that have to be overcome to achieve Curie temperatures above the current maximum in Ga{sub 1-x}Mn{sub x}As of 185 K. Here, we outlined in detail the generic problem of the formation of precipitates at the example of Ge:MN. (orig.)

  4. Power semiconductors

    CERN Document Server

    Kubát, M

    1984-01-01

    The book contains a summary of our knowledge of power semiconductor structures. It presents first a short historic introduction (Chap. I) as well as a brief selection of facts from solid state physics, in particular those related to power semiconductors (Chap. 2). The book deals with diode structures in Chap. 3. In addition to fundamental facts in pn-junction theory, the book covers mainly the important processes of power structures. It describes the emitter efficiency and function of microleaks (shunts). the p +p and n + n junctions, and in particular the recent theory of the pin, pvn and p1tn junctions, whose role appears to be decisive for the forward mode not only of diode structures but also of more complex ones. For power diode structures the reverse mode is the decisive factor in pn-junction breakdown theory. The presentation given here uses engineering features (the multiplication factor M and the experimentally detected laws for the volume and surface of crystals), which condenses the presentation an...

  5. Semiconductor Laser Measurements Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Semiconductor Laser Measurements Laboratory is equipped to investigate and characterize the lasing properties of semiconductor diode lasers. Lasing features such...

  6. 13 CFR 121.410 - What are the size standards for SBA's Section 8(d) Subcontracting Program?

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false What are the size standards for SBA's Section 8(d) Subcontracting Program? 121.410 Section 121.410 Business Credit and Assistance...'s Section 8(d) Subcontracting Program? For subcontracting purposes pursuant to sections 8(d) of the...

  7. 48 CFR 1519.705-70 - Synopsis of contracts containing Pub. L. 95-507 subcontracting plans and goals.

    Science.gov (United States)

    2010-10-01

    ... containing Pub. L. 95-507 subcontracting plans and goals. 1519.705-70 Section 1519.705-70 Federal Acquisition... Subcontracting With Small Business and Small Disadvantaged Business Concerns 1519.705-70 Synopsis of contracts containing Pub. L. 95-507 subcontracting plans and goals. The synopsis of contract award, where applicable...

  8. 48 CFR 952.226-70 - Subcontracting goals under section 3021(a) of the Energy Policy Act of 1992.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Subcontracting goals under... Provisions and Clauses 952.226-70 Subcontracting goals under section 3021(a) of the Energy Policy Act of 1992. As prescribed in 926.7007(a), insert the following provision: Subcontracting Goals Under Section 3021...

  9. 48 CFR 53.301-294 - Subcontracting Report for Individual Contracts.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Subcontracting Report for Individual Contracts. 53.301-294 Section 53.301-294 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION (CONTINUED) CLAUSES AND FORMS FORMS Illustrations of Forms 53.301-294 Subcontracting...

  10. 48 CFR 2453.227-70 - Form HUD-770, Report of Inventions and Subcontracts.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Form HUD-770, Report of Inventions and Subcontracts. 2453.227-70 Section 2453.227-70 Federal Acquisition Regulations System... HUD-770, Report of Inventions and Subcontracts. As prescribed in 2427.305-2, form HUD-770 shall be...

  11. Tri-State Synfuels Project Review: Volume 9A. Subcontract information. [Proposed Henderson, Kentucky coal to gasoline plant; water supply and civil engineering subcontracts

    Energy Technology Data Exchange (ETDEWEB)

    1982-06-01

    Volume 9A considers subcontract work done at the site involving hydrogeological studies with respect to water supply and geotechnical work with respect to the building foundations necessary based on boreholes drilled and the lithology of the area. (LTN)

  12. Influence of subcontracting constraints on the performance of manufacturing industries in Nigeria

    Directory of Open Access Journals (Sweden)

    Victor Chukwunweike Nwokocha

    2015-01-01

    Full Text Available In this work, an attempt has been made to show the influence of subcontracting constraints on firm performance in Nigeria. The study in line with the literature identified a number of constraints hindering an effective subcontracting arrangement in the study area. While the constraints were found not to have affected the use of subcontracting in the country, low capital intensity, disclosure of commercial secrets, poor services and interest conflict were found to have restricted subcontracting arrangements in the study area to sharing of equipment and short-term contracts. These constraints however were found not have affected the performance of manufacturing industries in the study area. This paper keeping in mind the findings of this study suggested that manufacturing industries in Nigeria should invest more in machineries and tools so as to increase subcontracting co-operations among industries.

  13. Forecast of contracting and subcontracting opportunities. Fiscal year 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-02-01

    This forecast of prime and subcontracting opportunities with the U.S. Department of Energy and its MAO contractors and environmental restoration and waste management contractors, is the Department`s best estimate of small, small disadvantaged and women-owned small business procurement opportunities for fiscal year 1996. The information contained in the forecast is published in accordance with Public Law 100-656. It is not an invitation for bids, a request for proposals, or a commitment by DOE to purchase products or services. Each procurement opportunity is based on the best information available at the time of publication and may be revised or cancelled.

  14. Construction Tender Subcontract Selection using Case-based Reasoning

    Directory of Open Access Journals (Sweden)

    Due Luu

    2012-11-01

    Full Text Available Obtaining competitive quotations from suitably qualified subcontractors at tender tim n significantly increase the chance of w1nmng a construction project. Amidst an increasingly growing trend to subcontracting in Australia, selecting appropriate subcontractors for a construction project can be a daunting task requiring the analysis of complex and dynamic criteria such as past performance, suitable experience, track record of competitive pricing, financial stability and so on. Subcontractor selection is plagued with uncertainty and vagueness and these conditions are difficul_t o represent in generalised sets of rules. DeciSIOns pertaining to the selection of subcontr:act?s tender time are usually based on the mtu1t1onand past experience of construction estimators. Case-based reasoning (CBR may be an appropriate method of addressing the chal_lenges of selecting subcontractors because CBR 1s able to harness the experiential knowledge of practitioners. This paper reviews the practicality and suitability of a CBR approach for subcontractor tender selection through the development of a prototype CBR procurement advisory system. In this system, subcontractor selection cases are represented by a set of attributes elicited from experienced construction estimators. The results indicate that CBR can enhance the appropriateness of the selection of subcontractors for construction projects.

  15. Fundamentals of semiconductor devices

    CERN Document Server

    Lindmayer, Joseph

    1965-01-01

    Semiconductor properties ; semiconductor junctions or diodes ; transistor fundamentals ; inhomogeneous impurity distributions, drift or graded-base transistors ; high-frequency properties of transistors ; band structure of semiconductors ; high current densities and mechanisms of carrier transport ; transistor transient response and recombination processes ; surfaces, field-effect transistors, and composite junctions ; additional semiconductor characteristics ; additional semiconductor devices and microcircuits ; more metal, insulator, and semiconductor combinations for devices ; four-pole parameters and configuration rotation ; four-poles of combined networks and devices ; equivalent circuits ; the error function and its properties ; Fermi-Dirac statistics ; useful physical constants.

  16. Subcontracting in the Italian industry. Labour Division, Firm Growth and the North-South Divide

    OpenAIRE

    Giunta, Anna; Nifo, Annamaria; Scalera, Domenico

    2009-01-01

    The aim of this paper is to investigate the impact of subcontracting on Italian manufacturing firms’ growth in the second half of the 1990s. By making use of a 5000 firms database we specifically test: a) whether and how subcontracting may affect the growth dynamics of firms; b) whether growth could be due to stronger incentives to innovate for subcontracting firms keen to move up the value chain, which would be consistent with the predictions of the Global Value Chain approach; and c) the jo...

  17. Reserve current analysis in semiconductor insulator semiconductor ...

    African Journals Online (AJOL)

    Reserve current analysis in semiconductor insulator semiconductor (SIS) solar cells. H Yakubu, PK Mensah. Abstract. No Abstract. Journal of the Ghana Association Vol. 2 (3) 1999: pp. 1-4. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

  18. Forecast of Contracting and Subcontracting Opportunities, Fiscal year 1995

    Energy Technology Data Exchange (ETDEWEB)

    1995-02-01

    Welcome to the US Department of Energy`s Forecast of Contracting and Subcontracting Opportunities. This forecast, which is published pursuant to Public Low 100--656, ``Business Opportunity Development Reform Act of 1988,`` is intended to inform small business concerns, including those owned and controlled by socially and economically disadvantaged individuals, and women-owned small business concerns, of the anticipated fiscal year 1995 contracting and subcontracting opportunities with the Department of Energy and its management and operating contractors and environmental restoration and waste management contractors. This document will provide the small business contractor with advance notice of the Department`s procurement plans as they pertain to small, small disadvantaged and women-owned small business concerns.Opportunities contained in the forecast support the mission of the Department, to serve as advocate for the notion`s energy production, regulation, demonstration, conservation, reserve maintenance, nuclear weapons and defense research, development and testing, when it is a national priority. The Department`s responsibilities include long-term, high-risk research and development of energy technology, the marketing of Federal power, and maintenance of a central energy data collection and analysis program. A key mission for the Department is to identify and reduce risks, as well as manage waste at more than 100 sites in 34 states and territories, where nuclear energy or weapons research and production resulted in radioactive, hazardous, and mixed waste contamination. Each fiscal year, the Department establishes contracting goals to increase contracts to small business concerns and meet our mission objectives.

  19. Handbook of spintronic semiconductors

    CERN Document Server

    Chen, Weimin

    2010-01-01

    Offers a review of the field of spintronic semiconductors. This book covers a range of topics, including growth and basic physical properties of diluted magnetic semiconductors based on II-VI, III-V and IV semiconductors, developments in theory and experimental techniques and potential device applications.

  20. Gendering Industrial Subcontracting Work: A Qualitative Study of Garment Ateliers in Istanbul

    National Research Council Canada - National Science Library

    Saniye Dedeoglu

    2011-01-01

    .... Supported by flexible production and subcontracting relations, family-owned garment ateliers have become the prominent location of production and have opened up the doors of the global markets...

  1. Subcontracting in the Italian industry. Labour Division, Firms’ Growth and North-South Divide

    OpenAIRE

    Giunta, Anna; Nifo, Annamaria; Scalera, Domenico

    2009-01-01

    By making use of a 4000 firms database, this paper analyzes the dynamics of division of labour among Italian manufacturing firms during the '90s, and seeks to assess the impact that subcontracting has on manufacturing firms' growth. In particular, we investigate the relationship between labour division and firms' growth with three specific objectives: a) to understand whether and how subcontracting may have affected firms' growth dynamics; b) to test if larger growth could be due to stronger ...

  2. Integration versus subcontracting: The case of the French automotive industry (1945-1970)

    OpenAIRE

    Pezet, Anne; Nogatchewsky, Gwenaëlle; Fabre, Karine

    2008-01-01

    Today’s car manufacturers resort widely to subcontracting, but the origins of this practice are not recent. From the beginning of the twentieth century, the car manufacturer Louis Renault committed the production of some components to external suppliers, although the company is often presented as a comprehensive model of vertical integration. This article aims to describe the evolution of subcontracting within the Renault firm from 1945 to the 1970s. This family business company constitutes a...

  3. Small Business: Action Needed to Determine Whether DOD’s Comprehensive Subcontracting Plan Test Program Should Be Made Permanent

    Science.gov (United States)

    2015-11-01

    SMALL BUSINESS Action Needed to Determine Whether DOD’s Comprehensive Subcontracting Plan Test Program Should Be... Subcontracting Plan Test Program Should Be Made Permanent 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT...committees November 2015 SMALL BUSINESS Action Needed to Determine Whether DOD’s Comprehensive Subcontracting Plan Test Program Should Be Made

  4. Semiconductor Physical Electronics

    CERN Document Server

    Li, Sheng

    2006-01-01

    Semiconductor Physical Electronics, Second Edition, provides comprehensive coverage of fundamental semiconductor physics that is essential to an understanding of the physical and operational principles of a wide variety of semiconductor electronic and optoelectronic devices. This text presents a unified and balanced treatment of the physics, characterization, and applications of semiconductor materials and devices for physicists and material scientists who need further exposure to semiconductor and photonic devices, and for device engineers who need additional background on the underlying physical principles. This updated and revised second edition reflects advances in semicondutor technologies over the past decade, including many new semiconductor devices that have emerged and entered into the marketplace. It is suitable for graduate students in electrical engineering, materials science, physics, and chemical engineering, and as a general reference for processing and device engineers working in the semicondi...

  5. Semiconductor devices physics and technology

    CERN Document Server

    Sze, Simon

    2012-01-01

    Semiconductor Devices: Physics and Technology, Third Edition is an introduction to the physical principles of modern semiconductor devices and their advanced fabrication technology. It begins with a brief historical review of major devices and key technologies and is then divided into three sections: semiconductor material properties, physics of semiconductor devices and processing technology to fabricate these semiconductor devices.

  6. Semiconductor Electrical Measurements Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Semiconductor Electrical Measurements Laboratory is a research laboratory which complements the Optical Measurements Laboratory. The laboratory provides for Hall...

  7. Basic semiconductor physics

    CERN Document Server

    Hamaguchi, Chihiro

    2001-01-01

    This book presents a detailed description of the basic physics of semiconductors. All the important equations describing the properties of these materials are derived without the help of other textbooks. The reader is assumed to have only a basic command of mathematics and some elementary semiconductor physics. The text covers a wide range of important semiconductor phenomena, from the simple to the advanced. Examples include recent progress in semiconductor quantum structures such as two-dimensional electron-gas systems, ballistic transport, the quantum Hall effect, the Landauer formula, the Coulomb blockade and the single-electron transistor.

  8. Semiconductor radiation detectors. Device physics

    Energy Technology Data Exchange (ETDEWEB)

    Lutz, G. [Max-Planck-Institut fuer Physik, Muenchen (Germany)]|[Max-Planck-Institut fuer Extraterrestrische Physik, Garching (Germany). Semiconductor Lab.

    1999-07-01

    The following topics were dealt with: semiconductor radiation detectors, basic semiconductor structures, semiconductors, energy measurement, radiation-level measurement, position measurement, electronics of the readout function, detectors with intrinsic amplification, detector technology, device stability, radiation hardness and device simulation.

  9. Two cases of methyl alcohol intoxication by sub-chronic inhalation and dermal exposure during aluminum CNC cutting in a small-sized subcontracted factory.

    Science.gov (United States)

    Ryu, Jia; Lim, Key Hwan; Ryu, Dong-Ryeol; Lee, Hyang Woon; Yun, Ji Young; Kim, Seoung-Wook; Kim, Ji-Hoon; Jung-Choi, Kyunghee; Kim, Hyunjoo

    2016-01-01

    Methyl alcohol poisoning has been mainly reported in community. Two cases of methyl alcohol poisoning occurred in a small-sized subcontracted factory which manufactured smartphone parts in Korea. One young female patient presented with dyspnea and visual disturbance. Another young male patient presented with visual disturbance and myalgia. They treated with sodium bicarbonate infusion and hemodialysis for metabolic acidosis. In addition, he received ethyl alcohol per oral treatment. Her and his urinary methyl alcohol concentration was detected as 7.632 mg/L, 46.8 mg/L, respectively, although they were treated hemodialysis. Results of the working environment measurement showed that the concentration of methyl alcohol (1030.1-2220.5 ppm) in the air exceeded the time weighted average (200 ppm). They were diagnosed with optic neuropathy due to methyl alcohol poisoning and still have visual impairment. Workers who hired as dispatched employees in a small-sized subcontracted factory were exposed to high concentrations of methyl alcohol. The workplace had poor ventilation system. In addition, workers did not wear proper personal protect equipment. Working environment measurement and annual chekups for workers were not performed. They were in a blind spot to occupational safety and health. More attention is needed to protect vulnerable workers' health.

  10. 48 CFR 252.209-7004 - Subcontracting with firms that are owned or controlled by the government of a terrorist country.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Subcontracting with firms....209-7004 Subcontracting with firms that are owned or controlled by the government of a terrorist country. As prescribed in 209.409, use the following clause: Subcontracting with Firms that are Owned or...

  11. A survey of the literature on challenges to safety posed by outsourcing or subcontracting of critical tasks

    DEFF Research Database (Denmark)

    Thommesen, Jacob; Andersen, Henning Boje; Øien, Knut

    The purpose of this document is to report on a review of the literature on the relation between safety and outsourcing or subcontracting. The review seeks to identify the problems and solutions that have been identified and described in the literature concerning outsourcing and subcontracting...

  12. 48 CFR 970.1907 - Subcontracting with Small Business, Small Disadvantaged Business and Woman-Owned Small Business...

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Subcontracting with Small Business, Small Disadvantaged Business and Woman-Owned Small Business Concerns. 970.1907 Section 970.1907....1907 Subcontracting with Small Business, Small Disadvantaged Business and Woman-Owned Small Business...

  13. 48 CFR 215.370 - Evaluation factor for employing or subcontracting with members of the Selected Reserve.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Evaluation factor for employing or subcontracting with members of the Selected Reserve. 215.370 Section 215.370 Federal... employing or subcontracting with members of the Selected Reserve. ...

  14. 24 CFR 964.320 - HUD Policy on training, employment, contracting and subcontracting of public housing residents.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false HUD Policy on training, employment, contracting and subcontracting of public housing residents. 964.320 Section 964.320 Housing and Urban... training, employment, contracting and subcontracting of public housing residents. In accordance with...

  15. Semiconductors data handbook

    CERN Document Server

    Madelung, Otfried

    2004-01-01

    This volume Semiconductors: Data Handbook contains frequently used data from the corresponding larger Landolt-Börnstein handbooks in a low price book for the individual scientist working in the laboratory. The Handbook contain important information about a large number of semiconductors

  16. High energy semiconductor switch

    Science.gov (United States)

    Risberg, R. L.

    1989-02-01

    The objective was a controller for electric motors. By operating standard Nema B induction motors at variable speed a great deal of energy is saved. This is especially true in pumping and air conditioning applications. To allow wider use of variable speed AC drives, and to provide improved performance, a better semiconductor switch was sought. This was termed the High Energy Semiconductor Switch.

  17. Semiconductor radiation detection systems

    CERN Document Server

    2010-01-01

    Covers research in semiconductor detector and integrated circuit design in the context of medical imaging using ionizing radiation. This book explores other applications of semiconductor radiation detection systems in security applications such as luggage scanning, dirty bomb detection and border control.

  18. Semiconductor Research Experimental Techniques

    CERN Document Server

    Balkan, Naci

    2012-01-01

    The book describes the fundamentals, latest developments and use of key experimental techniques for semiconductor research. It explains the application potential of various analytical methods and discusses the opportunities to apply particular analytical techniques to study novel semiconductor compounds, such as dilute nitride alloys. The emphasis is on the technique rather than on the particular system studied.

  19. Spin physics in semiconductors

    CERN Document Server

    Dyakonov, Mikhail I

    2008-01-01

    This book describes beautiful optical and transport phenomena related to the electron and nuclear spins in semiconductors with emphasis on a clear presentation of the physics involved. Recent results on quantum wells and quantum dots are reviewed. The book is intended for students and researchers in the fields of semiconductor physics and nanoelectronics.

  20. Compound Semiconductor Radiation Detectors

    CERN Document Server

    Owens, Alan

    2012-01-01

    Although elemental semiconductors such as silicon and germanium are standard for energy dispersive spectroscopy in the laboratory, their use for an increasing range of applications is becoming marginalized by their physical limitations, namely the need for ancillary cooling, their modest stopping powers, and radiation intolerance. Compound semiconductors, on the other hand, encompass such a wide range of physical and electronic properties that they have become viable competitors in a number of applications. Compound Semiconductor Radiation Detectors is a consolidated source of information on all aspects of the use of compound semiconductors for radiation detection and measurement. Serious Competitors to Germanium and Silicon Radiation Detectors Wide-gap compound semiconductors offer the ability to operate in a range of hostile thermal and radiation environments while still maintaining sub-keV spectral resolution at X-ray wavelengths. Narrow-gap materials offer the potential of exceeding the spectral resolutio...

  1. R&D cooperation versus R&D subcontracting: empirical evidence from French survey data.

    OpenAIRE

    Estelle Dhont-Peltrault; Etienne Pfister

    2007-01-01

    This paper uses a survey of French firms active in R&D to identify the determinants of R&D outsourcing and of the ensuing trade-off between R&D subcontracting and R&D cooperation. Internal R&D expenditures increase both the probability of outsourcing and the number of R&D partners. Investment in fundamental R&D, group belonging, and the sector’s high R&D intensity positively influences the probability of R&D outsourcing but have less impact on the number of partners. R&D subcontracting is mor...

  2. Physics of semiconductor lasers

    CERN Document Server

    Mroziewicz, B; Nakwaski, W

    2013-01-01

    Written for readers who have some background in solid state physics but do not necessarily possess any knowledge of semiconductor lasers, this book provides a comprehensive and concise account of fundamental semiconductor laser physics, technology and properties. The principles of operation of these lasers are therefore discussed in detail with the interrelations between their design and optical, electrical and thermal properties. The relative merits of a large number of laser structures and their parameters are described to acquaint the reader with the various aspects of the semiconductor l

  3. Defects in semiconductors

    CERN Document Server

    Romano, Lucia; Jagadish, Chennupati

    2015-01-01

    This volume, number 91 in the Semiconductor and Semimetals series, focuses on defects in semiconductors. Defects in semiconductors help to explain several phenomena, from diffusion to getter, and to draw theories on materials' behavior in response to electrical or mechanical fields. The volume includes chapters focusing specifically on electron and proton irradiation of silicon, point defects in zinc oxide and gallium nitride, ion implantation defects and shallow junctions in silicon and germanium, and much more. It will help support students and scientists in their experimental and theoret

  4. Semiconductors bonds and bands

    CERN Document Server

    Ferry, David K

    2013-01-01

    As we settle into this second decade of the twenty-first century, it is evident that the advances in micro-electronics have truly revolutionized our day-to-day lifestyle. The technology is built upon semiconductors, materials in which the band gap has been engineered for special values suitable to the particular application. This book, written specifically for a one semester course for graduate students, provides a thorough understanding of the key solid state physics of semiconductors. It describes how quantum mechanics gives semiconductors unique properties that enabled the micro-electronics revolution, and sustain the ever-growing importance of this revolution.

  5. Spin physics in semiconductors

    CERN Document Server

    2017-01-01

    This book offers an extensive introduction to the extremely rich and intriguing field of spin-related phenomena in semiconductors. In this second edition, all chapters have been updated to include the latest experimental and theoretical research. Furthermore, it covers the entire field: bulk semiconductors, two-dimensional semiconductor structures, quantum dots, optical and electric effects, spin-related effects, electron-nuclei spin interactions, Spin Hall effect, spin torques, etc. Thanks to its self-contained style, the book is ideally suited for graduate students and researchers new to the field.

  6. Compact semiconductor lasers

    CERN Document Server

    Yu, Siyuan; Lourtioz, Jean-Michel

    2014-01-01

    This book brings together in a single volume a unique contribution by the top experts around the world in the field of compact semiconductor lasers to provide a comprehensive description and analysis of the current status as well as future directions in the field of micro- and nano-scale semiconductor lasers. It is organized according to the various forms of micro- or nano-laser cavity configurations with each chapter discussing key technical issues, including semiconductor carrier recombination processes and optical gain dynamics, photonic confinement behavior and output coupling mechanisms, carrier transport considerations relevant to the injection process, and emission mode control. Required reading for those working in and researching the area of semiconductors lasers and micro-electronics.

  7. Defects in semiconductor nanostructures

    Science.gov (United States)

    Singh, Vijay A.; Harbola, Manoj K.; Pathak, Praveen

    2008-02-01

    Impurities play a pivotal role in semiconductors. One part in a million of phosphorous in silicon alters the conductivity of the latter by several orders of magnitude. Indeed, the information age is possible only because of the unique role of shallow impurities in semiconductors. Although work in semiconductor nanostructures (SN) has been in progress for the past two decades, the role of impurities in them has been only sketchily studied. We outline theoretical approaches to the electronic structure of shallow impurities in SN and discuss their limitations. We find that shallow levels undergo a SHADES (SHAllow-DEep-Shallow) transition as the SN size is decreased. This occurs because of the combined effect of quantum confinement and reduced dielectric constant in SN. Level splitting is pronounced and this can perhaps be probed by ESR and ENDOR techniques. Finally, we suggest that a perusal of literature on (semiconductor) cluster calculations carried out 30 years ago would be useful.

  8. Physics of semiconductor devices

    CERN Document Server

    Rudan, Massimo

    2015-01-01

    This book describes the basic physics of semiconductors, including the hierarchy of transport models, and connects the theory with the functioning of actual semiconductor devices.  Details are worked out carefully and derived from the basic physics, while keeping the internal coherence of the concepts and explaining various levels of approximation. Examples are based on silicon due to its industrial importance. Several chapters are included that provide the reader with the quantum-mechanical concepts necessary for understanding the transport properties of crystals. The behavior of crystals incorporating a position-dependent impurity distribution is described, and the different hierarchical transport models for semiconductor devices are derived (from the Boltzmann transport equation to the hydrodynamic and drift-diffusion models). The transport models are then applied to a detailed description of the main semiconductor-device architectures (bipolar, MOS). The final chapters are devoted to the description of s...

  9. Biggest semiconductor installed

    CERN Multimedia

    2008-01-01

    Scientists and technicians at the European Laboratory for Particle Physics, commonly known by its French acronym CERN (Centre Europen pour la Recherche Nuclaire), have completed the installation of the largest semiconductor silicon detector.

  10. Electrowetting on a semiconductor

    OpenAIRE

    Arscott, Steve; Gaudet, Matthieu

    2012-01-01

    We report electrowetting on a semiconductor using of a mercury droplet resting on a silicon surface. The effect is demonstrated using commercial n-type and p-type single-crystal (100) silicon wafers of different doping levels. The electrowetting is reversible - the voltage-dependent wetting contact angle variation of the mercury droplet is observed to depend on both the underlying semiconductor doping density and type. The electrowetting behaviour is explained by the voltage-dependent modulat...

  11. Radiation effects in semiconductors

    CERN Document Server

    2011-01-01

    There is a need to understand and combat potential radiation damage problems in semiconductor devices and circuits. Written by international experts, this book explains the effects of radiation on semiconductor devices, radiation detectors, and electronic devices and components. These contributors explore emerging applications, detector technologies, circuit design techniques, new materials, and innovative system approaches. The text focuses on how the technology is being used rather than the mathematical foundations behind it. It covers CMOS radiation-tolerant circuit implementations, CMOS pr

  12. 48 CFR 1852.219-82 - Limitation on subcontracting-STTR program.

    Science.gov (United States)

    2010-10-01

    ... subcontracting-STTR program. 1852.219-82 Section 1852.219-82 Federal Acquisition Regulations System NATIONAL... Provisions and Clauses 1852.219-82 Limitation on subcontracting—STTR program. As prescribed in 1819.7302(c), insert the following clause: Limitation on Subcontracting—STTR Program (OCT 2006) The Contractor shall...

  13. 48 CFR 1852.219-81 - Limitation on subcontracting-SBIR Phase II program.

    Science.gov (United States)

    2010-10-01

    ... subcontracting-SBIR Phase II program. 1852.219-81 Section 1852.219-81 Federal Acquisition Regulations System... CLAUSES Texts of Provisions and Clauses 1852.219-81 Limitation on subcontracting—SBIR Phase II program. As prescribed in 1819.7302(b), insert the following clause: Limitation on Subcontracting—SBIR Phase II Program...

  14. 48 CFR 1852.219-80 - Limitation on subcontracting-SBIR Phase I program.

    Science.gov (United States)

    2010-10-01

    ... subcontracting-SBIR Phase I program. 1852.219-80 Section 1852.219-80 Federal Acquisition Regulations System... CLAUSES Texts of Provisions and Clauses 1852.219-80 Limitation on subcontracting—SBIR Phase I program. As prescribed in 1819.7302(a), insert the following clause: Limitation on Subcontracting—SBIR Phase I Program...

  15. 77 FR 44047 - Federal Acquisition Regulation; Reporting Executive Compensation and First-Tier Subcontract Awards

    Science.gov (United States)

    2012-07-26

    ...) at http://www.fsrs.gov . FSRS is a module of the Electronic Subcontracting Reporting System (eSRS... respondents stated that disclosing compensation information will create risk that a company may lose its key... (including construction) for the performance of a prime contract, but exclude supplier agreements that...

  16. 78 FR 17671 - Federal Acquisition Regulation; Submission for OMB Review; Summary Subcontract Report

    Science.gov (United States)

    2013-03-22

    ... business subcontracting program reporting process and provides the data to agencies in a manner that... quality and use of Federal information to strengthen decision- making, accountability, and openness in... to http://www.regulations.gov , including any personal and/or business confidential information...

  17. 48 CFR 1827.304-4 - Subcontracts. (NASA supplements paragraph (a))

    Science.gov (United States)

    2010-10-01

    ... supplements paragraph (a)) 1827.304-4 Section 1827.304-4 Federal Acquisition Regulations System NATIONAL... Rights Under Government Contracts 1827.304-4 Subcontracts. (NASA supplements paragraph (a)) (a)(i) Unless... or a subcontractor considers it inappropriate to include one of the clauses discussed in paragraph (a...

  18. Formal sector subcontracting and informal sector employment in Indian manufacturing : Author

    NARCIS (Netherlands)

    Moreno-Monroy, Ana I; Pieters, Janneke; Erumban, Abdul Azeez

    2014-01-01

    Using nationally representative survey data of Indian manufacturing enterprises spanning the period 1995–2006, we analyze the link between formal sector subcontracting and informal sector employment. A novelty in our analysis is that this relationship is allowed to differ between modern and

  19. Uranium Mill Tailings Remedial Action Project (UMTRAP), Slick Rock, Colorado, Revision 1. Bid schedule, special conditions, specifications, and subcontract drawings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-10-01

    This volume contains: bidding requirements; terms and conditions; specifications for Division 1 -- general requirements; specifications for Division 2 -- sitework; specifications for Divisions 5 -- metals; subcontract drawings, (general, Union Carbide processing site, North Continent processing site, and Burro Canyon disposal site).

  20. Hydrogen in semiconductors II

    CERN Document Server

    Nickel, Norbert H; Weber, Eicke R; Nickel, Norbert H

    1999-01-01

    Since its inception in 1966, the series of numbered volumes known as Semiconductors and Semimetals has distinguished itself through the careful selection of well-known authors, editors, and contributors. The "Willardson and Beer" Series, as it is widely known, has succeeded in publishing numerous landmark volumes and chapters. Not only did many of these volumes make an impact at the time of their publication, but they continue to be well-cited years after their original release. Recently, Professor Eicke R. Weber of the University of California at Berkeley joined as a co-editor of the series. Professor Weber, a well-known expert in the field of semiconductor materials, will further contribute to continuing the series' tradition of publishing timely, highly relevant, and long-impacting volumes. Some of the recent volumes, such as Hydrogen in Semiconductors, Imperfections in III/V Materials, Epitaxial Microstructures, High-Speed Heterostructure Devices, Oxygen in Silicon, and others promise that this tradition ...

  1. Basic Semiconductor Physics

    CERN Document Server

    Hamaguchi, Chihiro

    2010-01-01

    This book presents a detailed description of the basic semiconductor physics. The reader is assumed to have a basic command of mathematics and some elementary knowledge of solid state physics. The text covers a wide range of important phenomena in semiconductors, from the simple to the advanced. The reader can understand three different methods of energy band calculations, empirical pseudo-potential, k.p perturbation and tight-binding methods. The effective mass approximation and electron motion in a periodic potential, Boltzmann transport equation and deformation potentials used for full band Monte Carlo simulation are discussed. Experiments and theoretical analysis of cyclotron resonance are discussed in detail because the results are essential to the understanding of semiconductor physics. Optical and transport properties, magneto-transport, two dimensional electron gas transport (HEMT and MOSFET), and quantum transport are reviewed, explaining optical transition, electron phonon interactions, electron mob...

  2. Fundamentals of semiconductor lasers

    CERN Document Server

    Numai, Takahiro

    2015-01-01

    This book explains physics under the operating principles of semiconductor lasers in detail based on the experience of the author, dealing with the first manufacturing of phase-shifted DFB-LDs and recent research on transverse modes.   The book also bridges a wide gap between journal papers and textbooks, requiring only an undergraduate-level knowledge of electromagnetism and quantum mechanics, and helps readers to understand journal papers where definitions of some technical terms vary, depending on the paper. Two definitions of the photon density in the rate equations and two definitions of the phase-shift in the phase-shifted DFB-LD are explained, and differences in the calculated results are indicated, depending on the definitions.    Readers can understand the physics of semiconductor lasers and analytical tools for Fabry-Perot LDs, DFB-LDs, and VCSELs and will be stimulated to develop semiconductor lasers themselves.

  3. Compound semiconductor device physics

    CERN Document Server

    Tiwari, Sandip

    2013-01-01

    This book provides one of the most rigorous treatments of compound semiconductor device physics yet published. A complete understanding of modern devices requires a working knowledge of low-dimensional physics, the use of statistical methods, and the use of one-, two-, and three-dimensional analytical and numerical analysis techniques. With its systematic and detailed**discussion of these topics, this book is ideal for both the researcher and the student. Although the emphasis of this text is on compound semiconductor devices, many of the principles discussed will also be useful to those inter

  4. Semiconductor opto-electronics

    CERN Document Server

    Moss, TS; Ellis, B

    1972-01-01

    Semiconductor Opto-Electronics focuses on opto-electronics, covering the basic physical phenomena and device behavior that arise from the interaction between electromagnetic radiation and electrons in a solid. The first nine chapters of this book are devoted to theoretical topics, discussing the interaction of electromagnetic waves with solids, dispersion theory and absorption processes, magneto-optical effects, and non-linear phenomena. Theories of photo-effects and photo-detectors are treated in detail, including the theories of radiation generation and the behavior of semiconductor lasers a

  5. Introductory semiconductor device physics

    CERN Document Server

    Parker, Greg

    2004-01-01

    ATOMS AND BONDINGThe Periodic TableIonic BondingCovalent BondingMetallic bondingvan der Waals BondingStart a DatabaseENERGY BANDS AND EFFECTIVE MASSSemiconductors, Insulators and MetalsSemiconductorsInsulatorsMetalsThe Concept of Effective MassCARRIER CONCENTRATIONS IN SEMICONDUCTORSDonors and AcceptorsFermi-LevelCarrier Concentration EquationsDonors and Acceptors Both PresentCONDUCTION IN SEMICONDUCTORSCarrier DriftCarrier MobilitySaturated Drift VelocityMobility Variation with TemperatureA Derivation of Ohm's LawDrift Current EquationsSemiconductor Band Diagrams with an Electric Field Presen

  6. Ternary chalcopyrite semiconductors

    CERN Document Server

    Shay, J L; Pamplin, B R

    2013-01-01

    Ternary Chalcopyrite Semiconductors: Growth, Electronic Properties, and Applications covers the developments of work in the I-III-VI2 and II-IV-V2 ternary chalcopyrite compounds. This book is composed of eight chapters that focus on the crystal growth, characterization, and applications of these compounds to optical communications systems. After briefly dealing with the status of ternary chalcopyrite compounds, this book goes on describing the crystal growth of II-IV-V2 and I-III-VI2 single crystals. Chapters 3 and 4 examine the energy band structure of these semiconductor compounds, illustrat

  7. Optical processes in semiconductors

    CERN Document Server

    Pankove, Jacques I

    1975-01-01

    Based on a series of lectures at Berkeley, 1968-1969, this is the first book to deal comprehensively with all of the phenomena involving light in semiconductors. The author has combined, for the graduate student and researcher, a great variety of source material, journal research, and many years of experimental research, adding new insights published for the first time in this book.Coverage includes energy states in semiconductors and their perturbation by external parameters, absorption, relationships between optical constants, spectroscopy, radiative transitions, nonradiative recombination

  8. Growth of photovoltaic semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Yablonovitch, E. (Bell Communications Research, Red Bank, NJ (United States)); Stringfellow, G.B. (Univ. of Utah, Salt Lake City (United States)); Greene, J.E. (Univ. of Illinois, Urbana (United States))

    1993-01-01

    We assess the opportunities for improving the quality and lowering the cost of thin crystalline semiconductor films for photovoltaics. We find that novel growth and processing methods can lower the cost of crystalline semiconductor films to satisfy the economic conditions for a major expansion of the photovoltaic industry. The research requirements are in the areas of novel precursors for vapor phase growth, atomic layer epitaxy for unprecedented control, and the requirement for novel in situ and ex situ probes to ensure that the new growth methods are producing the utmost in photovoltaic material quality. 42 refs.

  9. Advances in semiconductor lasers

    CERN Document Server

    Coleman, James J; Jagadish, Chennupati

    2012-01-01

    Semiconductors and Semimetals has distinguished itself through the careful selection of well-known authors, editors, and contributors. Originally widely known as the ""Willardson and Beer"" Series, it has succeeded in publishing numerous landmark volumes and chapters. The series publishes timely, highly relevant volumes intended for long-term impact and reflecting the truly interdisciplinary nature of the field. The volumes in Semiconductors and Semimetals have been and will continue to be of great interest to physicists, chemists, materials scientists, and device engineers in academia, scien

  10. Metal semiconductor contacts and devices

    CERN Document Server

    Cohen, Simon S; Einspruch, Norman G

    1986-01-01

    VLSI Electronics Microstructure Science, Volume 13: Metal-Semiconductor Contacts and Devices presents the physics, technology, and applications of metal-semiconductor barriers in digital integrated circuits. The emphasis is placed on the interplay among the theory, processing, and characterization techniques in the development of practical metal-semiconductor contacts and devices.This volume contains chapters that are devoted to the discussion of the physics of metal-semiconductor interfaces and its basic phenomena; fabrication procedures; and interface characterization techniques, particularl

  11. Handbook of luminescent semiconductor materials

    CERN Document Server

    Bergman, Leah

    2011-01-01

    Photoluminescence spectroscopy is an important approach for examining the optical interactions in semiconductors and optical devices with the goal of gaining insight into material properties. With contributions from researchers at the forefront of this field, Handbook of Luminescent Semiconductor Materials explores the use of this technique to study semiconductor materials in a variety of applications, including solid-state lighting, solar energy conversion, optical devices, and biological imaging. After introducing basic semiconductor theory and photoluminescence principles, the book focuses

  12. Defects and diffusion in semiconductors XII

    CERN Document Server

    Fisher, David J

    2010-01-01

    This twelfth volume in the series covering the latest results in the field includes abstracts of papers which have appeared since the publication of Annual Retrospective XI (Volume 282). As well as the 565 semiconductor-related abstracts, the issue includes - in line with the policy of including original papers on all of the major material groups: ""Study of Conduction Mechanism in Amorphous Se85-xTe15Bix Thin Films"" (A.Sharma and P.B.Barman), ""Structure and Optical Properties of Magnetron-Sputtered SiOx Layers with Silicon Nanoparticles"" (L.Khomenkova, N.Korsunska, T.Stara, Y.Goldstein, J.

  13. Terahertz semiconductor nonlinear optics

    DEFF Research Database (Denmark)

    Turchinovich, Dmitry; Hvam, Jørn Märcher; Hoffmann, Matthias

    2013-01-01

    In this proceedings we describe our recent results on semiconductor nonlinear optics, investigated using single-cycle THz pulses. We demonstrate the nonlinear absorption and self-phase modulation of strong-field THz pulses in doped semiconductors, using n-GaAs as a model system. The THz nonlinear......In this proceedings we describe our recent results on semiconductor nonlinear optics, investigated using single-cycle THz pulses. We demonstrate the nonlinear absorption and self-phase modulation of strong-field THz pulses in doped semiconductors, using n-GaAs as a model system. The THz...... is determined by (but not equal to) the electron momentum relaxation rate. Single cycle pulses of light, irrespective of the frequency range to which they belong, inherently have an ultrabroadband spectrum covering many octaves of frequencies. Unlike the single-cycle pulses in optical domain, the THz pulses can...... be easily sampled with sub-cycle resolution using conventional femtosecond lasers. This makes the THz pulses accessible model tools for direct observation of general nonlinear optical phenomena occurring in the single-cycle regime....

  14. Physics of semiconductor devices

    Energy Technology Data Exchange (ETDEWEB)

    Prew, B.A.

    1975-09-01

    The properties of semiconductors which make them important in the electronic devices industry, and how these properties are controlled by doping, are described. The physics and applications of p-n and other junction devices, and of bulk effect devices are discussed. Avalanche devices, optical devices, solar cells, Schottky barriers, MOS devices, heterojunctions, photoconductors, and transferred electron devices are considered.

  15. Defects in semiconductor nanostructures

    Indian Academy of Sciences (India)

    11] A detailed review article of defects in semiconductor nanostructures is currently under preparation. [12] V Ranjan and Vijay A Singh, J. Appl. Phys. 89, 6415 (2001). [13] V Ranjan, R K Pandey, Manoj K Harbola and Vijay A Singh, Phys. Rev.

  16. Risk absorption in Japanese subcontracting : a microeconometirc study on the automobile industry

    OpenAIRE

    Asanuma, Banri; Kikutani, Tatsuya

    1991-01-01

    Prevalence of subcontracting in Japan has traditionally been ascribed to risk shifting behavior of manufacturers. But, Asanuma's field research has elicited the following. First, in transactions with those suppliers with which it maintains longstanding relations, each typical manufacturer absorbs risks to a nonnegligible degree. Second, the degree tends to be higher (1) the larger the share occupied by the manufacturer in the total sales of the supplier; and (2) the more rudimentary the categ...

  17. Downsizing nature: managing risk and knowledge economies through production subcontracting in the Oregon logging sector

    OpenAIRE

    W Scott Prudham

    2002-01-01

    The logging sector in Oregon is characterized by extensive subcontracting between wood-commodity manufacturing firms and independent logging contractors. Why is this so? Considerable recent scholarship has examined the dynamics of flexible production systems, including regional contractor networks, as prominent aspects of late capitalism. Although useful, existing accounts of flexibility are inadequate to explain why logging in particular would be subject to contract production relations. A s...

  18. Basic semiconductor physics

    CERN Document Server

    Hamaguchi, Chihiro

    2017-01-01

    This book presents a detailed description of basic semiconductor physics. The text covers a wide range of important phenomena in semiconductors, from the simple to the advanced. Four different methods of energy band calculations in the full band region are explained: local empirical pseudopotential, non-local pseudopotential, KP perturbation and tight-binding methods. The effective mass approximation and electron motion in a periodic potential, Boltzmann transport equation and deformation potentials used for analysis of transport properties are discussed. Further, the book examines experiments and theoretical analyses of cyclotron resonance in detail. Optical and transport properties, magneto-transport, two-dimensional electron gas transport (HEMT and MOSFET) and quantum transport are reviewed, while optical transition, electron-phonon interaction and electron mobility are also addressed. Energy and electronic structure of a quantum dot (artificial atom) are explained with the help of Slater determinants. The...

  19. Compound semiconductor device modelling

    CERN Document Server

    Miles, Robert

    1993-01-01

    Compound semiconductor devices form the foundation of solid-state microwave and optoelectronic technologies used in many modern communication systems. In common with their low frequency counterparts, these devices are often represented using equivalent circuit models, but it is often necessary to resort to physical models in order to gain insight into the detailed operation of compound semiconductor devices. Many of the earliest physical models were indeed developed to understand the 'unusual' phenomena which occur at high frequencies. Such was the case with the Gunn and IMPATI diodes, which led to an increased interest in using numerical simulation methods. Contemporary devices often have feature sizes so small that they no longer operate within the familiar traditional framework, and hot electron or even quantum­ mechanical models are required. The need for accurate and efficient models suitable for computer aided design has increased with the demand for a wider range of integrated devices for operation at...

  20. Single frequency semiconductor lasers

    CERN Document Server

    Fang, Zujie; Chen, Gaoting; Qu, Ronghui

    2017-01-01

    This book systematically introduces the single frequency semiconductor laser, which is widely used in many vital advanced technologies, such as the laser cooling of atoms and atomic clock, high-precision measurements and spectroscopy, coherent optical communications, and advanced optical sensors. It presents both the fundamentals and characteristics of semiconductor lasers, including basic F-P structure and monolithic integrated structures; interprets laser noises and their measurements; and explains mechanisms and technologies relating to the main aspects of single frequency lasers, including external cavity lasers, frequency stabilization technologies, frequency sweeping, optical phase locked loops, and so on. It paints a clear, physical picture of related technologies and reviews new developments in the field as well. It will be a useful reference to graduate students, researchers, and engineers in the field.

  1. Semiconductor physics an introduction

    CERN Document Server

    Seeger, Karlheinz

    1999-01-01

    Semiconductor Physics - An Introduction - is suitable for the senior undergraduate or new graduate student majoring in electrical engineering or physics. It will also be useful to solid-state scientists and device engineers involved in semiconductor design and technology. The text provides a lucid account of charge transport, energy transport and optical processes, and a detailed description of many devices. It includes sections on superlattices and quantum well structures, the effects of deep-level impurities on transport, the quantum Hall effect and the calculation of the influence of a magnetic field on the carrier distribution function. This 6th edition has been revised and corrected, and new sections have been added to different chapters.

  2. Infrared Semiconductor Metamaterials

    Science.gov (United States)

    2016-09-01

    AFRL-AFOSR-VA-TR-2016-0310 Infrared Semiconductor Metamaterials Jon Schuller UNIVERSITY OF CALIFORNIA SANTA BARBARA 3227 CHEADLE HL SANTA BARBARA, CA...S) AND ADDRESS(ES) University of California , Santa Barbara Office of Research, 3227 Cheadle Hall Santa Barbara, CA 93106-2050 8. PERFORMING...Using Heterojunction Resonators. Advanced Optical Materials, available online (2016). New discoveries, inventions, or patent disclosures: Do you have

  3. Nonradiative recombination in semiconductors

    CERN Document Server

    Abakumov, VN; Yassievich, IN

    1991-01-01

    In recent years, great progress has been made in the understandingof recombination processes controlling the number of excessfree carriers in semiconductors under nonequilibrium conditions. As a result, it is now possible to give a comprehensivetheoretical description of these processes. The authors haveselected a number of experimental results which elucidate theunderlying physical problems and enable a test of theoreticalmodels. The following topics are dealt with: phenomenological theory ofrecombination, theoretical models of shallow and deep localizedstates, cascade model of carrier captu

  4. Hole crystallization in semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Bonitz, M [Institut fuer Theoretische Physik und Astrophysik, Christian-Albrechts-Universitaet Kiel, 24098 Kiel (Germany); Filinov, V S [Institut fuer Theoretische Physik und Astrophysik, Christian-Albrechts-Universitaet Kiel, 24098 Kiel (Germany); Fortov, V E [Institute for High Energy Density, Russian Academy of Sciences, Izhorskay 13/19, Moscow 127412 (Russian Federation); Levashov, P R [Institute for High Energy Density, Russian Academy of Sciences, Izhorskay 13/19, Moscow 127412 (Russian Federation); Fehske, H [Institut fuer Physik, Universitaet Greifswald, l7487 Greifswald (Germany)

    2006-04-28

    When electrons in a solid are excited to a higher energy band they leave behind a vacancy (hole) in the original band which behaves like a positively charged particle. Here we predict that holes can spontaneously order into a regular lattice in semiconductors with sufficiently flat valence bands. The critical hole to electron effective mass ratio required for this phase transition is found to be of the order of 80.

  5. Hole crystallization in semiconductors

    OpenAIRE

    Bonitz, M.; Filinov, V. S.; Fortov, V. E.; Levashov, P. R.; Fehske, H.

    2005-01-01

    When electrons in a solid are excited to a higher energy band they leave behind a vacancy (hole) in the original band which behaves like a positively charged particle. Here we predict that holes can spontaneously order into a regular lattice in semiconductors with sufficiently flat valence bands. The critical hole to electron effective mass ratio required for this phase transition is found to be of the order of 80.

  6. Survey of semiconductor physics

    CERN Document Server

    Böer, Karl W

    1992-01-01

    Any book that covers a large variety of subjects and is written by one author lacks by necessity the depth provided by an expert in his or her own field of specialization. This book is no exception. It has been written with the encouragement of my students and colleagues, who felt that an extensive card file I had accumulated over the years of teaching solid state and semiconductor physics would be helpful to more than just a few of us. This file, updated from time to time, contained lecture notes and other entries that were useful in my research and permitted me to give to my students a broader spectrum of information than is available in typical textbooks. When assembling this material into a book, I divided the top­ ics into material dealing with the homogeneous semiconductor, the subject of the previously published Volume 1, and the inhomoge­ neous semiconductor, the subject of this Volume 2. In order to keep the book to a manageable size, sections of tutorial character which can be used as text for a g...

  7. Electrodes for Semiconductor Gas Sensors

    Science.gov (United States)

    Lee, Sung Pil

    2017-01-01

    The electrodes of semiconductor gas sensors are important in characterizing sensors based on their sensitivity, selectivity, reversibility, response time, and long-term stability. The types and materials of electrodes used for semiconductor gas sensors are analyzed. In addition, the effect of interfacial zones and surface states of electrode–semiconductor interfaces on their characteristics is studied. This study describes that the gas interaction mechanism of the electrode–semiconductor interfaces should take into account the interfacial zone, surface states, image force, and tunneling effect. PMID:28346349

  8. Method of passivating semiconductor surfaces

    Science.gov (United States)

    Wanlass, M.W.

    1990-06-19

    A method is described for passivating Group III-V or II-VI semiconductor compound surfaces. The method includes selecting a passivating material having a lattice constant substantially mismatched to the lattice constant of the semiconductor compound. The passivating material is then grown as an ultrathin layer of passivating material on the surface of the Group III-V or II-VI semiconductor compound. The passivating material is grown to a thickness sufficient to maintain a coherent interface between the ultrathin passivating material and the semiconductor compound. In addition, a device formed from such method is also disclosed.

  9. Layered semiconductor neutron detectors

    Science.gov (United States)

    Mao, Samuel S; Perry, Dale L

    2013-12-10

    Room temperature operating solid state hand held neutron detectors integrate one or more relatively thin layers of a high neutron interaction cross-section element or materials with semiconductor detectors. The high neutron interaction cross-section element (e.g., Gd, B or Li) or materials comprising at least one high neutron interaction cross-section element can be in the form of unstructured layers or micro- or nano-structured arrays. Such architecture provides high efficiency neutron detector devices by capturing substantially more carriers produced from high energy .alpha.-particles or .gamma.-photons generated by neutron interaction.

  10. Hydrogen in semiconductors

    CERN Document Server

    Pankove, Jacques I

    1991-01-01

    Hydrogen plays an important role in silicon technology, having a profound effect on a wide range of properties. Thus, the study of hydrogen in semiconductors has received much attention from an interdisciplinary assortment of researchers. This sixteen-chapter volume provides a comprehensive review of the field, including a discussion of hydrogenation methods, the use of hydrogen to passivate defects, the use of hydrogen to neutralize deep levels, shallow acceptors and shallow donors in silicon, vibrational spectroscopy, and hydrogen-induced defects in silicon. In addition to this detailed cove

  11. Physics of Organic Semiconductors

    CERN Document Server

    Brütting, Wolfgang

    2005-01-01

    Filling the gap in the literature currently available, this book presents an overview of our knowledge of the physics behind organic semiconductor devices. Contributions from 18 international research groups cover various aspects of this field, ranging from the growth of organic layers and crystals, their electronic properties at interfaces, their photophysics and electrical transport properties to the application of these materials in such different devices as organic field-effect transistors, photovoltaic cells and organic light-emitting diodes. From the contents:. * Excitation Dynamics in O

  12. Band structure of semiconductors

    CERN Document Server

    Tsidilkovski, I M

    2013-01-01

    Band Structure of Semiconductors provides a review of the theoretical and experimental methods of investigating band structure and an analysis of the results of the developments in this field. The book presents the problems, methods, and applications in the study of band structure. Topics on the computational methods of band structure; band structures of important semiconducting materials; behavior of an electron in a perturbed periodic field; effective masses and g-factors for the most commonly encountered band structures; and the treatment of cyclotron resonance, Shubnikov-de Haas oscillatio

  13. Basic properties of semiconductors

    CERN Document Server

    Landsberg, PT

    2013-01-01

    Since Volume 1 was published in 1982, the centres of interest in the basic physics of semiconductors have shifted. Volume 1 was called Band Theory and Transport Properties in the first edition, but the subject has broadened to such an extent that Basic Properties is now a more suitable title. Seven chapters have been rewritten by the original authors. However, twelve chapters are essentially new, with the bulk of this work being devoted to important current topics which give this volume an almost encyclopaedic form. The first three chapters discuss various aspects of modern band theory and the

  14. Doped semiconductor nanocrystal junctions

    Energy Technology Data Exchange (ETDEWEB)

    Borowik, Ł.; Mélin, T., E-mail: thierry.melin@isen.iemn.univ-lille1.fr [Institut d’Electronique, de Microélectronique et de Nanotechnologie, CNRS-UMR8520, Avenue Poincaré, F-59652 Villeneuve d’Ascq (France); Nguyen-Tran, T.; Roca i Cabarrocas, P. [Laboratoire de Physique des Interfaces et des Couches Minces, CNRS-UMR7647, Ecole Polytechnique, F-91128 Palaiseau (France)

    2013-11-28

    Semiconductor junctions are the basis of electronic and photovoltaic devices. Here, we investigate junctions formed from highly doped (N{sub D}≈10{sup 20}−10{sup 21}cm{sup −3}) silicon nanocrystals (NCs) in the 2–50 nm size range, using Kelvin probe force microscopy experiments with single charge sensitivity. We show that the charge transfer from doped NCs towards a two-dimensional layer experimentally follows a simple phenomenological law, corresponding to formation of an interface dipole linearly increasing with the NC diameter. This feature leads to analytically predictable junction properties down to quantum size regimes: NC depletion width independent of the NC size and varying as N{sub D}{sup −1/3}, and depleted charge linearly increasing with the NC diameter and varying as N{sub D}{sup 1/3}. We thus establish a “nanocrystal counterpart” of conventional semiconductor planar junctions, here however valid in regimes of strong electrostatic and quantum confinements.

  15. Squeezed light in semiconductors

    CERN Document Server

    Ward, M B

    2001-01-01

    Experimental evidence is presented for the generation of photon-number squeezed states of light as a result of multi-photon absorption. Photon-number squeezing as a result of non-linear absorption has long been predicted and results have been obtained utilising two very different material systems: (i) an AIGaAs waveguide in which high optical intensities can be maintained over a relatively long interaction length of 2 mm; (ii) the organic polymer p-toluene sulphonate polydiacetylene that is essentially a one-dimensional semiconductor possessing a highly nonlinear optical susceptibility. The resulting nonlinear absorption is shown to leave the transmitted light in a state that is clearly nonclassical, exhibiting photon-number fluctuations below the shot-noise limit. Tuning the laser wavelength across the half-bandgap energy has enabled a comparison between two- and three-photon processes in the semiconductor waveguide. The correlations created between different spectral components of a pulsed beam of light as ...

  16. II-VI semiconductor compounds

    CERN Document Server

    1993-01-01

    For condensed matter physicists and electronic engineers, this volume deals with aspects of II-VI semiconductor compounds. Areas covered include devices and applications of II-VI compounds; Co-based II-IV semi-magnetic semiconductors; and electronic structure of strained II-VI superlattices.

  17. Variable temperature semiconductor film deposition

    Science.gov (United States)

    Li, X.; Sheldon, P.

    1998-01-27

    A method of depositing a semiconductor material on a substrate is disclosed. The method sequentially comprises (a) providing the semiconductor material in a depositable state such as a vapor for deposition on the substrate; (b) depositing the semiconductor material on the substrate while heating the substrate to a first temperature sufficient to cause the semiconductor material to form a first film layer having a first grain size; (c) continually depositing the semiconductor material on the substrate while cooling the substrate to a second temperature sufficient to cause the semiconductor material to form a second film layer deposited on the first film layer and having a second grain size smaller than the first grain size; and (d) raising the substrate temperature, while either continuing or not continuing to deposit semiconductor material to form a third film layer, to thereby anneal the film layers into a single layer having favorable efficiency characteristics in photovoltaic applications. A preferred semiconductor material is cadmium telluride deposited on a glass/tin oxide substrate already having thereon a film layer of cadmium sulfide.

  18. Process for producing chalcogenide semiconductors

    Science.gov (United States)

    Noufi, R.; Chen, Y.W.

    1985-04-30

    A process for producing chalcogenide semiconductor material is disclosed. The process includes forming a base metal layer and then contacting this layer with a solution having a low pH and containing ions from at least one chalcogen to chalcogenize the layer and form the chalcogenide semiconductor material.

  19. Semiconductor materials and their properties

    NARCIS (Netherlands)

    Reinders, Angelina H.M.E.; Verlinden, Pierre; van Sark, Wilfried; Freundlich, Alexandre; Reinders, Angele; Verlinden, Pierre; van Sark, Wilfried; Freundlich, Alexandre

    2017-01-01

    Semiconductor materials are the basic materials which are used in photovoltaic (PV) devices. This chapter introduces solid-state physics and semiconductor properties that are relevant to photovoltaics without spending too much time on unnecessary information. Usually atoms in the group of

  20. Semiconductor photocatalysis principles and applications

    CERN Document Server

    Kisch, Horst

    2014-01-01

    Focusing on the basic principles of semiconductor photocatalysis, this book also gives a brief introduction to photochemistry, photoelectrochemistry, and homogeneous photocatalysis. In addition, the author - one of the leading authorities in the field - presents important environmental and practical aspects. A valuable, one-stop source for all chemists, material scientists, and physicists working in this area, as well as novice researchers entering semiconductor photocatalysis.

  1. Luminescence studies of semiconductor electrodes

    NARCIS (Netherlands)

    Kelly, J.J.; Kooij, Ernst S.; Meulenkamp, E.A.

    1999-01-01

    In this paper we review our recent results of in-situ luminescence studies of semiconductor electrodes. Three classes of materials are considered: single crystal compound semiconductors, porous silicon and semiconducting oxides doped with luminescent ions. We show how photoluminescence (PL) and

  2. Organic semiconductors in a spin

    CERN Document Server

    Samuel, I

    2002-01-01

    A little palladium can go a long way in polymer-based light-emitting diodes. Inorganic semiconductors such as silicon and gallium arsenide are essential for countless applications in everyday life, ranging from PCs to CD players. However, while they offer unrivalled computational speed, inorganic semiconductors are also rigid and brittle, which means that they are less suited to applications such as displays and flexible electronics. A completely different class of materials - organic semiconductors - are being developed for these applications. Organic semiconductors have many attractive features: they are easy to make, they can emit visible light, and there is tremendous scope for tailoring their properties to specific applications by changing their chemical structure. Research groups and companies around the world have developed a wide range of organic-semiconductor devices, including transistors, light-emitting diodes (LEDs), solar cells and lasers. (U.K.)

  3. Subcontracted Forms and “Intermediary” Agents of Employment Relationships: Foremen in the Construction Sector

    Directory of Open Access Journals (Sweden)

    Elife Kart

    2016-12-01

    Full Text Available Integration of flexible and precarious structure of employment conditions and relations with subcontracting strategies enables companies to conserve their competitive power in one sense; it also introduces the conditions, which are increasingly irregulated, temporal and destabilized, with regards to the labour power. On the other hand subcontracting, as a strategy of fragmenting, individualizing and isolating labour power in itself means that working conditions have been becoming more manageable in terms of capital. In this study, focusing on the positions of intermediary persons, defined as foremen in the labour market, especially in the construction sector, the strategies with which employment relationships become increasingly unsteady, indefinite and temporal are discussed. On the one hand, depending on the efforts of capital to reproduce itself on a global scale, the effects of capital on labour power are considered on the other, how these efforts produce the intermediary agents and through them how the labour power is instrumentilized as a tool of profit and productivity are analyzed. And the fabrication of the intermediary agents, which make the new forms of domination in employment relationships visible, is studied. The study is discussed through data gathered from in-depth interviews with subcontractors

  4. National Science Foundation - Annual Report 1985. Thirty-Fifth Annual Report for Fiscal Year 1985.

    Science.gov (United States)

    National Science Foundation, Washington, DC.

    The 35th Annual Report of the National Science Foundation (NSF) describes recent achievements of NSF sponsored research in viral structure, semiconductors, genetic engineering, Mayan culture, astronomy, physiology, paleontology, robotics, physics, material science and pollution. Major 1985 initiatives included: (1) establishing six university…

  5. Photocatalysis Using Semiconductor Nanoclusters

    Energy Technology Data Exchange (ETDEWEB)

    Thurston, T.R.; Wilcoxon,J.P.

    1999-01-21

    We report on experiments using nanosize MoS{sub 2} to photo-oxidize organic pollutants in water using visible light as the energy source. We have demonstrated that we can vary the redox potentials and absorbance characteristics of these small semiconductors by adjusting their size, and our studies of the photooxidation of organic molecules have revealed that the rate of oxidation increases with increasing bandgap (i.e. more positive valence band and more negative conduction band potentials). Because these photocatalysis reactions can be performed with the nanoclusters fully dispersed and stable in solution, liquid chromatography can be used to determine both the intermediate reaction products and the state of the nanoclusters during the reaction. We have demonstrated that the MoS{sub 2} nanoclusters remain unchanged during the photooxidation process by this technique. We also report on studies of MoS{sub 2} nanoclusters deposited on TiO{sub 2} powder.

  6. Semiconductor radiation detector

    Science.gov (United States)

    Bell, Zane W.; Burger, Arnold

    2010-03-30

    A semiconductor detector for ionizing electromagnetic radiation, neutrons, and energetic charged particles. The detecting element is comprised of a compound having the composition I-III-VI.sub.2 or II-IV-V.sub.2 where the "I" component is from column 1A or 1B of the periodic table, the "II" component is from column 2B, the "III" component is from column 3A, the "IV" component is from column 4A, the "V" component is from column 5A, and the "VI" component is from column 6A. The detecting element detects ionizing radiation by generating a signal proportional to the energy deposited in the element, and detects neutrons by virtue of the ionizing radiation emitted by one or more of the constituent materials subsequent to capture. The detector may contain more than one neutron-sensitive component.

  7. Semiconductor optoelectronic infrared spectroscopy

    CERN Document Server

    Hollingworth, A R

    2001-01-01

    level separation. This showed for the first time evidence of the phonon bottleneck in a working laser device. A new technique called time resolved optically detected cyclotron resonance, was used as a precursor to finding the carrier dynamics within a spatially confined quantum dot. By moving to the case of a spatial QD using an optically detected intraband resonance it was possible to measure the energy separation interband levels and conduction and valence sublevels within the dot simultaneously. Furthermore this technique has been shown that the inhomogeneous broadening of the photoluminescence spectrum is not purely affected by just size and composition. We suggest that other processes such as state occupancy, In roughing, and exciton binding energies may account for the extra energy. We use spectroscopy to study infrared optoelectronic inter and intraband semiconductor carrier dynamics. The overall aim of this thesis was to study both III-V and Pb chalcogenide material systems in order to show their futu...

  8. Semiconductor adiabatic qubits

    Energy Technology Data Exchange (ETDEWEB)

    Carroll, Malcolm S.; Witzel, Wayne; Jacobson, Noah Tobias; Ganti, Anand; Landahl, Andrew J.; Lilly, Michael; Nguyen, Khoi Thi; Bishop, Nathaniel; Carr, Stephen M.; Bussmann, Ezra; Nielsen, Erik; Levy, James Ewers; Blume-Kohout, Robin J.; Rahman, Rajib

    2016-12-27

    A quantum computing device that includes a plurality of semiconductor adiabatic qubits is described herein. The qubits are programmed with local biases and coupling terms between qubits that represent a problem of interest. The qubits are initialized by way of a tuneable parameter, a local tunnel coupling within each qubit, such that the qubits remain in a ground energy state, and that initial state is represented by the qubits being in a superposition of |0> and |1> states. The parameter is altered over time adiabatically or such that relaxation mechanisms maintain a large fraction of ground state occupation through decreasing the tunnel coupling barrier within each qubit with the appropriate schedule. The final state when tunnel coupling is effectively zero represents the solution state to the problem represented in the |0> and |1> basis, which can be accurately read at each qubit location.

  9. Wetland Biomass Production: emergent aquatic management options and evaluations. A final subcontract report. [Includes a bibliography containing 686 references on Typha from biological abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Pratt, D.C.; Dubbe, D.R.; Garver, E.G.; Linton, P.J.

    1984-07-01

    The high yield potential and attractive chemical composition of Typha make it a particularly viable energy crop. The Minnesota research effort has demonstrated that total annual biomass yields equivalent to 30 dry tonnes/ha (13 tons/acre) are possible in planted stands. This compares with yields of total plant material between 9 and 16 dry tonnes/ha (4 to 7 tons/acre) in a typical Minnesota corn field. At least 50% of the Typha plant is comprised of a belowground rhizome system containing 40% starch and sugar. This high level of easily fermentable carbohydrate makes rhizomes an attractive feedstock for alcohol production. The aboveground portion of the plant is largely cellulose, and although it is not easily fermentable, it can be gasified or burned. This report is organized in a manner that focuses on the evaluation of the management options task. Results from stand management research performed at the University of Minnesota during 1982 and 1983 are integrated with findings from an extensive survey of relevant emergent aquatic plant research and utilization. These results and findings are then arranged in sections dealing with key steps and issues that need to be dealt with in the development of a managed emergent aquatic bio-energy system. A brief section evaluating the current status of rhizome harvesting is also included along with an indexed bibliography of the biology, ecology, and utilization of Typha which was completed with support from this SERI subcontract. 686 references, 11 figures, 17 tables.

  10. 48 CFR 927.404 - Rights in technical data in subcontracts. (DOE coverage-paragraphs (g), (k), (l), and (m))

    Science.gov (United States)

    2010-10-01

    ... copyright in any computer software first produced in the performance of the contract. This requirement reflects DOE's established software distribution program, recognized at FAR 27.404(g)(2), and the... COPYRIGHTS Technical Data and Copyrights 927.404 Rights in technical data in subcontracts. (DOE coverage...

  11. Semiconductor-superconductor optoelectronic devices

    Science.gov (United States)

    Bouscher, Shlomi; Panna, Dmitry; Hayat, Alex

    2017-10-01

    Devices combining superconductors with semiconductors offer a wide range of applications, particularly in the growing field of quantum information processing. This is due to their ability to take advantage of both the extensive knowledge gathered in the field of semiconductors and the unique quantum properties of superconductors. This results in novel device concepts, such as structures generating and detecting entangled photon pairs as well as novel optical gain and laser realizations. In this review, we discuss the fundamental concepts and the underlying physical phenomena of superconductor-semiconductor optoelectronics as well as practical device implementations.

  12. Semiconductor Nanocrystals for Biological Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Aihua; Gu, Weiwei; Larabell, Carolyn; Alivisatos, A. Paul

    2005-06-28

    Conventional organic fluorophores suffer from poor photo stability, narrow absorption spectra and broad emission feature. Semiconductor nanocrystals, on the other hand, are highly photo-stable with broad absorption spectra and narrow size-tunable emission spectra. Recent advances in the synthesis of these materials have resulted in bright, sensitive, extremely photo-stable and biocompatible semiconductor fluorophores. Commercial availability facilitates their application in a variety of unprecedented biological experiments, including multiplexed cellular imaging, long-term in vitro and in vivo labeling, deep tissue structure mapping and single particle investigation of dynamic cellular processes. Semiconductor nanocrystals are one of the first examples of nanotechnology enabling a new class of biomedical applications.

  13. Lessons learned from the EG&G consolidated hazardous waste subcontract and ESH&Q liability assessment process

    Energy Technology Data Exchange (ETDEWEB)

    Fix, N.J.

    1995-03-01

    Hazardous waste transportation, treatment, recycling, and disposal contracts were first consolidated at the Idaho National Engineering Laboratory in 1992 by EG&G Idaho, Inc. At that time, disposition of Resource, Conservation and Recovery Act hazardous waste, Toxic Substance Control Act waste, Comprehensive Environmental Response, Compensation, and Liability Act hazardous substances and contaminated media, and recyclable hazardous materials was consolidated under five subcontracts. The wastes were generated by five different INEL M&O contractors, under the direction of three different Department of Energy field offices. The consolidated contract reduced the number of facilities handling INEL waste from 27 to 8 qualified treatment, storage, and disposal facilities, with brokers specifically prohibited. This reduced associated transportation costs, amount and cost of contractual paperwork, and environmental liability exposure. EG&G reviewed this approach and proposed a consolidated hazardous waste subcontract be formed for the major EG&G managed DOE sites: INEL, Mound, Rocky Flats, Nevada Test Site, and 10 satellite facilities. After obtaining concurrence from DOE Headquarters, this effort began in March 1992 and was completed with the award of two master task subcontracts in October and November 1993. In addition, the effort included a team to evaluate the apparent awardee`s facilities for environment, safety, health, and quality (ESH&Q) and financial liability status. This report documents the evaluation of the process used to prepare, bid, and award the EG&G consolidated hazardous waste transportation, treatment, recycling, and/or disposal subcontracts and associated ESH&Q and financial liability assessments; document the strengths and weaknesses of the process; and propose improvements that would expedite and enhance the process for other DOE installations that used the process and for the re-bid of the consolidated subcontract, scheduled for 1997.

  14. Toward designing semiconductor-semiconductor heterojunctions for photocatalytic applications

    Science.gov (United States)

    Zhang, Liping; Jaroniec, Mietek

    2018-02-01

    Semiconductor photocatalysts show a great potential for environmental and energy-related applications, however one of the major disadvantages is their relatively low photocatalytic performance due to the recombination of electron-hole pairs. Therefore, intensive research is being conducted toward design of heterojunctions, which have been shown to be effective for improving the charge-transfer properties and efficiency of photocatalysts. According to the type of band alignment and direction of internal electric field, heterojunctions are categorized into five different types, each of which is associated with its own charge transfer characteristics. Since the design of heterojunctions requires the knowledge of band edge positions of component semiconductors, the commonly used techniques for the assessment of band edge positions are reviewed. Among them the electronegativity-based calculation method is applied for a large number of popular visible-light-active semiconductors, including some widely investigated bismuth-containing semiconductors. On basis of the calculated band edge positions and the type of component semiconductors reported, heterojunctions composed of the selected bismuth-containing semiconductors are proposed. Finally, the most popular synthetic techniques for the fabrication of heterojunctions are briefly discussed.

  15. Atomic layer deposition for semiconductors

    CERN Document Server

    Hwang, Cheol Seong

    2014-01-01

    This edited volume discusses atomic layer deposition (ALD) for all modern semiconductor devices, moving from the basic chemistry of ALD and modeling of ALD processes to sections on ALD for memories, logic devices, and machines.

  16. Semiconductor radiation detectors. Device physics

    Energy Technology Data Exchange (ETDEWEB)

    Lutz, G. [Max-Planck-Institutes for Physics and Extraterrestrial Physics, Muenchen (Germany). Semiconductor Lab.

    2007-07-01

    Starting from basic principles, the author, whose own contributions to these developments have been significant, describes the rapidly growing field of modern semiconductor detectors used for energy and position measurement radiation. This development was stimulated by requirements in elementary particle physics where it has led to important scientific discoveries. It has now spread to many other fields of science and technology. The book is written in a didactic way and includes an introduction to semiconductor physics. The working principles of semiconductor radiation detectors are explained in an intuitive way, followed by formal quantitative analysis. Broad coverage is also given to electronic signal readout and to the subject of radiation damage. The book is the first to comprehensively cover the semiconductor radiation detectors currently in use. It is useful as a teaching guide and as a reference work for research and applications. (orig.)

  17. Physics of semiconductor laser devices

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, G.H.B.

    1980-01-01

    Aspects of laser design and development are considered along with semiconductor materials for lasers, problems of device fabrication, crystal growth, the degradation of lasers, and the integration of semiconductor lasers with other optical components. A description is presented of light emission processes and laser action in semiconductors, taking into account electronic radiative transitions, the relation between emission and absorption processes, transition probabilities, the density of electron states in the highly doped semiconductor, carrier recombination and spontaneous emission, the gain/current relation, light-current characteristics, optical modes, and the evolution of mode spectrum and intensity with current. Attention is given to laser heterostructures and the properties of heterojunctions, optical waveguides, the performance of heterostructure lasers, stripe geometry lasers, and the dynamic response of lasers. Lasers with distributed feedback and Bragg reflectors are also discussed.

  18. Energy transfer with semiconductor nanocrystals

    NARCIS (Netherlands)

    Rogach, A.L.; Klar, T.A.; Lupton, J.M.; Meijerink, A.; Feldmann, J.

    2009-01-01

    Fo¨ rster (or fluorescence) resonant energy transfer (FRET) is a powerful spectroscopic technique to study interactions, conformational and distance changes, in hybrid nanosystems. Semiconductor nanocrystals, also known as colloidal quantum dots, are highly efficient fluorophores with a strong

  19. Ballistic superconductivity in semiconductor nanowires

    NARCIS (Netherlands)

    Zhang, H.; Gül, Ö.; Conesa-Boj, S.; Nowak, M.P.; Wimmer, M.; Zuo, K.; Mourik, V.; Vries, F.K. de; Veen, J. van; Moor, M.W.A. de; Bommer, J.D.S.; Woerkom, D.J. van; Car, D.; Plissard, S.R.; Bakkers, E.P.A.M.; Quintero Pérez, M.; Cassidy, M.C.; Koelling, S.; Goswami, S.; Watanabe, K.; Taniguchi, T.; Kouwenhoven, L.P.

    2017-01-01

    Semiconductor nanowires have opened new research avenues in quantum transport owing to their confined geometry and electrostatic tunability. They have offered an exceptional testbed for superconductivity, leading to the realization of hybrid systems combining the macroscopic quantum properties of

  20. Quantum optics with semiconductor nanostructures

    CERN Document Server

    Jahnke, Frank

    2012-01-01

    A guide to the theory, application and potential of semiconductor nanostructures in the exploration of quantum optics. It offers an overview of resonance fluorescence emission.$bAn understanding of the interaction between light and matter on a quantum level is of fundamental interest and has many applications in optical technologies. The quantum nature of the interaction has recently attracted great attention for applications of semiconductor nanostructures in quantum information processing. Quantum optics with semiconductor nanostructures is a key guide to the theory, experimental realisation, and future potential of semiconductor nanostructures in the exploration of quantum optics. Part one provides a comprehensive overview of single quantum dot systems, beginning with a look at resonance fluorescence emission. Quantum optics with single quantum dots in photonic crystal and micro cavities are explored in detail, before part two goes on to review nanolasers with quantum dot emitters. Light-matter interaction...

  1. Semiconductor nanocrystals or quantum dots

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 18; Issue 8. Various Quantum Mechanical Concepts for Confinements in Semiconductor Nanocrystals. Jayakrishna Khatei Karuna Kar Nanda. Classroom Volume 18 Issue 8 August 2013 pp 771-776 ...

  2. Semiconductor packaging materials interaction and reliability

    CERN Document Server

    Chen, Andrea

    2012-01-01

    In semiconductor manufacturing, understanding how various materials behave and interact is critical to making a reliable and robust semiconductor package. Semiconductor Packaging: Materials Interaction and Reliability provides a fundamental understanding of the underlying physical properties of the materials used in a semiconductor package. The book focuses on an important step in semiconductor manufacturing--package assembly and testing. It covers the basics of material properties and explains how to determine which behaviors are important to package performance. The authors also discuss how

  3. Fractal properties of nanostructured semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Zhanabaev, Z.Zh. [Al-Farabi Khazakh National University, Tole bi Street, 96, Almaty 050012 (Kazakhstan); Grevtseva, T.Yu. [Al-Farabi Khazakh National University, Tole bi Street, 96, Almaty 050012 (Kazakhstan)]. E-mail: kenwp@mail.ru

    2007-03-15

    A theory for the temperature and time dependence of current carrier concentration in semiconductors with different non-equilibrium nanocluster structure has been developed. It was shown that the scale-invariant fractal self-similar and self-affine laws can exist near by the transition point to the equilibrium state. Results of the theory have been compared to the experimental data from electrical properties of semiconductor films with nanoclusters.

  4. Dissipative chaos in semiconductor superlattices

    Directory of Open Access Journals (Sweden)

    F. Moghadam

    2008-03-01

    Full Text Available In this paper the motion of electron in a miniband of a semiconductor superlattice (SSL under the influence of external electric and magnetic fields is investigated. The electric field is applied in a direction perpendicular to the layers of the semiconductor superlattice, and the magnetic field is applied in different direction Numerical calculations show conditions led to the possibility of chaotic behaviors.

  5. Nonlinear Optical Interactions in Semiconductors.

    Science.gov (United States)

    1985-12-10

    Physique du Solide et Energie Solaire We had on-going interaction with Dr. Christian Verie on the growth of high quality narrow-gap semiconductor crystals...The band gap energy of the semiconductor decreases with increasing temperature. Consequently, the absorption of light in the energy region of the...gas and, more importantly, will modulate the electron energy at the difference frequency, wI - 02" Under ordinary circumstances such an energy (or

  6. Survey of cryogenic semiconductor devices

    Energy Technology Data Exchange (ETDEWEB)

    Talarico, L.J.; McKeever, J.W.

    1996-04-01

    Improved reliability and electronic performance can be achieved in a system operated at cryogenic temperatures because of the reduction in mechanical insult and in disruptive effects of thermal energy on electronic devices. Continuing discoveries of new superconductors with ever increasing values of T{sub c} above that of liquid nitrogen temperature (LNT) have provided incentive for developing semiconductor electronic systems that may also operate in the superconductor`s liquid nitrogen bath. Because of the interest in high-temperature superconductor (HTS) devices, liquid nitrogen is the cryogen of choice and LNT is the temperature on which this review is focused. The purpose of this survey is to locate and assemble published information comparing the room temperature (298 K), performance of commercially available conventional and hybrid semiconductor device with their performance at LNT (77K), to help establish their candidacy as cryogenic electronic devices specifically for use at LNT. The approach to gathering information for this survey included the following activities. Periodicals and proceedings were searched for information on the behavior of semiconductor devices at LNT. Telephone calls were made to representatives of semiconductor industries, to semiconductor subcontractors, to university faculty members prominent for their research in the area of cryogenic semiconductors, and to representatives of the National Aeronautics and Space Administration (NASA) and NASA subcontractors. The sources and contacts are listed with their responses in the introduction, and a list of references appears at the end of the survey.

  7. The ATLAS semiconductor tracker

    CERN Document Server

    Mikuz, Marko

    2003-01-01

    The ATLAS Semiconductor Tracker (SCT) is presented. About 16000 silicon micro-strip sensors with a total active surface of over 60 m **2 and with 6.3 million read-out channels are built into 4088 modules arranged into four barrel layers and nine disks covering each of the forward regions up to an eta of 2.5. Challenges are imposed by the hostile radiation environment with particle fluences up to 2 multiplied by 10**1**4 cm**-**2 1 MeV neutron NIEL equivalent and 100 kGy TID, the 25 ns LHC bunch crossing time and the need for a hermetic, lightweight tracker. The solution adopted is carefully designed strip detectors operated at -7 degree C, biased up to 500 V and read out by binary radhard fast BiCMOS electronics. A zero-CTE carbon fibre structure provides mechanical support. 30 kW of power are supplied on aluminiutn/Kapton tapes and cooled by C//3F//8 evaporative cooling. Data and commands are transferred by optical links. Prototypes of detector modules have been built, irradiated to the maximum expected flue...

  8. EDITORIAL: Oxide semiconductors

    Science.gov (United States)

    Kawasaki, M.; Makino, T.

    2005-04-01

    Blue or ultraviolet semiconducting light-emitting diodes have the potential to revolutionize illumination systems in the near-future. Such industrial need has propelled the investigation of several wide-gap semiconducting materials in recent years. Commercial applications include blue lasers for DVD memory and laser printers, while military applications are also expected. Most of the material development has so far been focused on GaN (band gap 3.5 eV at 2 K), and ZnSe (2.9 eV) because these two representative direct transition semiconductors are known to be bright emitting sources. GaN and GaN-based alloys are emerging as the winners in this field because ZnSe is subject to defect formation under high current drive. On the other hand, another II-VI compound, ZnO, has also excited substantial interest in the optoelectronics-oriented research communities because it is the brightest emitter of all, owing to the fact that its excitons have a 60 meV binding energy. This is compared with 26 meV for GaN and 20 meV for ZnSe. The stable excitons could lead to laser action based on their recombination even at temperatures well above room temperature. ZnO has additional major properties that are more advantageous than other wide-gap materials: availability of large area substrates, higher energy radiation stability, environmentally-friendly ingredients, and amenability to wet chemical etching. However, ZnO is not new to the semiconductor field as exemplified by several studies made during the 1960s on structural, vibrational, optical and electrical properties (Mollwo E 1982 Landolt-Boernstein New Series vol 17 (Berlin: Springer) p 35). In terms of devices, the luminescence from light-emitting diode structures was demonstrated in which Cu2O was used as the p-type material (Drapak I T 1968 Semiconductors 2 624). The main obstacle to the development of ZnO has been the lack of reproducible p-type ZnO. The possibility of achieving epitaxial p-type layers with the aid of thermal

  9. Wide-Bandgap Semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Chinthavali, M.S.

    2005-11-22

    With the increase in demand for more efficient, higher-power, and higher-temperature operation of power converters, design engineers face the challenge of increasing the efficiency and power density of converters [1, 2]. Development in power semiconductors is vital for achieving the design goals set by the industry. Silicon (Si) power devices have reached their theoretical limits in terms of higher-temperature and higher-power operation by virtue of the physical properties of the material. To overcome these limitations, research has focused on wide-bandgap materials such as silicon carbide (SiC), gallium nitride (GaN), and diamond because of their superior material advantages such as large bandgap, high thermal conductivity, and high critical breakdown field strength. Diamond is the ultimate material for power devices because of its greater than tenfold improvement in electrical properties compared with silicon; however, it is more suited for higher-voltage (grid level) higher-power applications based on the intrinsic properties of the material [3]. GaN and SiC power devices have similar performance improvements over Si power devices. GaN performs only slightly better than SiC. Both SiC and GaN have processing issues that need to be resolved before they can seriously challenge Si power devices; however, SiC is at a more technically advanced stage than GaN. SiC is considered to be the best transition material for future power devices before high-power diamond device technology matures. Since SiC power devices have lower losses than Si devices, SiC-based power converters are more efficient. With the high-temperature operation capability of SiC, thermal management requirements are reduced; therefore, a smaller heat sink would be sufficient. In addition, since SiC power devices can be switched at higher frequencies, smaller passive components are required in power converters. Smaller heat sinks and passive components result in higher-power-density power converters

  10. Semiconductor lasers stability, instability and chaos

    CERN Document Server

    Ohtsubo, Junji

    2017-01-01

    This book describes the fascinating recent advances made concerning the chaos, stability and instability of semiconductor lasers, and discusses their applications and future prospects in detail. It emphasizes the dynamics in semiconductor lasers by optical and electronic feedback, optical injection, and injection current modulation. Applications of semiconductor laser chaos, control and noise, and semiconductor lasers are also demonstrated. Semiconductor lasers with new structures, such as vertical-cavity surface-emitting lasers and broad-area semiconductor lasers, are intriguing and promising devices. Current topics include fast physical number generation using chaotic semiconductor lasers for secure communication, development of chaos, quantum-dot semiconductor lasers and quantum-cascade semiconductor lasers, and vertical-cavity surface-emitting lasers. This fourth edition has been significantly expanded to reflect the latest developments. The fundamental theory of laser chaos and the chaotic dynamics in se...

  11. Photoreflectance Characterization of Semiconductors

    Science.gov (United States)

    Bhimnathwala, Hemant Ghanshyamdas

    Photoreflectance technique has been used as a non-destructive probe of surface photo-voltage in doped and semi-insulating semiconductors. A system used to measure the photoreflectance spectra near the fundamental gap of GaAs and InP has been described. Measurements as a function of pump intensity on n and p type GaAs were used to infer the carrier dynamics leading to change in the surface electric field. Measurements indicate that the surface of GaAs consists of hole traps at the surface in addition to recombination states. This is confirmed by spectroscopic studies carried out by varying the pump modulation frequency at fixed temperatures and the measurements show that the hole trap has an activation energy of 0.29 eV and has an emission time of 0.175 +/- 0.002 msec. at room temperature. In semi-insulating GaAs, it is expected that there is no surface electric field at equilibrium due to pinning at the surface and large concentration of deep defect EL2. Electromodulation, in this case proceeds via preferential trapping of holes at the surface. This is supported by measurements carried out as a function of pump intensity and on wafers having different carbon concentrations. Analysis of carrier dynamics in semi-insulating GaAs is much simplified by use of Nd:YAG laser (instead of a HeNe laser) as a source of pump beam. A sub-band -gap excitation generates mainly excess electrons and the Poisson's equation can be integrated once to find the surface electric field. Numerical integration yields the surface photovoltage. It is shown that this technique is sensitive to the the surface state density and relatively insensitive to bulk properties. It has been applied to study the effect of various chemical reactants on the surface state density. In many PR spectra, features at energies less than the gap energy are observed. These are ascribed to shallow acceptors unrelated to carbon, which was the dominant acceptor in these materials. It is proposed that the electric field

  12. Physics of semiconductor laser devices

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, G.H.B.

    1980-01-01

    The physics of the semiconductor laser is studied. The basic phenomena that control the operation of the device are analyzed and described in considerable detail. The treatment has been keyed particularly to fundamental concepts and kept general in order to avoid being overtaken by events. The range of phenomena in a semiconductor laser involves a number of scientific disciplines. To cater for the reader who is not already a specialist in all of these the author has endeavoured, in the chapters on fundamental behaviour, to provide in a readable form the minimum background that is needed to understand the more specialist part of the text. As an introduction a general review is given of the whole range of semiconductor laser devices that now exist, the technology involved in their fabrication, the factors that determine their reliability, and their possible role in integrated systems.

  13. Thiophene-Based Organic Semiconductors.

    Science.gov (United States)

    Turkoglu, Gulsen; Cinar, M Emin; Ozturk, Turan

    2017-10-24

    Thiophene-based π-conjugated organic small molecules and polymers are the research subject of significant current interest owing to their potential use as organic semiconductors in material chemistry. Despite simple and similar molecular structures, the hitherto reported properties of thiophene-based organic semiconductors are rather diverse. Design of high performance organic semiconducting materials requires a thorough understanding of inter- and intra-molecular interactions, solid-state packing, and the influence of both factors on the charge carrier transport. In this chapter, thiophene-based organic semiconductors, which are classified in terms of their chemical structures and their structure-property relationships, are addressed for the potential applications as organic photovoltaics (OPVs), organic field-effect transistors (OFETs) and organic light emitting diodes (OLEDs).

  14. High pressure semiconductor physics I

    CERN Document Server

    Willardson, R K; Paul, William; Suski, Tadeusz

    1998-01-01

    Since its inception in 1966, the series of numbered volumes known as Semiconductors and Semimetals has distinguished itself through the careful selection of well-known authors, editors, and contributors. The "Willardson and Beer" Series, as it is widely known, has succeeded in publishing numerous landmark volumes and chapters. Not only did many of these volumes make an impact at the time of their publication, but they continue to be well-cited years after their original release. Recently, Professor Eicke R. Weber of the University of California at Berkeley joined as a co-editor of the series. Professor Weber, a well-known expert in the field of semiconductor materials, will further contribute to continuing the series' tradition of publishing timely, highly relevant, and long-impacting volumes. Some of the recent volumes, such as Hydrogen in Semiconductors, Imperfections in III/V Materials, Epitaxial Microstructures, High-Speed Heterostructure Devices, Oxygen in Silicon, and others promise indeed that this tra...

  15. Specific PVMaT R&D in CdTe Product Manufacturing: Final Subcontract Report, March 2003

    Energy Technology Data Exchange (ETDEWEB)

    Bohland, J.; McMaster, A.; Henson, S.; Hanak, J.

    2004-01-01

    Results of a 3+ year subcontract are presented. The research was conducted under Phase 5A2 of the subcontract. The three areas of effort in the subcontract were (1) manufacturing line improvements, (2) product readiness, and (3) environmental, safety, and health programs. The subcontract consisted of three phases, approximately 1 year each. Phase I included the development, design, and implementation of a high-throughput, low-cost lamination process. This goal was achieved using the support of key experts such as Automation and Robotics Research Institute (ARRI) to identify appropriate lamination equipment vendors, and material handling. Product designs were reviewed by Arizona State University Photovoltaic Testing Laboratory and Underwriters Laboratories. Modifications to the module designs were implemented to meet future testing requirements. A complete review of the Environmental, Health, and Safety programs was conducted, along with training by the Environmental Protection Agency (EP A) and Occupational Safety and Health Administration (OSHA). Work conducted during Phase II included the implementation of an improved potting procedure for the wiring junction. The design of the equipment focused on high-throughput, low-cost operations. During Phase III , First Solar made significant progress in three areas: Manufacturing Readiness; Product Performance; and Environmental, Health, and Safety (EH&S). First Solar's accomplishments in laser scribing significantly exceeded the stated goals. Innovations implemented during Phase III were made possible by adopting a new type of high-frequency, low-pulse-width laser, galvanometer-driven laser-beam system, and numerous advanced, automated, equipment features. Because of the greater than one order of magnitude increase in the throughput and laser life, a factor of two decrease in equipment cost, and complete automation, a major impact on lowering the cost of the PV product is anticipated.

  16. NCI Takes Back the Defelice Cup at Ninth Annual Golf Tournament | Poster

    Science.gov (United States)

    By Ashley DeVine, Staff Writer After being down by a point in the morning, NCI reclaimed the Defelice Cup trophy from Leidos Biomedical Research, with a final score of 12 ½ to 11 ½, at the ninth annual Ronald H. Defelice Golf Tournament, held Oct. 13. “The tightest matches in the nine-year history of this cup competition resulted in a narrow victory for NCI and allowed NCI to take a 5–4 victory total,” said Denny Dougherty, one of the team captains for Leidos Biomed and a retired senior subcontracts advisor at what was formerly SAIC-Frederick.

  17. Semiconductor device physics and simulation

    CERN Document Server

    Yuan, J S

    1998-01-01

    This volume provides thorough coverage of modern semiconductor devices -including hetero- and homo-junction devices-using a two-dimensional simulator (MEDICI) to perform the analysis and generate simulation results Each device is examined in terms of dc, ac, and transient simulator results; relevant device physics; and implications for design and analysis Two hundred forty-four useful figures illustrate the physical mechanisms and characteristics of the devices simulated Comprehensive and carefully organized, Semiconductor Device Physics and Simulation is the ideal bridge from device physics to practical device design

  18. Optical coherent control in semiconductors

    DEFF Research Database (Denmark)

    Østergaard, John Erland; Vadim, Lyssenko; Hvam, Jørn Märcher

    2001-01-01

    The developments with coherent control (CC) techniques in optical spectroscopy have recently demonstrated population control and coherence manipulations when the induced optical phase is explored with phase-locked laser pulses. These and other developments have been guiding the new research field...... of quantum control including the recent applications to semiconductors and nanostructures. We study the influence of inhomogeneous broadening in semiconductors on CC results. Photoluminescence (PL) and the coherent emission in four-wave mixing (FWM) is recorded after resonant excitation with phase-locked...

  19. Semiconductor lasers and herterojunction leds

    CERN Document Server

    Kressel, Henry

    2012-01-01

    Semiconductor Lasers and Heterojunction LEDs presents an introduction to the subject of semiconductor lasers and heterojunction LEDs. The book reviews relevant basic solid-state and electromagnetic principles; the relevant concepts in solid state physics; and the p-n junctions and heterojunctions. The text also describes stimulated emission and gain; the relevant concepts in electromagnetic field theory; and the modes in laser structures. The relation between electrical and optical properties of laser diodes; epitaxial technology; binary III-V compounds; and diode fabrication are also consider

  20. Semiconductors and semimetals epitaxial microstructures

    CERN Document Server

    Willardson, Robert K; Beer, Albert C; Gossard, Arthur C

    1994-01-01

    Newly developed semiconductor microstructures can now guide light and electrons resulting in important consequences for state-of-the-art electronic and photonic devices. This volume introduces a new generation of epitaxial microstructures. Special emphasis has been given to atomic control during growth and the interrelationship between the atomic arrangements and the properties of the structures.Key Features* Atomic-level control of semiconductor microstructures* Molecular beam epitaxy, metal-organic chemical vapor deposition* Quantum wells and quantum wires* Lasers, photon(IR)detectors, heterostructure transistors

  1. Introduction to semiconductor manufacturing technology

    CERN Document Server

    2012-01-01

    IC chip manufacturing processes, such as photolithography, etch, CVD, PVD, CMP, ion implantation, RTP, inspection, and metrology, are complex methods that draw upon many disciplines. [i]Introduction to Semiconductor Manufacturing Technologies, Second Edition[/i] thoroughly describes the complicated processes with minimal mathematics, chemistry, and physics; it covers advanced concepts while keeping the contents accessible to readers without advanced degrees. Designed as a textbook for college students, this book provides a realistic picture of the semiconductor industry and an in-depth discuss

  2. Wide band gap semiconductor templates

    Energy Technology Data Exchange (ETDEWEB)

    Arendt, Paul N. (Los Alamos, NM); Stan, Liliana (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM); DePaula, Raymond F. (Santa Fe, NM); Usov, Igor O. (Los Alamos, NM)

    2010-12-14

    The present invention relates to a thin film structure based on an epitaxial (111)-oriented rare earth-Group IVB oxide on the cubic (001) MgO terminated surface and the ion-beam-assisted deposition ("IBAD") techniques that are amendable to be over coated by semiconductors with hexagonal crystal structures. The IBAD magnesium oxide ("MgO") technology, in conjunction with certain template materials, is used to fabricate the desired thin film array. Similarly, IBAD MgO with appropriate template layers can be used for semiconductors with cubic type crystal structures.

  3. Modeling of semiconductor optical amplifiers

    DEFF Research Database (Denmark)

    Mørk, Jesper; Bischoff, Svend; Berg, Tommy Winther

    We discuss the modelling of semiconductor optical amplifiers with emphasis on their high-speed properties. Applications in linear amplification as well as ultrafast optical signal processing are reviewed. Finally, the possible role of quantum-dot based optical amplifiers is discussed.......We discuss the modelling of semiconductor optical amplifiers with emphasis on their high-speed properties. Applications in linear amplification as well as ultrafast optical signal processing are reviewed. Finally, the possible role of quantum-dot based optical amplifiers is discussed....

  4. Organic semiconductors in sensor applications

    CERN Document Server

    Malliaras, George; Owens, Róisín

    2008-01-01

    Organic semiconductors offer unique characteristics such as tunability of electronic properties via chemical synthesis, compatibility with mechanically flexible substrates, low-cost manufacturing, and facile integration with chemical and biological functionalities. These characteristics have prompted the application of organic semiconductors and their devices in physical, chemical, and biological sensors. This book covers this rapidly emerging field by discussing both optical and electrical sensor concepts. Novel transducers based on organic light-emitting diodes and organic thin-film transistors, as well as systems-on-a-chip architectures are presented. Functionalization techniques to enhance specificity are outlined, and models for the sensor response are described.

  5. Influence of phonons on semiconductor quantum emission

    Energy Technology Data Exchange (ETDEWEB)

    Feldtmann, Thomas

    2009-07-06

    A microscopic theory of interacting charge carriers, lattice vibrations, and light modes in semiconductor systems is presented. The theory is applied to study quantum dots and phonon-assisted luminescence in bulk semiconductors and heterostructures. (orig.)

  6. Fundamentals of semiconductors physics and materials properties

    CERN Document Server

    Yu, Peter Y

    2005-01-01

    Provides detailed explanations of the electronic, vibrational, transport, and optical properties of semiconductors. This textbook emphasizes understanding the physical properties of Si and similar tetrahedrally coordinated semiconductors and features an extensive collection of tables of material parameters, figures, and problems.

  7. Applications of semiconductor detectors to nuclear medicine

    CERN Document Server

    Bradford-Barber, H

    1999-01-01

    Progress in the development of semiconductor detectors is being applied to improving the resolution and imaging performance of nuclear medicine cameras. Nuclear medicine is briefly described. Efforts to develop semiconductor cameras for both planar and tomographic imaging are reviewed.

  8. Technology Support for High-Throughput Processing of Thin-Film CdTe PV Modules Annual Technical Report, Phase II

    Energy Technology Data Exchange (ETDEWEB)

    Rose, D.H.; Powell, R.C.; Karpov, V.; Grecu, D.; Jayamaha, U.; Dorer, G.L. (First Solar, L.L.C.)

    2001-02-05

    Results and conclusions from Phase II of a three-year subcontract are presented. The subcontract, entitled Technology Support for High-Throughput Processing of Thin-Film CdTe PV Modules, is First Solar's portion of the Thin-Film Photovoltaic Partnership Program. The research effort of this subcontract is divided into four areas of effort: (1) process and equipment development, (2) efficiency improvement, (3) characterization and analysis, and (4) environmental, health, and safety. As part of the process and equipment development effort, a new semiconductor deposition system with a throughput of 3 m2/min was completed, and a production line in a new 75,000 ft2 facility was started and is near completion. As part of the efficiency-improvement task, research was done on cells and modules with thin CdS and buffer layers as way to increase photocurrent with no loss in the other photovoltaic characteristics. A number of activities were part of the characterization and analysis task, including developing a new admittance spectroscopy system, with a range of 0.001 Hz to 100 kHz, to characterize cells. As part of the environmental, health, and safety task, the methanol-based CdCl2 process was replaced with aqueous-CdCl2. This change enabled the retention of a De Minimus level of emissions for the manufacturing plant, so no permitting is required.

  9. Research Leading to High Throughput Manufacturing of Thin-Film CdTe PV Modules: Annual Technical Report, September 2003-September 2004

    Energy Technology Data Exchange (ETDEWEB)

    Powell, R. C.

    2004-12-01

    First Solar is actively commercializing CdTe-based thin-film photovoltaics. During the past year, major additions of production capability have been completed, as well as process improvements to achieve higher throughput and efficiency and greater durability. This report presents the results of Phase II of the subcontract, entitled ''Research Leading to High Throughput Manufacturing of Thin-Film CdTe PV Modules.'' The subcontract supports several important aspects needed for high-volume manufacturing of high-efficiency modules, including exploration of large-area advanced front-contact window layers, improvements of the semiconductor deposition system, advancement in understanding of post-deposition processing steps and accelerated life testing methods, and progress in the environmental, health and safety programs. Work under this subcontract contributes to the overall manufacturing operation. During Phase II, average module efficiency (total area) on the production line was improved from 7.9% to 8.6% due primarily to process optimization. At the same, time production volume for commercial sales increased from 2.5 MW in 2003 to an estimated 6 MW in 2004. Much of the new 25 MW/yr production line has been qualified, and production volume is steadily increasing.

  10. Freescale Semiconductor Successfully Implements an Energy Management System

    Energy Technology Data Exchange (ETDEWEB)

    None

    2011-06-30

    Through the Superior Energy Performance (SEP) plant certification program, Freescale Semiconductor implemented projects at the company's Oak Hill Fab plant that reduced annual energy consumption by 28 million kilowatt hours (kWh) of electricity and 26,000 million British thermal units (Btu) of natural gas between 2006 and 2009, saving more than $2 million each year. The plant is now certified at the SEP silver level, and has a management system in place to proactively manage the facility's energy resources in the future.

  11. Annual Interviews

    CERN Multimedia

    Human Resources Department

    2005-01-01

    Annex II, page 1, Section 3 of the Administrative Circular no. 26 (Rev. 5) states that "The annual interview shall usually take place between 15 November of the reference year and 15 February of the following year." Following the meeting of the Executive Board on 7 December 2004 and the meeting of the Standing Concertation Committee on 19 January 2005, it has been decided, for the advancement exercise of 2005, to extend this period until 15 March 2005. Human Resources Department Tel. 73566

  12. Terahertz Nonlinear Optics in Semiconductors

    DEFF Research Database (Denmark)

    Turchinovich, Dmitry; Hvam, Jørn Märcher; Hoffmann, Matthias C.

    2013-01-01

    We demonstrate the nonlinear optical effects – selfphase modulation and saturable absorption of a single-cycle THz pulse in a semiconductor. Resulting from THz-induced modulation of Drude plasma, these nonlinear optical effects, in particular, lead to self-shortening and nonlinear spectral...

  13. Towards filament free semiconductor lasers

    DEFF Research Database (Denmark)

    McInerney, John; O'Brien, Peter; Skovgaard, Peter M. W.

    2000-01-01

    We outline physical models and simulations for suppression of self-focusing and filamentation in large aperture semiconductor lasers. The principal technical objective is to generate multi-watt CW or quasi-CW outputs with nearly diffraction limited beams, suitable for long distance free space...... propagation structures in lasers and amplifiers which suppress lateral reflections....

  14. Semiconductors for plasmonics and metamaterials

    DEFF Research Database (Denmark)

    Naik, G.V.; Boltasseva, Alexandra

    2010-01-01

    Plasmonics has conventionally been in the realm of metal-optics. However, conventional metals as plasmonic elements in the near-infrared (NIR) and visible spectral ranges suffer from problems such as large losses and incompatibility with semiconductor technology. Replacing metals with semiconduct...

  15. 2010 Defects in Semiconductors GRC

    Energy Technology Data Exchange (ETDEWEB)

    Shengbai Zhang

    2011-01-06

    Continuing its tradition of excellence, this Gordon Conference will focus on research at the forefront of the field of defects in semiconductors. The conference will have a strong emphasis on the control of defects during growth and processing, as well as an emphasis on the development of novel defect detection methods and first-principles defect theories. Electronic, magnetic, and optical properties of bulk, thin film, and nanoscale semiconductors will be discussed in detail. In contrast to many conferences, which tend to focus on specific semiconductors, this conference will deal with point and extended defects in a broad range of electronic materials. This approach has proved to be extremely fruitful for advancing fundamental understanding in emerging materials such as wide-band-gap semiconductors, oxides, sp{sup 2} carbon based-materials, and photovoltaic/solar cell materials, and in understanding important defect phenomena such as doping bottleneck in nanostructures and the diffusion of defects and impurities. The program consists of about twenty invited talks and a number of contributed poster sessions. The emphasis should be on work which has yet to be published. The large amount of discussion time provides an ideal forum for dealing with topics that are new and/or controversial.

  16. Atomistic Models of Amorphous Semiconductors

    NARCIS (Netherlands)

    Jarolimek, K.

    2011-01-01

    Crystalline silicon is probably the best studied material, widely used by the semiconductor industry. The subject of this thesis is an intriguing form of this element namely amorphous silicon. It can contain a varying amount of hydrogen and is denoted as a-Si:H. It completely lacks the neat long

  17. Basic semiconductor physics. 2. ed.

    Energy Technology Data Exchange (ETDEWEB)

    Hamaguchi, Chihiro [Osaka Univ., Suita (Japan). Dept. Electronic Engineering

    2010-07-01

    This book presents a detailed description of the basic semiconductor physics. The reader is assumed to have a basic command of mathematics and some elementary knowledge of solid state physics. The text covers a wide range of important phenomena in semiconductors, from the simple to the advanced. The reader can understand three different methods of energy band calculations, empirical pseudo-potential, k.p perturbation and tight-binding methods. The effective mass approximation and electron motion in a periodic potential, Boltzmann transport equation and deformation potentials used for full band Monte Carlo simulation are discussed. Experiments and theoretical analysis of cyclotron resonance are discussed in detail because the results are essential to the understanding of semiconductor physics. Optical and transport properties, magneto-transport, two dimensional electron gas transport (HEMT and MOSFET), and quantum transport are reviewed, explaining optical transition, electron phonon interactions, electron mobility. Recent progress in quantum structures such as two-dimensional electron gas, superlattices, quantum Hall effect, electron confinement and the Landauer formula are included. The Quantum Hall effect is presented with different models. In the second edition, the addition energy and electronic structure of a quantum dot (artificial atom) are explained with the help of Slater determinants. Also the physics of semiconductor Lasers is described in detail including Einstein coefficients, stimulated emission, spontaneous emission, laser gain, double heterostructures, blue Lasers, optical confinement, laser modes, strained quantum wells lasers which will give insight into the physics of various kinds of semiconductor lasers, in addition to the various processes of luminescence. (orig.)

  18. ASGRAD FY07 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Bradley R.; Riley, Brian J.; Crum, Jarrod V.; Sundaram, S. K.; Henager, Charles H.; Seifert, Carolyn E.; Van Ginhoven, Renee M.; Rockett, Angus; Aquino, Angel

    2008-05-06

    This is the annual project report for the ASGRAD project - Amorphous Semiconductors for Gamma Radiation Detection. We describe progress in the development of new materials for portable, room temperature, gammaradiation detection at Pacific Northwest National Laboratory. High Z, high resistivity, amorphous semiconductors are being designed for use as solid-state detectors at near ambient temperatures; their principles of operation are analogous to single-crystal semiconducting detectors. Compared to single crystals, amorphous semiconductors have the advantages of rapid, cost-effective, bulk-fabrication; nearnet-shape fabrication of complicated geometries; compositional flexibility; and greater electronic property control. The main disadvantage is reduced-charge carrier mobility. The focus of this project is to develop optimized amorphous semiconductor materials for gamma detection applications that leverage their material advantages while mitigating their limitations. During the second year of this project, several important milestones were accomplished. Major accomplishments were: (1) Significant processing - property and composition - property correlations were determined for Cd-Ge-As glasses; (2) Radiation response testing was successfully demonstrated on three different amorphous semiconductor materials (Cd-Ge-As, As-Se, and As-Se-Te systems) at ambient and near ambient temperatures; (3) Advanced, enabling Schottky contacts were developed for Cd-Ge-As compounds, this will allow these materials to perform at ambient temperatures; and (4) The collaborative working relationship developed with Prof. Angus Rockett at the University of Illinois at Urbana-Champaign (UIUC) has continued to grow, and they are credited with several of the materials characterization and contact development successes achieved this year. The development of Schottky barrier contacts in amorphous semiconductors by simply using different types of metal contacts is very significant. This is

  19. Mesoscale Modeling of Kinetic Phase Behaviors in Mg-B-H (Subcontract Report)

    Energy Technology Data Exchange (ETDEWEB)

    Yu, H. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Thornton, K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Wood, B. C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-10-13

    Storage of hydrogen on board vehicles is one of the critical enabling technologies for creating hydrogenfueled transportation systems that can reduce oil dependency and mitigate the long-term effects of fossil fuels on climate change. Stakeholders in developing hydrogen infrastructure are currently focused on highpressure storage at 350 bar and 700 bar, in part because no viable solid-phase storage material has emerged. Nevertheless, solid-state materials, including high-density hydrides, remain of interest because of their unique potential to meet all DOE targets and deliver hydrogen at lower pressures and higher on-board densities. A successful solution would significantly reduce costs and ensure the economic viability of a U.S. hydrogen infrastructure. The Mg(BH4)2-MgB2 system represents a highly promising solution because of its reasonable reaction enthalpy, high intrinsic capacity, and demonstrated reversibility, yet suffers from poor reaction kinetics. This subcontract aims to deliver a phase-field model for the kinetics of the evolution of the relevant phases within the Mg-B-H system during hydrogenation and dehydrogenation. This model will be used within a broader theory, synthesis, and characterization framework to study the properties of geometry-selected nanoparticles of pristine and doped MgB2/Mg(BH4)2 with two aims: (1) understand the intrinsic limitations in (de)hydrogenation; (2) devise strategies for improving thermodynamics and kinetics through nanostructuring.

  20. Semiconductor detectors in nuclear and particle physics

    Energy Technology Data Exchange (ETDEWEB)

    Rehak, P. [Brookhaven National Lab., Upton, NY (United States); Gatti, E. [Piazza Leonardo da Vinci 32, Milano (Italy)

    1992-12-31

    Semiconductor detectors for elementary particle physics and nuclear physics in the energy range above 1 GeV are briefly reviewed. In these two fields semiconductor detectors are used mainly for the precise position sensing. In a typical experiment, the position of a fast charged particle crossing a relatively thin semiconductor detector is measured. The position resolution achievable by semiconductor detectors is compared with the resolution achievable by gas filled position sensing detectors. Semiconductor detectors are divided into two groups: Classical semiconductor diode detectors and semiconductor memory detectors. Principles of the signal formation and the signal read-out for both groups of detectors are described. New developments of silicon detectors of both groups are reported.

  1. Semiconductor detectors in nuclear and particle physics

    Energy Technology Data Exchange (ETDEWEB)

    Rehak, P. [Brookhaven National Laboratory, Upton, New York 11973 (United States); Gatti, E. [Politecnico di Milano, Dipartimento di Elletronica e Informazione, Piazza Leondardo da Vinci 32, 20133 Milano (Italy)

    1995-07-10

    Semiconductor detectors for elementary particle physics and nuclear physics in the energy range above 1 GeV are briefly reviewed. In these two fields semiconductor detectors are used mainly for the precise position sensing. In a typical experiment, the position of a fast charged particle crossing a relatively thin semiconductor detector is measured. The position resolution achievable by semiconductor detectors is compared with the resolution achievable by gas filled position sensing detectors. Semiconductor detectors are divided into two groups; (i) classical semiconductor diode detectors and (ii) semiconductor memory detectors. Principles of the signal formation and the signal read-out for both groups of detectors are described. New developments of silicon detectors of both groups are reported. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

  2. Spectroscopic analysis of optoelectronic semiconductors

    CERN Document Server

    Jimenez, Juan

    2016-01-01

    This book deals with standard spectroscopic techniques which can be used to analyze semiconductor samples or devices, in both, bulk, micrometer and submicrometer scale. The book aims helping experimental physicists and engineers to choose the right analytical spectroscopic technique in order to get specific information about their specific demands. For this purpose, the techniques including technical details such as apparatus and probed sample region are described. More important, also the expected outcome from experiments is provided. This involves also the link to theory, that is not subject of this book, and the link to current experimental results in the literature which are presented in a review-like style. Many special spectroscopic techniques are introduced and their relationship to the standard techniques is revealed. Thus the book works also as a type of guide or reference book for people researching in optical spectroscopy of semiconductors.

  3. Catalysts, Protection Layers, and Semiconductors

    DEFF Research Database (Denmark)

    Chorkendorff, Ib

    2015-01-01

    acid or alkaline conditions. Since most relevant semiconductors are very prone to corrosion the advantage of using buried junctions and using protection layers offering shall be discussed [2-4]. Next we shall discuss the availability of various catalysts for being coupled to these protections layers...... and how their stability may be evaluated [5, 6]. Examples of half-cell reaction using protection layers for both cathode and anode will be discussed though some of recent examples under both alkaline and acidic conditions. Si is a very good low band gap semiconductor and by using TiO2 as a protection...... layer we can stabilize it for both H2 and O2 evolution [7, 8, 9, 10]. Notably NiOx promoted by iron is a material that is transparent, providing protection, and is a good catalyst for O2 evolution. We have also recently started searching for large band gap semicondutors like III-V based or pervoskite...

  4. Transversal light forces in semiconductors

    CERN Document Server

    Lindberg, M

    2003-01-01

    The transversal light force is a well established effect in atomic and molecular systems that are exposed to spatially inhomogeneous light fields. In this paper it is shown theoretically that in an excited semiconductor, containing an electron-hole plasma or excitons, a similar light force exists, if the semiconductor is exposed to an ultrashort spatially inhomogeneous light field. The analysis is based on the equations of motion for the Wigner distribution functions of charge carrier populations and interband polarizations. The results show that, while the light force on the electron-hole plasma or the excitons does exist, its effects on the kinetic behaviour of the electron-hole plasma or the excitons are different compared to the situation in an atomic or molecular system. A detailed analysis presented here traces this difference back to the principal differences between atoms and molecules on the one hand and electron-hole plasmas or excitons on the other hand.

  5. Semiconductor electrolyte photovoltaic energy converter

    Science.gov (United States)

    Anderson, W. W.; Anderson, L. B.

    1975-01-01

    Feasibility and practicality of a solar cell consisting of a semiconductor surface in contact with an electrolyte are evaluated. Basic components and processes are detailed for photovoltaic energy conversion at the surface of an n-type semiconductor in contact with an electrolyte which is oxidizing to conduction band electrons. Characteristics of single crystal CdS, GaAs, CdSe, CdTe and thin film CdS in contact with aqueous and methanol based electrolytes are studied and open circuit voltages are measured from Mott-Schottky plots and open circuit photo voltages. Quantum efficiencies for short circuit photo currents of a CdS crystal and a 20 micrometer film are shown together with electrical and photovoltaic properties. Highest photon irradiances are observed with the GaAs cell.

  6. Hypersonic modes in nanophononic semiconductors.

    Science.gov (United States)

    Hepplestone, S P; Srivastava, G P

    2008-09-05

    Frequency gaps and negative group velocities of hypersonic phonon modes in periodically arranged composite semiconductors are presented. Trends and criteria for phononic gaps are discussed using a variety of atomic-level theoretical approaches. From our calculations, the possibility of achieving semiconductor-based one-dimensional phononic structures is established. We present results of the location and size of gaps, as well as negative group velocities of phonon modes in such structures. In addition to reproducing the results of recent measurements of the locations of the band gaps in the nanosized Si/Si{0.4}Ge{0.6} superlattice, we show that such a system is a true one-dimensional hypersonic phononic crystal.

  7. Epitaxial Lateral Overgrowth of Semiconductors

    Science.gov (United States)

    Zytkiewicz, Zbigniew R.

    The state of the art and recent developments of lateral overgrowth of compound semiconductors are reviewed. First we focus on the mechanism of epitaxial lateral overgrowth (ELO) from the liquid phase, highlighting the phenomena that are crucial for growing high-quality layers with large aspect ratio. Epitaxy from the liquid phase has been chosen since the equilibrium growth techniques such as liquid-phase epitaxy (LPE) are the most suitable for lateral overgrowth. We then present numerous examples for which the defect filtration in the ELO procedure is very efficient and leads to significant progress in the development of high-performance semiconductor devices made of lattice-mismatched structures. Structural perfection of seams that appear when layers grown from neighboring seeds merge is also discussed. Next, we concentrate on strain commonly found in various ELO structures and arising due to the interaction of ELO layers with the mask. Its origin, and possible ways of its control, are presented. Then we show that the thermal strain in lattice-mismatched ELO structures can be relaxed by additional tilting of ELO wings while still preserving their high quality. Finally, recent progresses in the lateral overgrowth of semiconductors, including new mask materials and liquid-phase electroepitaxial growth on substrates coated by electrically conductive masks, are presented. New versions of the ELO technique from solution and from the vapor (growth from ridges and pendeo-epitaxy) are described and compared with standard ELO. A wide range of semiconductors, including III-V compounds grown from solution and vapor-grown GaN, are used to illustrate phenomena discussed. Very often, the similar behavior of various ELO structures reveals that the phenomena presented are not related to a specific group of compounds or their growth techniques, but have a much more general nature.

  8. Identification of defects in semiconductors

    CERN Document Server

    Stavola, Michael; Weber, Eicke R; Stavola, Michael

    1998-01-01

    Since its inception in 1966, the series of numbered volumes known as Semiconductors and Semimetals has distinguished itself through the careful selection of well-known authors, editors, and contributors.The"Willardson and Beer"Series, as it is widely known, has succeeded in publishing numerous landmark volumes and chapters. Not only did many of these volumes make an impact at the time of their publication, but they continue to be well-cited years after their original release. Recently, Professor Eicke R. Weber of the University of California at Berkeley joined as a co-editor of the series. Professor Weber, a well-known expert in the field of semiconductor materials, will further contribute to continuing the series' tradition of publishing timely, highly relevant, and long-impacting volumes. Some of the recent volumes, such as Hydrogen in Semiconductors, Imperfections in III/V Materials, Epitaxial Microstructures, High-Speed Heterostructure Devices,Oxygen in Silicon, and others promise indeed that this traditi...

  9. Ballistic superconductivity in semiconductor nanowires.

    Science.gov (United States)

    Zhang, Hao; Gül, Önder; Conesa-Boj, Sonia; Nowak, Michał P; Wimmer, Michael; Zuo, Kun; Mourik, Vincent; de Vries, Folkert K; van Veen, Jasper; de Moor, Michiel W A; Bommer, Jouri D S; van Woerkom, David J; Car, Diana; Plissard, Sébastien R; Bakkers, Erik P A M; Quintero-Pérez, Marina; Cassidy, Maja C; Koelling, Sebastian; Goswami, Srijit; Watanabe, Kenji; Taniguchi, Takashi; Kouwenhoven, Leo P

    2017-07-06

    Semiconductor nanowires have opened new research avenues in quantum transport owing to their confined geometry and electrostatic tunability. They have offered an exceptional testbed for superconductivity, leading to the realization of hybrid systems combining the macroscopic quantum properties of superconductors with the possibility to control charges down to a single electron. These advances brought semiconductor nanowires to the forefront of efforts to realize topological superconductivity and Majorana modes. A prime challenge to benefit from the topological properties of Majoranas is to reduce the disorder in hybrid nanowire devices. Here we show ballistic superconductivity in InSb semiconductor nanowires. Our structural and chemical analyses demonstrate a high-quality interface between the nanowire and a NbTiN superconductor that enables ballistic transport. This is manifested by a quantized conductance for normal carriers, a strongly enhanced conductance for Andreev-reflecting carriers, and an induced hard gap with a significantly reduced density of states. These results pave the way for disorder-free Majorana devices.

  10. Research Leading to High Throughput Processing of Thin-Film CdTe PV Module: Phase I Annual Report, October 2003 (Revised)

    Energy Technology Data Exchange (ETDEWEB)

    Powell, R. C.; Meyers, P. V.

    2004-02-01

    Work under this subcontract contributes to the overall manufacturing operation. During Phase I, average module efficiency on the line was improved from 7.1% to 7.9%, due primarily to increased photocurrent resulting from a decrease in CdS thickness. At the same time, production volume for commercial sale increased from 1.5 to 2.5 MW/yr. First Solar is committed to commercializing CdTe-based thin-film photovoltaics. This commercialization effort includes a major addition of floor space and equipment, as well as process improvements to achieve higher efficiency and greater durability. This report presents the results of Phase I of the subcontract entitled''Research Leading to High Throughput Processing of Thin-Film CdTe PV Modules.'' The subcontract supports several important aspects needed to begin high-volume manufacturing, including further development of the semiconductor deposition reactor, advancement of accelerated life testing methods and understanding, and improvements to th e environmental, health, and safety programs. Progress in the development of the semiconductor deposition reactor was made in several areas. First, a new style of vapor transport deposition distributor with simpler operational behavior and the potential for improved cross-web uniformity was demonstrated. Second, an improved CdS feed system that will improve down-web uniformity was developed. Third, the core of a numerical model of fluid and heat flow within the distributor was developed, including flow in a 3-component gas system at high temperature and low pressure and particle sublimation.

  11. NREL Photovoltaic Program FY 1995 annual report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-06-01

    This report summarizes the in-house and subcontracted R&D activities from Oct. 1994 through Sept. 1995; their objectives are to conduct basic, applied, and engineering research, manage subcontracted R&D projects, perform research complementary to subcontracted work, develop and maintain state-of-the-art measurement and device capabilities, develop PV manufacturing technology and modules, transfer results to industry, and evolve viable partnerships for PV systems and market development. The research activities are grouped into 5 sections: crystalline Si and advanced devices, thin-film PV, PV manufacturing, PV module and system performance and engineering, and PV applications and market development.

  12. 75 FR 49526 - Freescale Semiconductor, Inc., Technical Information Center, Tempe, AZ; Freescale Semiconductor...

    Science.gov (United States)

    2010-08-13

    ... Employment and Training Administration Freescale Semiconductor, Inc., Technical Information Center, Tempe, AZ; Freescale Semiconductor, Inc., Technical Information Center, Woburn, MA; Amended Certification Regarding... to Apply for Worker Adjustment Assistance on October 1, 2009, applicable to workers of Freescale...

  13. Electronic properties of semiconductor surfaces and metal/semiconductor interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Tallarida, M.

    2005-05-15

    This thesis reports investigations of the electronic properties of a semiconductor surface (silicon carbide), a reactive metal/semiconductor interface (manganese/silicon) and a non-reactive metal/semiconductor interface (aluminum-magnesium alloy/silicon). The (2 x 1) reconstruction of the 6H-SiC(0001) surface has been obtained by cleaving the sample along the (0001) direction. This reconstruction has not been observed up to now for this compound, and has been compared with those of similar elemental semiconductors of the fourth group of the periodic table. This comparison has been carried out by making use of photoemission spectroscopy, analyzing the core level shifts of both Si 2p and C 1s core levels in terms of charge transfer between atoms of both elements and in different chemical environments. From this comparison, a difference between the reconstruction on the Si-terminated and the C-terminated surface was established, due to the ionic nature of the Si-C bond. The growth of manganese films on Si(111) in the 1-5 ML thickness range has been studied by means of LEED, STM and photoemission spectroscopy. By the complementary use of these surface science techniques, two different phases have been observed for two thickness regimes (<1 ML and >1 ML), which exhibit a different electronic character. The two reconstructions, the (1 x 1)-phase and the ({radical}3 x {radical}3)R30 -phase, are due to silicide formation, as observed in core level spectroscopy. The growth proceeds via island formation in the monolayer regime, while the thicker films show flat layers interrupted by deep holes. On the basis of STM investigations, this growth mode has been attributed to strain due to lattice mismatch between the substrate and the silicide. Co-deposition of Al and Mg onto a Si(111) substrate at low temperature (100K) resulted in the formation of thin alloy films. By varying the relative content of both elements, the thin films exhibited different electronic properties

  14. Emission and Absorption Entropy Generation in Semiconductors

    OpenAIRE

    Reck, Kasper; Varpula, Aapo; Prunnila, Mika; Hansen, Ole

    2013-01-01

    While emission and absorption entropy generation is well known in black bodies, it has not previously been studied in semiconductors, even though semiconductors are widely used for solar light absorption in modern solar cells [1]. We present an analysis of the entropy generation in semiconductor materials due to emission and absorption of electromagnetic radiation. It is shown that the emission and absorption entropy generation reduces the fundamental limit on the efficiency of any semiconduc...

  15. Hybridization at superconductor-semiconductor interfaces

    OpenAIRE

    Mikkelsen, August E. G.; Kotetes, Panagiotis; Krogstrup, Peter; Flensberg, Karsten

    2018-01-01

    Hybrid superconductor-semiconductor devices are currently one of the most promising platforms for realizing Majorana zero modes. We address the role of band bending and superconductor-semiconductor hybridization in such devices by analyzing a gated single Al-InAs interface using a self-consistent Schroedinger-Poisson approach. Our numerical analysis shows that the band bending leads to an interface quantum well, which localizes the charge in the system near the superconductor-semiconductor in...

  16. Semiconductor power devices physics, characteristics, reliability

    CERN Document Server

    Lutz, Josef; Scheuermann, Uwe; De Doncker, Rik

    2011-01-01

    Semiconductor power devices are the heart of power electronics. They determine the performance of power converters and allow topologies with high efficiency. Semiconductor properties, pn-junctions and the physical phenomena for understanding power devices are discussed in depth. Working principles of state-of-the-art power diodes, thyristors, MOSFETs and IGBTs are explained in detail, as well as key aspects of semiconductor device production technology. In practice, not only the semiconductor, but also the thermal and mechanical properties of packaging and interconnection technologies are esse

  17. Toward a national semiconductor strategy, volume 1

    Science.gov (United States)

    1991-02-01

    Updated here are key market data showing trends in the U.S. semiconductor industry's world market position. New information is given on three emerging semiconductor-based technologies: broadband communications, advanced display systems, and intelligent vehicles and highways. These are examples of important, high-volume markets that will consume significant numbers of semiconductor components and that must be addressed in a national semiconductor strategy. New recommendations and a summary of all Committee recommendations to date are given as well as a summary of comments received at a public forum held in Silicon Valley in may 1990.

  18. Microradiography with Semiconductor Pixel Detectors

    Science.gov (United States)

    Jakubek, Jan; Cejnarova, Andrea; Dammer, Jiří; Holý, Tomáš; Platkevič, Michal; Pospíšil, Stanislav; Vavřík, Daniel; Vykydal, Zdeněk

    2007-11-01

    High resolution radiography (with X-rays, neutrons, heavy charged particles, …) often exploited also in tomographic mode to provide 3D images stands as a powerful imaging technique for instant and nondestructive visualization of fine internal structure of objects. Novel types of semiconductor single particle counting pixel detectors offer many advantages for radiation imaging: high detection efficiency, energy discrimination or direct energy measurement, noiseless digital integration (counting), high frame rate and virtually unlimited dynamic range. This article shows the application and potential of pixel detectors (such as Medipix2 or TimePix) in different fields of radiation imaging.

  19. Optoelectronic properties of semiconductor nanostructures

    Science.gov (United States)

    Maher, Kristin Nicole

    Semiconductor nanostructures have unique optical and electronic properties that have inspired research into their technological applications and basic science. This thesis presents approaches to the fabrication and characterization of optoelectronic devices incorporating individual semiconductor nanostructures. Nanowires of the II-VI semiconductors CdSe and CdS were synthesized using nanoparticle-catalysed solution-liquid-solid growth. Single-component nanowires and heterostructure nanowires with axial compositional modulation were generated using this method. Individual nanowires and nanocrystals were then incorporated into devices with a three-terminal field-effect transistor geometry. An experimental platform was developed which allows for simultaneous electrical characterization of devices and measurement of their optical properties. This setup enables the measurement of spatially and spectrally resolved electroluminescence (EL) and photoluminescence (PL) from individual nanostructures and nanostructure devices. It also allows the measurement of photon coincidence histograms for emitted light and the acquisition of photocurrent images via laser scanning microscopy. Electroluminescence was observed from individual CdSe nanocrystals contacted by gold electrodes. Concomitant transport measurements at low temperature showed clear evidence of Coulomb blockade at low bias voltage, with light only emitted from devices exhibiting asymmetric tunnel couplings between the nanocrystal and electrodes. Combined analyses of the data indicate that the resistances of the tunnel barriers are bias voltage dependent and that light emission results from the inelastic scattering of tunneling electrons. Three-terminal devices incorporating individual CdSe nanoNvires exhibited EL localized near the positively-biased electrode. Characterization of these devices by scanning photocurrent microscopy (SPCM) and Kelvin probe microscopy (KPM) indicates that while there are n-type Schottky

  20. Optic probe for semiconductor characterization

    Science.gov (United States)

    Sopori, Bhushan L [Denver, CO; Hambarian, Artak [Yerevan, AM

    2008-09-02

    Described herein is an optical probe (120) for use in characterizing surface defects in wafers, such as semiconductor wafers. The optical probe (120) detects laser light reflected from the surface (124) of the wafer (106) within various ranges of angles. Characteristics of defects in the surface (124) of the wafer (106) are determined based on the amount of reflected laser light detected in each of the ranges of angles. Additionally, a wafer characterization system (100) is described that includes the described optical probe (120).

  1. Trace analysis of semiconductor materials

    CERN Document Server

    Cali, J Paul; Gordon, L

    1964-01-01

    Trace Analysis of Semiconductor Materials is a guidebook concerned with procedures of ultra-trace analysis. This book discusses six distinct techniques of trace analysis. These techniques are the most common and can be applied to various problems compared to other methods. Each of the four chapters basically includes an introduction to the principles and general statements. The theoretical basis for the technique involved is then briefly discussed. Practical applications of the techniques and the different instrumentations are explained. Then, the applications to trace analysis as pertaining

  2. Electronic Properties of Semiconductor Interfaces.

    Science.gov (United States)

    1983-02-01

    AD-A130 745 ELECTRONIC PROPERTIES OF SEMICONDUCTOR INTERFACES(U) /; UNIVERSIDAD AUfONOMA DE MADRID (SPAIN) DEPT DE FISICA DEL ESTADO SOLIDO F FLORES...Estado Solido 6.11.02A Universidad Autonoma Cantoblanco, Madrid 34. Spain 1T161102BH57-03 11. CONTROLLING OFFICE NAME AND ADDRESS 12. REPORT DATE...different supe4layeru formed by the superlayers (0,1), (2,3), (4,5),... and so on. Note that the number of super - layers defined inside each 6upettayer

  3. Processing of insulators and semiconductors

    Science.gov (United States)

    Quick, Nathaniel R.; Joshi, Pooran C.; Duty, Chad Edward; Jellison, Jr., Gerald Earle; Angelini, Joseph Attilio

    2015-06-16

    A method is disclosed for processing an insulator material or a semiconductor material. The method includes pulsing a plasma lamp onto the material to diffuse a doping substance into the material, to activate the doping substance in the material or to metallize a large area region of the material. The method may further include pulsing a laser onto a selected region of the material to diffuse a doping substance into the material, to activate the doping substance in the material or to metallize a selected region of the material.

  4. Semiconductor-Based Nanotechnology Applications

    Science.gov (United States)

    2012-11-07

    as SnO2 , ZnO, and CeO2, reported in 40 refereed research papers. In this ARO project, studies on ultra small particles of these oxides with...semiconductors such as SnO2 , ZnO, and CeO2, reported in 40 refereed research papers. In this ARO project, studies on ultra small particles of these oxides...ferromagnetism. Thin film structures using Co doped SnO2 were fabricated and studied their usefulness in device applications. NP of semiconducting oxides such

  5. Dual modulation of semiconductor lasers

    Energy Technology Data Exchange (ETDEWEB)

    Gorfinkel, V.B. [Univ. of Kassel (Germany); Luryi, S. [AT and T Bell Labs., Murray Hill, NJ (United States)

    1994-12-31

    Large signal analysis of dual modulation of semiconductor lasers (by a simultaneous high-frequency control of the pumping current I and an additional intrinsic parameter) shows that the method allows suppressing the relaxation oscillations for an arbitrary shape of the pumping current signal I (t). Because of that, the rate of information coding can be enhanced to about 80 Gbit/sec. Moreover, the authors demonstrate that dual modulation allows to maintain a linear relationship between I (t) and the output optical power in a wide frequency band.

  6. Suitability of integrated protection diodes from diverse semiconductor technologies

    NARCIS (Netherlands)

    van Wanum, Maurice; Lebouille, Tom; Visser, Guido; van Vliet, Frank Edward

    2009-01-01

    Abstract In this article diodes from three different semiconductor technologies are compared based on their suitability to protect a receiver. The semiconductor materials involved are silicon, gallium arsenide and gallium nitride. The diodes in the diverse semiconductor technologies themselves are

  7. Semiconductor nanostructures for artificial photosynthesis

    Science.gov (United States)

    Yang, Peidong

    2012-02-01

    Nanowires, with their unique capability to bridge the nanoscopic and macroscopic worlds, have already been demonstrated as important materials for different energy conversion. One emerging and exciting direction is their application for solar to fuel conversion. The generation of fuels by the direct conversion of solar energy in a fully integrated system is an attractive goal, but no such system has been demonstrated that shows the required efficiency, is sufficiently durable, or can be manufactured at reasonable cost. One of the most critical issues in solar water splitting is the development of a suitable photoanode with high efficiency and long-term durability in an aqueous environment. Semiconductor nanowires represent an important class of nanostructure building block for direct solar-to-fuel application because of their high surface area, tunable bandgap and efficient charge transport and collection. Nanowires can be readily designed and synthesized to deterministically incorporate heterojunctions with improved light absorption, charge separation and vectorial transport. Meanwhile, it is also possible to selectively decorate different oxidation or reduction catalysts onto specific segments of the nanowires to mimic the compartmentalized reactions in natural photosynthesis. In this talk, I will highlight several recent examples in this lab using semiconductor nanowires and their heterostructures for the purpose of direct solar water splitting.

  8. Semiconductor X-ray detectors

    CERN Document Server

    Lowe, Barrie Glyn

    2014-01-01

    Identifying and measuring the elemental x-rays released when materials are examined with particles (electrons, protons, alpha particles, etc.) or photons (x-rays and gamma rays) is still considered to be the primary analytical technique for routine and non-destructive materials analysis. The Lithium Drifted Silicon (Si(Li)) X-Ray Detector, with its good resolution and peak to background, pioneered this type of analysis on electron microscopes, x-ray fluorescence instruments, and radioactive source- and accelerator-based excitation systems. Although rapid progress in Silicon Drift Detectors (SDDs), Charge Coupled Devices (CCDs), and Compound Semiconductor Detectors, including renewed interest in alternative materials such as CdZnTe and diamond, has made the Si(Li) X-Ray Detector nearly obsolete, the device serves as a useful benchmark and still is used in special instances where its large, sensitive depth is essential. Semiconductor X-Ray Detectors focuses on the history and development of Si(Li) X-Ray Detect...

  9. Terahertz semiconductor-heterostructure laser.

    Science.gov (United States)

    Köhler, Rüdeger; Tredicucci, Alessandro; Beltram, Fabio; Beere, Harvey E; Linfield, Edmund H; Davies, A Giles; Ritchie, David A; Iotti, Rita C; Rossi, Fausto

    2002-05-09

    Semiconductor devices have become indispensable for generating electromagnetic radiation in everyday applications. Visible and infrared diode lasers are at the core of information technology, and at the other end of the spectrum, microwave and radio-frequency emitters enable wireless communications. But the terahertz region (1-10 THz; 1 THz = 10(12) Hz) between these ranges has remained largely underdeveloped, despite the identification of various possible applications--for example, chemical detection, astronomy and medical imaging. Progress in this area has been hampered by the lack of compact, low-consumption, solid-state terahertz sources. Here we report a monolithic terahertz injection laser that is based on interminiband transitions in the conduction band of a semiconductor (GaAs/AlGaAs) heterostructure. The prototype demonstrated emits a single mode at 4.4 THz, and already shows high output powers of more than 2 mW with low threshold current densities of about a few hundred A cm(-2) up to 50 K. These results are very promising for extending the present laser concept to continuous-wave and high-temperature operation, which would lead to implementation in practical photonic systems.

  10. 2 CFR 801.220 - What contracts and subcontracts, in addition to those listed in 2 CFR 180.220, are covered...

    Science.gov (United States)

    2010-01-01

    ... 2 Grants and Agreements 1 2010-01-01 2010-01-01 false What contracts and subcontracts, in addition to those listed in 2 CFR 180.220, are covered transactions? 801.220 Section 801.220 Grants and Agreements Federal Agency Regulations for Grants and Agreements DEPARTMENT OF VETERANS AFFAIRS NONPROCUREMENT...

  11. Modeling of semiconductor nanostructures and semiconductor-electrolyte interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Birner, Stefan

    2011-11-15

    The main objective of Part I is to give an overview of some of the methods that have been implemented into the nextnano{sup 3} software. Examples are discussed that give insight into doping, strain and mobility. Applications of the single-band Schroedinger equation include three-dimensional superlattices, and a qubit that is manipulated by a magnetic field. Results of the multi-band k.p method are presented for HgTe-CdTe and InAs-GaSb superlattices, and for a SiGe-Si quantum cascade structure. Particular focus is put on a detailed description of the contact block reduction (CBR) method that has been developed within our research group. By means of this approach, quantum transport in the ballistic limit in one, two and three dimensions can be calculated. I provide a very detailed description of the algorithm and present several well documented examples that highlight the key points of this method. Calculating quantum transport in three dimensions is a very challenging task where computationally efficient algorithms - apart from the CBR method - are not available yet. Part II describes the methods that I have implemented into the nextnano{sup 3} software for calculating systems that consist of a combination of semiconductor materials and liquids. These biosensors have a solid-electrolyte interface, and the charges in the solid and in the electrolyte are coupled to each other through the Poisson-Boltzmann equation. I apply this model to a silicon based protein sensor, where I solve the Schroedinger equation together with the Poisson-Boltzmann equation self-consistently, and compare theoretical results with experiment. Furthermore, I have developed a novel approach to model the charge density profiles at semiconductor-electrolyte interfaces that allows us to distinguish hydrophobic and hydrophilic interfaces. Our approach extends previous work where ion specific potentials of mean force describe the distribution of ion species at the interface. I apply this new model

  12. Novel room temperature ferromagnetic semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Amita [KTH Royal Inst. of Technology, Stockholm (Sweden)

    2004-06-01

    Today's information world, bits of data are processed by semiconductor chips, and stored in the magnetic disk drives. But tomorrow's information technology may see magnetism (spin) and semiconductivity (charge) combined in one 'spintronic' device that exploits both charge and 'spin' to carry data (the best of two worlds). Spintronic devices such as spin valve transistors, spin light emitting diodes, non-volatile memory, logic devices, optical isolators and ultra-fast optical switches are some of the areas of interest for introducing the ferromagnetic properties at room temperature in a semiconductor to make it multifunctional. The potential advantages of such spintronic devices will be higher speed, greater efficiency, and better stability at a reduced power consumption. This Thesis contains two main topics: In-depth understanding of magnetism in Mn doped ZnO, and our search and identification of at least six new above room temperature ferromagnetic semiconductors. Both complex doped ZnO based new materials, as well as a number of nonoxides like phosphides, and sulfides suitably doped with Mn or Cu are shown to give rise to ferromagnetism above room temperature. Some of the highlights of this work are discovery of room temperature ferromagnetism in: (1) ZnO:Mn (paper in Nature Materials, Oct issue, 2003); (2) ZnO doped with Cu (containing no magnetic elements in it); (3) GaP doped with Cu (again containing no magnetic elements in it); (4) Enhancement of Magnetization by Cu co-doping in ZnO:Mn; (5) CdS doped with Mn, and a few others not reported in this thesis. We discuss in detail the first observation of ferromagnetism above room temperature in the form of powder, bulk pellets, in 2-3 mu-m thick transparent pulsed laser deposited films of the Mn (<4 at. percent) doped ZnO. High-resolution transmission electron microscopy (HRTEM) and electron energy loss spectroscopy (EELS) spectra recorded from 2 to 200nm areas showed homogeneous

  13. New semiconductor materials for magnetoelectronics at room ...

    Indian Academy of Sciences (India)

    Most of the semiconductor materials are diamagnetic by nature and therefore cannot take active part in the operation of the magneto electronic devices. In order to enable them to be useful for such devices a recent effort has been made to develop diluted magnetic semiconductors (DMS) in which small quantity of magnetic ...

  14. Epitaxy of semiconductor-superconductor nanowires

    DEFF Research Database (Denmark)

    Krogstrup, P.; Ziino, N.L.B.; Chang, W.

    2015-01-01

    Controlling the properties of semiconductor/metal interfaces is a powerful method for designing functionality and improving the performance of electrical devices. Recently semiconductor/superconductor hybrids have appeared as an important example where the atomic scale uniformity of the interface...

  15. Semiconductor saturable absorbers for ultrafast terahertz signals

    DEFF Research Database (Denmark)

    Hoffmann, Matthias C.; Turchinovich, Dmitry

    2010-01-01

    We demonstrate saturable absorber behavior of n-type semiconductors GaAs, GaP, and Ge in the terahertz THz frequency range at room temperature using nonlinear THz spectroscopy. The saturation mechanism is based on a decrease in electron conductivity of semiconductors at high electron momentum...

  16. Semiconductor composition containing iron, dysprosium, and terbium

    Energy Technology Data Exchange (ETDEWEB)

    Pooser, Raphael C.; Lawrie, Benjamin J.; Baddorf, Arthur P.; Malasi, Abhinav; Taz, Humaira; Farah, Annettee E.; Kalyanaraman, Ramakrishnan; Duscher, Gerd Josef Mansfred; Patel, Maulik K.

    2017-09-26

    An amorphous semiconductor composition includes 1 to 70 atomic percent iron, 15 to 65 atomic percent dysprosium, 15 to 35 atomic percent terbium, balance X, wherein X is at least one of an oxidizing element and a reducing element. The composition has an essentially amorphous microstructure, an optical transmittance of at least 50% in at least the visible spectrum and semiconductor electrical properties.

  17. Packaging of high power semiconductor lasers

    CERN Document Server

    Liu, Xingsheng; Xiong, Lingling; Liu, Hui

    2014-01-01

    This book introduces high power semiconductor laser packaging design. The characteristics and challenges of the design and various packaging, processing, and testing techniques are detailed by the authors. New technologies, in particular thermal technologies, current applications, and trends in high power semiconductor laser packaging are described at length and assessed.

  18. neutron-Induced Failures in semiconductor Devices

    Energy Technology Data Exchange (ETDEWEB)

    Wender, Stephen Arthur [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-03-13

    Single Event Effects are a very significant failure mode in modern semiconductor devices that may limit their reliability. Accelerated testing is important for semiconductor industry. Considerable more work is needed in this field to mitigate the problem. Mitigation of this problem will probably come from Physicists and Electrical Engineers working together

  19. Molecular semiconductors photoelectrical properties and solar cells

    CERN Document Server

    Rees, Ch

    1985-01-01

    During the past thirty years considerable efforts have been made to design the synthesis and the study of molecular semiconductors. Molecular semiconductors - and more generally molecular materials - involve interactions between individual subunits which can be separately synthesized. Organic and metallo-organic derivatives are the basis of most of the molecular materials. A survey of the literature on molecular semiconductors leaves one rather confused. It does seem to be very difficult to correlate the molecular structure of these semiconductors with their experimental electrical properties. For inorganic materials a simple definition delimits a fairly homogeneous family. If an inorganic material has a conductivity intermediate between that of an 12 1 1 3 1 1 insulator « 10- n- cm- ) and that of a metal (> 10 n- cm- ), then it is a semiconductor and will exhibit the characteristic properties of this family, such as junction formation, photoconductivity, and the photovoltaic effect. For molecular compounds,...

  20. Physics of semiconductor devices (2nd edition)

    Energy Technology Data Exchange (ETDEWEB)

    Sze, S.M.

    1981-01-01

    A resume is presented regarding the physics and properties of semiconductors, taking into account aspects of crystal structure, the energy bands, the carrier concentration at thermal equilibrium, carrier transport phenomena, basic equations for semiconductor device operation, and phonon spectra and optical, thermal, and high-field properties of semiconductors. The bipolar devices considered include the p-n junction diode, the bipolar transistor, and thyristors. Unipolar devices are discussed, taking into account metal-semiconductor contacts, JFET and MESFET, the MIS diode and CCD, and MOSFET. A description is provided of special microwave devices, giving attention to tunnel devices, IMPATT and related transit-time diodes, and transferred-electron devices. Photonic devices investigated include LED and semiconductor lasers, photodetectors, and solar cells.

  1. Device Physics of Narrow Gap Semiconductors

    CERN Document Server

    Chu, Junhao

    2010-01-01

    Narrow gap semiconductors obey the general rules of semiconductor science, but often exhibit extreme features of these rules because of the same properties that produce their narrow gaps. Consequently these materials provide sensitive tests of theory, and the opportunity for the design of innovative devices. Narrow gap semiconductors are the most important materials for the preparation of advanced modern infrared systems. Device Physics of Narrow Gap Semiconductors offers descriptions of the materials science and device physics of these unique materials. Topics covered include impurities and defects, recombination mechanisms, surface and interface properties, and the properties of low dimensional systems for infrared applications. This book will help readers to understand not only the semiconductor physics and materials science, but also how they relate to advanced opto-electronic devices. The last chapter applies the understanding of device physics to photoconductive detectors, photovoltaic infrared detector...

  2. Manipulating semiconductor colloidal stability through doping.

    Science.gov (United States)

    Fleharty, Mark E; van Swol, Frank; Petsev, Dimiter N

    2014-10-10

    The interface between a doped semiconductor material and electrolyte solution is of considerable fundamental interest, and is relevant to systems of practical importance. Both adjacent domains contain mobile charges, which respond to potential variations. This is exploited to design electronic and optoelectronic sensors, and other enabling semiconductor colloidal materials. We show that the charge mobility in both phases leads to a new type of interaction between semiconductor colloids suspended in aqueous electrolyte solutions. This interaction is due to the electrostatic response of the semiconductor interior to disturbances in the external field upon the approach of two particles. The electrostatic repulsion between two charged colloids is reduced from the one governed by the charged groups present at the particles surfaces. This type of interaction is unique to semiconductor particles and may have a substantial effect on the suspension dynamics and stability.

  3. An Industrial-Based Consortium to Develop Premium Carbon Products from Coal, Annual Progress Report, October 1, 2005 through September 30, 2006

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Bruce G

    2006-09-29

    Since 1998, The Pennsylvania State University has been successfully managing the Consortium for Premium Carbon Products from Coal (CPCPC), which is a vehicle for industry-driven research on the promotion, development, and transfer of innovative technology on premium carbon produces from coal to the U.S. industry. The CPCPC is an initiative being led by Penn State, its co-charter member West Virginia University (WVU), and the U.S. Department of Energy's (DOE) National Energy Technology Laboratory (NETL), who also provides the base funding for the program, with Penn State responsible for consortium management. CPCPC began in 1998 under DOE Cooperative Agreement No. DE-FC26-98FT40350. This agreement ended November 2004 but the CPCPC activity has continued under the present cooperative agreement, No. DE-FC26-03NT41874, which started October 1, 2003. The objective of the second agreement is to continue the successful operation of the CPCPC. The CPCPC has enjoyed tremendous success with its organizational structure, that includes Penn State and WVU as charter members, numerous industrial affiliate members, and strategic university affiliate members together with NETL, forming a vibrant and creative team for innovative research in the area of transforming coal to carbon products. The key aspect of CPCPC is its industry-led council that selects proposals submitted by CPCPC members to ensure CPCPC target areas have strong industrial support. Base funding for the selected projects is provided by NETL with matching funds from industry. At the annual funding meeting held in October 2003, ten projects were selected for funding. Subcontracts were let from Penn State to the subcontractors on March 1, 2004. Nine of the ten 2004 projects were completed during the previous annual reporting period and their final reports were submitted with the previous annual report (i.e., 10/01/04-09/30/05). The final report for the remaining project, which was submitted during this reporting

  4. Electrons in metals and semiconductors

    CERN Document Server

    Chambers, R G

    1990-01-01

    This book is part of a series of short texts for students, scientists and engineers who seek to broaden their knowledge of the physics underlying modern technology. This text aims to provide a review of the fundamental physics and recent developments in the area of solid-state physics. The book contains a range of topics discussing metals and semiconductors with references to treatises and the primary literature to facilitate further study. The book is intended to be useful to those engaged in research and development, who require a summary of a topic in physics or a new application of physical principles in their work. Many of the the texts will also be useful for final year undergraduate and postgraduate students.

  5. Semirelativity in semiconductors: a review

    Science.gov (United States)

    Zawadzki, Wlodek

    2017-09-01

    An analogy between behavior of electrons in narrow-gap semiconductors (NGS) and relativistic electrons in vacuum is reviewed. Energy band structures \\varepsilon ≤ft(\\mathbf{k}\\right) are considered for various NGS materials and their correspondence to the energy-momentum relation in special relativity is emphasized. It is indicated that special relativity for vacuum is analogous to a two-band \\mathbf{k}\\centerdot \\mathbf{p} description for NGS. The maximum electron velocity in NGS is u≃ 1× {{10}8}~\\text{cm}~{{\\text{s}}-1} , which corresponds to the light velocity in vacuum. An effective mass of charge carriers in semiconductors is introduced, relating their velocity to quasimomentum and it is shown that this mass depends on electron energy (or velocity) in a way similar to the mass of free relativistic electrons. In \\text{H}{{\\text{g}}1-x}\\text{C}{{\\text{d}}x}\\text{Te} alloys one can reach vanishing energy gap at which electrons and light holes become three-dimensional massless Dirac fermions. A wavelength {λz} is defined for NGS, in analogy to the Compton wavelength in relativistic quantum mechanics. It is estimated that {λz} is on the order of tens of Angstroms in typical semiconducting materials which is experimentally confirmed in tunneling experiments on energy dispersion in the forbidden gap. Statistical properties of the electron gas in NGS are calculated and their similarity is demonstrated to those of the Juttner gas of relativistic particles. Interband electron tunneling in NGS is described and shown to be in close analogy to the predicted but unobserved tunneling between negative and positive energies resulting from the Dirac equation for free electrons. It is demonstrated that the relativistic analogy holds for orbital and spin properties of electrons in the presence of an external magnetic field. In particular, it is shown that the spin magnetic moment of both NGS electrons and relativistic electrons approaches zero with increasing

  6. High throughput semiconductor deposition system

    Energy Technology Data Exchange (ETDEWEB)

    Young, David L.; Ptak, Aaron Joseph; Kuech, Thomas F.; Schulte, Kevin; Simon, John D.

    2017-11-21

    A reactor for growing or depositing semiconductor films or devices. The reactor may be designed for inline production of III-V materials grown by hydride vapor phase epitaxy (HVPE). The operating principles of the HVPE reactor can be used to provide a completely or partially inline reactor for many different materials. An exemplary design of the reactor is shown in the attached drawings. In some instances, all or many of the pieces of the reactor formed of quartz, such as welded quartz tubing, while other reactors are made from metal with appropriate corrosion resistant coatings such as quartz or other materials, e.g., corrosion resistant material, or stainless steel tubing or pipes may be used with a corrosion resistant material useful with HVPE-type reactants and gases. Using HVPE in the reactor allows use of lower-cost precursors at higher deposition rates such as in the range of 1 to 5 .mu.m/minute.

  7. Fundamentals of semiconductor processing technology

    CERN Document Server

    El-Kareh, Badih

    1995-01-01

    The drive toward new semiconductor technologies is intricately related to market demands for cheaper, smaller, faster, and more reliable circuits with lower power consumption. The development of new processing tools and technologies is aimed at optimizing one or more of these requirements. This goal can, however, only be achieved by a concerted effort between scientists, engineers, technicians, and operators in research, development, and manufac­ turing. It is therefore important that experts in specific disciplines, such as device and circuit design, understand the principle, capabil­ ities, and limitations of tools and processing technologies. It is also important that those working on specific unit processes, such as lithography or hot processes, be familiar with other unit processes used to manufacture the product. Several excellent books have been published on the subject of process technologies. These texts, however, cover subjects in too much detail, or do not cover topics important to modem tech­ n...

  8. Theory of Defects in Semiconductors

    CERN Document Server

    Drabold, David A

    2007-01-01

    Semiconductor science and technology is the art of defect engineering. The theoretical modeling of defects has improved dramatically over the past decade. These tools are now applied to a wide range of materials issues: quantum dots, buckyballs, spintronics, interfaces, amorphous systems, and many others. This volume presents a coherent and detailed description of the field, and brings together leaders in theoretical research. Today's state-of-the-art, as well as tomorrow’s tools, are discussed: the supercell-pseudopotential method, the GW formalism,Quantum Monte Carlo, learn-on-the-fly molecular dynamics, finite-temperature treatments, etc. A wealth of applications are included, from point defects to wafer bonding or the propagation of dislocation.

  9. High Volume Manufacturing of Silicon-Film Solar Cells and Modules; Final Subcontract Report, 26 February 2003 - 30 September 2003

    Energy Technology Data Exchange (ETDEWEB)

    Rand, J. A.; Culik, J. S.

    2005-10-01

    The objective of the PV Manufacturing R&D subcontract was to continue to improve AstroPower's technology for manufacturing Silicon-Film* wafers, solar cells, and modules to reduce costs, and increase production yield, throughput, and capacity. As part of the effort, new technology such as the continuous back metallization screen-printing system and the laser scribing system were developed and implemented. Existing processes, such as the silicon nitride antireflection coating system and the fire-through process were optimized. Improvements were made to the statistical process control (SPC) systems of the major manufacturing processes: feedstock preparation, wafer growth, surface etch, diffusion, and the antireflection coating process. These process improvements and improved process control have led to an increase of 5% relative power, and nearly 15% relative improvement in mechanical and visual yield.

  10. Diluted magnetic semiconductor nanowires exhibiting magnetoresistance

    Science.gov (United States)

    Yang, Peidong [El Cerrito, CA; Choi, Heonjin [Seoul, KR; Lee, Sangkwon [Daejeon, KR; He, Rongrui [Albany, CA; Zhang, Yanfeng [El Cerrito, CA; Kuykendal, Tevye [Berkeley, CA; Pauzauskie, Peter [Berkeley, CA

    2011-08-23

    A method for is disclosed for fabricating diluted magnetic semiconductor (DMS) nanowires by providing a catalyst-coated substrate and subjecting at least a portion of the substrate to a semiconductor, and dopant via chloride-based vapor transport to synthesize the nanowires. Using this novel chloride-based chemical vapor transport process, single crystalline diluted magnetic semiconductor nanowires Ga.sub.1-xMn.sub.xN (x=0.07) were synthesized. The nanowires, which have diameters of .about.10 nm to 100 nm and lengths of up to tens of micrometers, show ferromagnetism with Curie temperature above room temperature, and magnetoresistance up to 250 Kelvin.

  11. Semiconductor Nanostructures Quantum States and Electronic Transport

    CERN Document Server

    Ihn, Thomas

    2009-01-01

    This textbook describes the physics of semiconductor nanostructures with emphasis on their electronic transport properties. At its heart are five fundamental transport phenomena: quantized conductance, tunnelling transport, the Aharonov-Bohm effect, the quantum Hall effect, and the Coulomb blockade effect. The book starts out with the basics of solid state and semiconductor physics, such as crystal structure, band structure, and effective mass approximation, including spin-orbit interaction effects important for research in semiconductor spintronics. It contains material aspects such as band e

  12. Controlling the stoichiometry and doping of semiconductor materials

    Science.gov (United States)

    Albin, David; Burst, James; Metzger, Wyatt; Duenow, Joel; Farrell, Stuart; Colegrove, Eric

    2016-08-16

    Methods for treating a semiconductor material are provided. According to an aspect of the invention, the method includes annealing the semiconductor material in the presence of a compound that includes a first element and a second element. The first element provides an overpressure to achieve a desired stoichiometry of the semiconductor material, and the second element provides a dopant to the semiconductor material.

  13. Life-cycle assessment of semiconductors

    CERN Document Server

    Boyd, Sarah B

    2012-01-01

    Life-Cycle Assessment of Semiconductors presents the first and thus far only available transparent and complete life cycle assessment of semiconductor devices. A lack of reliable semiconductor LCA data has been a major challenge to evaluation of the potential environmental benefits of information technologies (IT). The analysis and results presented in this book will allow a higher degree of confidence and certainty in decisions concerning the use of IT in efforts to reduce climate change and other environmental effects. Coverage includes but is not limited to semiconductor manufacturing trends by product type and geography, unique coverage of life-cycle assessment, with a focus on uncertainty and sensitivity analysis of energy and global warming missions for CMOS logic devices, life cycle assessment of flash memory and life cycle assessment of DRAM. The information and conclusions discussed here will be highly relevant and useful to individuals and institutions. The book also: Provides a detailed, complete a...

  14. X-ray absorption spectroscopy of semiconductors

    CERN Document Server

    Ridgway, Mark

    2015-01-01

    X-ray Absorption Spectroscopy (XAS) is a powerful technique with which to probe the properties of matter, equally applicable to the solid, liquid and gas phases. Semiconductors are arguably our most technologically-relevant group of materials given they form the basis of the electronic and photonic devices that now so widely permeate almost every aspect of our society. The most effective utilisation of these materials today and tomorrow necessitates a detailed knowledge of their structural and vibrational properties. Through a series of comprehensive reviews, this book demonstrates the versatility of XAS for semiconductor materials analysis and presents important research activities in this ever growing field. A short introduction of the technique, aimed primarily at XAS newcomers, is followed by twenty independent chapters dedicated to distinct groups of materials. Topics span dopants in crystalline semiconductors and disorder in amorphous semiconductors to alloys and nanometric material as well as in-sit...

  15. Analysis and simulation of semiconductor devices

    CERN Document Server

    Selberherr, Siegfried

    1984-01-01

    The invention of semiconductor devices is a fairly recent one, considering classical time scales in human life. The bipolar transistor was announced in 1947, and the MOS transistor, in a practically usable manner, was demonstrated in 1960. From these beginnings the semiconductor device field has grown rapidly. The first integrated circuits, which contained just a few devices, became commercially available in the early 1960s. Immediately thereafter an evolution has taken place so that today, less than 25 years later, the manufacture of integrated circuits with over 400.000 devices per single chip is possible. Coincident with the growth in semiconductor device development, the literature concerning semiconductor device and technology issues has literally exploded. In the last decade about 50.000 papers have been published on these subjects. The advent of so called Very-Large-Scale-Integration (VLSI) has certainly revealed the need for a better understanding of basic device behavior. The miniaturization of the s...

  16. High throughput combinatorial screening of semiconductor materials

    Science.gov (United States)

    Mao, Samuel S.

    2011-11-01

    This article provides an overview of an advanced combinatorial material discovery platform developed recently for screening semiconductor materials with properties that may have applications ranging from radiation detectors to solar cells. Semiconductor thin-film libraries, each consisting of 256 materials of different composition arranged into a 16×16 matrix, were fabricated using laser-assisted evaporation process along with a combinatorial mechanism to achieve variations. The composition and microstructure of individual materials on each thin-film library were characterized with an integrated scanning micro-beam x-ray fluorescence and diffraction system, while the band gaps were determined by scanning optical reflection and transmission of the libraries. An ultrafast ultraviolet photon-induced charge probe was devised to measure the mobility and lifetime of individual thin-film materials on semiconductor libraries. Selected results on the discovery of semiconductors with desired band gaps and transport properties are illustrated.

  17. Semiconductor spintronics - Spins go their own way

    NARCIS (Netherlands)

    van Wees, Bart

    A semiconductor device that integrates electron spin injection, transport, modulation and detection in a single structure provides an important step in versatility for both fundamental research and practical spintronic applications.

  18. Plasmonic effects in metal-semiconductor nanostructures

    CERN Document Server

    Toropov, Alexey A

    2015-01-01

    Metal-semiconductor nanostructures represent an important new class of materials employed in designing advanced optoelectronic and nanophotonic devices, such as plasmonic nanolasers, plasmon-enhanced light-emitting diodes and solar cells, plasmonic emitters of single photons, and quantum devices operating in infrared and terahertz domains. The combination of surface plasmon resonances in conducting structures, providing strong concentration of an electromagnetic optical field nearby, with sharp optical resonances in semiconductors, which are highly sensitive to external electromagnetic fields, creates a platform to control light on the nanoscale. The design of the composite metal-semiconductor system imposes the consideration of both the plasmonic resonances in metal and the optical transitions in semiconductors - a key issue being their resonant interaction providing a coupling regime. In this book the reader will find descriptions of electrodynamics of conducting structures, quantum physics of semiconducto...

  19. Artificial Photosynthesis with Semiconductor-Liquid Junctions

    National Research Council Canada - National Science Library

    Guijarro, Néstor; Formal, Florian Le; Sivula, Kevin

    2015-01-01

    .... solar fuel engineering. In this review we give an overview of the field of artificial photosynthesis using a semiconductor-electrolyte interface employed in a photoelectrochemical device or as a heterogeneous photocatalyst...

  20. Photocatalytic semiconductors synthesis, characterization, and environmental applications

    CERN Document Server

    Hernández-Ramírez, Aracely

    2014-01-01

    This critical volume examines the different methods used for the synthesis of a great number of photocatalysts, including TiO2, ZnO and other modified semiconductors, as well as characterization techniques used for determining the optical, structural and morphological properties of the semiconducting materials. Additionally, the authors discuss photoelectrochemical methods for determining the light activity of the photocatalytic semiconductors by means of measurement of properties such as band gap energy, flat band potential and kinetics of hole and electron transfer. Photocatalytic Semiconductors: Synthesis, Characterization and Environmental Applications provide an overview of the semiconductor materials from first- to third-generation photocatalysts and their applications in wastewater treatment and water disinfection. The book further presents economic and toxicological aspects in the production and application of photocatalytic materials.

  1. Photo-induced strain imaging of semiconductors

    Directory of Open Access Journals (Sweden)

    Keiji Takata

    2017-04-01

    Full Text Available This paper presents a novel method for high-resolutions imaging of band-gap energies of semiconductors. When electron-hole pairs are generated in a semiconductor irradiated with a laser, they induce electronic strains in the semiconductor. The electronic strains can be detected and imaged by a scanning probe microscope. The electron-hole-pair generation depends on the band-gap and photon energies. When there are variations in band-gap energies in a sample, strains could be detected in regions having narrower gaps than the irradiated photon energy, and so their distributions can be imaged. The threshold of electron-hole-pair generation can be varied by changing the irradiated photon energies. Consequently, we can quantitatively image the band-gap energy distributions of semiconductors.

  2. Heteroepitaxy of semiconductors theory, growth, and characterization

    CERN Document Server

    Ayers, John E

    2007-01-01

    Heteroepitaxy has evolved rapidly in recent years. With each new wave of material/substrate combinations, our understanding of how to control crystal growth becomes more refined. Most books on the subject focus on a specific material or material family, narrowly explaining the processes and techniques appropriate for each. Surveying the principles common to all types of semiconductor materials, Heteroepitaxy of Semiconductors: Theory, Growth, and Characterization is the first comprehensive, fundamental introduction to the field. This book reflects our current understanding of nucleation, growth modes, relaxation of strained layers, and dislocation dynamics without emphasizing any particular material. Following an overview of the properties of semiconductors, the author introduces the important heteroepitaxial growth methods and provides a survey of semiconductor crystal surfaces, their structures, and nucleation. With this foundation, the book provides in-depth descriptions of mismatched heteroepitaxy and la...

  3. Nitride semiconductor devices fundamentals and applications

    CERN Document Server

    Morkoç, Hadis

    2013-01-01

    This book gives a clear presentation of the necessary basics of semiconductor and device physics and engineering. It introduces readers to fundamental issues that will enable them to follow the latest technological research. It also covers important applications, including LED and lighting, semiconductor lasers, high power switching devices, and detectors. This balanced and up-to-date treatment makes the text an essential educational tool for both advanced students and professionals in the electronics industry.

  4. Small-signal analysis of granular semiconductors

    Science.gov (United States)

    Varpula, Aapo; Sinkkonen, Juha; Novikov, Sergey

    2010-11-01

    The small-signal ac response of granular n-type semiconductors is calculated analytically using the drift-diffusion theory when electronic trapping at grain boundaries is present. An electrical equivalent circuit (EEC) model of a granular n-type semiconductor is presented. The analytical model is verified with numerical simulation performed by SILVACO ATLAS. The agreement between the analytical and numerical results is very good in a broad frequency range at low dc bias voltages.

  5. Work on the ATLAS semiconductor tracker barrel

    CERN Multimedia

    Maximilien Brice

    2005-01-01

    Precision work is performed on the semiconductor tracker barrel of the ATLAS experiment. All work on these delicate components must be performed in a clean room so that impurities in the air, such as dust, do not contaminate the detector. The semiconductor tracker will be mounted in the barrel close to the heart of the ATLAS experiment to detect the path of particles produced in proton-proton collisions.

  6. Basics of Semiconductor and Spin Physics

    Science.gov (United States)

    Dyakonov, M. I.

    This introductory chapter is mainly addressed to readers new to the field. In Sect. 1.1 a brief review of the historical roots of the current research is given. Section 1.2 describes various spin interactions. Section 1.3 is a mini textbook on semiconductor physics designed for beginners. A short overview of spin phenomena in semiconductors is given in Sect. 1.4. Finally, Sect. 1.5 presents the topics discussed in the chapters to follow.

  7. A Semiconductor Microlaser for Intracavity Flow Cytometry

    Energy Technology Data Exchange (ETDEWEB)

    Akhil, O.; Copeland, G.C.; Dunne, J.L.; Gourley, P.L.; Hendricks, J.K.; McDonald, A.E.

    1999-01-20

    Semiconductor microlasers are attractive components for micro-analysis systems because of their ability to emit coherent intense light from a small aperture. By using a surface-emitting semiconductor geometry, we were able to incorporate fluid flow inside a laser microcavity for the first time. This confers significant advantages for high throughput screening of cells, particulates and fluid analytes in a sensitive microdevice. In this paper we discuss the intracavity microfluidics and present preliminary results with flowing blood and brain cells.

  8. Semiconductor/High-Tc-Superconductor Hybrid ICs

    Science.gov (United States)

    Burns, Michael J.

    1995-01-01

    Hybrid integrated circuits (ICs) containing both Si-based semiconducting and YBa(2)Cu(3)O(7-x) superconducting circuit elements on sapphire substrates developed. Help to prevent diffusion of Cu from superconductors into semiconductors. These hybrid ICs combine superconducting and semiconducting features unavailable in superconducting or semiconducting circuitry alone. For example, complementary metal oxide/semiconductor (CMOS) readout and memory devices integrated with fast-switching Josephson-junction super-conducting logic devices and zero-resistance interconnections.

  9. Diffusion in semiconductors, other than silicon compilation

    CERN Document Server

    Fisher, David J

    2011-01-01

    Review from Book News Inc.: Summary reports of 337 experiments provide information on the diffusion of matter and heat in 31 materials used in semiconductors. Most of the compounds are based on cadmium, gallium, indium, lead, and zinc. Mercury telluride is included however, as is silicon carbide for some reason. Each article is thoroughly referenced to the authors and publication number, date, and page. The arrangement is alphabetical by semiconductor material. Indexes cover authors, hosts, and diffusants.

  10. Semiconductor saturable absorbers for ultrafast terahertz signals

    OpenAIRE

    Hoffmann, Matthias C.; Turchinovich, Dmitry

    2010-01-01

    We demonstrate saturable absorber behavior of n-type semiconductors GaAs, GaP, and Ge in the terahertz THz frequency range at room temperature using nonlinear THz spectroscopy. The saturation mechanism is based on a decrease in electron conductivity of semiconductors at high electron momentum states, due to conduction band onparabolicity and scattering into satellite valleys in strong THz fields. Saturable absorber parameters, such as linear and nonsaturable transmission, and saturation fluen...

  11. Semiconductor saturable absorbers for ultrafast THz signals

    DEFF Research Database (Denmark)

    Hoffmann, Matthias C.; Turchinovich, Dmitry

    We demonstrate saturable absorber behavior of n-type semiconductors in the THz frequency range using nonlinear THz spectroscopy. Further, we observe THz pulse shortening and increase of the group refractive index at high field strengths.......We demonstrate saturable absorber behavior of n-type semiconductors in the THz frequency range using nonlinear THz spectroscopy. Further, we observe THz pulse shortening and increase of the group refractive index at high field strengths....

  12. Semiconductor saturable absorbers for ultrafast terahertz signals

    OpenAIRE

    Hoffmann, Matthias C.; Turchinovich, Dmitry

    2010-01-01

    We demonstrate saturable absorber behavior of n-type semiconductorsGaAs,GaP, and Ge in the terahertz (THz) frequency range at room temperature using nonlinear THz spectroscopy. The saturation mechanism is based on a decrease in electron conductivity of semiconductors at high electron momentum states, due to conduction band nonparabolicity and scattering into satellite valleys in strong THz fields. Saturable absorber parameters, such as linear and nonsaturable transmission, and saturation flue...

  13. Investigation of semiconductor clad optical waveguides

    Science.gov (United States)

    Batchman, T. E.; Carson, R. F.

    1985-01-01

    A variety of techniques have been proposed for fabricating integrated optical devices using semiconductors, lithium niobate, and glasses as waveguides and substrates. The use of glass waveguides and their interaction with thin semiconductor cladding layers was studied. Though the interactions of these multilayer waveguide structures have been analyzed here using glass, they may be applicable to other types of materials as well. The primary reason for using glass is that it provides a simple, inexpensive way to construct waveguides and devices.

  14. Electron gas grid semiconductor radiation detectors

    Science.gov (United States)

    Lee, Edwin Y.; James, Ralph B.

    2002-01-01

    An electron gas grid semiconductor radiation detector (EGGSRAD) useful for gamma-ray and x-ray spectrometers and imaging systems is described. The radiation detector employs doping of the semiconductor and variation of the semiconductor detector material to form a two-dimensional electron gas, and to allow transistor action within the detector. This radiation detector provides superior energy resolution and radiation detection sensitivity over the conventional semiconductor radiation detector and the "electron-only" semiconductor radiation detectors which utilize a grid electrode near the anode. In a first embodiment, the EGGSRAD incorporates delta-doped layers adjacent the anode which produce an internal free electron grid well to which an external grid electrode can be attached. In a second embodiment, a quantum well is formed between two of the delta-doped layers, and the quantum well forms the internal free electron gas grid to which an external grid electrode can be attached. Two other embodiments which are similar to the first and second embodiment involve a graded bandgap formed by changing the composition of the semiconductor material near the first and last of the delta-doped layers to increase or decrease the conduction band energy adjacent to the delta-doped layers.

  15. Thermodynamical limits of diluted magnetic semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Buerger, Danilo; Seeger, Michael; Zhou, Shengqiang; Helm, Manfred; Schmidt, Heidemarie [Forschungszentrum Dresden-Rossendorf e.V., Bautzner Landstrasse 400, 01328 Dresden (Germany)

    2010-07-01

    The incorporation of transition metals dopants in semiconductors over their solubility limit is the main challenge for the fabrication of diluted ferromagnetic semiconductors. Dietl et al. calculated the Curie temperatures for various semiconductors doped with 5 at% Mn. A lot of experimental effort was focused on the fabrication of diluted magnetic semiconductors. Unfortunately, such metastable alloys try to reach their thermodynamical equilibrium by the diffusion of the incorporated dopants. The equilibrium state at room temperature for semiconductors with a low solubility of magnetic dopant atoms is characterized by unwanted secondary phases. We present the results from combined random walk simulations and heat-flow calculations and explain the successful fabrication of GaAs:Mn and the impossibility to produce diluted Si:Mn. The clustering process is simulated under the assumption that neighbouring magnetic atoms stick together. This is a general approach for the growth of clusters in supersaturated materials. With the knowledge of the diffusion coefficient our modelling can be used to predict the thermodynamical limit at room temperature and the producibility by pulsed laser annealing of diluted magnetic semiconductors.

  16. Templated Chemically Deposited Semiconductor Optical Fiber Materials

    Science.gov (United States)

    Sparks, Justin R.; Sazio, Pier J. A.; Gopalan, Venkatraman; Badding, John V.

    2013-07-01

    Chemical deposition is a powerful technology for fabrication of planar microelectronics. Optical fibers are the dominant platform for telecommunications, and devices such as fiber lasers are forming the basis for new industries. High-pressure chemical vapor deposition (HPCVD) allows for conformal layers and void-free wires of precisely doped crystalline unary and compound semiconductors inside the micro-to-nanoscale-diameter pores of microstructured optical fibers (MOFs). Drawing the fibers to serve as templates into which these semiconductor structures can be fabricated allows for geometric design flexibility that is difficult to achieve with planar fabrication. Seamless coupling of semiconductor optoelectronic and photonic devices with existing fiber infrastructure thus becomes possible, facilitating all-fiber technological approaches. The deposition techniques also allow for a wider range of semiconductor materials compositions to be exploited than is possible by means of preform drawing. Gigahertz bandwidth junction-based fiber devices can be fabricated from doped crystalline semiconductors, for example. Deposition of amorphous hydrogenated silicon, which cannot be drawn, allows for the exploitation of strong nonlinear optical function in fibers. Finally, crystalline compound semiconductor fiber cores hold promise for high-power infrared light-guiding fiber devices and subwavelength-resolution, large-area infrared imaging.

  17. Electrolysis of a molten semiconductor

    Science.gov (United States)

    Yin, Huayi; Chung, Brice; Sadoway, Donald R.

    2016-01-01

    Metals cannot be extracted by electrolysis of transition-metal sulfides because as liquids they are semiconductors, which exhibit high levels of electronic conduction and metal dissolution. Herein by introduction of a distinct secondary electrolyte, we reveal a high-throughput electro-desulfurization process that directly converts semiconducting molten stibnite (Sb2S3) into pure (99.9%) liquid antimony and sulfur vapour. At the bottom of the cell liquid antimony pools beneath cathodically polarized molten stibnite. At the top of the cell sulfur issues from a carbon anode immersed in an immiscible secondary molten salt electrolyte disposed above molten stibnite, thereby blocking electronic shorting across the cell. As opposed to conventional extraction practices, direct sulfide electrolysis completely avoids generation of problematic fugitive emissions (CO2, CO and SO2), significantly reduces energy consumption, increases productivity in a single-step process (lower capital and operating costs) and is broadly applicable to a host of electronically conductive transition-metal chalcogenides. PMID:27553525

  18. Quantum transport in semiconductor nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Kubis, Tillmann Christoph

    2009-11-15

    The main objective of this thesis is to theoretically predict the stationary charge and spin transport in mesoscopic semiconductor quantum devices in the presence of phonons and device imperfections. It is well known that the nonequilibrium Green's function method (NEGF) is a very general and all-inclusive scheme for the description of exactly this kind of transport problem. Although the NEGF formalism has been derived in the 1960's, textbooks about this formalism are still rare to find. Therefore, we introduce the NEGF formalism, its fundamental equations and approximations in the first part of this thesis. Thereby, we extract ideas of several seminal contributions on NEGF in literature and augment this by some minor derivations that are hard to find. Although the NEGF method has often been numerically implemented on transport problems, all current work in literature is based on a significant number of approximations with often unknown influence on the results and unknown validity limits. Therefore, we avoid most of the common approximations and implement in the second part of this thesis the NEGF formalism as exact as numerically feasible. For this purpose, we derive several new scattering self-energies and introduce new self-adaptive discretizations for the Green's functions and self-energies. The most important improvements of our NEGF implementation, however, affect the momentum and energy conservation during incoherent scattering, the Pauli blocking, the current conservation within and beyond the device and the reflectionless propagation through open device boundaries. Our uncommonly accurate implementation of the NEGF method allows us to analyze and assess most of the common approximations and to unveil numerical artifacts that have plagued previous approximate implementations in literature. Furthermore, we apply our numerical implementation of the NEGF method on the stationary electron transport in THz quantum cascade lasers (QCLs) and answer

  19. Majorana fermions in semiconductor nanowires

    Science.gov (United States)

    Stanescu, Tudor D.; Lutchyn, Roman M.; Das Sarma, S.

    2011-10-01

    We study multiband semiconducting nanowires proximity coupled with an s-wave superconductor and calculate the topological phase diagram as a function of the chemical potential and magnetic field. The nontrivial topological state corresponds to a superconducting phase supporting an odd number of pairs of Majorana modes localized at the ends of the wire, whereas the nontopological state corresponds to a superconducting phase with no Majoranas or with an even number of pairs of Majorana modes. Our key finding is that multiband occupancy not only lifts the stringent constraint of one-dimensionality, but also allows having higher carrier density in the nanowire. Consequently, multiband nanowires are better suited for stabilizing the topological superconducting phase and for observing the Majorana physics. We present a detailed study of the parameter space for multiband semiconductor nanowires focusing on understanding the key experimental conditions required for the realization and detection of Majorana fermions in solid-state systems. We include various sources of disorder and characterize their effects on the stability of the topological phase. Finally, we calculate the local density of states as well as the differential tunneling conductance as functions of external parameters and predict the experimental signatures that would establish the existence of emergent Majorana zero-energy modes in solid-state systems.

  20. Annual Check-up

    Science.gov (United States)

    ... Medical Conditions Nutrition & Fitness Emotional Health Annual Check-Up Posted under Health Guides . Updated 24 April 2017. + ... I get ready for my annual medical check-up? If this is your first visit to your ...

  1. Evaluation of the Potential for the Production of Lignocellulosic Based Ethanol at Existing Corn Ethanol Facilities: Final Subcontract Report, 2 March 2000 - 30 March 2002

    Energy Technology Data Exchange (ETDEWEB)

    2002-07-01

    Subcontract report on opportunities to explore the business potential provided by converting biomass to products such as ethanol. The goals of this study were: (1) To provide the opportunity to explore the business potential provided by converting biomass to products such as ethanol. (2) To take advantage of the grain-processing infrastructure by investigating the co-location of additional biomass conversion facilities at an existing plant site.

  2. Electron-phonon interaction in a semiconductor quantum wire embedded into the semiconductor medium

    CERN Document Server

    Zharkoj, V P

    2002-01-01

    The renormalization of electron ground state energy due to the different types of interaction with confined (L) and interface (I) phonons in a semiconductor cylindrical quantum wire (QW) embedded into the semiconductor medium by the example of a HgS/CdS nanosystem.

  3. Lateral Mode Control of Semiconductor Lasers

    Science.gov (United States)

    Sun, Yan

    This thesis deals with several topics related to the lateral modes of edge-emitting semiconductor lasers. The first topic is the improvement of lateral beam quality for high power operation. A thermally controlled antiguiding unstable-resonator semiconductor laser with cleaved facets is proposed. With temperature controlled by monolithically integrated micro-heaters, the beam propagation factor is improved by 8 times at 300 mW and by 6 time at 600 mW. The second issue is monolithic semiconductor laser beam steering. Two new mechanisms, thermally controlled offset gain and index guiding lasers and fan laser arrays, have been proposed and demonstrated. They both have single-lobed Gaussian intensity distributions. The fan laser array has shown a total steering angle of 80^circ with eleven resolvable spots, which surpasses the previous results by a factor of three. The third issue is the nonlinear interaction between the semiconductor gain medium and optical waves. The filamentation effect is studied with perturbation theory. Analytical spatial solitary waves have been obtained. The fourth issue is the complex Hermite-Gaussian functions and their applications. An analytical integral expression has been obtained. The generalized complex Gaussian duct is discussed. It is found that the biorthogonal mode expansion and adjoint mode coupling theory in unstable resonators need to be improved. The fifth issue is the lateral modes of stable resonator and stadium resonator semiconductor lasers which have been designed, fabricated and tested. For the stable cavity semiconductor lasers, three distinct operation regions are identified as the stable cavity region, the transition region, and the geometrically unstable region. Preliminary results on stadium resonator semiconductor lasers have also been obtained.

  4. Localized Surface Plasmon Resonance in Semiconductor Nanocrystals.

    Science.gov (United States)

    Agrawal, Ankit; Cho, Shin Hum; Zandi, Omid; Ghosh, Sandeep; Johns, Robert W; Milliron, Delia J

    2018-02-05

    Localized surface plasmon resonance (LSPR) in semiconductor nanocrystals (NCs) that results in resonant absorption, scattering, and near field enhancement around the NC can be tuned across a wide optical spectral range from visible to far-infrared by synthetically varying doping level, and post synthetically via chemical oxidation and reduction, photochemical control, and electrochemical control. In this review, we will discuss the fundamental electromagnetic dynamics governing light matter interaction in plasmonic semiconductor NCs and the realization of various distinctive physical properties made possible by the advancement of colloidal synthesis routes to such NCs. Here, we will illustrate how free carrier dielectric properties are induced in various semiconductor materials including metal oxides, metal chalcogenides, metal nitrides, silicon, and other materials. We will highlight the applicability and limitations of the Drude model as applied to semiconductors considering the complex band structures and crystal structures that predominate and quantum effects that emerge at nonclassical sizes. We will also emphasize the impact of dopant hybridization with bands of the host lattice as well as the interplay of shape and crystal structure in determining the LSPR characteristics of semiconductor NCs. To illustrate the discussion regarding both physical and synthetic aspects of LSPR-active NCs, we will focus on metal oxides with substantial consideration also of copper chalcogenide NCs, with select examples drawn from the literature on other doped semiconductor materials. Furthermore, we will discuss the promise that LSPR in doped semiconductor NCs holds for a wide range of applications such as infrared spectroscopy, energy-saving technologies like smart windows and waste heat management, biomedical applications including therapy and imaging, and optical applications like two photon upconversion, enhanced luminesence, and infrared metasurfaces.

  5. EFG Technology and Diagnostic R&D for Large-Scale PV Manufacturing; Final Subcontract Report, 1 March 2002 - 31 March 2005

    Energy Technology Data Exchange (ETDEWEB)

    Kalejs, J.; Aurora, P.; Bathey, B.; Cao, J.; Doedderlein, J.; Gonsiorawski, R.; Heath, B.; Kubasti, J.; Mackintosh, B.; Ouellette, M.; Rosenblum, M.; Southimath, S.; Xavier, G.

    2005-10-01

    The objective of this subcontract was to carry out R&D to advance the technology, processes, and performance of RWE Schott-Solar's wafer, cell, and module manufacturing lines, and help configure these lines for scaling up of edge-defined, film-fed growth (EFG) ribbon technology to the 50-100 MW PV factory level. EFG ribbon manufacturing continued to expand during this subcontract period and now has reached a capacity of 40 MW. EFG wafer products were diversified over this time period. In addition to 10 cm x 10 cm and 10 cm x 15 cm wafer areas, which were the standard products at the beginning of this program, R&D has focused on new EFG technology to extend production to 12.5 cm x 12.5 cm EFG wafers. Cell and module production also has continued to expand in Billerica. A new 12-MW cell line was installed and brought on line in 2003. R&D on this subcontract improved cell yield and throughput, and optimized the cell performance, with special emphasis on work to speed up wafer transfer, hence enhancing throughput. Improvements of wafer transfer processes during this program have raised cell line capacity from 12 MW to over 18 MW. Optimization of module manufacturing processes was carried out on new equipment installed during a manufacturing upgrade in Billerica to a 12-MW capacity to improve yield and reliability of products.

  6. Organic semiconductor distributed feedback lasers

    Science.gov (United States)

    Kowalsky, W.; Rabe, T.; Schneider, D.; Johannes, H.-H.; Karnutsch, C.; Gerken, M.; Lemmer, U.; Wang, J.; Weimann, T.; Hinze, P.; Riedl, T.

    2005-11-01

    Compared to well established liquid based dye lasers, amplifying media based on amorphous organic thin films allow the realisation of versatile, cost effective and compact lasers. Aside from that, the materials involved are organic semiconductors, which in principle allow the fabrication of future electrically driven organic laser diodes. A highly promising, low-loss resonator geometry for these lasers is the distributed feedback (DFB) structure, which is based on a periodic modulation of the refractive index in the waveguide on the nanometer scale. By variation of the grating period Λ one may tune the laser emission within the gain spectrum of the amplifying medium. We will demonstrate organic lasers spanning the entire spectral region from 360-715 nm. Tuning ranges as large as 115 nm (λ = 598-713 nm) in the red spectral region and more than 30 nm (λ = 362-394 nm) in the UV render these novel lasers highly attractive for various spectroscopic applications. As the grating period Λ is typically between 100 nm and 400 nm the DFB resonators are fabricated by e-beam lithography. These gratings may, however, be used as masters to obtain an arbitrary amount of copies by nanoimprint lithography into plastic substrates. Therefore these lasers are very attractive even for single-use applications (e.g. in medicine and biotechnology). Today, the key challenge in the field is the realisation of the first electrically driven organic laser. Key pre-requisites are highly efficient amplifying material systems which allow for low threshold operation and charge transport materials that bring about the stability to sustain the necessary current densities, several orders of magnitude higher than in OLEDs. We will demonstrate diode structures operated electrically under pulsed conditions at current densities up to 760 A/cm2 with a product of the current density and the external quantum effciency (J×η ext) of 1.27 A/cm2. Mechanisms deteriorating the quantum efficieny at elevated

  7. Paul Scherrer Institut annual report 1996. Annex IIIB: applied solid state physics

    Energy Technology Data Exchange (ETDEWEB)

    Kuse, D. [ed.] [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-09-01

    The annual report presents F3B highlights and reports on progress achieved during 1966 in the field of nanotechnology, semiconductor quantum structure, optoelectronic devices, micro- and integrated optics, optical metrology, new installations. A list of publications is also presented. figs., tabs., refs.

  8. ISCR FY2005 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    Keyes, D E; McGraw, J R

    2006-02-02

    Large-scale scientific computation and all of the disciplines that support and help validate it have been placed at the focus of Lawrence Livermore National Laboratory (LLNL) by the Advanced Simulation and Computing (ASC) program of the National Nuclear Security Administration (NNSA) and the Scientific Discovery through Advanced Computing (SciDAC) initiative of the Office of Science of the Department of Energy (DOE). The maturation of simulation as a fundamental tool of scientific and engineering research is underscored in the President's Information Technology Advisory Committee (PITAC) June 2005 finding that ''computational science has become critical to scientific leadership, economic competitiveness, and national security''. LLNL operates several of the world's most powerful computers--including today's single most powerful--and has undertaken some of the largest and most compute-intensive simulations ever performed, most notably the molecular dynamics simulation that sustained more than 100 Teraflop/s and won the 2005 Gordon Bell Prize. Ultrascale simulation has been identified as one of the highest priorities in DOE's facilities planning for the next two decades. However, computers at architectural extremes are notoriously difficult to use in an efficient manner. Furthermore, each successful terascale simulation only points out the need for much better ways of interacting with the resulting avalanche of data. Advances in scientific computing research have, therefore, never been more vital to the core missions of LLNL than at present. Computational science is evolving so rapidly along every one of its research fronts that to remain on the leading edge, LLNL must engage researchers at many academic centers of excellence. In FY 2005, the Institute for Scientific Computing Research (ISCR) served as one of LLNL's main bridges to the academic community with a program of collaborative subcontracts, visiting faculty

  9. Inorganic Chemistry Solutions to Semiconductor Nanocrystal Problems

    Energy Technology Data Exchange (ETDEWEB)

    Alvarado, Samuel R. [Ames Laboratory; Guo, Yijun [Ames Laboratory; Ruberu, T. Purnima A. [Ames Laboratory; Tavasoli, Elham [Ames Laboratory; Vela, Javier [Ames Laboratory

    2014-03-15

    The optoelectronic and chemical properties of semiconductor nanocrystals heavily depend on their composition, size, shape and internal structure, surface functionality, etc. Available strategies to alter these properties through traditional colloidal syntheses and ligand exchange methods place a premium on specific reaction conditions and surfactant combinations. In this invited review, we apply a molecular-level understanding of chemical precursor reactivity to reliably control the morphology, composition and intimate architecture (core/shell vs. alloyed) of semiconductor nanocrystals. We also describe our work aimed at achieving highly selective, low-temperature photochemical methods for the synthesis of semiconductor–metal and semiconductor–metal oxide photocatalytic nanocomposites. In addition, we describe our work on surface modification of semiconductor nanocrystal quantum dots using new approaches and methods that bypass ligand exchange, retaining the nanocrystal's native ligands and original optical properties, as well as on spectroscopic methods of characterization useful in determining surface ligand organization and chemistry. Using recent examples from our group and collaborators, we demonstrate how these efforts have lead to faster, wider and more systematic application of semiconductor nanocrystal-based materials to biological imaging and tracking, and to photocatalysis of unconventional substrates. We believe techniques and methods borrowed from inorganic chemistry (including coordination, organometallic and solid state chemistry) have much to offer in reaching a better understanding of the synthesis, functionalization and real-life application of such exciting materials as semiconductor nanocrystals (quantum dots, rods, tetrapods, etc.).

  10. Extracting hot carriers from photoexcited semiconductor nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Xiaoyang

    2014-12-10

    This research program addresses a fundamental question related to the use of nanomaterials in solar energy -- namely, whether semiconductor nanocrystals (NCs) can help surpass the efficiency limits, the so-called “Shockley-Queisser” limit, in conventional solar cells. In these cells, absorption of photons with energies above the semiconductor bandgap generates “hot” charge carriers that quickly “cool” to the band edges before they can be utilized to do work; this sets the solar cell efficiency at a limit of ~31%. If instead, all of the energy of the hot carriers could be captured, solar-to-electric power conversion efficiencies could be increased, theoretically, to as high as 66%. A potential route to capture this energy is to utilize semiconductor nanocrystals. In these materials, the quasi-continuous conduction and valence bands of the bulk semiconductor become discretized due to confinement of the charge carriers. Consequently, the energy spacing between the electronic levels can be much larger than the highest phonon frequency of the lattice, creating a “phonon bottleneck” wherein hot-carrier relaxation is possible via slower multiphonon emission. For example, hot-electron lifetimes as long as ~1 ns have been observed in NCs grown by molecular beam epitaxy. In colloidal NCs, long lifetimes have been demonstrated through careful design of the nanocrystal interfaces. Due to their ability to slow electronic relaxation, semiconductor NCs can in principle enable extraction of hot carriers before they cool to the band edges, leading to more efficient solar cells.

  11. NREL photovoltaic program FY 1997 annual report

    Energy Technology Data Exchange (ETDEWEB)

    McConnell, R.D.; Hansen, A.; Smoller, S.

    1998-06-01

    This report summarizes the in-house and subcontracted research and development (R and D) activities under the NREL PV Program from October 1, 1996, through September 30, 1997 (FY 1997). The NREL PV Program is part of the US Department of Energy`s (DOE`s) National Photovoltaics Program, as described in the DOE National Photovoltaics Program Plan for 1996--2000. The FY 1997 budget authority for carrying out the NREL PV Program was $39.3 million in operating funds and $0.4 million in capital equipment funds. Subcontract activities represent a major part of the NREL PV Program, with $21.8 million (55% of PV funds) going to some 84 subcontractors. Cost sharing by industry added almost $8.8 million to the subcontract R and D activities with industry.

  12. Polycrystalline thin-film cadmium telluride solar cells fabricated by electrodeposition. Annual subcontract report, 20 March 1992--19 March 1993

    Energy Technology Data Exchange (ETDEWEB)

    Trefny, J.U.; Furtak, T.E.; Wada, N.; Williamson, D.L.; Kim, D. [Colorado School of Mines, Golden, CO (US)

    1993-08-01

    This report describes progress during the first year of a 3-year program at Colorado School of Mines, based upon earlier studies performed by Ametek Corporation, to develop specific layers of the Ametek n-i-p structure as well as additional studies of several transparent conducting oxides. Thin films of ZnO and ZnO:Al were deposited under various conditions. For the n-layer of the Ametek structure, a dip-coating method was developed for the deposition of CdS films. The authors also present data on the characterization of these films by X-ray diffraction, Raman spectroscopy, scanning tunneling microscopy, small-angle X-ray scattering, and other techniques. They made progress in the electrodeposition of the CdTe i-layer of the Ametek structure. They developed appropriate electrochemical baths and are beginning to understand the role of the many experimental parameters that must be controlled to obtain high-quality films of this material. They explored the possibility of using an electrochemical process for fabricating the ZnTe p-layer. Some preliminary success was achieved, and this step will be pursued in the next phase. Finally, they fabricated a number of ``dot`` solar cells with the structure glass/SnO{sub 2}/CdS/CdTe/Au. Several cells with efficiencies in the range of 5%-6% were obtained, and they are confident, given recent progress, that cells with efficiencies in excess of 10% will be achieved in the near future.

  13. Photocharge transport and recombination measurements in amorphous silicon films and solar cells by photoconductive frequency mixing. Annual subcontract report, May 13, 1994--May 12, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Braunstein, R; Yang, Y; Dong, S [Univ. of California, Los Angeles, CA (United States)

    1995-10-01

    The continuous decay of electron drift mobility in intrinsic a-Si:H and a-SiC:H upon light soaking was investigated by the photomixing technique. The photoconductivity, lifetime and drift mobility in intrinsic hydrogenated amorphous silicon (a-Si:H) and hydrogenated amorphous silicon carbide (a-SiC:H) while light-soaking were determined using a photomixing technique. In addition to the decay of the photoconductivity and electron lifetime, continuous decay of the electron drift mobility was found during the light soaking process, which reveals a new phenomenon associated with the Staebler-Wronski effect. The drift mobility decreased by a factor of 2 for 20 hour light soaking at 2.5 sun intensity. Experimental data were fitted to a stretched exponential law. Different stretched-exponential parameters for photoconductivity, lifetime and drift mobility were obtained, which indicates the production of defects with different generation kinetics upon light soaking.

  14. Optimization of transparent and reflecting electrodes for amorphous silicon solar cells. Annual subcontract report, 1 May 1991--30 April 1992

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, R.G. [Harvard Univ., Cambridge, MA (United States). Dept. of Chemistry

    1993-04-01

    This report describes work to improve the performance of solar cells by improving the electrical and optical properties of their transparent conducting oxides (TCO) layers. Boron-doped zinc-oxide films were deposited by atmospheric pressure chemical vapor deposition in a laminar-flow reactor from diethyl zinc, tert-butanol, and diborane in the temperature range between 300{degrees}C and 420{degrees}C. When the deposition temperature was above 320{degrees}C, both doped and undoped films have highly oriented crystallites with their c-axes perpendicular to the substrate plane. Films deposited from 0.07% diethyl zinc and 2.4% tert-butanol have electron densities between 3.5 {times} 10{sup 20} cm{sup {minus}3} and 5.5 {times} 10{sup 20} cm{sup {minus}3}, conductivities between 250 {Omega}{sup {minus}1} and 2500 {Omega}{sup {minus}1} and mobilities between 2.5 cm{sup 2}/V-s and 35.0 cm{sup 2}/V-s, depending on dopant concentration, film thickness, and deposition temperature. Optical measurements show that the maximum infrared reflectance of the doped films is close to 90%, compared to about 20% for undoped films. Film visible absorption and film conductivity were found to increase with film thickness. The ratio of conductivity to visible absorption coefficient for doped films was between 0.1 {Omega} and 1.1 {Omega}{sup {minus}1}. The band gap of the film changes from 3.3 eV to 3.7 eV when the film is doped with 0.012% diborane.

  15. Microstructure of amorphous-silicon-based solar cell materials by small-angle x-ray scattering. Annual subcontract report, 6 April 1994--5 April 1995

    Energy Technology Data Exchange (ETDEWEB)

    Williamson, D.L. [Colorado School of Mines, Golden, CO (United States)

    1995-08-01

    The general objective of this research is to provide detailed microstructural information on the amorphous-silicon-based, thin-film materials under development for improved multijunction solar cells. The experimental technique used is small-angle x-ray scattering (SAXS) providing microstructural data on microvoid fractions, sizes, shapes, and their preferred orientations. Other microstructural features such as alloy segregation, hydrogen-rich clusters and alloy short-range order are probed.

  16. Advanced processing technology for high-efficiency thin-film CuInSe{sub 2} solar cells. Annual subcontract report, 1 March 1992--28 February 1993

    Energy Technology Data Exchange (ETDEWEB)

    Morel, D.L.; Attar, G.; Karthikeyan, S.; Muthaiah, A.; Zafar, A. [University of South Florida, Tampa, FL (United States)

    1993-08-01

    This report describes work to develop novel fabrication for CuInSe{sub 2} (CIS) solar cells that will result in improved performance and cost effectiveness at the manufacturing level. The primary approach involves all solid-state processing for CIS. This was augmented by work to provide novel alternatives for the formation of the window layer/heterojunction contact. Inherent to the project was the need to develop a generic understanding of the relationship between processing and performance so that broad-based transfer to industry can be facilitated. We achieved good-electronic-quality CIS by the use of two selenization procedures for predeposited metal layers. We achieved good stoichiometry throughout the bulk of the film, attained grain sizes of up to 1 {mu}m, and measured electron mobilities of up to 60 cm{sup 2}V-s. However, there is a complex relationship between grain size, adhesion, and performance. Our primary approach to characterization was to fabricate ZnO/CIS test devices and measure as many properties as possible in device format. We are also developing reactive sputtering of ZnO as an alternative window layer technology.

  17. Optical Biosensors Based on Semiconductor Nanostructures

    Directory of Open Access Journals (Sweden)

    Raúl J. Martín-Palma

    2009-06-01

    Full Text Available The increasing availability of semiconductor-based nanostructures with novel and unique properties has sparked widespread interest in their use in the field of biosensing. The precise control over the size, shape and composition of these nanostructures leads to the accurate control of their physico-chemical properties and overall behavior. Furthermore, modifications can be made to the nanostructures to better suit their integration with biological systems, leading to such interesting properties as enhanced aqueous solubility, biocompatibility or bio-recognition. In the present work, the most significant applications of semiconductor nanostructures in the field of optical biosensing will be reviewed. In particular, the use of quantum dots as fluorescent bioprobes, which is the most widely used application, will be discussed. In addition, the use of some other nanometric structures in the field of biosensing, including porous semiconductors and photonic crystals, will be presented.

  18. Developing New Nanoprobes from Semiconductor Nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Aihua [Univ. of California, Berkeley, CA (United States)

    2006-01-01

    In recent years, semiconductor nanocrystal quantum dots havegarnered the spotlight as an important new class of biological labelingtool. Withoptical properties superior to conventional organicfluorophores from many aspects, such as high photostability andmultiplexing capability, quantum dots have been applied in a variety ofadvanced imaging applications. This dissertation research goes along withlarge amount of research efforts in this field, while focusing on thedesign and development of new nanoprobes from semiconductor nanocrystalsthat are aimed for useful imaging or sensing applications not possiblewith quantum dots alone. Specifically speaking, two strategies have beenapplied. In one, we have taken advantage of the increasing capability ofmanipulating the shape of semiconductor nanocrystals by developingsemiconductor quantum rods as fluorescent biological labels. In theother, we have assembled quantum dots and gold nanocrystals into discretenanostructures using DNA. The background information and synthesis,surface manipulation, property characterization and applications of thesenew nanoprobes in a few biological experiments are detailed in thedissertation.

  19. Band structure engineering in organic semiconductors

    Science.gov (United States)

    Schwarze, Martin; Tress, Wolfgang; Beyer, Beatrice; Gao, Feng; Scholz, Reinhard; Poelking, Carl; Ortstein, Katrin; Günther, Alrun A.; Kasemann, Daniel; Andrienko, Denis; Leo, Karl

    2016-06-01

    A key breakthrough in modern electronics was the introduction of band structure engineering, the design of almost arbitrary electronic potential structures by alloying different semiconductors to continuously tune the band gap and band-edge energies. Implementation of this approach in organic semiconductors has been hindered by strong localization of the electronic states in these materials. We show that the influence of so far largely ignored long-range Coulomb interactions provides a workaround. Photoelectron spectroscopy confirms that the ionization energies of crystalline organic semiconductors can be continuously tuned over a wide range by blending them with their halogenated derivatives. Correspondingly, the photovoltaic gap and open-circuit voltage of organic solar cells can be continuously tuned by the blending ratio of these donors.

  20. Vertical external cavity surface emitting semiconductor lasers

    CERN Document Server

    Holm, M

    2001-01-01

    Active stabilisation showed a relative locked linewidth of approx 3 kHz. Coarse tuning over 7 nm was achieved using a 3-plate birefingent filter plate while fine-tuning using cavity length change allowed tuning over 250 MHz. Vertical external cavity semiconductor lasers have emerged as an interesting technology based on current vertical cavity semiconductor laser knowledge. High power output into a single transverse mode has attracted companies requiring good fibre coupling for telecommunications systems. The structure comprises of a grown semiconductor Bragg reflector topped with a multiple quantum well gain region. This is then included in an external cavity. This device is then optically pumped to promote laser action. Theoretical modelling of AIGaAs based VECSEL structures was undertaken, showing the effect of device design on laser characteristics. A simple 3-mirror cavity was constructed to assess the static characteristics of the structure. Up to 153 mW of output power was achieved in a single transver...

  1. Reliability and radiation effects in compound semiconductors

    CERN Document Server

    Johnston, Allan

    2010-01-01

    This book discusses reliability and radiation effects in compound semiconductors, which have evolved rapidly during the last 15 years. Johnston's perspective in the book focuses on high-reliability applications in space, but his discussion of reliability is applicable to high reliability terrestrial applications as well. The book is important because there are new reliability mechanisms present in compound semiconductors that have produced a great deal of confusion. They are complex, and appear to be major stumbling blocks in the application of these types of devices. Many of the reliability problems that were prominent research topics five to ten years ago have been solved, and the reliability of many of these devices has been improved to the level where they can be used for ten years or more with low failure rates. There is also considerable confusion about the way that space radiation affects compound semiconductors. Some optoelectronic devices are so sensitive to damage in space that they are very difficu...

  2. High pressure in semiconductor physics II

    CERN Document Server

    Willardson, R K; Suski, Tadeusz; Paul, William

    1998-01-01

    Since its inception in 1966, the series of numbered volumes known as Semiconductors and Semimetals has distinguished itself through the careful selection of well-known authors, editors, and contributors. The "Willardson and Beer" Series, as it is widely known, has succeeded in publishing numerous landmark volumes and chapters. Not only did many of these volumes make an impact at the time of their publication, but they continue to be well-cited years after their original release. Recently, Professor Eicke R. Weber of the University of California at Berkeley joined as a co-editor of the series. Professor Weber, a well-known expert in the field of semiconductor materials, will further contribute to continuing the series' tradition of publishing timely, highly relevant, and long-impacting volumes. Some of the recent volumes, such as Hydrogen in Semiconductors, Imperfections in III/V Materials, Epitaxial Microstructures, High-Speed Heterostructure Devices, Oxygen in Silicon, and others promise indeed that this tra...

  3. Optical Anisotropy of Topologically Distorted Semiconductor Nanocrystals.

    Science.gov (United States)

    Baimuratov, Anvar S; Pereziabova, Tatiana P; Zhu, Weiren; Leonov, Mikhail Yu; Baranov, Alexander V; Fedorov, Anatoly V; Rukhlenko, Ivan D

    2017-09-13

    Engineering nanostructured optical materials via the purposeful distortion of their constituent nanocrystals requires the knowledge of how various distortions affect the nanocrystals' electronic subsystem and its interaction with light. We use the geometric theory of defects in solids to calculate the linear permittivity tensor of semiconductor nanocrystals whose crystal lattice is arbitrarily distorted by imperfections or strains. The result is then employed to systematically analyze the optical properties of nanocrystals with spatial dispersion caused by screw dislocations and Eshelby twists. We demonstrate that Eshelby twists create gyrotropy in nanocrystals made of isotropic semiconductors whereas screw dislocations can produce it only if the nanocrystal material itself is inherently anisotropic. We also show that the dependence of circular dichroism spectrum on the aspect ratio of dislocation-distorted semiconductor nanorods allows resonant enhancing their optical activity (at least by a factor of 2) and creating highly optically active nanomaterials.

  4. Semiconductor laser using multimode interference principle

    Science.gov (United States)

    Gong, Zisu; Yin, Rui; Ji, Wei; Wu, Chonghao

    2018-01-01

    Multimode interference (MMI) structure is introduced in semiconductor laser used in optical communication system to realize higher power and better temperature tolerance. Using beam propagation method (BPM), Multimode interference laser diode (MMI-LD) is designed and fabricated in InGaAsP/InP based material. As a comparison, conventional semiconductor laser using straight single-mode waveguide is also fabricated in the same wafer. With a low injection current (about 230 mA), the output power of the implemented MMI-LD is up to 2.296 mW which is about four times higher than the output power of the conventional semiconductor laser. The implemented MMI-LD exhibits stable output operating at the wavelength of 1.52 μm and better temperature tolerance when the temperature varies from 283.15 K to 293.15 K.

  5. Fundamentals of semiconductors physics and materials properties

    CERN Document Server

    Yu, Peter Y

    1996-01-01

    Fundamentals of Semiconductors attempts to fill the gap between a general solid-state physics textbook and research articles by providing detailed explanations of the electronic, vibrational, transport, and optical properties of semiconductors The approach is physical and intuitive rather than formal and pedantic Theories are presented to explain experimental results This textbook has been written with both students and researchers in mind Its emphasis is on understanding the physical properties of Si and similar tetrahedrally coordinated semiconductors The explanations are based on physical insights Each chapter is enriched by an extensive collection of tables of material parameters, figures and problems Many of these problems 'lead the student by the hand' to arrive at the results

  6. Ion beams in semiconductor physics and technology

    Energy Technology Data Exchange (ETDEWEB)

    Kalbitzer, S. (Max-Planck-Inst. fuer Kernphysik, Heidelberg (Germany))

    1992-01-01

    The remarkable progress during the last two decades in semiconductor device technology is partly due to the introduction of ion beams as a key instrument for the modification and analysis of semiconductors. The basic reason is seen in the inherent electrical property of ion beams to be accurately controllable in energy, dose and species. The basic penetration and incorporation mechanisms in elemental and compound semiconductors have been explored and growing agreement between experiment and theory has rendered ion implantation a predictable tool. Similarly, the high analytic potential of nuclear reactions with ion beams has been steadily exploited and outstanding results have been achieved. Some basic milestones in the development of the ion beam techniques will be reviewed and future trends discussed. (orig.).

  7. Fundamentals of semiconductors physics and materials properties

    CERN Document Server

    Yu, Peter Y

    2010-01-01

    This fourth edition of the well-established Fundamentals of Semiconductors serves to fill the gap between a general solid-state physics textbook and research articles by providing detailed explanations of the electronic, vibrational, transport, and optical properties of semiconductors. The approach is physical and intuitive rather than formal and pedantic. Theories are presented to explain experimental results. This textbook has been written with both students and researchers in mind. Its emphasis is on understanding the physical properties of Si and similar tetrahedrally coordinated semiconductors. The explanations are based on physical insights. Each chapter is enriched by an extensive collection of tables of material parameters, figures, and problems. Many of these problems "lead the student by the hand" to arrive at the results. The major changes made in the fourth edition include: an extensive appendix about the important and by now well-established deep center known as the DX center, additional problems...

  8. Semiconductor materials for solar photovoltaic cells

    CERN Document Server

    Wong-Ng, Winnie; Bhattacharya, Raghu

    2016-01-01

    This book reviews the current status of semiconductor materials for conversion of sunlight to electricity, and highlights advances in both basic science and manufacturing.  Photovoltaic (PV) solar electric technology will be a significant contributor to world energy supplies when reliable, efficient PV power products are manufactured in large volumes at low cost.  Expert chapters cover the full range of semiconductor materials for solar-to-electricity conversion, from crystalline silicon and amorphous silicon to cadmium telluride, copper indium gallium sulfide selenides, dye sensitized solar cells, organic solar cells, and environmentally friendly copper zinc tin sulfide selenides. The latest methods for synthesis and characterization of solar cell materials are described, together with techniques for measuring solar cell efficiency. Semiconductor Materials for Solar Photovoltaic Cells presents the current state of the art as well as key details about future strategies to increase the efficiency and reduce ...

  9. Hybrid system of semiconductor and photosynthetic protein

    Science.gov (United States)

    Kim, Younghye; Shin, Seon Ae; Lee, Jaehun; Yang, Ki Dong; Nam, Ki Tae

    2014-08-01

    Photosynthetic protein has the potential to be a new attractive material for solar energy absorption and conversion. The development of semiconductor/photosynthetic protein hybrids is an example of recent progress toward efficient, clean and nanostructured photoelectric systems. In the review, two biohybrid systems interacting through different communicating methods are addressed: (1) a photosynthetic protein immobilized semiconductor electrode operating via electron transfer and (2) a hybrid of semiconductor quantum dots and photosynthetic protein operating via energy transfer. The proper selection of materials and functional and structural modification of the components and optimal conjugation between them are the main issues discussed in the review. In conclusion, we propose the direction of future biohybrid systems for solar energy conversion systems, optical biosensors and photoelectric devices.

  10. 76 FR 14688 - In the Matter of Certain Large Scale Integrated Circuit Semiconductor Chips and Products...

    Science.gov (United States)

    2011-03-17

    ... Commission's notice of investigation named several respondents including the following: Freescale Semiconductor Xiqing Integrated Semiconductor Manufacturing Site (``Freescale Xiqing'') of China; Freescale Semiconductor Innovation Center (``Freescale Innovation'') of China; Freescale Semiconductor Pte. Ltd. of...

  11. 75 FR 51843 - In the Matter of Certain Large Scale Integrated Circuit Semiconductor Chips and Products...

    Science.gov (United States)

    2010-08-23

    ... including the following: Freescale Semiconductor Xiqing Integrated Semiconductor Manufacturing Site (``Freescale Xiqing'') of China; Freescale Semiconductor Innovation Center (``Freescale Innovation'') of China; Freescale Semiconductor Pte. Ltd. (``Freescale Pte.'') of Singapore; and Premier Farnell Corporation d/b/a...

  12. Slow and fast light in semiconductor waveguides

    DEFF Research Database (Denmark)

    Mørk, Jesper; Hansen, Per Lunnemann; Xue, Weiqi

    2010-01-01

    transparency and coherent population oscillations. While electromagnetically induced transparency has been the most important effect in realizing slowdown effects in atomic gasses, progress has been comparatively slow in semiconductors due to inherent problems of fast dephasing times and inhomogeneous......Investigations of slow and fast light effects in semiconductor waveguides entail interesting physics and point to a number of promising applications. In this review we give an overview of recent progress in the field, in particular focusing on the physical mechanisms of electromagnetically induced...

  13. Spatial solitons in a pumped semiconductor resonator.

    Science.gov (United States)

    Taranenko, V B; Weiss, C O; Stolz, W

    2001-10-15

    Bright and dark spatial solitons are observed in an optically pumped semiconductor resonator. The pumping allows us to reduce considerably the light intensity necessary for the existence of the solitons and alleviates thermal load problems. Experiments are found to agree qualitatively with calculations based on a simple large-aperture semiconductor resonator model. The role of the signs of the absorptive and reactive nonlinearities in soliton existence is discussed in relation to the nonlinear resonance effect, the tilted-wave mechanism of pattern formation, and the sign of the population inversion.

  14. Quantum theory of electroabsorption in semiconductor nanocrystals.

    Science.gov (United States)

    Tepliakov, Nikita V; Leonov, Mikhail Yu; Baranov, Alexander V; Fedorov, Anatoly V; Rukhlenko, Ivan D

    2016-01-25

    We develop a simple quantum-mechanical theory of interband absorption by semiconductor nanocrystals exposed to a dc electric field. The theory is based on the model of noninteracting electrons and holes in an infinitely deep quantum well and describes all the major features of electroabsorption, including the Stark effect, the Franz-Keldysh effect, and the field-induced spectral broadening. It is applicable to nanocrystals of different shapes and dimensions (quantum dots, nanorods, and nanoplatelets), and will prove useful in modeling and design of electrooptical devices based on ensembles of semiconductor nanocrystals.

  15. Photon recycling semiconductor light-emitting diode

    Science.gov (United States)

    Guo, Xiaoyun; Graff, John W.; Schubert, E. F.; Karlicek, Robert F., Jr.

    2000-04-01

    A new white light emitting diode, the photon recycling semiconductor light emitting diode (PRS-LED) is demonstrated. The device consists of a GaInN/GaN LED emitting in the blue spectral range and an AlGaInP photon recycling semiconductor emitting at the complementary color. Thus the PRS-LED has two emission peaks, one in the blue and one in the amber wavelength range. The theoretical luminous performance of the PRS-LED exceeds 300 lm/W, higher than the performance of phosphor-based white LEDs.

  16. Self-organization in semiconductor physics.

    Science.gov (United States)

    Parisi, J

    1997-01-01

    Non-equilibrium dissipative systems from semiconductor physics have prevailed as a paradigmatic testing field for complex non-linear dynamics during the last decade. Especially, low-temperature impact ionization breakdown in extrinsic germanium crystals displays a variety of interesting nonlinear phenomena, such as spontaneous oscillations and filamentary patterns of the current flow. We report on recent experimental results concerning the interplay between spatial and temporal degrees of freedom during the onset of semiconductor breakdown. Quantitative evaluation of characteristic scaling properties supports the applicability of the model of self-organized criticality.

  17. III-V semiconductor materials and devices

    CERN Document Server

    Malik, R J

    1989-01-01

    The main emphasis of this volume is on III-V semiconductor epitaxial and bulk crystal growth techniques. Chapters are also included on material characterization and ion implantation. In order to put these growth techniques into perspective a thorough review of the physics and technology of III-V devices is presented. This is the first book of its kind to discuss the theory of the various crystal growth techniques in relation to their advantages and limitations for use in III-V semiconductor devices.

  18. Electron-Beam Controlled Semiconductor Switches

    Science.gov (United States)

    1993-11-02

    1987) 153-156. Mazzola , M.S., et al., "Investigation of a Photoconductive Closing and Opening Bulk U GaAs Semiconductor Switch," Proceedings of the...Un-doped GaAs or chromium doped GaAs has decay times of nanoseconds and less. Current scale is 40 mA div-1, time scale is 1000 ns divŕ. (M. Mazzola ...Semiconductor Switch," J. Appl. Phys. 63 (1988) 2460-2463. [5] Mazzola , M., Schoenbach, K., Lakdawala, V., Germer, R., Loubriel, M., and Zutavern, F

  19. Progress in 2D semiconductor optoelectronics

    Science.gov (United States)

    Majumdar, Arka; Fryett, Taylor; Liu, Chang-Hua; Zheng, Jiajiu; Wu, Sanfeng; Rivera, Pasqual; Syler, Kyle; Clark, Genevieve; Xu, Xiaodong

    2017-05-01

    2D semiconductors have recently emerged as promising optoelectronic materials, with high quantum efficiency of photoemission, absorption and nonlinear optical properties. With significant progress in understanding the material science of these atomically thin materials, and building devices with stand-alone monolayer materials, it is an opportune time to integrate these materials with existing optoelectronic platform to realize the full potential of the 2D materials. Here, we highlight our recent progress in 2D semiconductor integrated with nanophotonic resonators. Specifically, we report the operation of an optically pumped laser, cavity enhanced electroluminescence and cavity enhanced second harmonic generation.

  20. Carrier scattering in metals and semiconductors

    CERN Document Server

    Gantmakher, VF

    1987-01-01

    The transport properties of solids, as well as the many optical phenomena in them are determined by the scattering of current carriers. ``Carrier Scattering in Metals and Semiconductors'' elucidates the state of the art in the research on the scattering mechanisms for current carriers in metals and semiconductors and describes experiments in which these mechanisms are most dramatically manifested.The selection and organization of the material is in a form to prepare the reader to reason independently and to deal just as independently with available theoretical results and experimental

  1. Novel Capacitance Measurements in Copper Indium Gallium Diselenide Alloys: Final Subcontract Report, 1 July 1999--31 August 2003

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D. C.

    2004-05-01

    This subcontract report describes the University of Oregon's objectives to measure the electronic properties of the copper indium/gallium diselenide alloys using several well-developed capacitance techniques appropriate for probing materials with a continuous distribution of semiconducting gap electronic energy states. We applied a new synthetic method to the production of CIGS alloys, namely, the modulated elemental reactant method. To form CIGS by this method, alternating layers of Cu:In:Se and Cu:Ga:Se composites, each less than 100 thick, were evaporated in sequence and then annealed at low temperature. A second focus was to test and develop junction capacitance methods to better understand the electronic properties in CIGS material and establish a relationship of those properties to specific device performance parameters. The primary methods employed were transient photocapacitance (TPC) spectroscopy and drive-level capacitance profiling (DLCP). Finally, we extended our characterization studies to four CuIn1-xAlxSe2 (CIAS) samples, also supplied by IEC. Our photocapacitance and DLCP measurements on these CIAS samples indicated that for a sample with 13 at.% Al (having a bandgap of nearly 1.2 eV), the electronic properties were essentially identical to those in CIGS samples with 26 at.% Ga.

  2. Cast Polycrystalline Photovoltaic Module Manufacturing Technology Improvements; Final Subcontract Report, 8 December 1993-30 April 1998

    Energy Technology Data Exchange (ETDEWEB)

    Wohlgemuth, J.

    1999-06-16

    This report summarizes work performed by Solarex, A Business Unit of Amoco/Enron Solar, under this subcontract. Among the accomplishments during the program are the following: Converting all of the production casting stations to increase ingot size, operating them at equivalent yields and cell efficiencies, and thus doubling the casting capacity at a 20% lower cost than the cost of new equipment. Developing a wire-saw process and transferring the process to production; as a result, more than 80% of wafering is now done using wire saws, at higher yields and lower costs than achieved on the internal diameter saws. Developing an aluminum paste back-surface field (BSF) process to increase cell efficiency by 5%; researchers also designed, procured, and transferred to manufacturing a fully automated printing system to produce the BSF cells. Fabricating 15.2-cm by 15.2-cm polycrystalline silicon solar cells and building modules using these cells. Modifying the module assembly area to increase capacity by a factor of three. Implementing a single-layer Tedlar backsheet that reduced backsheet cost by $0.50/ft2. Selecting, testing, and qualifying a low-cost (< $1.00 per module) electrical termination system. Qualifying the structure and adhesive system for mounting frameless modules and using the system to build several large arrays.

  3. PV Inverter Products Manufacturing and Design Improvements for Cost Reduction and Performance Enhancements: Final Subcontract Report, November 2003 (Revised)

    Energy Technology Data Exchange (ETDEWEB)

    West, R.

    2004-04-01

    The specific objectives of this subcontracted development work by Xantrex Technology Inc. were to: (1) Capture the newest digital signal processor (DSP) technology to create high-impact,''next generation'' power conversion equipment for the PV industry; (2) Create a common resource base for three PV product lines. This standardized approach to both hardware and software control platforms will provide significant market advantage over foreign competition; (3) Achieve cost reductions through increased volume of common components, reduced assembly labor, and the higher efficiency of producing more products with fewer design, manufacturing, and production test variations; (4) Increase PV inverter product reliability. Reduce inverter size, weight and conversion losses. The contract goals were to achieve an overall cost reduction of 10% to 20% for the three inverters and with no compromise in performance. The cost of the 10-kW inverter was reduced by 56%, and the cost of the 25-kW inverter was reduced by 53%. The 2.5-kW inverter has no basis for comparison, but should benefit equally from this design approach. Not only were the contract cost reduction goals exceeded by a wide margin, but the performance and reliability of the products were also enhanced. The conversion efficiency improvement, as reflected in the 50% conversion loss reduction, adds significant value in renewable energy applications. The size and weight reductions also add value by providing less cumbersome product solutions for system designers.

  4. Semiconductor surface physics research in the Space Shuttle orbit

    Energy Technology Data Exchange (ETDEWEB)

    Lindau, I.; Spicer, W.E.

    1977-11-01

    The prospects for surface physics research on semiconductors with the Space Shuttle are summarized. The effect of residual gases and solar radiation outside the Shuttle on the semiconductor-surface electronic properties are assessed.

  5. Annual Statistical Supplement, 2002

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2002 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  6. Annual Statistical Supplement, 2003

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2003 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  7. Annual Statistical Supplement, 2001

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2001 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  8. Annual Statistical Supplement, 2010

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2010 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  9. Annual Statistical Supplement, 2007

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2007 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  10. Annual Statistical Supplement, 2016

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2016 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  11. Annual Statistical Supplement, 2000

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2000 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  12. Annual Statistical Supplement, 2008

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2008 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  13. Annual Statistical Supplement, 2006

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2006 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  14. Annual Statistical Supplement, 2005

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2005 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  15. Annual Statistical Supplement, 2015

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2015 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  16. Annual Statistical Supplement, 2004

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2004 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  17. Annual Statistical Supplement, 2014

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2014 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  18. Annual Statistical Supplement, 2009

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2009 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  19. Annual Statistical Supplement, 2011

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2011 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  20. Annual report 1998; Rapport annuel 1998

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-01

    Associated to the CEA, the CEA-Industry subsidiaries and the whole Group submit a very satisfying financial, economic and technological accounting which able to play a major role in international cooperations and to satisfy the shareholders. To illustrate these results, this annual report presents the activities of the CEA-Industry group during the year 1998. It is divided in eight chapters. The first six chapters gives general information and main financial data on respectively the CEA-Industry Group profile, economics, the fuel cycle, the nuclear power plants, the nuclear medicine and the semiconductors. The chapter 7 deals with the financial results of the fiscal year 1998 and the last chapter is devoted to the management report of the administration council. (A.L.B.)

  1. Suitability of integrated protection diodes from diverse semiconductor technologies

    NARCIS (Netherlands)

    Wanum, M. van; Lebouille, T.T.N.; Visser, G.C.; Vliet, F.E. van

    2009-01-01

    In this article diodes from three different semiconductor technologies are compared based on their suitability to protect a receiver. The semiconductor materials involved are Silicon, Gallium Arsenide and Gallium Nitride. The diodes in the diverse semiconductor technologies themselves are close in

  2. Point defects in group IV semiconductors

    CERN Document Server

    Pizzini, S

    2017-01-01

    Aim of this book is to focus on the properties of defects in semiconductors of the fourth group under a physico-chemical approach, capable to demonstrate whether the full acknowledgement of their chemical nature could account for several problems encountered in practice or would suggest further experimental or theoretical accomplishments.

  3. Physics of semiconductors in high magnetic fields

    CERN Document Server

    Miura, Noboru

    2008-01-01

    This book summarizes most of the fundamental physical phenomena which semiconductors and their modulated structures exhibit in high magnetic fields. Readers can learn not only the basic theoretical background but also the present state of the art from the most advanced data in this rapidly growing research area.

  4. SCOOP - Semiconductor COmponents for Optical signal Processing

    DEFF Research Database (Denmark)

    Mørk, Jesper; Yvind, Kresten; Oxenløwe, Leif Katsuo

    2001-01-01

    Opto-electronic semiconductor devices operating at very high bitrates play a central role in the continued expansion of the transmission capacity of optical communication systems. A number of different devices based on quantum well structures have been manufactured within the framework of the nat...

  5. Opportunities and Risks in Semiconductor Metrology

    Science.gov (United States)

    Borden, Peter

    2005-09-01

    New metrology opportunities are constantly emerging as the semiconductor industry attempts to meet scaling requirements. The paper summarizes some of the key FEOL and BEOL needs. These must be weighed against a number of considerations to ensure that they are good opportunities for the metrology equipment supplier. The paper discusses some of these considerations.

  6. Ballistic transport in semiconductor nanostructures: From quasi ...

    Indian Academy of Sciences (India)

    By suitable design it is possible to achieve quasi-ballistic transport in semiconductor nanostructures over times up to the ps-range. Monte-Carlo simulations reveal that under these conditions phase-coherent real-space oscillations of an electron ensemble, generated by fs-pulses become possible in wide potential wells.

  7. Impact of nano particles on semiconductor manufacturing

    NARCIS (Netherlands)

    Wali, F.; Knotter, D.M.; Kuper, F.G.

    2008-01-01

    Semiconductor industry faces a continuous challenge to decrease the transistor size as well as to increase the yield by eliminating defect sources. One of the sources of particle defects is ultra pure water used in different production tools at different stages of processing. In this paper, particle

  8. New semiconductor materials for magnetoelectronics at room ...

    Indian Academy of Sciences (India)

    Unknown

    inherent advantage of magnetoelectronics over electronics is the fact that magnet tend to stay magnetized for long. Hence this arises interest in industries to replace the semiconductor-based components of computer with mag- netic ones, starting from RAM. The new magnetic RAM will retain data even when the computer is ...

  9. Competing interactions in semiconductor quantum dots

    NARCIS (Netherlands)

    van den Berg, R.; Brandino, G.P.; El Araby, O.; Konik, R.M.; Gritsev, V.; Caux, J.S.

    2014-01-01

    We introduce an integrability-based method enabling the study of semiconductor quantum dot models incorporating both the full hyperfine interaction as well as a mean-field treatment of dipole-dipole interactions in the nuclear spin bath. By performing free-induction decay and spin-echo simulations

  10. Automated semiconductor vacuum chemical vapor deposition facility

    Science.gov (United States)

    1982-01-01

    A semiconductor vacuum chemical vapor deposition facility (totally automatic) was developed. Wafers arrived on an air track, automatically loaded into a furnace tube, processed, returned to the track, and sent on to the next operation. The entire process was controlled by a computer.

  11. Semiconductor nanowire optical antenna solar absorbers.

    Science.gov (United States)

    Cao, Linyou; Fan, Pengyu; Vasudev, Alok P; White, Justin S; Yu, Zongfu; Cai, Wenshan; Schuller, Jon A; Fan, Shanhui; Brongersma, Mark L

    2010-02-10

    Photovoltaic (PV) cells can serve as a virtually unlimited clean source of energy by converting sunlight into electrical power. Their importance is reflected in the tireless efforts that have been devoted to improving the electrical and structural properties of PV materials. More recently, photon management (PM) has emerged as a powerful additional means to boost energy conversion efficiencies. Here, we demonstrate an entirely new PM strategy that capitalizes on strong broad band optical antenna effects in one-dimensional semiconductor nanostructures to dramatically enhance absorption of sunlight. We show that the absorption of sunlight in Si nanowires (Si NWs) can be significantly enhanced over the bulk. The NW's optical properties also naturally give rise to an improved angular response. We propose that by patterning the silicon layer in a thin film PV cell into an array of NWs, one can boost the absorption for solar radiation by 25% while utilizing less than half of the semiconductor material (250% increase in the light absorption per unit volume of material). These results significantly advance our understanding of the way sunlight is absorbed by one-dimensional semiconductor nanostructures and provide a clear, intuitive guidance for the design of efficient NW solar cells. The presented approach is universal to any semiconductor and a wide range of nanostructures; as such, it provides a new PV platform technology.

  12. UK semiconductor tracker parts head for CERN

    CERN Multimedia

    Holland, Colin

    2005-01-01

    The last of the 4 barrels that make up the central part of the Semiconductor Tracker (SCT), the heart of the biggest physics collaboration in the world have left Oxford for its new home at the European Particle Physics Laboratory, CERN, near Geneva

  13. Theory of mode-locked semiconductor lasers.

    NARCIS (Netherlands)

    Leegwater, J.A.

    1996-01-01

    We present a theoretical study of semiconductor mode-locked lasers at a phenomenological level. We use the slow absorber model of New and Haus, but extend the analysis by taking into account the shift in the gain maximum due to the changing number of carriers. In our analysis of the resulting

  14. Ultrafast THz Saturable Absorption in Semiconductors

    DEFF Research Database (Denmark)

    Turchinovich, Dmitry; Hoffmann, Matthias C.

    2011-01-01

    We demonstrate THz saturable absorption in n-doped semiconductors GaAs, GaP, and Ge in a nonlinear THz time-domain spectroscopy experiment. Saturable absorption is caused by sample conductivity modulation due to electron heating and satellite valley scattering in the field of a strong THz pulse....

  15. Ultranarrow polaritons in a semiconductor microcavity

    DEFF Research Database (Denmark)

    Jensen, Jacob Riis; Borri, Paola; Langbein, Wolfgang

    2000-01-01

    We have achieved a record high ratio (19) of the Rabi splitting (3.6 meV) to the polariton linewidth (190 mu eV), in a semiconductor lambda microcavity with a single 25 nm GaAs quantum well at the antinode. The narrow polariton lines are obtained with a special cavity design which reduces...

  16. Niobium Nitride Josephson Devices with Semiconductor Barriers.

    Science.gov (United States)

    1981-09-01

    impedance of the semiconductor side of the device.17 (An exception is the silicon membrane structures of Huang and Van Duzer . 2) In our devices this...and T. Van Duzer , Appl. Phys. Lett. 25, 753 (1974). 3. M. Schyfter, J. Maah-Sango, N. Ralez, R. Rubz, B. T. Alrich, and T. Van Duzer , IEEE Trans

  17. Neutron Detection with Cryogenics and Semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    bell, Z.W.; Carpenter, D.A.; Cristy, S.S.; Lamberti, V.E.

    2005-03-10

    The common methods of neutron detection are reviewed with special attention paid to the application of cryogenics and semiconductors to the problem. The authors' work with LiF- and boron-based cryogenic instruments is described as well as the use of CdTe and HgI{sub 2} for direct detection of neutrons.

  18. Optical Properties of Semiconductor Quantum Dots

    NARCIS (Netherlands)

    Perinetti, U.

    2011-01-01

    This thesis presents different optical experiments performed on semiconductor quantum dots. These structures allow to confine a small number of electrons and holes to a tiny region of space, some nm across. The aim of this work was to study the basic properties of different types of quantum dots

  19. A hybrid semiconductor-glass waveguide laser

    NARCIS (Netherlands)

    Fan, Youwen; Oldenbeuving, Ruud; Klein, E.J.; Lee, Christopher James; Song, H.; Khan, M.R.H.; Offerhaus, Herman L.; van der Slot, Petrus J.M.; Boller, Klaus J.; Mackenzie, J.I.; Jelinkova, H.; Taira, T.; Ahmed, M.A.

    2014-01-01

    abstract .We report on a novel type of laser in which a semiconductor optical amplifier (SOA) receives frequency-selective feedback from a glass-waveguide circuit. The laser we present here is based on InP for operation in the 1.55 μm wavelength range. The Si3N4/SiO2 glass waveguide circuit

  20. A hybrid semiconductor-glass waveguide laser

    NARCIS (Netherlands)

    Fan, Y.; Oldenbeuving, R.M.; Klein, E.J.; Lee, C.J.; Song, H.; Khan, M.R.H.; Offerhaus, H.L.; Van der Slot, P.J.M.; Boller, K.J.

    2014-01-01

    We report on a novel type of laser in which a semiconductor optical amplifier (SOA) receives frequency-selective feedback from a glass-waveguide circuit. The laser we present here is based on InP for operation in the 1.55 µm wavelength range. The Si3N4/SiO2 glass waveguide circuit comprises two

  1. Emission and Absorption Entropy Generation in Semiconductors

    DEFF Research Database (Denmark)

    Reck, Kasper; Varpula, Aapo; Prunnila, Mika

    2013-01-01

    materials due to emission and absorption of electromagnetic radiation. It is shown that the emission and absorption entropy generation reduces the fundamental limit on the efficiency of any semiconductor solar cell even further than the Landsberg limit. The results are derived from purely thermodynamical...

  2. Method for manufacturing a semiconductor device

    NARCIS (Netherlands)

    Ishihara, R.; Baiano, A.

    2009-01-01

    The invention relates to a method for manufacturing a semiconductor device on a substrate provided with a silicon-oxide layer, by forming at least one hole in said silicon-oxide layer and depositing on said silicon-oxide layer an amorphous silicon-film which fills said at least one hole and covers a

  3. The Quantum Boltzmann Equation in Semiconductor Physics

    OpenAIRE

    Snoke, D. W.

    2010-01-01

    The quantum Boltzmann equation, or Fokker-Planck equation, has been used to successfully explain a number of experiments in semiconductor optics in the past two decades. This paper reviews some of the developments of this work, including models of excitons in bulk materials, electron-hole plasmas, and polariton gases.

  4. Bipolar magnetic semiconductor in silicene nanoribbons

    Energy Technology Data Exchange (ETDEWEB)

    Farghadan, Rouhollah, E-mail: rfarghadan@kashanu.ac.ir

    2017-08-01

    Highlights: • A new electronic phase for silicene nanoribbon in the presence of electric and magnetic fields. • Bipolar magnetic semiconductor with controllable spin-flip and spin-conserved gaps in silicene. • Robust bipolar magnetic semiconductor features in a rough silicene. • Perfect and reversible spin polarization in silicene nanoribbon junctions. - Abstract: A theoretical study was presented on generation of spin polarization in silicene nanoribbons using the single-band tight-binding approximation and the non-equilibrium Green’s function formalism. We focused on the effect of electric and exchange magnetic fields on the spin-filter capabilities of zigzag-edge silicene nanoribbons in the presence of the intrinsic spin-orbit interaction. The results show that a robust bipolar magnetic semiconductor with controllable spin-flip and spin-conserved gaps can be obtained when exchange magnetic and electric field strengths are both larger than the intrinsic spin-orbit interaction. Therefore, zigzag silicene nanoribbons could act as bipolar and perfect spin filter devices with a large spin-polarized current and a reversible spin polarization in the vicinity of the Fermi energy. We also investigated the effect of edge roughness and found that the bipolar magnetic semiconductor features are robust against edge disorder in silicene nanoribbon junctions. These results may be useful in multifunctional spin devices based on silicene nanoribbons.

  5. Tunneling of electrons through semiconductor superlattices

    Indian Academy of Sciences (India)

    Unknown

    The SSL we have considered is Ga0⋅7Al0⋅3As–GaAs which has been drawing considerable attention during the recent past on account of some typical features of its band structure. We have indicated how our results would help fabrication of ultra high speed devices. Keywords. Semiconductor superlattices; tunneling. 1.

  6. Semiconductor detectors with proximity signal readout

    Energy Technology Data Exchange (ETDEWEB)

    Asztalos, Stephen J. [XIA, LLC, Hayward, CA (United States)

    2014-01-30

    Semiconductor-based radiation detectors are routinely used for the detection, imaging, and spectroscopy of x-rays, gamma rays, and charged particles for applications in the areas of nuclear and medical physics, astrophysics, environmental remediation, nuclear nonproliferation, and homeland security. Detectors used for imaging and particle tracking are more complex in that they typically must also measure the location of the radiation interaction in addition to the deposited energy. In such detectors, the position measurement is often achieved by dividing or segmenting the electrodes into many strips or pixels and then reading out the signals from all of the electrode segments. Fine electrode segmentation is problematic for many of the standard semiconductor detector technologies. Clearly there is a need for a semiconductor-based radiation detector technology that can achieve fine position resolution while maintaining the excellent energy resolution intrinsic to semiconductor detectors, can be fabricated through simple processes, does not require complex electrical interconnections to the detector, and can reduce the number of required channels of readout electronics. Proximity electrode signal readout (PESR), in which the electrodes are not in physical contact with the detector surface, satisfies this need.

  7. Dispersion-induced nonlinearities in semiconductors

    DEFF Research Database (Denmark)

    Mørk, Jesper; Mecozzi, A.

    2002-01-01

    A dispersive and saturable medium is shown, under very general conditions, to possess ultrafast dynamic behaviour due to non-adiabatic polarisation dynamics. Simple analytical expressions relating the effect to the refractive index dispersion of a semiconductor ire derived and the magnitude...

  8. Electrostatic model of semiconductor nanoparticles trapped in ...

    Indian Academy of Sciences (India)

    A simple electrostatic model is applied to study the solvation energy and localization energy to inorganic semiconductor nanocrystallites trapped in polymer and ion conducting ... In the single charge configuration, the dielectric constant of the medium has been identified as the selection criteria for hosting the nanoparticles.

  9. Revenue sharing in semiconductor industry supply chain ...

    Indian Academy of Sciences (India)

    This paper defines cooperation as the process of coordinating the objectives and activities of supply chain (SC) members. It also focuses on cooperation as a solution for hybrid coordination mechanism to form the basis for semiconductor industry supply chain management. In the complex and competitive environment of ...

  10. Testing of modern semiconductor memory structures

    NARCIS (Netherlands)

    Gaydadjiev, G.N.

    2007-01-01

    In this thesis, we study the problem of faults in modern semiconductor memory structures and their tests. According to the 2005 ITRS, the systems on chip (SoCs) are moving from logic and memory balanced chips to more memory dominated devices in order to cope with the increasing application

  11. Scientific Description of Summer Semiconductor Program

    Science.gov (United States)

    1991-03-02

    EE/CS 3-180 9:30 am Carlo Cercignani Methods of the kinetic theory of gases relevant Politecuico di Milsao to the kinetic models for semiconductors...Pittsburgh Jul 15-Aug 9 Cercignani , Carlo Politecnico di Milano Jul 21-Aug 3 Cole, Dan IBM GPD Jul 24-Aug 1 Cole, J-dian Rensselaer Polytechnic Institute

  12. Semiconductor devices for all-optical regeneration

    DEFF Research Database (Denmark)

    Öhman, Filip; Bischoff, Svend; Tromborg, Bjarne

    2003-01-01

    We review different implementations of semiconductor devices for all-optical regeneration. A general model will be presented for all-optical regeneration in fiber links, taking into consideration the trade-off between non-linearity and noise. Furthermore we discuss a novel regenerator type, based...

  13. Many electron effects in semiconductor quantum dots

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 26; Issue 1. Many electron effects in ... Semiconductor quantum dots (QDs) exhibit shell structures, very similar to atoms. Termed as 'artificial atoms' by some, ... Our calculations have been performed in a three-dimensional quantum dot. We have carried out a study of ...

  14. Picosecond Nonlinear Resonant Interactions in Semiconductors.

    Science.gov (United States)

    1986-03-01

    1985). 3. "Electron-Hole Recombination Spectra and Kinetics in PbTc/PbEuTcSc Multiple Quamtum Wells", W. Goltsos, J. Nakahara, A. V. Nurmikko, and D...Partin, Proc. Int. Conf. Modulated Semiconductor Structures, Kyoto, Surface Science (in press). 4. "Optical Bandgap and Magneto-Optical Effects in (Pb,Eu

  15. A Semiconductor Nanowire-Based Superconducting Qubit

    DEFF Research Database (Denmark)

    Larsen, T. W.; Petersson, K. D.; Kuemmeth, F.

    2015-01-01

    We introduce a hybrid qubit based on a semiconductor nanowire with an epitaxially grown superconductor layer. Josephson energy of the transmon-like device ("gatemon") is controlled by an electrostatic gate that depletes carriers in a semiconducting weak link region. Strong coupling to an on...

  16. All optical regeneration using semiconductor devices

    DEFF Research Database (Denmark)

    Mørk, Jesper; Öhman, Filip; Tromborg, Bjarne

    All-optical regeneration is a key functionality for implementing all-optical networks. We present a simple theory for the bit-error-rate in links employing all-optical regenerators, which elucidates the interplay between the noise and and nonlinearity of the regenerator. A novel device structure ...... is analyzed, emphasizing general aspects of active semiconductor waveguides....

  17. Electron Spins in Semiconductor Quantum Dots

    NARCIS (Netherlands)

    Hanson, R.

    2005-01-01

    This thesis describes a series of experiments aimed at understanding and controlling the behavior of the spin degree of freedom of single electrons, confined in semiconductor quantum dots. This research work is motivated by the prospects of using the electron spin as a quantum bit (qubit), the basic

  18. Semiconductor applications of plasma immersion ion implantation ...

    Indian Academy of Sciences (India)

    Many semiconductor integrated circuit manufacturing processes require high dose of implantation at very low energies. Conventional beam line ion implantation system suffers from low beam current at low energies, therefore, cannot be used economically for high dose applications. Plasma immersion ion implantation (PIII) ...

  19. Electrostatic model of semiconductor nanoparticles trapped in ...

    Indian Academy of Sciences (India)

    Abstract. A simple electrostatic model is applied to study the solvation energy and localization energy to inorganic semiconductor nanocrystallites trapped in polymer and ion conducting polymer electrolytes. The effective mass approximation has been applied to the system. In the single charge configuration, the dielectric ...

  20. Trap level spectroscopy in amorphous semiconductors

    CERN Document Server

    Mikla, Victor V

    2010-01-01

    Although amorphous semiconductors have been studied for over four decades, many of their properties are not fully understood. This book discusses not only the most common spectroscopic techniques but also describes their advantages and disadvantages.Provides information on the most used spectroscopic techniquesDiscusses the advantages and disadvantages of each technique