Download or read book The Diffusivity and Doping Properties of Indium in Cadmium Telluride written by E. Watson and published by . This book was released on 1979 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Doping Studies of Cadmium Telluride Cadmium Magnesium Telluride and CdTe CdMgTe Double Heterostructures Grown Using Molecular Beam Epitaxy written by Olanrewaju Sunday Ogedengbe and published by . This book was released on 2017 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: CdTe is one of the leading materials used in thin-film photovoltaic (PV) devices due to some of its basic properties such as its ability to permit both n- and p-type doping, its relatively high absorption coefficient for photons in the visible range, and its direct band gap of 1.514 eV at room temperature, which is near the optimal band gap for solar energy conversion. Despite the near optimal band gap, the highest power conversion efficiency in a CdTe solar cell to date, achieved using polycrystalline CdTe, stands at 21%. This is far less than the Shockley-Queisser limit, which is about 32% for a single-junction cell under AM 1.5 illumination condition. Research efforts have shown that short circuit current (Jsc) is near its theoretical limit, implying that strategies to improve cell efficiency will have to be contingent on improving open-circuit voltage (Voc) and fill factor. Heavy doping has the potential to improve Voc. There is also evidence that inclusion of a Cd1-xMgxTe barrier in a solar cell structure may improve open circuit voltage, and, ultimately, cell efficiency. Doped and undoped CdTe layers were grown by molecular beam epitaxy (MBE). Secondary ion mass spectrometry (SIMS) characterization was used to measure dopant concentration, while Hall measurement and the capacitance-voltage technique were used for determining carrier concentration. Photoluminescence intensity (PL-I) and time-resolved photoluminescence (TRPL) techniques were used for optical characterization. The incorporation and limits of iodine and arsenic dopants in CdTe were studied. Maximum n-type carrier concentrations of 7.4x1018 cm-3 for iodine-doped CdTe and 3x1017 cm-3 for iodine-doped Cd0.65Mg0.35Te were achieved. Studies suggest that electrically active doping with iodine is limited with dopant concentration much above these values. Dopant activation of about 80% was observed in most of the iodine-doped CdTe samples. The estimated activation energy is about 6 meV for CdTe and the value for Cd0.65Mg0.35Te is about 58 meV. Iodine-doped CdTe samples exhibit long lifetimes with no evidence of photoluminescence degradation with doping as high as 2x1018 cm-3 while indium shows substantial non-radiative recombination at carrier concentrations above 5x1016 cm-3. Also, maximum p-type carrier concentration of 2x1016 cm-3 for arsenic-doped CdTe was achieved. Dopant activation greater than 20% was observed in most of the arsenic-doped CdTe samples. The process compatibility of iodine and magnesium in CdTe was evaluated for the solar cell device. Iodine was shown to be thermally stable in CdTe at temperatures up to 600oC and magnesium showed a slow diffusion at 500oC. Doped CdTe structures were used to make solar cell device structures, where open circuit voltage up to 880 mV and fill factor up to ~60% were measured.
Download or read book Properties of Narrow Gap Cadmium based Compounds written by Peter Capper and published by IET. This book was released on 1994 with total page 648 pages. Available in PDF, EPUB and Kindle. Book excerpt: This highly structured volume contains sections on growth and device aspects of mercury cadmium telluride (MCT).
Download or read book Doping and Diffusion in HgCdTe written by and published by . This book was released on 1991 with total page 71 pages. Available in PDF, EPUB and Kindle. Book excerpt: The structural properties and electrical activity of impurities (indium, arsenic, antimony) and self-interstitials (mercury, cadmium, tellurium) in CdTe and HgCdTe alloys have been studied by theoretical and computer calculations, The problems addressed included: - the source of the midgap tunneling levels in Hg-rich HgCdTe, - the cause of electrical inactivity in In- doped CdTe grown by non-photoassisted molecular beam epitaxy (MBE), - identification of paths for impurity and self-diffusion, - the effects of lattice distortion on defect properties and interaction.
Download or read book Physics and Chemistry of Mercury Cadmium Telluride and Novel IR Detector Materials written by David G. Seiler and published by American Institute of Physics. This book was released on 1991 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Diffusion and Defect Data written by and published by . This book was released on 1999 with total page 948 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mercury Cadmium Telluride written by Peter Capper and published by John Wiley & Sons. This book was released on 2011-06-20 with total page 610 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mercury cadmium telluride (MCT) is the third most well-regarded semiconductor after silicon and gallium arsenide and is the material of choice for use in infrared sensing and imaging. The reason for this is that MCT can be ‘tuned’ to the desired IR wavelength by varying the cadmium concentration. Mercury Cadmium Telluride: Growth, Properties and Applications provides both an introduction for newcomers, and a comprehensive review of this fascinating material. Part One discusses the history and current status of both bulk and epitaxial growth techniques, Part Two is concerned with the wide range of properties of MCT, and Part Three covers the various device types that have been developed using MCT. Each chapter opens with some historical background and theory before presenting current research. Coverage includes: Bulk growth and properties of MCT and CdZnTe for MCT epitaxial growth Liquid phase epitaxy (LPE) growth Metal-organic vapour phase epitaxy (MOVPE) Molecular beam epitaxy (MBE) Alternative substrates Mechanical, thermal and optical properties of MCT Defects, diffusion, doping and annealing Dry device processing Photoconductive and photovoltaic detectors Avalanche photodiode detectors Room-temperature IR detectors
Download or read book Index to Theses Accepted for Higher Degrees by the Universities of Great Britain and Ireland and the Council for National Academic Awards written by and published by . This book was released on 1982 with total page 816 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1976 with total page 658 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Metals Abstracts written by and published by . This book was released on 1983 with total page 1058 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1991 with total page 602 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book U S Government Research Development Reports written by and published by . This book was released on 1966-11 with total page 1014 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Solar Energy Update written by and published by . This book was released on 1979-04 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cadmium Telluride written by Samuel Bigbee-Hansen and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the pursuit of creating efficient CdTe p-n homojunctions, we developed iodine (I) n-type doped CdTe using Cadmium Iodide (CdI2) as a dopant in varying concentrations (1018 cm-3, 1019 cm-3 and 1020 atoms℗ʺcm-3 target concentrations) in CdTe. Iodide doped crystals were grown using a Modified Vertical Bridgman furnace (MVB). Single crystals were characterized using XRD (X-Ray Diffraction), Hall effect, IR (Infrared) Microscopy, UV-VIS-NIR (Ultraviolet-Visible-Near infrared Spectroscopy) and FTIR (Fourier Transform Infrared Spectroscopy). Partners at the National Renewable Energy Laboratory (NREL) also provided data for Hall Effect and Two Photon Excitation Time Resolved Photoluminescence (2PE TRPL) of wafers and films. Photoluminescence mapping (PL mapping) was obtained from Klar scientific, and glow discharge mass spectrometry (GDMS) for purity and final doping concentration was obtained from the National Research Council Canada. Due to poor carrier properties in the crystals as-grown, two annealing treatments were explored, in either tellurium or cadmium vapor. Homojunctions were made at NREL by depositing n-type films from these crystals on p-type single crystals, CdTe:P grown and WSU. The n-type films were created using the close-space sublimation epitaxy (CSSE) process. Herein is reported the results of the grown CdTe:I crystals and, to a lesser extent, the properties of the CdTe:I thin films formed by CSSE.
Download or read book Catalog of Technical Reports written by United States. Dept. of Commerce. Office of Technical Services and published by . This book was released on with total page 600 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of Optoelectronic Device Modeling and Simulation written by Joachim Piprek and published by CRC Press. This book was released on 2017-10-12 with total page 887 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides a comprehensive survey of fundamental concepts and methods for optoelectronic device modeling and simulation. Gives a broad overview of concepts with concise explanations illustrated by real results. Compares different levels of modeling, from simple analytical models to complex numerical models. Discusses practical methods of model validation. Includes an overview of numerical techniques.
Download or read book X ray and Gamma ray Detectors and Applications IV written by Ralph B. James and published by SPIE-International Society for Optical Engineering. This book was released on 2002 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt:
