Download or read book Electrical Properties of Grain Boundaries in Low Doped Polycrystalline Materials with Applications to Detectors written by Mazharul Huq Chowdhury and published by . This book was released on 2010 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polycrystalline materials are widely used in large area electronic devices such as flat panel x-ray image detectors, and solar cells due to their suitability to deposit over large area at low cost. The performance of polycrystalline-based flat panel detectors are showing encouraging results (good sensitivity, good resolution and acceptable dark current) and give possibility to replace existing x-ray film/screen cassette. Therefore large area polycrystalline based flat panel detectors have opened new clinical possibilities and the polycrystalline solar cells give the opportunity of manufacturing low cost photovoltaic cells. Consequently, active research has been carried out to find out suitable polycrystalline materials (e.g. HgI2, CdTe, CdZnTe, PbI2, PbO etc) for various large area applications. However a polycrystalline material is composed of micro crystallites joined together by grain boundaries (complex structure, consisting of a few atomic layers of disordered atoms) which posses trap centers for charge carriers. Therefore, grain boundaries can trap a large amount of charges during detector operation. A potential barrier for drifting carriers may exist at the grain boundary, which controls the carrier mobility. Moreover, the performance of these polycrystalline detectors are affected due to the polarization phenomena (any change in the performance of the detector after the detector biasing) under applied bias. Therefore, in this research work, an analytical model is developed to study the electrical properties (electric field and potential distributions, potential barrier height, and polarization phenomenon) of polycrystalline materials at different doping levels for detector and solar cell applications by considering an arbitrary amount of grain boundary charge and a finite width of grain boundary region. The general grain boundary model is also applicable to highly doped polycrystalline materials. The electric field and potential distributions are obtained by solving the Poisson's equation in both depleted grains and grain boundary regions. The electric field and potential distributions across the detector are analyzed under various doping, trapping and applied biases. The electric field collapses, i.e., a nearly zero average electric field region exists in some part of the biased detector at high trapped charge densities at the grain boundaries. The model explains the conditions of existence of a zero average field region, i.e., it explains the polarization mechanisms in polycrystalline materials. The potential barrier at the grain boundary exists if the electric field changes its sign at the opposite side of the grain boundary. The potential barrier does not exist in all grain boundaries in the low doped polycrystalline detector and it never exists in intrinsic polycrystalline detectors under applied bias condition provided there is no charge trapping in the grain.
Download or read book Polycrystalline Semiconductors written by Hans J. Möller and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 399 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book summarizes the most recent aspects of polycrystalline semiconductors as presented at the conference Polycrystalline Semiconductors - Grain Boundaries and Interfaces. It contains 12 review articles on selected topics written by experts in their fields and 41 complementary contributed papers. The structure, chemistry and physics of grain boundaries and other interfaces are experimentally and theoretically studied. Aspects of the technologically important polycrystalline silicon are discussed in detail. Also covered are other polycrystalline semiconductors, germanium and compound semiconductors, that are currently of interest in fundamental research and in the technology of solar cells and thin film devices. Anyone interested in polycrystalline semiconductors will be able to use this comprehensive collection to advantage. It also suggests directions for new research and development.
Download or read book Ferroelectric Materials and Their Applications to Sensors written by A. Bhalla and published by CRC Press. This book was released on 1988 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Properties of Grain Boundaries in YBa2Cu3O7 d written by James Ransley and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Grain boundaries form the basis of an important Josephson junction technology in the cuprates and also limit the superconducting critical currents attainable in practical, polycrystalline materials. An improved understanding of these defects is therefore important for applications. The status of the current understanding of cuprate grain boundaries is summarised and experimental investigations are presented, focusing on the less well understood high angle boundaries. Measurements of the capacitance of grain boundaries in the overdoped superconductor Y1-xCaxBa2Cu3O7-8, were performed as a function of the calcium content, using the Josephson coupling across the boundaries. Particular care was taken to eliminate the effects of heating and stray capacitance due to the substrate. The effect of thermal noise was also assessed. These measurements provide important information about the area and the width of the grain boundaries, that highlights their inhomogeneous nature. A new technique was applied to measure the normal state properties of YBa2Cu3O7-8 grain boundaries above the critical temperature. Since the resistance of the adjacent material at high temperatures is comparable to, or greater than, that of the grain boundary a compensating Wheatstonebridge structure was used. The errors involved in this technique are carefully assessed and quantified. The normal state resistance of a number of different grain boundary orientations was measured from room temperature to the critical temperature. Detailed characterisation of the grain boundaries, including measurements of the critical current and the current voltage characteristics at low temperatures, was performed. The results obtained are used to assess the validity of the various theories for the grain boundary electrical structure. A tunneling model that accounts for the band structure of the material is developed and applied to potential barriers consistent with a band bending model. This theory is shown to provide a convincing account of the experimental results presented in this thesis.
Download or read book Handbook of II VI Semiconductor Based Sensors and Radiation Detectors written by Ghenadii Korotcenkov and published by Springer Nature. This book was released on 2023-03-30 with total page 700 pages. Available in PDF, EPUB and Kindle. Book excerpt: The reference provides interdisciplinary discussion for diverse II-VI semiconductors with a wide range of topics. The third volume of a three volume set, the book provides an up-to-date account of the present status of multifunctional II-VI semiconductors, from fundamental science and processing to their applications as various sensors, biosensors, and radiation detectors, and based on them to formulate new goals for the further research. The chapters in this volume provide a comprehensive overview of the manufacture, parameters and principles of operation of these devices. The application of these devices in various fields such medicine, agriculture, food quality control, environment monitoring and others is also considered. The analysis carried out shows the great potential of II-VI semiconductor-based sensors and detectors for these applications. Considers solid-state radiation detectors based on semiconductors of II-VI group and their applications; Analyzes the advantages of II-VI compounds to develop chemical and optical gas and ion sensors; Describes all types of biosensors based on II-VI semiconductors and gives examples of their use in various fields.
Download or read book Applications of Chalcogenides S Se and Te written by Gurinder Kaur Ahluwalia and published by Springer. This book was released on 2016-11-02 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces readers to a wide range of applications for elements in Group 16 of the periodic table, such as, optical fibers for communication and sensing, X-ray imaging, electrochemical sensors, data storage devices, biomedical applications, photovoltaics and IR detectors, the rationale for these uses, the future scope of their applications, and expected improvements to existing technologies. Following an introductory section, the book is broadly divided into three parts—dealing with Sulfur, Selenium, and Tellurium. The sections cover the basic structure of the elements and their compounds in bulk and nanostructured forms; properties that make these useful for various applications, followed by applications and commercial products. As the global technology revolution necessitates the search for new materials and more efficient devices in the electronics and semiconductor industry, Applications of Chalcogenides: S, Se, and Te is an ideal book for a wide range of readers in industry, government and academic research facilities looking beyond silicon for materials used in the electronic and optoelectronic industry as well as biomedical applications.
Download or read book Comprehensive Materials Processing written by and published by Newnes. This book was released on 2014-04-07 with total page 5485 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive Materials Processing, Thirteen Volume Set provides students and professionals with a one-stop resource consolidating and enhancing the literature of the materials processing and manufacturing universe. It provides authoritative analysis of all processes, technologies, and techniques for converting industrial materials from a raw state into finished parts or products. Assisting scientists and engineers in the selection, design, and use of materials, whether in the lab or in industry, it matches the adaptive complexity of emergent materials and processing technologies. Extensive traditional article-level academic discussion of core theories and applications is supplemented by applied case studies and advanced multimedia features. Coverage encompasses the general categories of solidification, powder, deposition, and deformation processing, and includes discussion on plant and tool design, analysis and characterization of processing techniques, high-temperatures studies, and the influence of process scale on component characteristics and behavior. Authored and reviewed by world-class academic and industrial specialists in each subject field Practical tools such as integrated case studies, user-defined process schemata, and multimedia modeling and functionality Maximizes research efficiency by collating the most important and established information in one place with integrated applets linking to relevant outside sources
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 1028 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book Grain Boundary Segregation in Metals written by Pavel Lejcek and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Grain boundaries are important structural components of polycrystalline materials used in the vast majority of technical applications. Because grain boundaries form a continuous network throughout such materials, their properties may limit their practical use. One of the serious phenomena which evoke these limitations is the grain boundary segregation of impurities. It results in the loss of grain boundary cohesion and consequently, in brittle fracture of the materials. The current book deals with fundamentals of grain boundary segregation in metallic materials and its relationship to the grain boundary structure, classification and other materials properties.
Download or read book Handbook of Zinc Oxide and Related Materials written by Zhe Chuan Feng and published by CRC Press. This book was released on 2012-09-26 with total page 565 pages. Available in PDF, EPUB and Kindle. Book excerpt: Through their application in energy-efficient and environmentally friendly devices, zinc oxide (ZnO) and related classes of wide gap semiconductors, including GaN and SiC, are revolutionizing numerous areas, from lighting, energy conversion, photovoltaics, and communications to biotechnology, imaging, and medicine. With an emphasis on engineering a
Download or read book Energy Research Abstracts written by and published by . This book was released on 1989 with total page 780 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thermoelectrical Effect in SiC for High Temperature MEMS Sensors written by Toan Dinh and published by Springer. This book was released on 2018-10-05 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the fundamentals of the thermoelectrical effect in silicon carbide (SiC), including the thermoresistive, thermoelectric, thermocapacitive and thermoelectronic effects. It summarizes the growth of SiC, its properties and fabrication processes for SiC devices and introduces the thermoelectrical sensing theories in different SiC morphologies and polytypes. Further, it reviews the recent advances in the characterization of the thermoelectrical effect in SiC at high temperatures. Discussing several desirable features of thermoelectrical SiC sensors and recent developments in these sensors, the book provides useful guidance on developing high sensitivity and linearity, fast-response SiC sensing devices based on thermoelectrical effects.
Download or read book Solar Energy Update written by and published by . This book was released on 1980 with total page 600 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Materials Forum written by and published by . This book was released on 1991 with total page 482 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the National Workshop on Low Cost Polycrystalline Silicon Solar Cells May 18 19 1976 Southern Methodist University Dallas Texas written by Ting L. Chu and published by . This book was released on 1976 with total page 498 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Physics Briefs written by and published by . This book was released on 1992 with total page 1208 pages. Available in PDF, EPUB and Kindle. Book excerpt:
