Download or read book In Situ Optical Imaging of Carrier Transport in Multilayer Solar Cells written by and published by . This book was released on 2008 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of this thesis is to explore the utility of in-situ optical imaging of charge transport imaging in multi junction solar cells. An in-situ measurement of a manufactured solar cell's key material parameters is difficult. Many sophisticated models may be used to predict performance of new cell arrangements and suggest next generation improvements. In parallel, an experimental view into a complex, multi layered, alloyed semiconductor device can provide important feedback for material growth and device fabrication. This body of work builds on the previous work of extracting estimated minority carrier diffusion lengths from multi junction solar cell materials. Indium Gallium Phosphide double heterostructures have been investigated previously with effective results. A technique to estimate electron diffusion length from a luminescent sample intensity distribution has been developed. This thesis investigates imaging transport and applying the diffusion length estimation directly in the triple junction device. Luminescence from individual layers was isolated using optical filters. The effect of varying temperature and applying bias during the imaging technique is investigated as well. A strong dependence of effective diffusion length on environmental temperature was measured. In addition, a weak dependence of effective diffusion length on bias was measured, with the effect slightly greater in the top, as compared to the central cell.
Download or read book Direct Imaging of Minority Charge Carrier Transport in Triple Junction Solar Cell Layers written by Ted Jonathan Mills and published by . This book was released on 2006 with total page 81 pages. Available in PDF, EPUB and Kindle. Book excerpt: An optical, contact-free method for measuring minority carrier diffusion lengths is developed and demonstrated for a range of semiconductor materials used in high efficiency triple junction solar cells. This method uses a Scanning Electron Microscope (SEM) coupled with an optical microscope. The diffusion lengths, combined with minority carrier lifetime measured via time-resolved photoluminescence, allow for the computation of minority charge carrier mobility. The technique uses images to extract diffusion length measurements from GaAs, InGaAs, and InGaP heterostructures at different SEM beam energies and probe currents. Excellent correlation between measurements shows the reproducibility of this technique. Diffusion lengths from 2-63 microns have been measured in a variety of GaAs, InGaAs, and InGaP samples. Effects of alloy ordering, doping, and lattice matching have been investigated. Several areas for further research are offered, including detailed radiation-damage mapping of solar cell layers. Further anisotropic studies of the solar cell layers are suggested to investigate the directional dependence of diffusion length within the InGaP heterostructures. Finally, new and emerging solar cell materials would benefit from this technique, allowing for the complete characterization of minority charge transport properties before growing an entire solar cell.
Download or read book Quantitative Carrier Transport in Quantum Dot Photovoltaic Solar Cells from Novel Photocarrier Radiometry and Lock in Carrierography written by Lilei Hu and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Colloidal quantum dots (CQDs) are promising candidates for fabricating large-scale, low-cost, flexible, and lightweight photovoltaic solar cells. However, their power conversion efficiency is still insufficient for commercial applications, partly and significantly, due to the not-well-understood carrier transport mechanisms and the lack of effective characterization techniques. Addressing these issues, carrier transport kinetics in CQD systems were studied to develop high-frequency dynamic testing and/or large-area quantitative imaging techniques: photocarrier radiometry (PCR), and homodyne (HoLIC) and heterodyne (HeLIC) lock-in carrierographies. Based on the discrete carrier hopping transport in CQDs, various carrier drift-diffusion current-voltage (J-V) analytical models and new concepts including the imbalanced carrier mobilities, reversed Schottky barrier, and double-diode model were developed to quantitatively interpret carrier transport and J-V characteristics in CQD solar cells. The further quantitative study of carrier mobility, CQD bandgap energy, phonon-assisted carrier transport, and open-circuit voltage deficit revealed CQD solar cell efficiency optimization strategies. Applying these energy transport mechanisms, for the first time, an analytical PCR signal generation model for CQD systems was developed from a novel trap-state-mediated carrier hopping transport theory. Therefore, multiple carrier transport parameters including carrier hopping lifetime, diffusivity, and diffusion length were extracted to investigate carrier transport dependencies on temperature, quantum dot size, surface-passivation ligands, and carrier hopping activation energies. As an imaging extension of PCR, using a heterodyne method to overcome the limitations of camera frame rate and exposure time of even the state-of-the-art InGaAs cameras, the first camera-based HeLIC theoretical model for ultrahigh-frequency (up to 270 kHz) imaging of CQD solar cells was achieved. Therefore, quantitative imaging of carrier lifetime, diffusivity, and diffusion and drift lengths of CQD solar cells was accomplished to explore the influences of carrier transport and contact/CQD interface on CQD solar cells. Also, low-frequency HoLIC large-area imaging evaluated the sample homogeneity and quality, reflecting preliminary carrier lifetime distribution. The combination of the novel carrier discrete hopping transport mechanism, J-V models, PCR, and the lock-in carrierography techniques (HoLIC and HeLIC) shows great potential for quantitative carrier transport study of CQD solar cells and for fast, all-optical, contactless, large-area, and nondestructive characterization of commercial photovoltaic materials and devices.
Download or read book Spectroscopic Ellipsometry for Photovoltaics written by Hiroyuki Fujiwara and published by Springer. This book was released on 2019-01-10 with total page 628 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spectroscopic ellipsometry has been applied to a wide variety of material and device characterizations in solar cell research fields. In particular, device performance analyses using exact optical constants of component layers and direct analyses of complex solar cell structures are unique features of advanced ellipsometry methods. This second volume of Spectroscopic Ellipsometry for Photovoltaics presents various applications of the ellipsometry technique for device analyses, including optical/recombination loss analyses, real-time control and on-line monitoring of solar cell structures, and large-area structural mapping. Furthermore, this book describes the optical constants of 148 solar cell component layers, covering a broad range of materials from semiconductor light absorbers (inorganic, organic and hybrid perovskite semiconductors) to transparent conductive oxides and metals. The tabulated and completely parameterized optical constants described in this book are the most current resource that is vital for device simulations and solar cell structural analyses.
Download or read book Chemical Abstracts written by and published by . This book was released on 2002 with total page 2676 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 1995 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Materials Concepts For Solar Cells Second Edition written by Thomas Dittrich and published by World Scientific Publishing Company. This book was released on 2018-01-30 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt: A modern challenge is for solar cell materials to enable the highest solar energy conversion efficiencies, at costs as low as possible, and at an energy balance as sustainable as necessary in the future. This textbook explains the principles, concepts and materials used in solar cells. It combines basic knowledge about solar cells and the demanded criteria for the materials with a comprehensive introduction into each of the four classes of materials for solar cells, i.e. solar cells based on crystalline silicon, epitaxial layer systems of III-V semiconductors, thin-film absorbers on foreign substrates, and nano-composite absorbers. In this sense, it bridges a gap between basic literature on the physics of solar cells and books specialized on certain types of solar cells.The last five years had several breakthroughs in photovoltaics and in the research on solar cells and solar cell materials. We consider them in this second edition. For example, the high potential of crystalline silicon with charge-selective hetero-junctions and alkaline treatments of thin-film absorbers, based on chalcopyrite, enabled new records. Research activities were boosted by the class of hybrid organic-inorganic metal halide perovskites, a promising newcomer in the field.This is essential reading for students interested in solar cells and materials for solar cells. It encourages students to solve tasks at the end of each chapter. It has been well applied for postgraduate students with background in materials science, engineering, chemistry or physics.
Download or read book Perovskite Photovoltaics written by Aparna Thankappan and published by Academic Press. This book was released on 2018-06-29 with total page 521 pages. Available in PDF, EPUB and Kindle. Book excerpt: Perovskite Photovoltaics: Basic to Advanced Concepts and Implementation examines the emergence of perovskite photovoltaics, associated challenges and opportunities, and how to achieve broader development. Consolidating developments in perovskite photovoltaics, including recent progress solar cells, this text also highlights advances and the research necessary for sustaining energy. Addressing different photovoltaics fields with tailored content for what makes perovskite solar cells suitable, and including commercialization examples of large-scale perovskite solar technology. The book also contains a detailed analysis of the implementation and economic viability of perovskite solar cells, highlighting what photovoltaic devices need to be generated by low cost, non-toxic, earth abundant materials using environmentally scalable processes. This book is a valuable resource engineers, scientists and researchers, and all those who wish to broaden their knowledge on flexible perovskite solar cells. - Includes contributions by leading solar cell academics, industrialists, researchers and institutions across the globe - Addresses different photovoltaics fields with tailored content for what makes perovskite solar cells different - Provides commercialization examples of large-scale perovskite solar technology, giving users detailed analysis on the implementation, technical challenges and economic viability of perovskite solar cells
Download or read book Science Abstracts written by and published by . This book was released on 1995 with total page 1360 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Printable Solar Cells written by Nurdan Demirci Sankir and published by John Wiley & Sons. This book was released on 2017-04-19 with total page 578 pages. Available in PDF, EPUB and Kindle. Book excerpt: Printable Solar Cells The book brings together the recent advances, new and cutting edge materials from solution process and manufacturing techniques that are the key to making photovoltaic devices more efficient and inexpensive. Printable Solar Cells provides an overall view of the new and highly promising materials and thin film deposition techniques for printable solar cell applications. The book is organized in four parts. Organic and inorganic hybrid materials and solar cell manufacturing techniques are covered in Part I. Part II is devoted to organic materials and processing technologies like spray coating. This part also demonstrates the key features of the interface engineering for the printable organic solar cells. The main focus of Part III is the perovskite solar cells, which is a new and promising family of the photovoltaic applications. Finally, inorganic materials and solution based thin film formation methods using these materials for printable solar cell application is discussed in Part IV. Audience The book will be of interest to a multidisciplinary group of fields, in industry and academia, including physics, chemistry, materials science, biochemical engineering, optoelectronic information, photovoltaic and renewable energy engineering, electrical engineering, mechanical and manufacturing engineering.
Download or read book High Efficiency Silicon Solar Cells written by Martin A. Green and published by Trans Tech Publications Ltd. This book was released on 1987-01-01 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: The early chapters comprehensively review the optical and transport properties of silicon. Light trapping is described in detail. Limits on the efficiency of silicon cells are discussed as well as material requirements necessary to approach these limits. The status of current approaches to passifying surfaces, contacts and bulk regions is reviewed. The final section of the book describes the most practical approaches to the fabrication of high-efficiency cells capable of meeting the efficiency targets for both concentrated and non-concentrated sunlight, including a discussion of design and processing approaches for non-crystalline silicon.
Download or read book Physics Briefs written by and published by . This book was released on 1994 with total page 1170 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Multilayer Thin Films written by Sukumar Basu and published by BoD – Books on Demand. This book was released on 2020-01-15 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book, "Multilayer Thin Films-Versatile Applications for Materials Engineering", includes thirteen chapters related to the preparations, characterizations, and applications in the modern research of materials engineering. The evaluation of nanomaterials in the form of different shapes, sizes, and volumes needed for utilization in different kinds of gadgets and devices. Since the recently developed two-dimensional carbon materials are proving to be immensely important for new configurations in the miniature scale in the modern technology, it is imperative to innovate various atomic and molecular arrangements for the modifications of structural properties. Of late, graphene and graphene-related derivatives have been proven as the most versatile two-dimensional nanomaterials with superb mechanical, electrical, electronic, optical, and magnetic properties. To understand the in-depth technology, an effort has been made to explain the basics of nano dimensional materials. The importance of nano particles in various aspects of nano technology is clearly indicated. There is more than one chapter describing the use of nanomaterials as sensors. In this volume, an effort has been made to clarify the use of such materials from non-conductor to highly conducting species. It is expected that this book will be useful to the postgraduate and research students as this is a multidisciplinary subject.
Download or read book Electronic Processes in Organic Semiconductors written by Anna Köhler and published by John Wiley & Sons. This book was released on 2015-06-08 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first advanced textbook to provide a useful introduction in a brief, coherent and comprehensive way, with a focus on the fundamentals. After having read this book, students will be prepared to understand any of the many multi-authored books available in this field that discuss a particular aspect in more detail, and should also benefit from any of the textbooks in photochemistry or spectroscopy that concentrate on a particular mechanism. Based on a successful and well-proven lecture course given by one of the authors for many years, the book is clearly structured into four sections: electronic structure of organic semiconductors, charged and excited states in organic semiconductors, electronic and optical properties of organic semiconductors, and fundamentals of organic semiconductor devices.
Download or read book Photovoltaic and Photoactive Materials written by Joseph M. Marshall and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 361 pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary objective of this NATO Advanced Study Institute (ASI) was to present an up-to-date overview of various current areas of interest in the field of photovoltaic and related photoactive materials. This is a wide-ranging subject area, of significant commercial and environmental interest, and involves major contributions from the disciplines of physics, chemistry, materials, electrical and instrumentation engineering, commercial realisation etc. Therefore, we sought to adopt an inter disciplinary approach, bringing together recognised experts in the various fields while retaining a level of treatment accessible to those active in specific individual areas of research and development. The lecture programme commenced with overviews of the present relevance and historical development of the subject area, plus an introduction to various underlying physical principles of importance to the materials and devices to be addressed in later lectures. Building upon this, the ASI then progressed to more detailed aspects of the subject area. We were also fortunately able to obtain a contribution from Thierry Langlois d'Estaintot of the European Commission Directorate, describing present and future EC support for activities in this field. In addition, poster sessions were held throughout the meeting, to allow participants to present and discuss their current activities. These were supported by what proved to be very effective feedback sessions (special thanks to Martin Stutzmann), prior to which groups of participants enthusiastically met (often in the bar) to identify and agree topics of common interest.
Download or read book Perovskite Solar Cells written by Shahzada Ahmad and published by John Wiley & Sons. This book was released on 2022-03-14 with total page 580 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents a thorough overview of perovskite research, written by leaders in the field of photovoltaics The use of perovskite-structured materials to produce high-efficiency solar cells is a subject of growing interest for academic researchers and industry professionals alike. Due to their excellent light absorption, longevity, and charge-carrier properties, perovskite solar cells show great promise as a low-cost, industry-scalable alternative to conventional photovoltaic cells. Perovskite Solar Cells: Materials, Processes, and Devices provides an up-to-date overview of the current state of perovskite solar cell research. Addressing the key areas in the rapidly growing field, this comprehensive volume covers novel materials, advanced theory, modelling and simulation, device physics, new processes, and the critical issue of solar cell stability. Contributions by an international panel of researchers highlight both the opportunities and challenges related to perovskite solar cells while offering detailed insights on topics such as the photon recycling processes, interfacial properties, and charge transfer principles of perovskite-based devices. Examines new compositions, hole and electron transport materials, lead-free materials, and 2D and 3D materials Covers interface modelling techniques, methods for modelling in two and three dimensions, and developments beyond Shockley-Queisser Theory Discusses new fabrication processes such as slot-die coating, roll processing, and vacuum sublimation Describes the device physics of perovskite solar cells, including recombination kinetics and optical absorption Explores innovative approaches to increase the light conversion efficiency of photovoltaic cells Perovskite Solar Cells: Materials, Processes, and Devices is essential reading for all those in the photovoltaic community, including materials scientists, surface physicists, surface chemists, solid state physicists, solid state chemists, and electrical engineers.
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1999 with total page 1042 pages. Available in PDF, EPUB and Kindle. Book excerpt:
