Download or read book Development of Materials and Structures for P type Contacts in CdTe Solar Cells written by Dino Ferizovic and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The contact performance of Cu2Te thin films was comparable to that of CdTe/ZnTe superlattices and both demonstrated an advantage over contacts based on ZnTe:N thin films which were used a standard.

Download or read book Solar Cells and Modules written by Arvind Shah and published by Springer Nature. This book was released on 2020-07-16 with total page 357 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book gives a comprehensive introduction to the field of photovoltaic (PV) solar cells and modules. In thirteen chapters, it addresses a wide range of topics including the spectrum of light received by PV devices, the basic functioning of a solar cell, and the physical factors limiting the efficiency of solar cells. It places particular emphasis on crystalline silicon solar cells and modules, which constitute today more than 90 % of all modules sold worldwide. Describing in great detail both the manufacturing process and resulting module performance, the book also touches on the newest developments in this sector, such as Tunnel Oxide Passivated Contact (TOPCON) and heterojunction modules, while dedicating a major chapter to general questions of module design and fabrication. Overall, it presents the essential theoretical and practical concepts of PV solar cells and modules in an easy-to-understand manner and discusses current challenges facing the global research and development community.

Download or read book Development of Back Contacts for CdTe Thin Films Solar Cells written by Fadhil Khalaf Dahash Alfadhili and published by . This book was released on 2020 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thin film solar cells based on polycrystalline p-type cadmium telluride (CdTe) represent one of these the most promising photovoltaic (PV) device due to high efficiency and low-cost production. Currently, CdTe solar cells provide the lowest cost electricity generation in utility-scale applications, which is a cost-competitive with the traditional power source, fossil fuel. CdTe thin film PV has attained 22.1 % of power conversion efficiency for small area scale and 18.6 % for modules scale. However, the high efficiency of CdTe devices has been achieved by increasing the photo-generated current by changing the traditional window layer (CdS) of CdTe to a wider bandgap material with better band alignment. The open-circuit voltage (VOC) remains below the theoretical limit due to a barrier at the back of the device due to the deep valence band edge of CdTe (-5.9 eV). Voc can be increased by adding a buffer layer between CdTe and the back electrode to decrease band banding and reducing carrier recombination at the back interface. In this thesis, several materials were investigated as a back-buffer layer, such as single-wall carbon nanotube (SWCNT), zinc telluride (ZnTe), tellurium (Te), and cadmium zinc telluride (CZT) to minimize the bend bending at CdTe/back-buffer layer interface. An alternative method to reduce the carrier recombination at the rear surface, the use of aluminum oxide (Al2O3) layer as a passivation layer was also demonstrated. Finally, an effective method of CdCl2 treatment for CZT thin film was investigated. This method shows that zinc (Zn) can be maintained during the heat treatment.

Download or read book Advances in Composite Materials for Medicine and Nanotechnology written by Brahim Attaf and published by BoD – Books on Demand. This book was released on 2011-04-01 with total page 664 pages. Available in PDF, EPUB and Kindle. Book excerpt: Due to their good mechanical characteristics in terms of stiffness and strength coupled with mass-saving advantage and other attractive physico-chemical properties, composite materials are successfully used in medicine and nanotechnology fields. To this end, the chapters composing the book have been divided into the following sections: medicine, dental and pharmaceutical applications; nanocomposites for energy efficiency; characterization and fabrication, all of which provide an invaluable overview of this fascinating subject area. The book presents, in addition, some studies carried out in orthopedic and stomatological applications and others aiming to design and produce new devices using the latest advances in nanotechnology. This wide variety of theoretical, numerical and experimental results can help specialists involved in these disciplines to enhance competitiveness and innovation.

Download or read book CdTe and Related Compounds Physics Defects Hetero and Nano structures Crystal Growth Surfaces and Applications written by and published by Elsevier. This book was released on 2009-11-11 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Almost thirty years after the remarkable monograph of K. Zanio and the numerous conferences and articles dedicated since that time to CdTe and CdZnTe, after all the significant progresses in that field and the increasing interest in these materials for several extremely attractive industrial applications, such as nuclear detectors and solar cells, the edition of a new enriched and updated monograph dedicated to these two very topical II-VI semiconductor compounds, covering all their most prominent, modern and fundamental aspects, seemed very relevant and useful. - Detailed coverage of the main topics associated with the very topical II-VI semiconductor compound CdTe and its alloy CZT - Review of the CdTe recent developments - Fundamental background of many topics clearly introduced and exposed

Download or read book Applications of Multichannel Spectroscopic Ellipsometry for CdTe Photovoltaics written by Xinxuan Tan and published by . This book was released on 2017 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spectroscopic ellipsometry (SE) is a powerful tool for non-destructive evaluation of thin films consisting of single layers or multilayers on substrates. For such thin films, SE can provide structural parameters and component material optical properties over a wide spectral range. Further analyses of these optical properties can provide additional information of interest on the physical and chemical properties of the materials. Installation of the SE instrument on a deposition chamber enables monitoring of the thin film during deposition. This experiment, referred to as in-situ real time SE (RTSE), enables high surface sensitivity, fast data acquisition, and non-invasive probing which lead to unique insights into the dynamics of film growth. In this dissertation research, RTSE was applied for analysis of the structural evolution of oxygenated CdS (CdS:O) films deposited on c-Si substrates using different [O2 ]/{[Ar] + [O2]} gas flow ratios. The analysis of RTSE data provides valuable information including the initial film growth mode (e.g. layer-by-layer or clustering), subsequent bulk layer and surface roughness thickness evolution, the growth rate in terms of effective thickness (or volume/area), and the final film optical properties. As an additional application of SE, ex situ through-the-glass mapping SE (TG-M-SE) has been used to study the structural properties and area uniformity of CdS/CdTe solar cells over large areas. The mapping results can be correlated with the efficiency of solar cells fabricated over the same area, exploiting inevitable non-uniformities in the process to identify the optimum structural parameters for highest efficiency solar cells. In a second component of this research, RTSE has proven to be very powerful for the development and optimization of thin film FeS2 deposited by a novel hybrid sputtering/co-evaporation method. This effort started with the sputtering of elemental Fe metal thin films and proceeded to the evaporation of sulfur simultaneously with Fe deposition using different overall rates and substrate temperatures. The effects of these deposition parameters on the resulting iron sulfide film properties were explored. The nucleation, growth evolution, and optical properties of thin film FeS2 deposited by this hybrid method are key outcomes of this study that relies on in-situ RTSE. Other characterization techniques including X-ray diffractometry, scanning electron microscopy SEM, and energy-dispersive X-ray spectroscopy (EDS) were used in the dissertation research to determine the crystal structure, surface microstructure, and the S:Fe atomic ratio of the iron sulfide films to complement the RTSE analysis. In the final component of this dissertation research, CdTe/CdS solar cells in the substrate configuration were fabricated and studied. Development of CdTe/CdS solar cells in this non-standard configuration provides an alternative approach for exploring CdTe back contacts that may require high-temperature vacuum processing. The experimental research on this subject started with a study of the effect of CdS bath temperature on the CdS/CdTe solar cell performance in the superstrate configuration in an attempt to advance the process for use in the substrate configuration. Materials including MoO3, copper indium selenide (CIS), and nitrogen doped CIS (CIS:N) were studied as p-type back contact interlayers between Mo and CdTe in the CdTe/CdS substrate configuration solar cells. The performance of the solar cells incorporating these p-type back contacts are compared and discussed in the dissertation.

Download or read book Solar Cell Technology and Applications written by A. R. Jha and published by CRC Press. This book was released on 2009-10-14 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: Energy experts predict that wholesale electricity prices could easily rise 35 to 65 percent by 2015. Add to this the growing need for energy independence and the need to reduce carbon emissions and it is very clear that the development of low-cost renewable energy, such as solar energy, is essential for our economy and our national security. With t

Download or read book Energy Conversion written by D. Yogi Goswami and published by CRC Press. This book was released on 2017-07-06 with total page 1193 pages. Available in PDF, EPUB and Kindle. Book excerpt: This handbook surveys the range of methods and fuel types used in generating energy for industry, transportation, and heating and cooling of buildings. Solar, wind, biomass, nuclear, geothermal, ocean and fossil fuels are discussed and compared, and the thermodynamics of energy conversion is explained. Appendices are provided with fully updated data. Thoroughly revised, this second edition surveys the latest advances in energy conversion from a wide variety of currently available energy sources. It describes energy sources such as fossil fuels, biomass (including refuse-derived biomass fuels), nuclear, solar radiation, wind, geothermal, and ocean, then provides the terminology and units used for each energy resource and their equivalence. It includes an overview of the steam power cycles, gas turbines, internal combustion engines, hydraulic turbines, Stirling engines, advanced fossil fuel power systems, and combined-cycle power plants. It outlines the development, current use, and future of nuclear power.

Download or read book Proceedings of the 1986 International Congress on Renewable Energy Sources written by S. Terol and published by Editorial CSIC - CSIC Press. This book was released on with total page 1942 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Coatings and Thin Film Technologies written by Jaime Andres Perez Taborda and published by BoD – Books on Demand. This book was released on 2019-01-03 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: The field of coatings and thin-film technologies is rapidly advancing to keep up with new uses for semiconductor, optical, tribological, thermoelectric, solar, security, and smart sensing applications, among others. In this sense, thin-film coatings and structures are increasingly sophisticated with more specific properties, new geometries, large areas, the use of heterogeneous materials and flexible and rigid coating substrates to produce thin-film structures with improved performance and properties in response to new challenges that the industry presents. This book aims to provide the reader with a complete overview of the current state of applications and developments in thin-film technology, discussing applications, health and safety in thin films, and presenting reviews and experimental results of recognized experts in the area of coatings and thin-film technologies.

Download or read book Handbook of Chalcogen Chemistry written by Francesco Devillanova and published by Royal Society of Chemistry. This book was released on 2013-07-25 with total page 499 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Handbook of Chalcogen Chemistry: New Perspectives in Sulfur, Selenium and Tellurium provides an overview of recent developments, particularly from the last decade, on the chemistry of the chalcogen group elements (S, Se and Te). While up to a few decades ago, chalcogen chemistry was mainly centred on sulphur, in recent years the research based on Se and Te has increased dramatically, and has created huge scope for the use of compounds based on this type of chemistry. The Handbook is organised into two parts, the first of which deals systematically with the chemistry of chalcogens in relation to other group elements in the periodic table. It also includes an overview of metal-chalcogenides and metal-polychalcogenides. The second part reflects the interdisciplinary nature of chalcogen chemistry and focuses on biological, materials and supramolecular aspects of the field. This Handbook gives a comprehensive overview on recent developments over the last decade and is ideal for researchers in the field.

Download or read book Development and Application of Transparent P type Back Contact Layers for Bifacial CdTe Solar Cells written by Kamala Khanal Subedi and published by . This book was released on 2021 with total page 0 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 1981-04 with total page 680 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Multichannel Spectroscopic Ellipsometry for CdTe Photovoltaics written by Prakash Koirala and published by . This book was released on 2015 with total page 363 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spectroscopic ellipsometry (SE) in the mid-infrared to ultraviolet range has been implemented in order to develop and evaluate optimization procedures for CdTe solar cells at the different stages of fabrication. In this dissertation research, real time SE (RT-SE) has been applied during the fabrication of the as-deposited CdS/CdTe solar cell. Two areas of background research were addressed before undertaking the challenging RT-SE analysis procedures. First, optical functions were parameterized versus temperature for the glass substrate and its overlayers, including three different SnO2 layers. This database has applications not only for RT-SE analysis but also for on-line monitoring of the coated glass itself at elevated temperature. Second, post-deposition modifications of substrate have been studied by infrared spectroscopic ellipsometry (IR-SE) prior to the RT-SE analysis in order to evaluate the need for such modification in the analysis. With support from these background studies, RT-SE has been implemented in analyses of the evolution of the thin film structural properties during sputter deposition of polycrystalline CdS/CdTe solar cells on the transparent conducting oxide (TCO) coated glass substrates. The real time optical spectra collected during CdS/CdTe deposition were analyzed using the optical property database for all substrate components as a function of measurement temperature. RT-SE enables characterization of the filling process of the surface roughness modulations on the top-most SnO2 substrate layer, commonly referred to as the high resistivity transparent (HRT) layer. In this filling process, the optical properties of this surface layer are modified in accordance with an effective medium theory. In addition to providing information on interface formation to the substrate during film growth, RT-SE also provides information on the bulk layer CdS growth, its surface roughness evolution, as well as overlying CdTe interface formation and bulk layer growth. Information from RT-SE at a single point during solar cell stack deposition assists in the development of a model that has been used for mapping the properties of the completed cell stack, which can then be correlated with device performance. Independent non-uniformities in the layers over the full area of the cell stack enable optimization of cell performance combinatorially.The polycrystalline CdS/CdTe thin-film solar cell in the superstrate configuration has been studied by SE using glass side illumination whereby the single reflection from the glass/film-stack interface is collected whereas that from the ambient/glass interface and those from multiple glass/film-stack reflections are rejected. The SE data analysis applies an optical model consisting of a multilayer stack with bulk and interface layers. The dielectric functions ¿¿for the solar cell component materials were obtained by variable-angle and in-situ SE. Variability in the properties of the materials are introduced through free parameters in analytical expressions for the dielectric functions. In the SE analysis of the complete cell, a step-wise procedure ranks all free parameters of the model, including thicknesses and those defining the spectra in¿¿, according to their ability to reduce the root-mean-square deviation between simulated and measured SE spectra. The results for the best fit thicknesses compare well with electron microscopy. From the optical model, including all best-fit parameters, the solar cell quantum efficiency (QE) can be simulated without free parameters, and comparisons with QE measurements have enabled the identification of losses. The capabilities have wide applications in off-line photovoltaic module mapping and in-line monitoring of coated glass at intermediate stages of production. Mapping spectroscopic ellipsometry (M-SE) has been applied in this dissertation research as an optimization procedure for polycrystalline CdS/CdTe solar cell fabrication on TCO coated glass superstrates. During fabrication of these solar cells, the structure undergoes key processing steps after the sputter-deposition of the CdS/CdTe. These steps include CdCl2 treatment of the CdTe layer and subsequent deposition of ultrathin Cu. Additional steps involve final metal back contact layer deposition and an anneal for Cu diffusion that completes the device. In this study, we have fabricated cells with variable absorber thicknesses, ranging from 0.5 to 2.5 ¿m, and variable CdCl2 treatment times, ranging from 5 to 30 min. Because both CdS window and Cu back contact layers are critical for determining device performance, the ability to characterize their deposition processes and determine the resulting process-property-performance relationships is important for device optimization. We have applied M-SE to map the effective thickness (volume/area) of the CdS and Cu films over 15 cm x 15 cm substrates prior to the fabrication of 16 x 16 arrays of dot cells. We report correlations of cell performance parameters with the CdCl2 treatment time and with the effective thicknesses from M-SE analysis. We demonstrate that correlations between optical/structural parameters extracted from M-SE analysis and device performance parameters facilitate process optimization. We have explored and applied p-type semiconducting materials as novel back contact materials in CdTe solar cells. Wide band-gap, p-type doped, hydrogenated amorphous silicon-carbon alloy (a-Si1-xCx:H:B) layers deposited by plasma enhanced chemical vapor deposition (PECVD) under conditions that yield efficient hydrogenated amorphous silicon (a Si:H) p-i-n solar cells have been applied as back contacts to sputter-deposited CdTe superstrate solar cells. We report a maximum observed Voc value of 0.78 V and a best initial efficiency of ~ 7.7 % (relative to an ~ 12% standard cell baseline) without the introduction of Cu into the back contact region. Instability of solar cells that incorporate such back contacts have hindered their further development. We also applied copper indium diselenide (CuInSe2) as a novel back contact material in CdTe solar cells in the superstrate configuration. We report a maximum observed Voc value of 0.68 V and a best efficiency of ~ 6.4 % (relative to an ~ 12.6 % standard cell baseline) without the introduction of Cu.

Download or read book Sixteenth European Photovoltaic Solar Energy Conference written by H. Scheer and published by Routledge. This book was released on 2020-11-25 with total page 3235 pages. Available in PDF, EPUB and Kindle. Book excerpt: The European Photovoltaic Solar Energy Conferences are dedicated to accelerating the impetus towards sustainable development of global PV markets. The 16th in the series, held in Glasgow UK, brought together more than 1500 delegates from 72 countries, and provided an important and vital forum for information exchange in the field. The Conference Proceedings place on record a new phase of market development and scientific endeavour in the PV industry, representing current and innovative thinking in all aspects of the science, technology, markets and business of photovoltaics. In three volumes, the Proceedings present some 790 papers selected for presentation by the scientific review committee of the 16th European Photovoltaic Solar Energy Conference. The comprehensive range of topics covered comprise: * Fundamentals, Novel Devices and New Materials * Thin Film Cells and Technologies * Space Cells and Systems * Crystalline Silicon Solar Cells and Technologies * PV Integration in Buildings * PV Modules and Components of PV Systems * Implementation, Strategies, National Programs and Financing Schemes * Market Deployment in Developing Countries These proceedings are an essential reference for all involved in the global PV industry- scientists, researchers, technologists and those with an interest in global market trends. The conference was organised by WIP-Renewable Energies, Munich, Germany.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Semiconductor Photovoltaic Cells written by Chunfu Zhang and published by Springer Nature. This book was released on 2021-02-25 with total page 470 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book explores the scientific basis of the photovoltaic effect, solar cell operation, various types of solar cells, and the main process used in their manufacture. It addresses a range of topics, including the production of solar silicon; silicon-based solar cells and modules; the choice of semiconductor materials and their production-relevant costs and performance; device structures, processing, and manufacturing options for the three major thin-film PV technologies; high-performance approaches for multi-junction, concentrator, and space applications; and new types of organic polymer and dye-sensitized solar cells. The book also presents a concept for overcoming the efficiency limit of today’s solar cells. Accessible for beginners, while also providing detailed information on the physics and technology for experts, the book is a valuable resource for researchers, engineers, and graduate students in fields such as physics, materials, energy, electrical and electronic engineering and microelectronics.