Download or read book Thin film Cadmium Telluride and Zinc Phosphide Solar Cells written by Ting L. Chu and published by . This book was released on 1984 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report on thin-film cadmium telluride and zinc phosphide solar cells describes work on the deposition of CdTe films by direct combination of Cd and Te vapor on foreign substrates, with emphasis on the resistivity control of p-type films and on the reduction of p-CdTe/substrate interface resistance. CdTe films deposited on graphite substrates were all p-type, regardless of substrate temperature or reactant composition. Deposition and characterization of window materials also continued. Thin-film CdTe heterojunction solar cells were also prepared and characterized. The best CdS/CdTe cells in this work have had an AM1 efficiency of about 6.5% and the best ITO/CdTe cell to date has had an AM1 efficiency of about 8%.
Download or read book Thin film Cadmium Telluride and Zinc Phosphide Solar Cells written by Ting L. Chu and published by . This book was released on 1984 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report on thin-film cadmium telluride and zinc phosphide solar cells describes work on the deposition of CdTe films by direct combination of Cd and Te vapor on foreign substrates, with emphasis on the resistivity control of p-type films and on the reduction of p-CdTe/substrate interface resistance. CdTe films deposited on graphite substrates were all p-type, regardless of substrate temperature or reactant composition. Deposition and characterization of window materials also continued. Thin-film CdTe heterojunction solar cells were also prepared and characterized. The best CdS/CdTe cells in this work have had an AM1 efficiency of about 6.5% and the best ITO/CdTe cell to date has had an AM1 efficiency of about 8%.
Download or read book Copper Zinc Tin Sulfide Based Thin Film Solar Cells written by Kentaro Ito and published by John Wiley & Sons. This book was released on 2015-02-23 with total page 449 pages. Available in PDF, EPUB and Kindle. Book excerpt: Beginning with an overview and historical background of Copper Zinc Tin Sulphide (CZTS) technology, subsequent chapters cover properties of CZTS thin films, different preparation methods of CZTS thin films, a comparative study of CZTS and CIGS solar cell, computational approach, and future applications of CZTS thin film solar modules to both ground-mount and rooftop installation. The semiconducting compound (CZTS) is made up earth-abundant, low-cost and non-toxic elements, which make it an ideal candidate to replace Cu(In,Ga)Se2 (CIGS) and CdTe solar cells which face material scarcity and toxicity issues. The device performance of CZTS-based thin film solar cells has been steadily improving over the past 20 years, and they have now reached near commercial efficiency levels (10%). These achievements prove that CZTS-based solar cells have the potential to be used for large-scale deployment of photovoltaics. With contributions from leading researchers from academia and industry, many of these authors have contributed to the improvement of its efficiency, and have rich experience in preparing a variety of semiconducting thin films for solar cells.
Download or read book Thin Film Cadmium Telluride Zinc Telluride and Mercury Zinc Telluride Solar Cells written by and published by . This book was released on 1992 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes research to demonstrate (1) thin film cadmium telluride solar cells with a quantum efficiency of 75% or higher at 0. 44?m and a photovoltaic efficiency of 11.5% or greater, and (2) thin film zinc telluride and mercury zinc telluride solar cells with a transparency to sub-band-gap radiation of 65% and a photovoltaic conversion efficiency of 5% and 8%, respectively. Work was directed at (1) depositing transparent conducting semiconductor films by solution growth and metal-organic chemical vapor deposition (MOCVD) technique, (2) depositing CdTe films by close-spaced sublimation (CSS) and MOCVD techniques, (3) preparing and evaluating thin film CdTe solar cells, and (4) preparing and characterizing thin film ZnTe, CD{sub 1-x}Zn{sub 1-x}Te, and Hg{sub 1-x}ZnxTe solar cells. The deposition of CdS films from aqueous solutions was investigated in detail, and their crystallographic, optical, and electrical properties were characterized. CdTe films were deposited from DMCd and DIPTe at 400°C using TEGa and AsH3 as dopants. CdTe films deposited by CSS had significantly better microstructures than those deposited by MOCVD. Deep energy states in CdTe films deposited by CSS and MOCVD were investigated. Thin films of ZnTe, Cd{sub 1- x}ZnxTe, and Hg{sub 1-x}ZnxTe were deposited by MOCVD, and their crystallographic, optical, and electrical properties were characterized. 67 refs.
Download or read book High Efficiency Cadmium and Zinc Telluride based Thin Film Solar Cells written by and published by . This book was released on 1990 with total page 83 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polycrystalline Cd{sub 1-x}Zn(subscript x)Te and Cd{sub 1-x}Mn(subscript x)Te films with a band gap of 1.7 eV were successfully grown on glass/SnO2/CdS substrates by molecular beam epitaxy (MBE) and metal-organic chemical vapor deposition (MOCVD), respectively. Polycrystalline Cd{sub 1-x}Zn(subscript x)Te films grown by MBE resulted in uniform composition and sharp interfaces. However, polycrystalline Cd{sub 1-x}Mn(subscript x)Te films grown by MOCVD showed nonuniform compositions and evidence of manganese accumulation at the Cd{sub 1-x}Mn(subscript x)Te/CdS interface. We found that manganese interdiffuses and replaces cadmium in the CdS film. By improving the CdTe/CdS interface and, thus, reducing the collection function effects, the efficiency of the MOCVD CdTe cell can be improved to about 13.5%. MBE-grown CdTe cells also produced 8%--9% efficiencies. The standard CdTe process was not optimum for ternary films and resulted in a decrease in the band gap. Recent results indicate that CdCl2 + ZnCl2 chemical treatment may prevent the band-gap reduction, and that chromate etch (rather than bromine etch) may provide the solution to contact resistance in the ternary cells.
Download or read book High Efficiency Cadmium Telluride and Zinc Telluride Based Thin film Solar Cells written by and published by . This book was released on 1992 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes work to improve the basic understanding of CdTe and ZnTe alloys by growing and characterizing these films along with cell fabrication. The major objective was to develop wide-band-gap (1.6--1.8 eV) material for the top cell, along with compatible window material and transparent ohmic contacts, so that a cascade cell design can be optimized. Front-wall solar cells were fabricated with a glass/SnO2/CdS window, where the CdS film is thin to maximize transmission and current. Wide-band-gap absorber films (E{sub g} = 1.75 eV) were grown by molecular beam epitaxy (MBE) and metal-organic chemical vapor deposition (MOCVD) techniques, which provided excellent control for tailoring the film composition and properties. CdZnTe films were grown by both MBE and MOCVD. All the as-grown films were characterized by several techniques (surface photovoltage spectroscopy, Auger electron spectroscopy (AES), and x-ray photoelectron spectroscopy (XPS)) for composition, bulk uniformity, thickness, and film and interface quality. Front-wall-type solar cells were fabricated in collaboration with Ametek Materials Research Laboratory using CdTe and CdZnTe polycrystalline absorber films. The effects of processing on ternary film were studied by AES and XPS coupled with capacitance voltage and current voltage measurements as a function of temperature. Bias-dependent spectral response and electrical measurements were used to test some models in order to identify and quantify dominant loss mechanisms.
Download or read book Thin Film Cadmium Telluride Zinc Telluride and Mercury Zinc Telluride Solar Cells written by Ting L. Chu and published by . This book was released on 1989 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thin Films and Solar Cells of Cadmium Telluride and Cadmium Zinc Telluride written by Christos Savva Ferekides and published by . This book was released on 1991 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High Efficiency Cadmium and Zinc Telluride Based Thin Film Solar Cells written by A. Rohatgi and published by . This book was released on 1987 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book SERI Photovoltaic Advanced Research and Development Bibliography 1982 1985 written by and published by . This book was released on 1986 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High efficiency Cadmium and Zinc Telluride Based Thin film Solar Cells written by and published by . This book was released on 1989 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Properties of Thin Film Cadmium Sulfide Used in Cadmium Telluride cadmium Sulfide Solar Cell written by Xiawa Wu and published by ProQuest. This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: CdTe/CdS solar cell is one of the promising low cost high efficiency thin film solar cells. In this work, thin film CdS properties and the effect of CdS surface conditions on CdTe growth and performance of polycrystalline CdTe/CdS thin film solar cells are investigated. Thin film CdS optical, structural and chemical properties both as deposited and after CdCl 2 heat treatment are measured. CdS surface chemical state is studied by analyzing its surface chemistry after different surface treatments. Qualitative and quantitative measurements indicate sulfate and sulfite phases on thin film CdS surfaces as well as single crystal CdS, caused by oxidation in the air. The degree of CdS oxidation is highly dependent on thermal treatment ambient, temperature and time. Results indicate reduction in grain size and smoother morphology for CdTe deposited on heavily oxidized CdS compared to chemically reduced CdS surface. Solar cell open circuit voltage is much lower on cells with heavily oxidized CdS surface.
Download or read book Thin Film Solar Cells written by K. L. Chopra and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 615 pages. Available in PDF, EPUB and Kindle. Book excerpt: "You, 0 Sun, are the eye of the world You are the soul of all embodied beings You are the source of all creatures You are the discipline of all engaged in work" - Translated from Mahabharata 3rd Century BC Today, energy is the lifeline and status symbol of "civilized" societies. All nations have therefore embarked upon Research and Development pro grams of varying magnitudes to explore and effectively utilize renewable sources of energy. Albeit a low-grade energy with large temporal and spatial variations, solar energy is abundant, cheap, clean, and renewable, and thus presents a very attractive alternative source. The direct conver sion of solar energy to electricity (photovoltaic effect) via devices called solar cells has already become an established frontier area of science and technology. Born out of necessity for remote area applications, the first commercially manufactured solar cells - single-crystal silicon and thin film CdS/Cu2S - were available well over 20 years ago. Indeed, all space vehicles today are powered by silicon solar cells. But large-scale terrestrial applications of solar cells still await major breakthroughs in terms of discovering new and radical concepts in solar cell device structures, utilizing relatively more abundant, cheap, and even exotic materials, and inventing simpler and less energy intensive fabrication processes. No doubt, this extraordinary challenge in R/D has led to a virtual explosion of activities in the field of photovoltaics in the last several years.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1993 with total page 754 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High Efficiency Ultra Thin Cadmium Telluride CdTe Solar Cells written by Nowshad Amin and published by LAP Lambert Academic Publishing. This book was released on 2013 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thin film cadmium telluride absorbers with cadmium sulphide hetero-junction partner are promising candidates for high efficiency low cost solutions of solar energy harvesting devices. These devices have band gaps well-suited for effective absorption of sunlight. Most importantly, the materials used in these devices can be deposited in a variety of industry-friendly ways, so that the cost associated with manufacturing is generally lower than other available technologies. Although poly-crystalline CdS has been found to be the best suited heterojunction partner for CdTe solar cell, the conventional polycrystalline CdS/CdTe cell has few issues that limit device performance. In order to overcome these problems, this study proposes the introduction of poly-CdS to amorphous oxygenated CdS (a-CdS: O) as window layer. The a-CdS: O window material has higher optical band gap (2.5-3.1 eV), better lattice match with CdTe absorber materials and reduced inter-diffusion tendency of CdS and CdTe layers. This book systematically demonstrates the conversion process of poly CdS to a-CdS: O and develops a strategy for the fabrication of suitable a-CdS: O layer to be applied in CdTe solar ce
Download or read book Solar Energy Update written by and published by . This book was released on 1986 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:
