Thin film photovoltaics

Copper Indium Diselenide. CuInSe2 (CIS) has proven to be one of the most promising thin-film photovoltaic materials. CIS ahoy materials have yielded smah-area (ca 1 cm ) laboratory devices with efficiencies in excess of 17% and large-area (ca 0.5 m ) monolithic integrated modules with efficiencies in excess of 11%, and have shown excehent radiation hardness. 

Selenium is also used in thin-film photovoltaic cells (qv) which contain copper indium diselenide [12018-95-0] CuInSe2. Use is quite small as of 1996. However, if the United States solar energy output with such cells were to increase by 100 MW/yr, this would require 8 t of selenium aimuaHy (see... 

Thin film photovoltaic devices (CdTe is a direct bandgap semiconductor with a bandgap energy of 1.5 eV at room temperature). 

Copper-indium diselenide, CuInSe2 (CIS), is a widely electrodeposited compound, due to its significance in thin film photovoltaics. 

Mitzi, D. B. Yuan, M. Liu, W. Kellock, A. Chey, S. J. Deline, V. Schrott, A. G. 2008. A high-efficiency solution-deposited thin-film photovoltaic device. Adv. Mater. 20 3657-3662. 

Figure 6.2. Predicted efficiency versus band gap for thin-film photovoltaic materials for solar spectra in space (AMO) and on the surface of the Earth (AMI.5) at 300K, with unconcentrated (C = 1) and high concentration (C = 1000) sunlight.

Hoffman, D. J. Kerslake, T. W. Hepp, A. F. Jacobs, M. K. Ponnusamy, D. 2000. Thin-film photovoltaic solar array parametric assessment. Proceedings of the 35th Intersociety Energy Conversion Engineering Conference (IECEC 35). IEEE, Piscataway, NJ. pp. 670-680. 

F.R. Zhu, P. Jennings, J. Cornish, G. Hefter, and K. Luczak, Optimal and optical design of thin-film photovoltaic devices, Sol. Energy Mater. Sol. Cells, 49 163-169, 1997. 

Avachat US, Jahagirdar AH, Dheere NG (2006) Multiple band gap combination of thin film photovoltaic cell and a photoanode for efficient hydrogen and oxygen generation by water splitting. Sol Energy Mat Sol Cells 90 2464-2470... 

In spite of this extreme experimental simplicity, nnderstanding the mechanisms involved in the deposition and the ability to widen the range of deposits obtained—both in composition and the control of numerous other properties—is usually not so simple. Also in spite of its simplicity, it has not been exploited as a techniqne as mnch as might be expected. However, CD has experienced somewhat of a renaissance recently, due largely to its overwhelmingly snccessfnl nse in depositing bnffer layers of CdS (and similar materials) in thin-film photovoltaic cells. The deposition of the CdS, as with many other semiconductors that have been deposited by CD, is often recipe oriented there seem to be almost as many different recipes as there are groups. 

Probably the most important factor responsible for the renewal of interest in the CD technique is the almost universal use of CD CdS films in thin-film photovoltaic cells based on either Cu(Ga)lnSe2 (abbreviated here as CIS, which in-... 

Today, the the most important application for CD films is the use of CD CdS as the window (or buffer) layer in thin-film photovoltaic cells [16]. Both CdTe- and CulnSci-type absorber films use this procedure. Such cells have reached the pilot plant stage, and there appears to be no obvious competitor for the CD CdS at present. 

Chemical deposition of ZnS has been the subject of considerable activity, the main reason for which is its hoped-for substitution for CdS in thin-film photovoltaic cells. Since the chemistries of Zn and Cd are similar in many ways, it might be expected that deposition of their chalcogenides is also similar. However, there is a dominant difference in their properties that results in the fact that ZnS is considerably more difficult to deposit by CD than CdS. This difference is manifested by the difference in solubility products between the respective hydroxides and chalcogenides. Considering, for example, the sulphides, the relevant values of K p are ... 

CuInSi (and, even more, CuInSei) are strong candidates for thin-film photovoltaic cells. For this purpose, the chalcopyrite structure (which is an ordered lattice) is preferred over the disordered, zincblende form. Due to the large absorption coefficients of these materials, a 1-iJim-thick film is more than enough to absorb almost all the suprabandgap radiation. Somewhat thicker films are generally used, due to problems of pinholes, which commonly occur in thinner films. A number of methods have been used to deposit these films. Surprisingly, very few (published) attempts have been made to deposit them by CD. 

Perhaps the most promising area of photovoltaic research involves thin-film photovoltaic cells. These cells are not produced from expensive crystalline silicon. Rather, they are formed as vaporized silicon or some other photovoltaic material is deposited on a glass or metal substrate. The resulting films are about 400 times thinner than traditional silicon wafers, which saves in material costs. Furthermore, the films are easy to mass-produce. 

Amorphous Silicon An alloy of silica and hydrogen, with a disordered, noncrystalline internal atomic arrangement, that can be deposited in thin layers (a few micrometers in thickness) by a number of deposition methods to produce thin-film photovoltaic cells on glass, metal or plastic substrates. 

Ullal, H.S., K. Zweibel, and B. von Roedem. 2002. Polyciystalline Thin Film Photovoltaics Research, Development, and Technologies. Paper presented at 29th Institute of Electrical and Electronics Engineers Photovoltaic Specialists Conference (IEEE PVSC), New Orleans, La., May... 

Solar Crystalline and thin film photovoltaic cells (includes frames and supports) Wind fiberglass blade turbines (includes mechanical parts and scrapping the turbine at the end of its life) 30 years 20 years 2- 3 years 3- 4 months 10 20... 

Harrop P. (2007) The global situation with printed and thin film photovoltaic beyond silicon, IDTechEx Conference — Printed Electronics Asia 2007. 

Green, M.A. Thin-film photovoltaics. Adv. Solar Energy 2003, 15, 187-213. 

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