ABSTRACT
Antireflection coatings are an important part of all solar cells. Titanium and tantalum oxides are customary coatings which are deposited either from solutions or by sputtering. The United States Department of Energy-supported research and development on solar cells has given a decisive push to the realization of useful photovoltaic energy sources. This work is well documented in the regularly published proceedings of the IEEE Photovoltaics Specialists Conferences and the European Community Photovoltaic Solar Energy Conferences. The best monocrystalline material with a high carrier lifetime is most suitable for high efficiency and stable solar cells. Contact spacing is technically accessible for carrier lifetimes in the micron range. In larger photovoltaic energy systems the cell efficiency is the most important factor. The higher the efficiency reduced costs for building and maintaining of the power station. Progress in solar cell technology was coupled with progress in concentrator design. Fresnel-type concentrators were applied to silicon solar cells and later to GaAs solar cells.
