Polyerystalline silicon thin-film solar cells on various substrates

Thin-film polycrystalline silicon solar cells have been fabricated on various substrates, such as inactive P++ mono-crystalline silicon substrates, p(++) mono-Si substrates covered by thermally oxidized SiO2 and ceramic substrates by means of a rapid thermal chemical vapour deposition (RTCVD) technique. Zone melting recrystallization (ZMR) was applied in the process in order to enlarge the grain size of the deposited silicon thin film. The deposition conditions were studied. The scanning rate of the ZMR process was investigated. The best conversion efficiency of 15.12% (AM1.5G, 24.5 degrees C) has been achieved on inactive P++ mono-crystalline silicon substrates without cell surface texture and 10.21% (AM1.5, 24.5 degrees C) on p(++) c-Si substrates covered by thermally oxidized SiO2 with the cell area of 1.07 cm(2). The polycrystalline silicon thin film was also deposited on Al2O3 substrates by a RTCVD process. A simple ZMR process was used without any intermediate layer and cap layers. The maximum grain size of the silicon thin film was about one millimeter in width and a few millimeters in length after ZMR. (c) 2006 WILEY-VCH Veriag GmbH & Co. KGaA, Weinheim.