To accomplish both of higher performance of a crystal and lower cost in a semiconductor member, and to produce a solar cell having a high efficiency and a flexible shape at low cost, the semiconductor member is produced by the following steps, (a) forming a porous layer in the surface region of a substrate,...http://www.google.de/patents/US6756289?utm_source=gb-gplus-sharePatent US6756289 - Method of producing semiconductor member and method of producing solar cell
