Abstract: A method for improving the minority lifetime of silicon containing wafer having metallic contaminants therein is described incorporating annealing at 1200° C. or greater and providing a gaseous ambient of oxygen, an inert gas and a chlorine containing gas such as HCl.

Abstract: The invention provides a high temperature (about 1150° C. or greater) annealing process for converting thick polycrystalline Si layers on the order of 1 ?m to 40 ?m on a single crystal seed layer into thick single crystal Si layers having the orientation of the seed layer, thus allowing production of thick Si films having the quality of single crystal silicon at high rates and low cost of processing. Methods of integrating such high temperature processing into solar cell fabrication are described, with particular attention to process flows in which the seed layer is disposed on a porous silicon release layer. Another aspect pertains to the use of similar high temperature anneals for poly-Si grain growth and grain boundary passivation. A further aspect relates to structures in which these thick single crystal Si films and passivated poly-Si films are incorporated.

Abstract: A method for improving the minority lifetime of silicon containing wafer having metallic contaminants therein is described incorporating annealing at 1200° C. or greater and providing a gaseous ambient of oxygen, an inert gas and a chlorine containing gas such as HCl.

Abstract: A photolithography method for contacting one or more contact regions of a thin-film semiconductor structure on a transparent supporting material is disclosed. The method comprises the steps of forming one or more openings (6a) in the semiconductor structure (2, 3, 4) to substantially expose respective surface portions (5a) of the supporting material (5) and respective contact regions (4a); covering the surface of the semiconductor structure with a positive photoresist (7); illuminating the semiconductor structure with an exposing light through the supporting material such that first portions of the photoresist covering the substantially exposed surface portions of the supporting material and at least portions of the contact regions respectively are exposed to the exposing light and such that the exposing light is absorbed in the semiconductor structure, leaving one or more second portions of the photoresist covering the semiconductor structure unexposed.