Patent ID: 8003430
Filing Date: 2011-08-23
Classification: H01L,Y02E

Abstract:
1. A method for forming a thin film photovoltaic device, the method comprising: providing a transparent substrate comprising a surface region; forming a first electrode layer overlying the surface region; forming a copper layer overlying the first electrode layer; forming an indium layer overlying the copper layer to form a multi-layered structure; subjecting at least the multi-layered structure to a thermal treatment process in an environment containing a sulfur bearing species; forming a copper indium disulfide material from at least the thermal treatment process of the multi-layered structure, the copper indium disulfide material comprising a copper-to-indium atomic ratio ranging from about 1.2:1 to about 2:1 and a thickness of substantially copper sulfide material having a copper sulfide surface region and a sulfur deficient region characterized by a CuInS removing the thickness of the copper sulfide material to expose a surface region having a copper poor surface comprising a copper to indium atomic ratio of less than about 0.95:1; subjecting the copper poor surface to a sodium species derived from a sodium sulfide material to convert the copper poor surface from an n-type semiconductor characteristic to a p-type semiconductor characteristic; subjecting the sulfur deficient surface region to a sulfide species derived from the sodium sulfide material; subjecting the copper poor surface and the sulfur deficient surface to a treatment process during a time period; and forming a window layer overlying the copper indium disulfide material.