Patent ID: 7572701
Filing Date: 2009-08-11
Classification: H01L

Abstract:
1. A method of forming an active pixel sensor (APS) cell structure comprising the steps of: a. etching a trench into a semiconductor substrate to define a recessed portion of said APS cell structure below a substrate surface; b. forming a layer of dielectric material over said recessed portion; c. filling said recessed portion with a conductive material atop said dielectric material layer to form a gate conductor; d. forming a doped pinning layer comprising material of a first conductivity type in said substrate at a first side of said gate conductor; e. forming a doped collection well layer comprising material of a second conductivity type beneath said doped pinning layer; and, f. forming a doped diffusion layer of a second conductivity type in said substrate having at least a portion formed at said surface of said substrate and adjacent a second side of said gate conductor, said recessed portion of said gate conductor forming a channel region enabling charge transfer between said collection well layer and said diffusion region,