Patent attributes
A novel pixel sensor structure formed on a substrate of a first conductivity type includes a photosensitive device of a second conductivity type and a surface pinning layer of the first conductivity type. An isolation structure is formed adjacent to the photosensitive device pinning layer. The isolation structure includes a dopant region comprising material of the first conductivity type selectively formed along a sidewall of the isolation structure that is adapted to electrically couple the surface pinning layer to the underlying substrate. The corresponding method for forming the dopant region selectively formed along the sidewall of the isolation structure comprises an out-diffusion process whereby dopant materials present in a doped material layer formed along selected portions in the isolation structure are driven into the underlying substrate during an anneal. Alternately, or in conjunction, an angled ion implantation of dopant material in the isolation structure sidewall may be performed by first fabricating a photoresist layer and reducing its size by removing a corner, or a corner portion thereof, which may block the angled implant material.