Patent ID: 8921187
Filing Date: 2014-12-30
Classification: H01L

Abstract:
1. A process comprising: forming a photosensitive region near a surface of a substrate; forming a transfer gate on the surface of the substrate adjacent to the photosensitive region, the transfer gate including a top surface and a pair of sidewalls; depositing a sacrificial layer on the surface of the substrate over the photosensitive region, on the top surface of the transfer gate, and at least the sidewall of the transfer gate closest to the photosensitive region, the sacrificial layer having a selected thickness; depositing a layer of photoresist over the sacrificial layer; patterning and etching the layer of photoresist and the sacrificial layer to expose the surface of the substrate over the photosensitive region and at least part of the top surface of the transfer gate while leaving the sacrificial layer on the sidewall of the transfer gate closest to the photosensitive region to form a sacrificial spacer; plasma doping the substrate to form a pinning layer between the photosensitive region and the surface of the substrate; and stripping the photoresist layer and the sacrificial spacer to expose the sidewall of the transfer gate closest to the photosensitive region, the spacing between the pinning layer and the sidewall of the transfer gate closest to the photosensitive region substantially corresponding to a thickness of the sacrificial spacer.