Embodiments of a process including depositing a sacrificial layer on the surface of a substrate over a photosensitive region, over the top surface of a transfer gate, and over at least the sidewall of the transfer gate closest to the photosensitive region, the sacrificial layer having a selected thickness. A layer of photoresist is deposited over the sacrificial layer, which is patterned and etched to expose the surface of the substrate over the photosensitive region and at least part of the transfer gate top surface, leaving a sacrificial spacer on the sidewall of the transfer gate closest to the photosensitive region. The substrate is plasma doped to form a pinning layer between the photosensitive region and the surface of the substrate. The spacing between the pinning layer and the sidewall of the transfer gate substantially corresponds to a thickness of the sacrificial spacer. Other embodiments are disclosed and claimed.