A system and method for image sensing is disclosed. An embodiment comprises a substrate with a pixel region, the substrate having a front side and a backside. A co-implant process is performed along the backside of the substrate opposing a photosensitive element positioned along the front side of the substrate. The co-implant process utilizes a first pre-amorphization implant process that creates a pre-amorphization region. A dopant is then implanted wherein the pre-amorphization region retards or reduces the diffusion or tailing of the dopants into the photosensitive region. An anti-reflective layer, a color filter, and a microlens may also be formed over the co-implant region.