TECHNIQUE FOR FABRICATION OF BACKSIDE ILLUMINATED IMAGE SENSOR

摘要

An array of backside illuminated image sensors is fabricated using a number of processes. These processes include fabricating front side components of the backside illuminated image sensors into or onto a first side of an epitaxial layer disposed over a substrate layer. Dopants are diffused from the substrate through a second side of the epitaxial layer to create a dopant gradient band in the epitaxial layer adjacent to the substrate layer. The backside of the array is then thinned to remove the substrate layer while retaining at least a portion of the dopant gradient band in the epitaxial layer.