Patent ID: 8278690

Claim:
A backside illuminated (“BSI”) complementary metal-oxide semiconductor (“CMOS”) image sensor, comprising: an array of photosensitive regions along with pixel circuitry disposed in or on a first region of a semiconductor layer, the photosensitive regions sensitive to light incident on a backside of the BSI CMOS image sensor; peripheral circuitry disposed in or on a second region of the semiconductor layer; a dopant layer disposed in a backside of the semiconductor layer; and an anti-reflection layer disposed on the dopant layer and extending under the first region of the semiconductor layer while not extending under the second region of the semiconductor layer, wherein a first portion of the dopant layer covered by the anti-reflection layer is activated to encourage charge carriers to migrate towards the photosensitive regions within the first region of the semiconductor layer and a second portion of the dopant layer not covered by the anti-reflection layer is an unactivated high recombination region for charge carriers.