Backside illuminated image sensors and method of making the same

摘要

A backside illuminated image sensor includes a substrate with a substrate depth, where the substrate includes a pixel region and a peripheral region. The substrate further includes a front surface and a back surface. The backside illuminated image sensor includes a first isolation structure formed in the pixel region of the substrate, where a bottom of the first isolation structure is exposed at the back surface of the substrate. The backside illuminated image sensor includes a second isolation structure formed in the peripheral region of the substrate, where the second isolation structure has a depth less than a depth of the first isolation structure. The backside illuminated image sensor includes an implant region adjacent to at least a portion of sidewalls of each isolation structure in the pixel region.

主权项

1. A backside illuminated image sensor, comprising:
a substrate comprising a pixel region and a peripheral region, wherein the substrate includes a front surface and a back surface; a first isolation structure formed in the pixel region of the substrate, wherein a bottom of the first isolation structure is exposed at the back surface of the substrate; a second isolation structure formed in the peripheral region of the substrate, wherein the second isolation structure has a depth less than a depth of the first isolation structure; and an implant region adjacent to at least a portion of sidewalls of each isolation structure in the pixel region, wherein the portion of the sidewalls are located closer to the back surface than a top surface of the substrate, wherein the second isolation structure is free of the implant region.