Trench isolation regions in image sensors

Abstract

Trenches are formed in a substrate or layer and a solid source doped with one or more dopants is deposited over the image sensor such that the solid source fills the one or more trenches and is disposed on the surface of the substrate. The surface of the image sensor is then planarized so that the solid source remains only in the trenches. A thermal drive operation is performed to cause at least a portion of the one or more dopants in the solid source to diffuse into the portions of the substrate or layer that are immediately adjacent to and surround the sidewall and bottom surfaces of the trenches. The diffused dopant or dopants form passivation regions that passivate the interface between the substrate or layer and the sidewall and bottom surfaces of the trenches.

Dependencies are inferred from the claim text.