Patent ID: 8486815

Claim:
A method for fabricating a back-side illumination (BSI) image sensor, comprising: implanting a first type of dopant into an epitaxial layer disposed over a first side of a substrate layer to form a first dopant layer in a first side of the epitaxial layer; adhering a carry layer over the first dopant layer for carrying the substrate layer; grinding a second side of the substrate layer for exposing a second side of the epitaxial layer; implanting the first type of dopant into the epitaxial layer from the second side of the epitaxial layer to form a second dopant layer in the second side of the epitaxial layer, wherein the first dopant layer overlaps the second dopant layer; forming at least one metal layer over the second dopant layer after forming the second dopant layer in the second side of the epitaxial layer; removing the carry layer; and forming a color filtering module over the first dopant layer.