Patent ID: 7615399

Claim:
A fabrication method of a complementary metal-oxide semiconductor (CMOS) image sensor, comprising: forming a light-receiving element inside a light sensing region in a substrate; forming at least one transistor which is electrically coupled to the light-receiving element inside a transistor region on the substrate; forming a dielectric layer on the substrate, wherein a metal interconnect line electrically coupled to the transistor is formed in the dielectric layer inside the transistor region; forming a protective layer above the substrate, covering the dielectric layer and the metal interconnect line; removing a portion of the protective layer and a portion of the dielectric layer to form a first opening above the light-receiving element; forming a reflective layer on a sidewall of the first opening, wherein the reflective layer comprises a conductive layer and is formed as a whole after the first opening is formed; forming a transparent material layer, covering the protective layer and the reflective layer and filling the first opening; forming an optical filter on the transparent material layer; and forming a converging element on a portion of the optical filter inside the light sensing region.