Patent ID: 7994554

Claim:
A CMOS image sensor, comprising: an isolation layer on a semiconductor substrate defining an active region, the active region including a photo diode region and a transistor region; a gate on the transistor region, including a gate electrode and a gate insulating layer; a first low-concentration diffusion region in the photo diode region of the substrate; a second low-concentration diffusion region and a high-concentration diffusion region in the transistor region of the substrate, partially overlapping with each other; a buffer layer covering the photo diode region; first and second insulating layers over an entire surface of the substrate, including on the buffer layer in the photo diode region; an insulating sidewall on sides of the gate electrode, including on the first insulating layer in the transistor region and the photo diode region, and on the buffer layer in the photo diode region; and a metal silicide on a surface of the high-concentration diffusion region.