Patent ID: 7611940
Filing Date: 2009-11-03
Classification: H01L

Abstract:
1. A method for manufacturing a CMOS image sensor, comprising the steps of: forming an isolation layer in a semiconductor substrate, defining an active region including a photo diode region and a transistor region; forming a gate insulating layer and a gate electrode on the transistor region; forming a first low-concentration diffusion region in the photo diode region; forming a second low-concentration diffusion region in the transistor region; forming an insulating layer over an entire surface of the substrate; implanting fluorine ions through the insulating layer into an upper surface of the photo diode region and the second low-concentration diffusion region; etching the insulating layer through which fluorine was implanted to form insulating sidewalls on sides of the gate electrode in the transistor region and the photo diode region; forming and patterning a first photoresist layer to expose the transistor region and the insulating sidewall in the transistor region; forming a high-concentration diffusion region in the transistor region partially overlapping with the second low-concentration region using the first photoresist layer and the insulating sidewall in the transistor region as a mask; forming and patterning a second photoresist layer to expose the photo diode region and the insulating sidewall in the photo diode region; and forming a third low-concentration diffusion region on the upper surface of the photo diode region using the second photoresist layer, gate electrode and the insulating sidewall in the photo diode region as a mask, the third low-concentration diffusion region having a conductivity type opposite to the first low-concentration diffusion region.