Patent ID: 7541210

Claim:
A method for fabricating a CMOS image sensor comprising: forming a photodiode region corresponding to a first source and drain region of a transistor and a second conductive type ion region on a surface of a first conductive type substrate by implanting a second conductive type impurity ion into an entire surface of the substrate where the transistor is to be formed; forming spacers at both sides of a gate electrode of the transistor after forming the second conductive type ion region; forming a second conductive type lightly doped ion region in the substrate deeper than the second conductive type ion region corresponding to the photodiode region by lightly implanting a second conductive type impurity ion only in an area where the photodiode region is opened by a photoresist film; forming a first conductive type ion region thinner than the second conductive type ion region on the surface of the substrate corresponding to the photodiode region by implanting a first conductive type impurity ion only in the area where the photodiode region is opened by the photoresist film; and forming a diffusion region diffused into the surface of the substrate in the photodiode region by diffusing the second conductive type lightly doped ion region into the second conductive type ion region by a thermal process.