Patent ID: 7084000

Claim:
A method for manufacturing a solid-state imaging device comprising a semiconductor substrate; a photoelectric conversion portion formed on the semiconductor substrate; a gate insulating film formed on the semiconductor substrate and covering the photoelectric conversion portion; a vertical transfer portion for transferring a charge generated at the photoelectric conversion portion in a vertical direction; and a multilayer transfer gate electrode for transferring the charge of the vertical transfer portion; wherein at least one layer of the multilayer transfer gate electrode is made of at least two impurity doped amorphous silicon films of different impurity concentration; and wherein the impurity doped amorphous silicon films are formed by: a step of forming a first doped amorphous silicon film with a first impurity concentration; a step of etching the first doped amorphous silicon film into the shape of the transfer gate electrode; a step of forming a second doped amorphous silicon film with a second impurity concentration; and a step of etching the second doped amorphous silicon film into the shape of the transfer gate electrode.