Patent ID: 8030608

Claim:
A method for manufacturing a backside illuminated imaging device that performs imaging by receiving light at a back side of a semiconductor substrate to generate electric charges in the semiconductor substrate based on the light and reading out the electric charges from a front side of the semiconductor substrate, the method comprising: forming a first impurity diffusion layer and a fourth impurity diffusion layer in the semiconductor substrate such that the fourth impurity diffusion layer is formed in a direction from a front side surface of the semiconductor substrate to an inner side of the semiconductor substrate and the first impurity diffusion layer having a first conductivity is formed below the fourth impurity diffusion layer, the fourth impurity diffusion layer having a second conductivity and preventing a dark current; forming an insulating layer on the semiconductor substrate in which the first impurity diffusion layer and the fourth impurity diffusion layer are formed; forming an opening in a portion of the insulating layer to expose a portion of a surface of the fourth impurity diffusion layer; forming a second impurity diffusion layer at the exposed portion in the fourth impurity diffusion layer by self-alignment in which the insulating layer serves as a mask; and embedding a conductive material in the opening to form an electrode, wherein a portion except the second impurity diffusion layer of the fourth impurity diffusion layer constitutes a third impurity diffusion layer.