Patent ID: 7768087

Claim:
A photodiode formed over a silicon substrate, comprising: a light-receiving region formed of a diffusion region of a first conduction type at a surface of the silicon substrate and forming a pn junction with the silicon substrate; an intermediate region formed of a diffusion region of the first conduction type at the surface of the silicon substrate so as to be included in the light-receiving region; a contact region formed of a diffusion region of the first conduction type at the surface of the silicon substrate so as to be included in the intermediate region; a shield layer formed of a diffusion region of a second conduction type in a part of the surface of the silicon substrate outside the intermediate region; and an electrode in contact with the contact region, wherein the shield layer faces a side end part of the diffusion region forming the intermediate region, the intermediate region is in contact with the surface of the silicon substrate between the contact region and the shield layer, and the shield layer is formed laterally around the intermediate region and the intermediate region is absent underneath the shield layer.