Patent ID: 7411265

Claim:
A photodiode comprising: a first-conduction-type lower region; a second-conduction-type upper region arranged on the lower region; a second-conduction-type electrode contact region of a high concentration arranged at a surface of the upper region, the second-conduction-type electrode contact region arranged to connect to an electrode so as to transmit an output signal; a first-conduction-type first electromagnetic shield region of a high concentration arranged at the surface of the upper region and spaced by an interval from the electrode contact region, wherein the first-conduction-type first shield region is connected to a ground potential; and a first-conduction-type second electromagnetic shield region of a low concentration arranged between the electrode contact region and the first shield region at the surface of the upper region so as to surround the electrode contact region; wherein the first-conduction-type second shield region is connected to the ground potential.