Patent ID: 8120078

Claim:
A photodiode structure comprising: a semiconductor of a first conductivity type, the semiconductor having a main surface; a first well formed in the semiconductor at the main surface, the first well being of a second conductivity type opposite to the first conductivity type; a second well formed in the semiconductor at the main surface laterally outside the first well, the second well being of the second conductivity type; a first terminal electrically connected to the first well and the second well; a second terminal electrically connected to the semiconductor such that a depletion region of laterally varying distance to the main surface results from applying a reverse voltage to the first and second terminals; and an optically transmissive layer overlaying the first and second wells so that the first and second wells receive light incident onto the photodiode structure such that a depletion region associated with both wells contributes to a photocurrent generated by the photodiode structure.