Photodetector

Abstract

A photodetector includes: a pixel array in which a plurality of pixels are arranged in an array. Each of the plurality of pixels includes: a first semiconductor layer and a second semiconductor layer which are a first conductivity type, the second semiconductor layer located above the first semiconductor layer and having an impurity concentration lower than the impurity concentration of the first semiconductor layer; and a first semiconductor region, of a second conductivity type different from the first conductivity type, which is disposed in the second semiconductor layer and joined to the first semiconductor layer. The first semiconductor layer and the first semiconductor region constitute a multiplication region in which a charge is multiplied by avalanche multiplication. The pixel array includes a first separator of the first conductivity type disposed in the second semiconductor layer and a second separator of the first conductivity type disposed in the first semiconductor layer.

Dependencies are inferred from the claim text.