Patent ID: 9472584
Filing Date: 2016-10-18
CPC Classification: H01L

Claim Text:
1. A phototransistor comprising a first emitter region, a first base region having at least a portion exposed to a light-receiving side, and a first collector region in this order from the light-receiving side in a depth direction, wherein the first collector region includes a second collector region and a third collector region that is in contact with a downstream side of the second collector region in the depth direction and has a resistance lower than that of the second collector region, the phototransistor further comprises a first region that is spaced away from the first base region at an outer side of the first base region on a light-receiving side surface thereof, the first region having a conductivity type opposite to that of the first collector region, and the first region is grounded, and wherein the phototransistor further comprises a collector contact region at an outer side of the first region on the light-receiving side surface thereof, the collector contact region being electrically connected to the first collector region, and wherein a depletion layer is formed between the first region and the collector contact region.