Patent ID: 9419159
Filing Date: 2016-08-16
CPC Classification: H01L,Y02E,Y02P

Claim Text:
1. A back-illuminated type semiconductor light-detecting element comprising: a silicon substrate having a pn junction comprised of a semiconductor region of a first conductivity type and a semiconductor region of a second conductivity type, wherein on the silicon substrate, an accumulation layer of the first conductivity type is formed on a principal surface side of the silicon substrate and an irregular asperity is formed in at least a region opposed to the pn junction in the principal surface, wherein the region opposed to the pn junction in the principal surface of the silicon substrate is optically exposed, wherein the principal surface where the irregular asperity is formed constitutes a light incident surface, light incident from the principal surface travels in the silicon substrate, the irregular asperity is formed by applying a pulsed laser beam, and light traveling in the silicon substrate is scattered, diffused, or reflected by the irregular asperity, and wherein a thickness of the accumulation layer of the first conductivity type is larger than a height difference of the irregular asperity.