Semiconductor photodetecting device and method of manufacturing the same

Abstract

A semiconductor photodetecting device is provided for enabling a solid-state image sensor to meet the requirements of higher quality imaging and more reduction in cost. The photodetecting device of the present invention includes: a semiconductor substrate; and an epitaxial layer formed on the semiconductor substrate by epitaxial growth. The epitaxial layer has a multilayer structure including: a first pn junction layer; a first insulating layer; a second pn junction layer; a second insulating layer; and a third pn junction layer. The first insulating layer and the second insulating layer have openings, and the first pn junction layer and the second pn junction layer are adjacent to each other through the openings of the first insulating layer which is placed in between these pn junction layers, and the second pn junction layer and the third pn junction layer are adjacent to each other through the openings of the second insulating layer which is placed in between these pn junction layers. Each of the insulating layers has a periodic structure of refractive indices in the stacking direction as well as a periodic structure of similar-shaped openings which are concentric in the in-plane direction, and therefore has filtering and light condensing functions for the pn junction layer which is formed beneath the insulating layer.