The absorption of moisture from a wall surface of an apertured part formed in an interlayer insulating film in accordance with a light-receiving part of a light detector is minimized and deterioration of wiring in the interlayer insulating film is prevented. A position that corresponds to a light-receiving part 52 of a wiring-structure layer 90 obtained by layering an Al layer and an interlayer insulating film composed of SOG or another material is etched, and an apertured part 120 is formed. A silicon nitride film 130 is then deposited on a side-wall surface and bottom surface of the apertured part 120 via CVD. The silicon nitride layer 130 prevents moisture from infiltrating the wiring-structure layer 90.