Light receiving device with built-in circuit

摘要

A photodiode converts light incident thereon into an electric signal by a junction between an N-type epitaxial layer and a P-type epitaxial layer with a sufficiently small junction capacitance. The photodiode is surrounded by a P+-type buried isolating diffused layer and a P-type isolating diffused layer, and thus is electrically separated from a signal processing circuit including a MOS transistor.