Light receiving device

Abstract

Abstract PURPOSE:To contrive a decrease in dark current and the improvement in the temperature characteristics of dark current by a method wherein the cathode of the second light receiving element is coupled with the anode of the first light receiving element and photo screening is applied to the cathode of the second light receiving element. CONSTITUTION:Incident light 19 is irradiated at a light receiving element composed of an N type single crystal Si substrate 5 and a P type diffusion region 7 through a window 18 to flow light current IL and dark current Id1. Meanwhile, in the light receiving element composed of a P type diffusion region 6 and an N type diffusion region 8, a dark current Id2 only flows as the light is screened by a light screening layer 17. When the areas of two light receiving elements are set to keep the dark currents Id1 and Id2 almost equal, effective dark current at the output terminal becomes a very small value of Id1-Id2 because the anode of one light receiving element and the cathode of the other light receiving element are connected to a metal wiring layer 11. Furthermore, the temperature characteristics of the effective dark current will be improved by going with the above fact.

Inventors

• 👤 Mitsuo Oshima

Bibliographic Details