The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 22, 1995
Filed:
Jul. 06, 1994
Goro Sasaki, Yokohama, JP;
Sumitomo Electric Industries Ltd., Osaka, JP;
Abstract
A photodetector of the present invention is devised to reduce the dark current by employing a novel guard ring structure suitable for a mesa type photodiode (PD). Namely, the PD of the present invention has the structure in which a p-type or n-type semiconductor region which is to be a light receiving area is surrounded by a semiconductor region (guard ring) of the same conduction type. A guard ring electrode is formed on the guard ring region and is kept at the same potential as an electrode on a region desired to reduce the dark current. Also, an opto-electronic integrated circuit of the present invention has such a structure that a PD, which is the photodetector of the present invention, and a circuit element such as a transistor are formed on a common semiconductor substrate and that an anode electrode or a cathode electrode of the PD is conductively connected to a gate electrode of a field-effect transistor or to a base electrode of a bipolar transistor.