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:
Jan. 21, 1997
Filed:
Sep. 14, 1989
Masami Yamaoka, Anjo, JP;
Shoji Toyoshima, Konan, JP;
Nippondenso Co., Ltd., Aichi-pref., JP;
Abstract
A semiconductor device includes a diode element for protecting a transistor against an overvoltage. A first region of p-type conductivity is formed on an upper surface of an n-type semiconductor substrate in which base and emitter regions of the transistor are formed. A second region of n.sup.+ -type conductivity whose impurity concentration is higher than that of the n-type semiconductor substrate is formed on its upper surface to be spaced apart from the first region. An insulating film is formed to cover the upper surface of the semiconductor substrate. Furthermore, a conductive film is formed to partially overlap the first and second regions through the insulating film. The first region serves as an anode, the second region serves as a cathode, and the conductive film serves as a gate electrode; thus an overvoltage protection diode is obtained.