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:
May. 06, 1997
Filed:
Mar. 01, 1995
Susumu Murakami, Katsuta, JP;
Yoshiteru Shimizu, Katsuta, JP;
Takeshi Yokota, Hitachi, JP;
Yasuhiro Mochizuki, Katsuta, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A novel semiconductor device with a pair of main surfaces is disclosed, in which at least three semiconductor layers are formed adjacently to each other. The device comprises a main thyristor portion for supplying a main current, an auxiliary thyristor portion, a pilot thyristor portion and a breakover portion. The breakover portion, in turn, includes a semiconductor layer having a high impurities concentration formed on one of the main surfaces, and a plurality of semiconductor layers having a high impurities concentration of opposite conduction type formed adjacently to the semiconductor layer and in spaced relationship from each other.