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:
Mar. 21, 1978
Filed:
Nov. 17, 1975
Applicant:
Inventor:
Chang K Chu, Pittsburgh, PA (US);
Assignee:
Westinghouse Electric Corporation, Pittsburgh, PA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
357 38 ; 357 20 ; 357 55 ; 357 68 ; 357 86 ; 3072 / ;
Abstract
A reverse switching rectifier is described in which a PNPN semiconductor structure has a specially adapted N-type end zone or cathode-emitter zone. The N-type end zone penetrates to two different levels in the semiconductor body. A deep central portion and a shallow peripheral portion of the N-type end zone are produced by etching a cavity in the center of the body followed by diffusion of N-type dopant material. The exposed surfaces of the N-type end zone are then metallized to provide electrical and thermal contact thereto.