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:
Feb. 03, 1981
Filed:
Nov. 16, 1978
Bernard Roger, Carpiquet, FR;
U.S. Philips Corporation, New York, NY (US);
Abstract
The invention relates to a mesa transistor comprising a highly doped substrate, on which there is provided a lower doped collector region of the same conductivity type, a base zone of the opposite conductivity type provided on said collector region and an emitter zone provided in the base region with the mesa being formed by a recess in a flat upper face of the semiconductor plate which recess fully encloses the base zone and extends into the substrate. According to the invention the recess consists of a first portion extending over a part of the thickness of said collector region only, and a groove extending from the bottom of this first portion into the substrate. The wall and the bottom of this last-mentioned groove preferably everywhere adjoin a thin, highly doped semiconductor zone of the same conductivity type as the substrate.