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. 30, 1993
Filed:
Jul. 07, 1992
Applicant:
Inventors:
Sridhar Divakaruni, South Burlington, VT (US);
Badih El-Kareh, Austin, TX (US);
Eric D Johnson, Westford, VT (US);
Assignee:
International Business Machines Corporation, Armonk, NY (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
437 32 ; 437 28 ; 437917 ; 437162 ; 148D / ;
Abstract
A high performance PNP lateral bipolar transistor is described, incorporating at least two trenches extending from the upper P.sup.- surface of a semiconductor substrate almost to a buried N.sup.+ layer. The floor of one trench is heavily N-doped to establish a connection between the buried N.sup.+ layer and an N.sup.- diffusion in the walls of the trench. When the trenches are backfilled with P.sup.+ polysilicon a lateral PNP is formed having a buried base contact.