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:
Aug. 28, 2001
Filed:
Dec. 18, 1997
Applicant:
Inventors:
Assignee:
Denso Corporation, Kariya, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L 2/976 ; H01L 2/994 ; H01L 3/1062 ; H01L 3/1113 ; H01L 3/1119 ;
U.S. Cl.
CPC ...
H01L 2/976 ; H01L 2/994 ; H01L 3/1062 ; H01L 3/1113 ; H01L 3/1119 ;
Abstract
A wide high concentration P,type region is formed on the surface of an N,type epitaxial layer formed on a P type substrate in the vicinity of the edge portion of a cell region in which a transistor device is formed. As a result, holes generated at the outside of the cell region mostly flow through the P,type region and reach to an emitter electrode. Therefore, the flow amount of the holes does not concentrate on a channel P well for forming a channel region of the transistor device at the cell edge portion, whereby a ruggedness against a latch-up phenomenon can be improved.