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:
Nov. 25, 1997
Filed:
Apr. 22, 1996
Applicant:
Inventor:
Shigeharu Matsumoto, Tokyo, JP;
Assignee:
NEC Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
437 69 ; 437 80 ;
Abstract
An obstacle layer is grown on an inner surface of a mask structure defining a first opening over a first area assigned to a thick field oxide layer during a growth of the thick field oxide layer, and prevents a silicon substrate beneath a peripheral area of the thick field oxide layer from a dopant impurity implanted through the thick field oxide layer into the silicon substrate beneath the central area of the thick field oxide layer so that a channel stopper is never exposed to a major surface of the silicon substrate outside of the thick field oxide layer.