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:
Oct. 14, 1997
Filed:
Dec. 24, 1996
Applicant:
Inventor:
Hitoshi Abiko, Tokyo, JP;
Assignee:
NEC Corporation, Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
437 67 ; 437 63 ; 437 64 ; 148D / ;
Abstract
When an isolating oxide is formed in a silicon substrate, a side wall is formed on the inner wall of a mask consisting of a lower silicon oxide layer and an upper silicon nitride layer for forming a groove in the silicon substrate in such a manner as to be laterally spaced from the inner wall of the upper silicon nitride layer, and the isolating oxide is formed from a silicon oxide layer deposited over the mask after removal of the side wall by using a polishing, thereby preventing the isolating oxide from undesirable side etching during an etching step for the lower silicon oxide layer.