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:
Sep. 22, 1992
Filed:
Mar. 04, 1988
Applicant:
Inventor:
Takashi Hosaka, Tokyo, JP;
Assignee:
Seiko Instruments Inc., , JP;
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
437 72 ; 437980 ;
Abstract
An isolation method which enables bird's beaks to be reduced and which also permits a reduction in the number of defects is disclosed. A masking layer which masks against field oxidation comprises a polycrystalline silicon film covered with silicon nitride films. The surface of the semiconductor substrate which is not masked by the masking layer is subjected to an oxidation treatment to form an element isolation region.