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. 30, 1999
Filed:
Sep. 10, 1998
Shingo Hashimoto, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A semiconductor device includes a first conductivity type low concentration impurity layer provided around a thick silicon oxide film, which is formed for element isolation in a first conductivity type element region as a surface region in a semiconductor substrate, and a second conductivity type impurity layer which is provided immediately under at least the thick silicon oxide film. The second conductivity type impurity layer constitutes a channel stopper to enhance the effect of element isolation. The first conductivity type low concentration impurity layer has an effect of improving the P-N junction breakdown voltage of an active region in the first conductivity type element region, and suppresses the narrow channel effect of a MOS transistor in the first conductivity type element region.