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:
Jul. 26, 2005
Filed:
Dec. 14, 2001
Haruo Furuta, Tokyo, JP;
Tomohiro Yamashita, Tokyo, JP;
Haruo Furuta, Tokyo, JP;
Tomohiro Yamashita, Tokyo, JP;
Renesas Technology Corp., Tokyo, JP;
Abstract
A semiconductor device and a manufacturing method therefor reduce the occurrence of variation in threshold voltage of a MOS transistor formed by a dual oxide process, thereby to improve manufacturing yield. On the main surface of a semiconductor substrate (), gate oxide films (GX, GX) of different thickness are located in active regions (A,B), respectively, and gate electrodes (GT, GT) are located on top of the gate oxide films (GX, GX), respectively. An isolation insulating film () which defines the active region (A) in a thick-film portion (AR) has an excessively removed edge portion on the side of a MOS transistor () and thereby a recessed portion (DP) is formed in the edge portion of the active region (A). On the other hand, an edge portion of the isolation insulating film () in a thin-film portion (BR) on the side of a MOS transistor () is not excessively removed.