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:
Feb. 21, 2012
Filed:
Feb. 27, 2009
Ayumi Minamide, Tokyo, JP;
Akemi Moniwa, Tokyo, JP;
Junjiro Sakai, Tokyo, JP;
Manabu Ishibashi, Itami, JP;
Ayumi Minamide, Tokyo, JP;
Akemi Moniwa, Tokyo, JP;
Junjiro Sakai, Tokyo, JP;
Manabu Ishibashi, Itami, JP;
Renesas Electronics Corporation, Kawasaki-shi, JP;
Abstract
A photomask is disclosed which can suppress deterioration of the depth of focus even in the case where main features are arranged randomly. Sub-features are replaced by a quadrangular sub-feature located inside an external quadrangle which includes as part of its outer periphery the outermost portions of the original sub-features. The sub-feature after the replacement is preferably in a square shape and the length of one side thereof is determined in accordance with the length of the associated external quadrangle. A central position of the sub-feature after the replacement is preferably coincident with the center of the external quadrangle or the center of gravity of the region which includes the original sub-features.