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:
Apr. 23, 2013
Filed:
Jul. 21, 2011
Ayumi Minamide, Kanagawa, JP;
Mitsuru Okuno, Kanagawa, JP;
Akemi Moniwa, Kanagawa, JP;
Manabu Ishibashi, Itami, JP;
Ayumi Minamide, Kanagawa, JP;
Mitsuru Okuno, Kanagawa, JP;
Akemi Moniwa, Kanagawa, JP;
Manabu Ishibashi, Itami, JP;
Renesas Electronics Corporation, Kanagawa, JP;
Abstract
A photomask is provided which can have a large depth of focus even if four main features are annularly arranged at random. The photomask has four annularly arranged main features based on design information of a circuit feature to be formed on a wafer, and a sub-feature is laid at an intersection point of two diagonal lines of a quadrangle formed by four vertices inside the four main features in order to increase a depth of focus of an exposure feature. Therefore, the depth of focus can be increased even if the main features are not arranged at a constant pitch.