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. 16, 2013
Filed:
Aug. 04, 2010
Yasunobu Kai, Kanagawa-ken, JP;
Yasunobu Kai, Kanagawa-ken, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
In one embodiment, a photomask designing method for creating a pattern layout having an assist pattern placed around a design pattern is disclosed. The method can place a plurality of evaluation points around the design pattern and set an evaluation index for imaging properties of the design pattern on an imaging surface. The method can combine a light intensity distribution of the design pattern with light intensity distributions of the evaluation points to obtain a light intensity distribution on the imaging surface and evaluate the light intensity distribution on the imaging surface using the evaluation index to determine a region having an effective evaluation point placed. In addition, the method can determine a placement condition for the assist pattern based on the region where the effective evaluation point is placed and place the assist pattern around the design pattern based on the placement condition to create the pattern layout.