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. 27, 2007
Filed:
Oct. 29, 2004
Mari Inoue, Yokohama, JP;
Mari Inoue, Yokohama, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
A photomask evaluating method comprises calculating a killer defect rate function with respect to a simulative defect pattern including a pattern of photomask and a plurality of defects, the killer defect rate function representing a killer defect rate of the simulative defect pattern with respect to a desired density of the pattern and a desired size of the plurality of defects, calculating the number of killer defects in an inspection region of the photomask based on an area of the photomask inspection region, a pattern density in the inspection region, the killer defect rate function and a defect size distribution representing the number of defects per unit area to a defect size range acquired from a photomask manufacturing step, and evaluating the photomask based on the calculated number of the killer defects.