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:
May. 24, 2011
Filed:
Oct. 08, 2008
Keiko Morishita, Yokohama, JP;
Shingo Kanamitsu, Kawasaki, JP;
Keiko Morishita, Yokohama, JP;
Shingo Kanamitsu, Kawasaki, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
In a pattern evaluation method of determining whether a pattern formed on a photomask is acceptable, an aberration parameter of an image quality evaluation apparatus for determining a pattern image intensity in transferring a pattern formed on a photomask onto a wafer is acquired. An acceptance criterion value used in determining whether an abnormal pattern of the photomask including the effect of aberration of the image quality evaluation apparatus is acceptable is set through a lithographic simulation using the acquired aberration parameter. Then, using the image quality evaluation apparatus, an image intensity of the abnormal pattern of the photomask and an image intensity of a normal pattern corresponding to the abnormal pattern are obtained. It is determined whether the difference between the two acquired image intensities is within the set acceptance criterion value.