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:
Dec. 25, 2012
Filed:
May. 22, 2009
Kaoru Sakai, Yokohama, JP;
Shunji Maeda, Yokohama, JP;
Kaoru Sakai, Yokohama, JP;
Shunji Maeda, Yokohama, JP;
Hitachi High-Technologies Corporation, Tokyo, JP;
Abstract
The invention relates to a defect inspection apparatus in which images of mutually corresponding areas in identically formed patterns on a sample are compared to detect mismatched portions of the images as defects. The defect inspection apparatus includes an image comparator that creates a feature space with the use of feature quantities calculated from pixels of images acquired under different optical conditions and detects outlier values in the feature space as defects. Thus, the defect inspection apparatus can detect various defects with high sensitivity even if there are luminance differences between images of identical patterns which are attributable to the difference in wafer pattern thickness.