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:
Mar. 24, 2015
Filed:
Mar. 15, 2013
Kabushiki Kaisha Toshiba, Tokyo, JP;
Tsuneo Terasawa, Tokyo, JP;
Takeshi Yamane, Tsukuba, JP;
Tsuneo Terasawa, Ome, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Dai Nippon Printing Co., Ltd., Tokyo, JP;
Abstract
According to one embodiment, a method of inspecting a mask substrate for defects, includes acquiring a defocus image of a partial region of a mask substrate using a dark-field optical system, acquiring a just-focus image of the partial region using the dark-field optical system, generating a set composed of first signals obtained from the defocus image and having signal intensities equal to or higher than a first threshold value, excluding, from the set, the first signals pertaining to parts in which signal intensities of signals obtained from the just-focus image are equal to or higher than a second threshold value, determining an inspection threshold value for signal intensities, on the basis of the first signals not excluded from, and remaining in, the sea.