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:
Nov. 28, 2017
Filed:
Sep. 02, 2016
Shin-etsu Chemical Co., Ltd., Tokyo, JP;
Tsuneo Terasawa, Joetsu, JP;
Atsushi Yokohata, Joetsu, JP;
Daisuke Iwai, Joetsu, JP;
Takahiro Kishita, Joetsu, JP;
Hiroshi Fukuda, Joetsu, JP;
SHIN-ETSU CHEMICAL CO., LTD., Tokyo, JP;
Abstract
Disclosed is a method of inspecting a defect present at a surface portion of a photomask blank which includes an optical film, and a thin film. The method includes: selecting and designating an inspection treatment procedure and a criterion for determination of rugged shape of the defect which correspond to modes of the optical film and the thin film of the photomask blank; applying inspection light to a region including the defect while maintaining a distance between the defect and an objective lens of an inspecting optical system, based on the designated inspection treatment procedure, and collecting reflected light from the region irradiated with the inspection light, as a magnified image of the region, through the inspecting optical system; and determining the rugged shape of the defect, from light intensity distribution of the magnified image, based on the designated criterion for determination.