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:
Jun. 14, 2016
Shin-etsu Chemical Co., Ltd., Tokyo, JP;
Tsuneo Terasawa, Joetsu, JP;
Hiroshi Fukuda, Joetsu, JP;
Takahiro Kishita, Joetsu, JP;
Daisuke Iwai, Joetsu, JP;
Atsushi Yokohata, Joetsu, JP;
SHIN-ETSU CHEMICAL CO., LTD., Tokyo, JP;
Abstract
A method of inspecting a defect present at a surface portion of a photomask blank having at least one thin film formed on a substrate by use of the inspecting optical system. The method includes setting the distance between the defect and an objective lens of an inspecting optical system to a defocus distance, applying inspection light to the defect through the objective lens, collecting reflected light from the region irradiated with the inspection light, through the objective lens, as a magnified image, identifying a light intensity variation portion of the magnified image, and determining the rugged shape of the defect on the basis of a variation in light intensity of the light intensity variation portion of the magnified image.