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:
Apr. 24, 2018
Filed:
Sep. 21, 2016
Hoya Corporation, Shinjuku-ku, Tokyo, JP;
Toshiyuki Suzuki, Tokyo, JP;
Shigenori Ishihara, Tokyo, JP;
HOYA CORPORATION, Tokyo, JP;
Abstract
This invention provides a mask blank in which a thin film for transfer pattern formation is provided on a main surface of a transparent substrate. The thin film is made of a material containing a transition metal and silicon and further containing at least one of oxygen and nitrogen. The thin film has as its surface layer an oxide layer with an oxygen content higher than that of a region, other than the surface layer, of the thin film. The thin film is formed so that the thickness of its central portion is greater than that of its outer peripheral portion on the main surface side. The oxide layer is formed so that the thickness of its central portion is greater than that of its outer peripheral portion on the main surface side.