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. 11, 2025
Filed:
Oct. 25, 2022
Hoya Corporation, Tokyo, JP;
Tatsuya Sasaki, Tokyo, JP;
Masaru Tanabe, Tokyo, JP;
HOYA CORPORATION, Tokyo, JP;
Abstract
A mask blank substrate includes two opposing main surfaces, has a glass material containing SiOand TiO, and has a first region in one main surface side. The first region is a region within a square including a center portion in the one main surface and which is a region extending from the one main surface toward the other main surface up to a position in depth. An inner region of the substrate excluding the first region has a locally non-uniform portion, a ratio of Ti content rate to Si content rate (Ti/Si) of the non-uniform portion differs from Ti/Si of the inner region excluding the non-uniform portion by 0.25% or more, and the variation of Ti content rate in the inner region of the substrate excluding the first region and the non-uniform portion is 0.06 mass % or less.