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:
Sep. 09, 2025
Filed:
Oct. 19, 2020
Hoya Corporation, Tokyo, JP;
Yohei Ikebe, Tokyo, JP;
Osamu Nozawa, Tokyo, JP;
HOYA CORPORATION, Tokyo, JP;
Abstract
Provided is a reflective mask blank comprising a phase shift film having a small change in the phase difference and/or reflectance of the phase shift film even in a case where the film thickness of the phase shift film changes. A reflective mask blank comprises a multilayer reflective film and a phase shift film in this order on a main surface of a substrate. The phase shift film comprises a lower layer and an uppermost layer. The lower layer is located between the uppermost layer and the multilayer reflective film. The lower layer is formed of a material in which the total content of ruthenium and chromium is 90 atomic % or more, or a material in which the total content of ruthenium, chromium, and nitrogen is 90 atomic % or more. The uppermost layer is formed of a material in which the total content of ruthenium, chromium, and oxygen is 90 atomic % or more.