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:
Dec. 08, 2015
Filed:
Dec. 19, 2013
Asahi Glass Company, Limited, Chiyoda-ku, JP;
Asahi Glass Company, Limited, Chiyoda-ku, JP;
Abstract
A process for producing a reflective mask blank for EUV lithography (EUVL), which comprises forming a multilayer reflective film for reflecting EUV light on a film-forming surface of a substrate, then forming a protective layer for protecting the multilayer reflective film, on the multilayer reflective film, and forming an absorber layer for absorbing EUV light, on the protective layer, to produce a reflective mask blank for EUVL, wherein the multilayer reflective film is a Mo/Si multilayer reflective film, the protective layer is a Ru layer or a Ru compound layer, the absorber layer is a layer containing at least Ta and N, and after forming the Mo/Si multilayer reflective film, the protective layer is formed, and after forming a Si thin film or Si oxide thin film having a thickness of at most 2 nm on the protective layer, the absorber layer is formed.