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:
Feb. 17, 2015
Filed:
Aug. 30, 2012
Toshiyuki Uno, Tokyo, JP;
Kazuyuki Hayashi, Tokyo, JP;
Toshiyuki Uno, Tokyo, JP;
Kazuyuki Hayashi, Tokyo, JP;
Asahi Glass Company, Limited, Tokyo, JP;
Abstract
To provide an EUV mask blank provided with a low reflective layer, which has excellent properties as an EUV mask blank. A reflective mask blank for EUV lithography comprising a substrate, and a reflective layer for reflecting EUV light, an absorber layer for absorbing EUV light and a low reflective layer to an inspection light (wavelength: 190 to 260 nm) for a mask pattern, formed in this order on the substrate, wherein the low reflective layer has a stacked structure having a first layer containing at least 95 at % in total of silicon (Si) and nitrogen (N), and a second layer containing at least 95 at % in total of tantalum (Ta), oxygen (O) and nitrogen (N) or a second layer containing at least 95 at % in total of tantalum (Ta) and nitrogen (N), stacked in this order from the absorber layer side.