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:
Jul. 24, 2012
Filed:
Apr. 26, 2011
Kazuyuki Hayashi, Tokyo, JP;
Kazuyuki Hayashi, Tokyo, JP;
Asahi Glass Company, Limited, Tokyo, JP;
Abstract
A reflective mask blank for EUV lithography having a low-reflective layer which has a low reflectivity with respect to wavelengths of EUV light and a mask pattern inspection light and which satisfies a predetermined reflectivity (405 nm: <40%, 600 to 650 nm: 30 to 50%, 800 to 900 nm: >50%, 1,000 to 1,200 nm: <90%) in a wavelength region (400 to 1,200 nm) required for the mask production process and the pattern transcription process. A reflective mask blank for EUV lithography having a reflective layer for reflecting EUV light, an absorbing layer for absorbing EUV light and a low-reflective layer with respect to a mask pattern inspection light (wavelength: 190 to 260 nm), which are formed in this order on a substrate, wherein the low-reflective layer contains at least tantalum (Ta), oxygen (O) and hydrogen (H), and the low-reflective layer has a Ta+O total content that is between 85 and 99.9 at % and an H content that is between 0.1 and 15 at %.