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. 27, 2024
Filed:
Apr. 11, 2022
Applicant:
Agc Inc., Tokyo, JP;
Inventors:
Assignee:
AGC INC., Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
G03F 1/24 (2012.01); G03F 1/52 (2012.01); G03F 1/54 (2012.01);
U.S. Cl.
CPC ...
G03F 1/24 (2013.01); G03F 1/52 (2013.01); G03F 1/54 (2013.01);
Abstract
A reflective mask blank includes a substrate and, on or above the substrate in order, a reflective layer for reflecting EUV light, a protective layer for protecting the reflective layer, and an absorbent layer for absorbing EUV light. The absorbent layer has a reflectance for a wavelength of 13.53 nm of from 2.5% to 10%. A film thickness d of the absorbent layer satisfies a relationship of: where the integer i is 0 or 1, and dis represented by: where n is a refractive index of the absorbent layer, k is an absorption coefficient of the absorbent layer, and INT(x) is a function of returning an integer value obtained by truncating a decimal part.