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:
Jun. 01, 2021
Filed:
Feb. 13, 2019
Hoya Corporation, Tokyo, JP;
HOYA CORPORATION, Tokyo, JP;
Abstract
Provided is a mask blank for a phase shift mask including an etching stopper film. A mask blank has a structure where a transparent substrate has layered thereon an etching stopper film and a phase shift film in this order, in which the phase shift film contains silicon and oxygen, in which the phase shift film has a refractive index nof 1.5 or more for light of 193 nm wavelength and an extinction coefficient kof 0.1 or less for light of 193 nm wavelength, in which the etching stopper film has a refractive index nof 2.6 or more for light of 193 nm wavelength and an extinction coefficient kof 0.4 or less for light of 193 nm wavelength, and the refractive index nand the extinction coefficient ksatisfy at least one of k≤[(−0.188×n)+0.879] and k≤[(2.75×n)−6.945].