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:
Mar. 09, 2021
Filed:
Oct. 08, 2019
Hoya Corporation, Tokyo, JP;
HOYA CORPORATION, Tokyo, JP;
Abstract
A mask blank having a phase shift film and a light shielding film laminated on a transparent substrate. The phase shift film transmits ArF exposure light at a transmittance of from 2% to 30% and generates a phase difference of from 150° to 200°, is formed from a material containing Si and not substantially containing Cr, and has a lower layer (L) and an upper layer (U) laminated from the transparent substrate side. A refractive index n for layer L is below that of the substrate while n for layer U is higher, and layer L has an extinction coefficient k higher than that of layer U. The light shielding film includes a layer in contact with the phase shift film that is formed from a material containing Cr, has a n lower than that of layer U, and has an extinction coefficient k higher than that of layer U.