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:
Jan. 07, 2020
Filed:
Sep. 10, 2018
Hoya Corporation, Tokyo, JP;
Osamu Nozawa, Tokyo, JP;
Ryo Ohkubo, Tokyo, JP;
Hiroaki Shishido, Tokyo, JP;
Yasushi Okubo, Tokyo, JP;
HOYA CORPORATION, Tokyo, JP;
Abstract
A mask blank is provided, by which an alignment mark can be formed between a transparent substrate and a laminated structure of a light semitransmissive film, etching stopper film, and light shielding film during manufacture of a transfer mask. The mask blankcomprises a structure in which the light semitransmissive film, etching stopper film, light shielding film, and etching mask filmare laminated in said order on the transparent substrate; the light semitransmissive filmand light shielding filmare made of a material which can be dry etched with a fluorine-based gas; the etching stopper film and etching mask film are made of a material containing chromium; and when a thickness of the etching stopper film is Ds, an etching rate of the etching stopper film with respect to an oxygen-containing chlorine-based gas is Vs, a thickness of the etching mask film is Dm, and an etching rate of the etching mask film with respect to the oxygen-containing chlorine-based gas is Vm, a relationship: (Dm/Vm)>(Ds/Vs) is satisfied.