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:
Nov. 15, 2016
Filed:
Jun. 25, 2013
Hoya Corporation, Tokyo, JP;
Yasushi Okubo, Tokyo, JP;
Ryo Ohkubo, Tokyo, JP;
HOYA CORPORATION, Tokyo, JP;
Abstract
A mask blank suitable for fabricating a phase shift mask having a thin film pattern composed of a material enabling dry etching with a fluorine-based gas and a substrate-engraved pattern. The mask blankis used to fabricate a phase shift mask having a thin film pattern and a substrate-engraved pattern. The mask blankhas a structure in which an etching stopper film, a thin film for pattern formationand an etching mask filmare laminated in this order on a transparent substrate. The etching stopper filmis made of a material that contains chromium and oxygen and the oxygen content thereof is more than 50 at %. The thin filmis made of a material that can be dry-etched by a fluorine-based gas. The etching mask filmis made of a material that contains chromium, the chromium content thereof is not less than 45 at %, and the oxygen content thereof is not more than 30 at %.