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. 10, 1995
Filed:
Nov. 12, 1992
Dai Nippon Printing Co., Ltd., Tokyo, JP;
Abstract
The invention is directed to a phase shift photomask for which a film made of a material capable of providing an etching stopper layer that excels in etching selectivity and can interrupt etching surely and automatically, and provides a phase shift photomask at least comprising a substrate 30 and a phase shifter pattern made of a material composed mainly of silicon oxide that is provided on the surface of the substrate directly or with an opaque layer 37 interposed therebetween, said phase shift photomask being characterized in that the surface 30 is provided on the surface with an etching stopper layer 30 that comprises a mixture of Al.sub.2 O.sub.3 with MgO, ZrO.sub.2, Ta.sub.2 O.sub.5 or HfO, or CrO.sub.x, CrN.sub.y, CrC.sub.z, CrO.sub.x N.sub.y, CrO.sub.x C.sub.z or CrO.sub.x N.sub.y C.sub.z, or MgF.sub.2-2x O.sub.y, CaF.sub.2-2x O.sub.y, LiF.sub.2-2x O.sub.y, BaF.sub.2-2x O.sub.y, La.sub.2 F.sub.6-2x O.sub.y or Ce.sub.2 F.sub.6-2x O.sub.y, whereby the etching stopper layer is allowed to etch a transparent film for a phase shifter surely and accurately, when making a phase shifter pattern by etching.