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:
Oct. 01, 1996
Filed:
Jul. 19, 1994
Applicant:
Inventors:
Hiroshi Mohri, Tokyo, JP;
Masahiro Takahashi, Tokyo, JP;
Jiro Takei, Tokyo, JP;
Sachiko Ishikita, Tokyo, JP;
Hiroyuki Miyashita, Tokyo, JP;
Assignee:
DAI Nippon Printing Co., Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03F / ;
U.S. Cl.
CPC ...
430-5 ; 430271 ; 430321 ; 428209 ; 428210 ;
Abstract
The invention provides a phase shift photomask which includes an etching stopper layer transparent to ultraviolet illumination light and well resistant to etching as well as chemicals, acids, etc., and enables a phase shift angle to be controlled with high accuracy. In a phase shift photomask including a transparent substrate 210, and an etching stopper layer 202 and at least a phase shifter pattern 204 stacked on the substrate in this order, the etching stopper layer 202 is composed predominantly of hafnium oxide.