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:
Sep. 22, 2020
Filed:
Jan. 30, 2018
Applicant:
Shin-etsu Chemical Co., Ltd., Tokyo, JP;
Inventors:
Assignee:
SHIN-ETSU CHEMICAL CO., LTD., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03F 1/22 (2012.01); G03F 1/32 (2012.01); C01B 33/06 (2006.01); C01B 21/082 (2006.01); C22C 27/06 (2006.01); C23C 14/14 (2006.01); C23C 14/34 (2006.01); G03F 1/84 (2012.01); G03F 1/54 (2012.01);
U.S. Cl.
CPC ...
G03F 1/32 (2013.01); C01B 21/0821 (2013.01); C01B 21/0823 (2013.01); C01B 33/06 (2013.01); C22C 27/06 (2013.01); C23C 14/14 (2013.01); C23C 14/3414 (2013.01); G03F 1/54 (2013.01); G03F 1/84 (2013.01);
Abstract
A method for preparing a photomask blank comprising a transparent substrate and a chromium-containing film contiguous thereto involves the step of depositing the chromium-containing film by sputtering a metallic chromium target having an Ag content of up to 1 ppm. When a photomask prepared from the photomask blank is repeatedly used in patternwise exposure to ArF excimer laser radiation, the number of defects formed on the photomask is minimized.