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:
Apr. 29, 2025
Filed:
Jun. 22, 2021
Applicant:
Shin-etsu Chemical Co., Ltd., Tokyo, JP;
Inventor:
Kouhei Sasamoto, Joetsu, JP;
Assignee:
SHIN-ETSU CHEMICAL CO., LTD., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03F 1/32 (2011.12); H01L 21/033 (2005.12);
U.S. Cl.
CPC ...
H01L 21/0337 (2012.12); G03F 1/32 (2012.12); H01L 21/0332 (2012.12);
Abstract
A photomask is manufactured from a photomask blank including a transparent substrate, a first inorganic film which comprises silicon and is free of chromium, and a second inorganic film which comprises chromium and is free of silicon, and is in contact with the first inorganic film by a method including steps of forming a pattern of the second inorganic film by fluorine-based dry etching with using a resist pattern, and forming a pattern of the first inorganic film by fluorine-based dry etching with using the pattern of the second inorganic film.