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:
May. 09, 2023
Filed:
Sep. 10, 2020
Shin-etsu Chemical Co., Ltd., Tokyo, JP;
Takuro Kosaka, Joetsu, JP;
Keisuke Sakurai, Joetsu, JP;
SHIN-ETSU CHEMICAL CO., LTD., Tokyo, JP;
Abstract
A halftone phase shift-type photomask blank including a transparent substrate, and a halftone phase shift film formed on the substrate, and including at least one layer composed of silicon, nitrogen and oxygen is provided. The halftone phase shift film has a phase shift of at least 150° and up to 200° and a transmittance of at least 20%, with respect to exposure light having a wavelength of up to 200 nm, and a film surface having a surface roughness RMS of up to 0.8 nm, and an in-plane variation of transmittance calculated from the maximum transmittance Tand the minimum transmittance Twithin a mask pattern forming area by the expression: (T−T)/(T+T)×100 is up to 2%.