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. 05, 2022
Filed:
Jun. 29, 2018
Toppan Printing Co., Ltd., Tokyo, JP;
Norihito Fukugami, Tokyo, JP;
Toru Komizo, Tokyo, JP;
TOPPAN PRINTING CO., LTD., Tokyo, JP;
Abstract
A reflective photomask blank () of a first aspect includes a substrate (); a reflective layer () formed on the substrate (); and a light absorbing layer () formed on the reflective layer (). The light absorbing layer () includes a tin oxide film with an atomic ratio (O/Sn) of oxygen (O) to tin (Sn) being more than 1.50 and equal to or less than 2.0, and with a film thickness of 25 nm or more and 45 nm or less. Consequently, the shadowing effect of a reflective photomask for pattern transfer using extreme ultraviolet light as a light source is suppressed or reduced to improve the performance of transfer to a semiconductor substrate, and further, the cleaning resistance of the light absorbing layer is improved.