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. 08, 2024
Filed:
May. 28, 2020
Toppan Inc., Tokyo, JP;
Ayumi Goda, Tokyo, JP;
Norihito Fukugami, Tokyo, JP;
TOPPAN INC., Tokyo, JP;
Abstract
There are provided a reflective photomask blank and a reflective photomask, which are compatibly capable of suppressing a shadowing effect and improving the life of a mask. A reflective photomask blank () includes a substrate (), a reflection part () provided on the substrate () and configured to reflect incident light, and a low reflection part () provided on the reflection part () and configured to absorb incident light. The low reflection part () has a multi layer structure of at least two layers or more layers. An outermost layer () of the low reflection part () has a refractive index n equal to or more than 0.90 and an extinction coefficient k equal to or less than 0.02 with respect to extreme ultraviolet (EUV) light (where a wavelength is 13.5 nm).