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. 20, 2015
Filed:
Oct. 09, 2012
Shin-etsu Chemical Co., Ltd., Chiyoda-ku, Tokyo, JP;
Shinichi Igarashi, Joetsu, JP;
Hideo Kaneko, Joetsu, JP;
Yukio Inazuki, Joetsu, JP;
Kazuhiro Nishikawa, Joetsu, JP;
SHIN-ETSU CHEMICAL CO., LTD., Tokyo, JP;
Abstract
A photomask is manufactured by providing a photomask blank comprising a transparent substrate, a phase shift film, and a light-shielding film, the phase shift film and the light-shielding film including silicon base material layers, a N+O content in the silicon base material layer of the phase shift film differing from that of the light-shielding film, and chlorine dry etching the blank with oxygen-containing chlorine gas in a selected O/Cl ratio for selectively etching away the silicon base material layer of the light-shielding film.