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:
Nov. 13, 2012
Filed:
Jun. 10, 2010
Shinichi Igarashi, Joetsu, JP;
Yukio Inazuki, Joetsu, JP;
Hideo Kaneko, Joetsu, JP;
Hiroki Yoshikawa, Joetsu, JP;
Yoshinori Kinase, Joetsu, JP;
Shinichi Igarashi, Joetsu, JP;
Yukio Inazuki, Joetsu, JP;
Hideo Kaneko, Joetsu, JP;
Hiroki Yoshikawa, Joetsu, JP;
Yoshinori Kinase, Joetsu, JP;
Shin-Etsu Chemical Co., Ltd., Tokyo, JP;
Abstract
A photomask is manufactured from a photomask blank comprising a transparent substrate and a light-shielding film consisting of upper and lower layers of transition metal-containing silicon base materials, the content of O+N in the upper layer being higher than that of the lower layer. The light-shielding film is processed in two steps by fluorine dry etching through a resist pattern such that a lower portion of the film is left behind, and oxygen-containing chlorine dry etching for removing the remainder of the film.