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:
Feb. 14, 2012
Filed:
Sep. 08, 2006
Takeyuki Yamada, Tokyo, JP;
Atsushi Kominato, Tokyo, JP;
Hiroyuki Iwashita, Tokyo, JP;
Masahiro Hashimoto, Tokyo, JP;
Yasushi Okubo, Tokyo, JP;
Takeyuki Yamada, Tokyo, JP;
Atsushi Kominato, Tokyo, JP;
Hiroyuki Iwashita, Tokyo, JP;
Masahiro Hashimoto, Tokyo, JP;
Yasushi Okubo, Tokyo, JP;
Hoya Corporation, Tokyo, JP;
Abstract
There are provided a photomask blank which is capable of preventing static buildup caused by electron beam pattern drawing for forming a resist pattern, a photomask blank which provides a good pattern accuracy through optimization of the dry etching rate along the depth direction of the shielding film, and a photomask blank which is capable of reducing the dry etching time by increasing the dry etching rate of the shielding film. The photomask blank of the present invention includes a translucent substrate having thereon a shielding film composed mainly of chromium and the shielding film contains hydrogen. The shielding film is formed in such a manner that the film formation rate of the layer at the surface side is lower than the film formation rate of the layer at the translucent substrate side of the shielding film. The dry etching rate of the shielding film is lower at the translucent substrate side than at the surface side.