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:
Mar. 08, 2011
Filed:
Sep. 29, 2006
Takeyuki Yamada, Tokyo, JP;
Yasushi Okubo, Tokyo, JP;
Masao Ushida, Tokyo, JP;
Hiroyuki Iwashita, Tokyo, JP;
Takeyuki Yamada, Tokyo, JP;
Yasushi Okubo, Tokyo, JP;
Masao Ushida, Tokyo, JP;
Hiroyuki Iwashita, Tokyo, JP;
Hoya Corporation, Tokyo, JP;
Abstract
It is provided a photomask blank that has good flatness when a light-shielding film is patterned and hence can provide a good mask pattern accuracy and a good pattern transfer accuracy, and a method of producing a photomask. A photomask blank of the present invention includes a light-shielding film containing at least chromium on a light-transmitting substrate. The light-shielding film is formed so as to cause a desired film stress in the direction opposite to that of a change in the film stress that is anticipated to be caused in the light-shielding film by heat treatment according to a resist film formed on the light-shielding film. A photomask is produced by patterning the light-shielding film of the photomask blank by dry etching.