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:
May. 15, 2007
Filed:
Feb. 23, 2005
Applicants:
Masaru Mitsui, Tokyo, JP;
Haruhiko Yamagata, Tokyo, JP;
Masao Ushida, Tokyo, JP;
Inventors:
Assignee:
Hoya Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03F 7/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
In obtaining a photomask blankby disposing a sputtering target in a vacuum chamber and forming thin filmsandwith a three-layer construction of CrN/CrC/CrON over a transparent substrateby reactive sputtering, the thin films are formed in a mixed gas atmosphere containing helium, and the helium gas flux in the mixed gas is controlled such that the crystal grain diameter of the CrC thin film, which is the thickest film, will be 3 to 7 nm. This yields a photomask blank having thin films with low film stress, having good film quality, and which can be produced at a high yield in mass production.