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:
Sep. 22, 2009
Filed:
Sep. 05, 2006
Yoshiaki Ikuta, Schenectady, NY (US);
Shinya Kikugawa, Chiyoda-ku, JP;
Yoshiaki Ikuta, Schenectady, NY (US);
Shinya Kikugawa, Chiyoda-ku, JP;
Asahi Glass Company, Limited, Tokyo, JP;
Abstract
For a substrate having fine convexoconcave patterns on its surface, the dimensions of the convexoconcave patterns in a vertical direction of a quartz glass substrate are controlled to be uniform with extreme accuracy and over the entire substrate surface. The quartz glass substrate is made to have a fictive temperature distribution of at most 40° C. and a halogen concentration of less than 400 ppm, and the etching rate of the surface of the quartz glass substrate is made uniform, whereby the dimensions of the convexoconcave patterns in a vertical direction of the quartz glass substrate are controlled to be uniform with good accuracy and over the entire substrate surface.