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:
Aug. 16, 2005
Filed:
Dec. 27, 2001
Masaki Takeuchi, Nakakubiki-gun, JP;
Atsushi Watabe, Nakakubiki-gun, JP;
Tetsushi Tsukamoto, Nakakubiki-gun, JP;
Yukio Shibano, Nakakubiki-gun, JP;
Masaki Takeuchi, Nakakubiki-gun, JP;
Atsushi Watabe, Nakakubiki-gun, JP;
Tetsushi Tsukamoto, Nakakubiki-gun, JP;
Yukio Shibano, Nakakubiki-gun, JP;
Shin-Etsu Chemical Co., Ltd., Tokyo, JP;
Abstract
A silica glass substrate is obtained by polishing, cleaning, drying and etching a silica glass substrate slice. When the substrate on one surface is treated with a reactive reagent, defects having a size of at least 0.3 μm in a direction parallel to the substrate major surface are absent on the substrate surface. The silica glass substrate, in which no submicron defects manifest on the substrate surface even when treated as by cleaning or etching, serves as a reticle for use in photolithographic IC fabrication, achieving an improved manufacturing yield in the semiconductor device fabrication and microelectronic system fields.