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:
Dec. 27, 2005
Filed:
Jul. 06, 2004
Shinichi Nakabayshi, Hitachinaka, JP;
Hisahiko Abe, Tokyo, JP;
Hirofumi Tsuchiyama, Hitachinaka, JP;
Masaki Hiyama, Yokohama, JP;
Takashi Nishiguchi, Hitachinaka, JP;
Shinichi Nakabayshi, Hitachinaka, JP;
Hisahiko Abe, Tokyo, JP;
Hirofumi Tsuchiyama, Hitachinaka, JP;
Masaki Hiyama, Yokohama, JP;
Takashi Nishiguchi, Hitachinaka, JP;
Renesas Technology Corp., Tokyo, JP;
Abstract
In order to reduce micro scratches which tend to occur during chemical-mechanical polishing, a polishing slurry is diluted with deionized water immediately before it is supplied in a gap between a polishing pad and the surface of a wafer to be polished. By diluting the polishing slurry with deionized water to increase its volume, the concentration of coagulated particles contained in the polishing slurry can be lowered. For a mixture ratio of the polishing slurry and deionized water, about 1 (polishing slurry): 1–1.2 (deionized water) is used, and the concentration of silica contained in the diluted polishing slurry is adjusted to about 3–9 weight %, preferably about 4–8 weight %, and more preferably about 8 weight %.