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:
Jul. 16, 2002
Filed:
Dec. 30, 1997
Applicant:
Inventors:
Jun Matsuzawa, Tsukuba, JP;
Yasushi Kurata, Tsukuba, JP;
Kiyohito Tanno, Hitachi, JP;
Yoshio Honma, Tokyo, JP;
Assignee:
Hitachi Chemical Company, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L 2/1302 ; H01L 2/1461 ;
U.S. Cl.
CPC ...
H01L 2/1302 ; H01L 2/1461 ;
Abstract
The invention relates to an abrasive containing a slurry of the cerium oxide grains dispersed in water. The Cerium oxide grains are obtained by adding hydrogen peroxide to an aqueous dispersion of cerium carbonate. The Cerium oxide grains are obtained by oxidizing a precipitate, which is formed through addition of ammonium hydrogencarbonate to an aqueous solution of cerium nitrate, with hydrogen peroxide. The Cerium oxide grains are obtained by neutralizing or alkallfying an aqueous solution of cerium ammonium nitrate.