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:
Apr. 04, 2000
Filed:
May. 14, 1998
Kenji Doi, Kawasaki, JP;
Naoto Miyashita, Yokohama, JP;
Masahiro Abe, Yokohama, JP;
Hiroyuki Kohno, Tokuyama, JP;
Hiroshi Kato, Tokuyama, JP;
Kazuhiko Hayashi, Tokuyama, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Tokuyama Corporation, Tokuyama, JP;
Abstract
An abrasive material is prepared by dispersing silicon nitride particles acting as abrasive particles in a solvent such as a pure water or an ultra pure water, followed by adding an adsorptive stickable to the abrasive particles to the dispersion. The resultant abrasive material permits diminishing the polishing rate of a silicon nitride film used as a stopper film, with the result that a CVD SiO.sub.2 film to be polished is selectively polished relative to the Si.sub.3 N.sub.4 film used as the stopper film. This makes it possible to make the stopper film as thin as possible and permits the CVD SiO.sub.2 film to be flattened efficiently without bringing about a dishing problem.