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. 14, 1998
Filed:
Feb. 27, 1996
Masakazu Muroyama, Kanagawa, JP;
Masayoshi Sasaki, Tokyo, JP;
Sony Corporation, Tokyo, JP;
Abstract
A polishing method and apparatus applied for planarizing a substrate presenting surface step differences in a production process for a substrate of a semiconductor device. The substrate is ground by being brought into sliding contact with a polishing cloth applied taut on a rotary table as a polishing agent is supplied to the polishing cloth. The grinding for the substrate is carried out until partway under a first condition in which the polishing cloth is ground under a pre-set condition by being slidingly contacted with grinding abrasive grains of the rotary grinding head so that surface roughness of the polishing cloth is maintained at a substantially constant value equal to the surface roughness value prevailing prior to start of grinding. The residual portion of the polishing is carried out under a second condition in which the surface roughness of the polishing cloth is gradually lowered by terminating the grinding. Polishing with superior planarity may be achieved in a shorter time.