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. 21, 2020
Filed:
Nov. 17, 2017
Ebara Corporation, Tokyo, JP;
Taro Takahashi, Tokyo, JP;
Akihiko Ogawa, Tokyo, JP;
EBARA CORPORATION, Tokyo, JP;
Abstract
A polishing apparatus of the present disclosure polishes a polishing target by pressing the polishing target against a polishing pad. An eddy current sensor measures an impedance that is changeable according to a change of a film thickness of the polishing target, at a plurality of positions of the polishing target, and outputs measurement signals. A difference calculator generates data corresponding to a film thickness based on a measurement signal. The difference calculator calculates a difference between data at different times based on measurement signals output by the eddy current sensor at different times at a center of the polishing target. An end point detector detects a polishing end point indicating the end of polishing based on the difference calculated by the difference calculator.