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:
Jan. 20, 2026
Filed:
Jul. 10, 2019
Ebara Corporation, Tokyo, JP;
Akira Nakamura, Tokyo, JP;
EBARA CORPORATION, Tokyo, JP;
Abstract
A film thickness measuring apparatus and an end point detector monitor a film thickness of a conductive film based on an output of an eddy current sensor disposed in a polishing table. The output of the eddy current sensor includes an impedance component, and when a resistance component and a reactance component of the impedance component are associated with the respective axes of a coordinate system having two orthogonal coordinate axes, at least some points on the coordinate system corresponding to the impedance component form at least a part of a circle. The film thickness measuring apparatus determines a distance between a point on the coordinate system and the center of the circle, determines the film thickness from the impedance component and corrects the determined film thickness using the determined distance.