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. 25, 2017
Filed:
Mar. 28, 2013
Ebara Corporation, Tokyo, JP;
Taro Takahashi, Tokyo, JP;
Mitsuo Tada, Tokyo, JP;
Ebara Corporation, Tokyo, JP;
Abstract
An eddy current sensor is used for detecting a metal film (or conductive film) formed on a surface of a substrate such as a semiconductor wafer. The eddy current sensor is disposed near the metal film or the conductive film formed on the substrate to detect an eddy current generated in the metal film or the conductive film. The eddy current sensor includes a plurality of coils having different sizes formed by winding a wire or a conductive material. The plurality of coils includes an inner coil and an outer coil spaced from each other, and the outer coil is configured to surround the inner coil. The plurality of coils are configured to detect respective eddy currents generated in the metal film or the conductive film.