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:
May. 23, 2023
Filed:
Aug. 25, 2020
Ebara Corporation, Tokyo, JP;
Tomoko Owada, Tokyo, JP;
Osamu Nabeya, Tokyo, JP;
Yuta Suzuki, Tokyo, JP;
Shingo Togashi, Tokyo, JP;
EBARA CORPORATION, Tokyo, JP;
Abstract
A method of detecting abnormality of a roller which transmits a local load to a retainer ring is disclosed. The method comprises: rotating a polishing head which includes a head body and a retainer ring, the head body having a pressing surface for pressing a substrate, the retainer ring being arranged so as to surround the pressing surface; measuring a torque for rotating the polishing head, while rotating a rotary ring together with the polishing head and while exerting a local load to a stationary ring located on the rotary ring, the rotary ring being fixed to the retainer ring and having a plurality of rollers; generating a torque waveform indicating relationship between measured values of the torque for rotating the polishing head and measuring times of the torque; performing Fourier-transform process on the torque waveform to determine an intensity of frequency component of the torque waveform; and determining that at least one of the rollers malfunctions when the determined intensity of the frequency component is larger than a predetermined threshold value.