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, 2004
Filed:
Aug. 27, 2001
Akira Ishikawa, Kawasaki, JP;
Yoshijiro Ushio, Yokohama, JP;
Nikon Corporation, Tokyo, JP;
Abstract
Prior to the polishing of the wafer, a reflective body which has the same shape and dimensions as the wafer is held on the polishing head instead of the wafer. A polishing agent is interposed between the window of the polishing head and the reflective body, and the reflective body is pressed against the polishing pad with the same pressure as that applied during the polishing of the wafer. In this state, the reflective body is irradiated via the window with a probe light emitted from the light source, and the spectroscopic intensity of the reflected light is obtained from the sensor as a reference spectrum. During the polishing of the wafer, the spectroscopic intensity of the reflected light from the wafer is successively obtained as measured spectra from sensor; the intensity ratio of these measured spectra to the above-mentioned reference spectrum is determined, and the polishing state of the wafer is monitored on the basis of this intensity ratio.