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:
Jul. 19, 2011
Filed:
May. 16, 2006
Takehiko Ueda, Yokohama, JP;
Hosei Nakahira, Tokyo, JP;
Akira Ishikawa, Kawasaki, JP;
Nikon Corporation, Tokyo, JP;
Abstract
The spectral reflectance spectrum of an object of polishing that has reached the polishing endpoint is found ahead of time, the spectral reflectance spectrum of the object of polishing is found during polishing, and the correlation coefficient of these is seen as parameter 1. Meanwhile, the sum of the absolute values of the difference between the first order differentials of these is seen as parameter 2. Then, when parameter 1 is in a range exceeding a specific value, and parameter 2 is at its minimum, it is concluded that the polishing endpoint has been reached. Thus, it is possible to provide a method for detecting the polishing endpoint in a highly reliable CMP polishing apparatus.