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:
Nov. 28, 2000
Filed:
Oct. 30, 1998
Ming-Cheng Yang, Taipei, TW;
Feng-Yeu Shau, Tainan Hsien, TW;
Cheng-Sung Huang, Feng-Yuan, TW;
Champion Yi, Hsinchu Hsien, TW;
United Microelectronics Corp., Hsinchu, TW;
Abstract
A method of monitoring the state of chemical-mechanical polishing that can be applied to the polishing of a metallic layer over a substrate. The method includes performing a series of scanning operations while a wafer is being polished to generate multiple reflectance line spectra in each polishing period. The degree of dispersion of the reflectance spectra is then utilized as a polishing index. In this invention, the standard deviation of the reflectance spectra in each period is used as a monitoring index, and the peak value of the standard deviation is used to determine the polishing end point. Surface uniformity is monitored by using the time interval between two time nodes at half the peak standard deviation values. When the distance of separation between the two time nodes is large, it means that the polished surface is not sufficiently flat.