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:
Oct. 23, 2001
Filed:
Aug. 18, 2000
Applicant:
Inventors:
Chun-Hung Lu, Toliu, TW;
Mei-Yen Li, Tainan, TW;
Assignee:
Taiwan Semiconductor Manufacturing Company, Ltd, Hsin Chu, TW;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01B 1/106 ; G01N 2/155 ;
U.S. Cl.
CPC ...
G01B 1/106 ; G01N 2/155 ;
Abstract
End point detection during a CMP process on a semiconductor wafer employs confocal optics to increase signal-to-noise ratio near the end point. The use of confocal optics for sensing reflected light from the wafer surface exhibits greater selectivity where intermediate layers of metal are present in the wafer. A laser diode is used as a light source to examine the wafer surface. Light reflected back to the laser diode reduces its power state, and this power state is sensed by a current detector which outputs a signal representative of reflected light intensity.