Adhesive bonding and miscellaneous chemical manufacture – Differential fluid etching apparatus – With microwave gas energizing means
Reexamination Certificate
1999-04-07
2001-09-18
Utech, Benjamin L. (Department: 1765)
Adhesive bonding and miscellaneous chemical manufacture
Differential fluid etching apparatus
With microwave gas energizing means
Reexamination Certificate
active
06290808
ABSTRACT:
TECHNICAL FIELD OF THE INVENTION
This invention relates generally to the field of semiconductor device fabrication and more particularly to a chemical mechanical polishing machine with ultrasonic vibration and method.
BACKGROUND OF THE INVENTION
Chemical mechanical polishing typically involves mounting a semiconductor wafer on a wafer holder. The wafer holder presses the wafer against an abrasive polishing surface which is moving with respect to the wafer. A chemical slurry is inserted between the wafer and the polishing surface. The chemical slurry includes abrasive particles which mechanically polish the wafer, as well as etchants which chemically remove material from the pad of the wafer. Typically, the wafer holder rotates the wafer as the wafer moves with respect to the polishing surface. This added motion increases the uniformity with which the wafer is polished. However, over time, the polishing surface may absorb the chemical slurry. This may change the properties of the abrasive surface over time.
SUMMARY OF THE INVENTION
Therefore, a need has arisen for an improved chemical mechanical polishing machine that addresses the disadvantages and deficiencies of the prior art.
A chemical mechanical polishing machine with ultrasonic vibration is disclosed. In one embodiment, the chemical mechanical polishing machine includes a movable abrasive surface. A wafer holder holds a wafer in contact with the abrasive surface, and a vibration generator vibrates the wafer during polishing. In another embodiment, the vibration generator vibrates the abrasive surface during polishing of the wafer.
A technical advantage of the present invention is that the ultrasonic vibration agitates the slurry, thereby preventing the abrasive particles suspended in the chemical slurry from settling into the abrasive surface. Another technical advantage is that the ultrasonic vibration provides an additional degree of motion between the wafer and the abrasive surface, thus increasing the uniformity with which the wafer is polished. Yet another technical advantage is that the ultrasonic vibration also increases the exchange of slurry underneath the wafer with fresh slurry surrounding the wafers.
REFERENCES:
patent: 4879258 (1989-11-01), Fisher
patent: 5522965 (1996-06-01), Chisholm et al.
patent: 5531861 (1996-07-01), Yu et al.
patent: 5688364 (1997-11-01), Sato
patent: 5895550 (1999-04-01), Andreas
patent: 5897425 (1999-04-01), Fisher, Jr. et al.
patent: 5961372 (1999-10-01), Shendon
patent: 6000997 (1999-12-01), Kao et al.
Cho Chih-Chen
Hwang Ming J.
McKee Jeffrey A.
Brady III W. James
Telecky , Jr. Frederick J.
Texas Instruments Incorporated
Tran Binh X.
Utech Benjamin L.
LandOfFree
Chemical mechanical polishing machine with ultrasonic... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Chemical mechanical polishing machine with ultrasonic..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Chemical mechanical polishing machine with ultrasonic... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2545686