Polishing system and dressing device thereof

Abstract

Provided is a dressing device for a carrier. The dressing device comprises a dresser, a swing arm, a base and at least one damper. A first end and a second end of the swing arm are coupled to the dresser and the base, respectively, and the at least one damper is disposed inside the swing arm. Any axial vibration of the dresser or the swing arm during dressing for the carrier can be compensated or attenuated by the damper in an active manner properly, so as to make the surface of the carrier flatter and more uniform, which not only improves a removal rate of material and a polishing result of the surface in the subsequent chemical mechanical planarization process, but also prolongs the service life of the carrier. The present disclosure further relates to a polishing system for dressing the carrier by using the said dressing device.

What is claimed is: 
     
         1 . A dressing device, comprising:
 a dresser for dressing a surface of a carrier;   a swing arm having a first end and a second end opposed to the first end, wherein the first end is coupled to the dresser;   a base coupled to the second end and configured to make the swing arm and the dresser oscillate over the surface of the carrier; and   at least one damper disposed inside the swing arm to adjust vibration of the dresser or the swing arm during oscillation.   
     
     
         2 . The dressing device of  claim 1 , wherein the at least one damper is disposed adjacent to the first end. 
     
     
         3 . The dressing device of  claim 1 , wherein the at least one damper comprises a longitudinal axis damper for adjusting the vibration perpendicular to the surface of the carrier, a lateral axis damper for adjusting the vibration parallel to the surface of the carrier, or a combination thereof. 
     
     
         4 . The dressing device of  claim 1 , wherein the at least one damper comprises a tuned mass damper. 
     
     
         5 . The dressing device of  claim 4 , wherein the tuned mass damper is an active tuned mass damper. 
     
     
         6 . The dressing device of  claim 5 , wherein the active tuned mass damper comprises:
 a sensor for sensing a real-time motion signal corresponding to the vibration;   a control unit configured to calculate a load of the vibration according to the real-time motion signal and generate a control signal according to the load; and   an actuator configured to adjust a damping coefficient of the active tuned mass damper according to the control signal, thereby making the active tuned mass damper outputs an active control force of the load to reduce the vibration.   
     
     
         7 . The dressing device of  claim 6 , wherein the sensor is a piezoelectric sensor, the real-time motion signal is a real-time accelerating signal, the control unit is a control circuit, the actuator is a piezoelectric actuator, and the piezoelectric actuator is configured to output the active control force through a damping frequency for reducing the vibration. 
     
     
         8 . The dressing device of  claim 1 , wherein the base comprises a rotating shaft rotated by an actuator to drive the swinging arm and the dresser to oscillate over the carrier. 
     
     
         9 . A polishing system comprising:
 a rotatable platform;   a carrier disposed on an upper surface of the rotatable platform to carry a wafer or a substrate;   a holder disposed over the carrier to retain the wafer on a surface of the carrier to process polishing;   a dressing device of  claim 1 , which is disposed over the carrier to dress the surface of the carrier.   
     
     
         10 . The polishing system of  claim 9 , further comprising:
 a nozzle disposed over the carrier to supply a slurry including abrasives to the surface of the carrier.