Flexure mounted pad for chemical mechanical polishing

Abstract

A chemical mechanical polishing system includes a chuck assembly with a chuck for holding a substrate, a motor to rotate the chuck about a first axis, and a pad carrier assembly. The pad carrier assembly includes a movable support, a lateral actuator coupled the support to move the support along the radial direction, a flexure having a first end secured to the support and a second end, a pad carrier/attachment secured to a bottom side of the second end of the flexure for receiving and holding a polishing pad, a support arm extending from the support over the flexure such that the support arm and the flexure move together along the radial direction with the second end of the flexure vertically movable relative to the support arm, and a pad carrier actuator secured to the arm to apply a downward pressure to a top of the flexure.

1 . A chemical mechanical polishing system, comprising:
 a chuck assembly comprising a chuck configured to hold a substrate during a polishing operation;   a motor configured to rotate the chuck about a first axis; and   a pad carrier assembly including a support that is movable along a radial direction relative to the first axis, a lateral actuator coupled to the support and configured to cause the support to move along the radial direction, a flexure having a first end secured to the support and a second end, a pad carrier/attachment secured to a bottom side of the second end of the flexure and configured to receive and hold a polishing pad, a support arm extending from the support over the flexure such that the support arm and the flexure move together along the radial direction with the second end of the flexure vertically movable relative to the support arm, and a pad carrier actuator secured to the arm and configured to apply a downward pressure to a top of the flexure.   
     
     
         2 . The system of  claim 1 , wherein the pad carrier actuator comprises a membrane secured to a bottom of the arm to form a pressurizable chamber. 
     
     
         3 . The system of  claim 2 , wherein an outer surface of the membrane directly contacts the top surface of the flexure when the chamber is sufficiently pressurized. 
     
     
         4 . The system of  claim 1 , comprising a controller configured to cause the lateral actuator to radially oscillate the pad carrier and polishing pad during polishing of the substrate by the polishing pad. 
     
     
         5 . The system of  claim 1 , comprising a conditioner ring positioned concentrically with the chuck, wherein the support has a sweep range along the radial direction from a first position in which the polishing pad attached to the pad carrier is positioned over the chuck for polishing of the substrate and a second position in which the polishing pad is positioned over the conditioner ring for conditioning of the polishing pad. 
     
     
         6 . The system of  claim 5 , wherein the conditioner ring is rotatable about the first axis. 
     
     
         7 . The system of  claim 5 , comprising a vertical actuator configured to move the chuck vertically through an aperture in the conditioner ring. 
     
     
         8 . The system of  claim 7 , comprising a vertical actuator configured to move the chuck vertically between a raised position in which the substrate is positioned to contact the polishing pad and a lowered position in which the substrate is below the conditioner ring. 
     
     
         9 . The system of  claim 5 , comprising a controller configured to cause the lateral actuator to move the pad carrier and polishing pad from the first position to the second position after completion of polishing of the substrate. 
     
     
         10 . The system of  claim 9 , wherein the controller is configured to cause the lateral actuator to radially oscillate the pad carrier and polishing pad during polishing of the substrate by the polishing pad. 
     
     
         11 . The system of  claim 1 , comprising a substrate robot transfer robot configured to transfer the substrate into or out of the system. 
     
     
         12 . The system of  claim 11 , comprising a vertical actuator configured to move the chuck vertically between a raised position in which the substrate is positioned to contact the polishing pad and a lowered position in which the substrate is accessible to the substrate transfer robot. 
     
     
         13 . The system of  claim 12 , wherein the chuck comprises lift pins configured to rise out of and recede back into the chuck to transfer substrate to the substrate transfer robot. 
     
     
         14 . The system of  claim 1 , comprising the polishing pad, and wherein the polishing pad is an arcuate polishing pad. 
     
     
         15 . A chemical mechanical polishing system, comprising:
 a chuck assembly comprising a chuck configured to hold a substrate during a polishing operation;   a motor configured to rotate the chuck about a first axis; and   a plurality of pad carrier assemblies arranged around the first axis, wherein each pad carrier assembly of the plurality pad carrier assemblies includes a support that is movable along a radial direction relative to the first axis, a lateral actuator coupled the support to cause the support to move along the radial direction, a pad carrier/attachment supported from the support and configured to receive and hold a polishing pad, and a pad carrier actuator configured to apply a downward pressure to the pad carrier.   
     
     
         16 . The system of  claim 15 , wherein the plurality of pad carrier assemblies are arranged at equal angular intervals around the first axis. 
     
     
         17 . The system of  claim 16 , wherein the plurality of pad carrier assemblies has exactly four pad carrier assemblies. 
     
     
         18 . The system of  claim 15 , comprising the polishing pad, and wherein the polishing pad is an arcuate polishing pad. 
     
     
         19 . The system of  claim 15 , comprising a controller configured to cause the lateral actuators of the plurality of pad carrier assemblies at the same radial distance from the first axis during polishing of the substrate. 
     
     
         20 . The system of  claim 15 , comprising a controller configured to cause the lateral actuators of the plurality of pad carrier assemblies to radially oscillate the pad carriers and polishing pads in synchronization during polishing of the substrate. 
     
     
         21 . The system of  claim 15 , wherein each pad carrier assembly includes a flexure having a first end secured to the support and a second end, and a support arm extending from the support over the flexure such that the support arm and the flexure move together along the radial direction with the second end of the flexure vertically movable relative to the support arm, and
 wherein the pad carrier/attachment is secured to a bottom side of the second end of the flexure, and the pad carrier actuator is secured to the arm to apply a downward pressure to a top of the flexure.