Pad conditioning disk gimbaling control

Abstract

Embodiments of the disclosure provided herein include a system and method for pad conditioning in chemical mechanical polishing. In an embodiment, a pad conditioning assembly includes a base, an arm coupled to the base, a conditioning head coupled to the arm, a gimbal control assembly including at least one electromagnet coupled to the conditioning head, a gimbal flexure configured to couple to a pad conditioning disk, and a gimbal control feature coupled to the gimbal flexure, and a controller configured to control operation of the pad conditioning assembly. In another embodiment, a method of conditioning a pad for chemical mechanical polishing includes initiating conditioning of a pad on a platen using a pad conditioning assembly, determining if a distance exceeds a predetermined threshold, and biasing a pad conditioning disk of the pad conditioning assembly.

What is claimed is: 
     
         1 . A pad conditioning assembly, comprising:
 a base;   an arm coupled to the base;   a conditioning head coupled to the arm;   a gimbal control assembly comprising:
 at least one electromagnet coupled to the conditioning head; 
 a gimbal flexure configured to couple to a pad conditioning disk; and 
 a gimbal control feature coupled to the gimbal flexure; and 
   a controller configured to control operation of the pad conditioning assembly.   
     
     
         2 . The pad conditioning assembly of  claim 1 , wherein the gimbal control feature is an annular feature lined with magnets configured to interact with the at least one electromagnet. 
     
     
         3 . The pad conditioning assembly of  claim 1 , wherein the gimbal control feature is a passive annular feature comprising a ferromagnetic material configured to interact with the at least one electromagnet. 
     
     
         4 . The pad conditioning assembly of  claim 1 , further comprising at least one sensor configured to provide a distance data stream. 
     
     
         5 . The pad conditioning assembly of  claim 1 , wherein the controller is configured to apply a bias to the gimbal control feature using the at least one electromagnet. 
     
     
         6 . The pad conditioning assembly of  claim 5 , wherein the bias is applied toward an outer edge of a platen. 
     
     
         7 . The pad conditioning assembly of  claim 5 , wherein the bias is applied toward a center of a platen. 
     
     
         8 . A gimbal control assembly, comprising:
 at least one electromagnet coupled to a conditioning head of a pad conditioner;   a gimbal flexure configured to couple to a pad conditioning disk of the pad conditioner; and   a gimbal control feature coupled to the gimbal flexure.   
     
     
         9 . The gimbal control assembly of  claim 8 , wherein the at least one electromagnet comprises a first electromagnet and a second electromagnet. 
     
     
         10 . The gimbal control assembly of  claim 9 , wherein the first electromagnet and the second electromagnet are aligned along a first axis that is parallel to a pad conditioning arm coupled to the conditioning head and configured to control a pitch of the pad conditioning disk. 
     
     
         11 . The gimbal control assembly of  claim 9 , wherein the first electromagnet and the second electromagnet are aligned along a second axis that is perpendicular to a pad conditioning arm coupled to the conditioning head. 
     
     
         12 . The gimbal control assembly of  claim 8 , wherein the at least one electromagnet comprises a first electromagnet, a second electromagnet, and a third electromagnet. 
     
     
         13 . The gimbal control assembly of  claim 12 , wherein the first electromagnet, the second electromagnet, and the third electromagnet are separated by a first angle, a second angle, and a third angle, a sum of the first angle, second angle, and third angle equal to 360 degrees. 
     
     
         14 . The gimbal control assembly of  claim 8 , wherein the at least one electromagnet comprises a first electromagnet, a second electromagnet, a third electromagnet, and a fourth electromagnet. 
     
     
         15 . A method of conditioning a pad for chemical mechanical polishing, comprising:
 initiating, using a controller, conditioning of a pad on a platen using a pad conditioning assembly;   receiving a distance data stream using at least one sensor of the pad conditioning assembly;   determining, using the controller, if the distance data stream exceeds a predetermined threshold; and   upon determining that the distance data stream exceeds the predetermined threshold, biasing a pad conditioning disk of the pad conditioning assembly.   
     
     
         16 . The method of  claim 15 , wherein biasing the pad conditioning disk comprises using at least one electromagnet to exert an electromagnetic force on a gimbal control feature disposed on the pad conditioning disk. 
     
     
         17 . The method of  claim 15 , wherein biasing the pad conditioning disk includes biasing an outside edge of the pad conditioning disk closest to an outside edge of the platen such that a cutting pressure is increased on the outside edge of the platen. 
     
     
         18 . The method of  claim 15 , wherein biasing the pad conditioning disk includes biasing an inner edge of the pad conditioning disk closest to a center of the platen such that a cutting pressure is increased on the center of the platen. 
     
     
         19 . The method of  claim 15 , wherein biasing the pad conditioning disk includes receiving input from a user interface of the controller. 
     
     
         20 . The method of  claim 15 , further comprising, after biasing the pad conditioning disk, further receiving the distance data stream using the at least one sensor.