Modular chemical mechanical polisher with simultaneous polishing and pad treatment

Abstract

The present disclosure is directed towards polishing modules for performing chemical mechanical polishing of a substrate. The substrate may be a semiconductor substrate. The polishing modules described have a plurality of pads, such as polishing pads, disposed within a single polishing station. The pads are configured to remain stationary during processing, such as during polishing or buff operations. Either an x-y gantry assembly or a head actuation assembly is coupled to a system body of a polishing module and is configured to move a carrier head over the pads. Between process operations the polishing pads may be indexed to expose a new polishing pad to the carrier head.

What is claimed is: 
     
         1 . A substrate polishing system, configured for use during semiconductor manufacturing, comprising:
 a system body that includes one or more walls that define a processing region;   a first platen disposed in the processing region of the system body;   a second platen disposed in the processing region of the system body;   a central rail support disposed between the first platen and the second platen and within the processing region of the system body;   a first head assembly disposed above one of the first platen or the second platen comprising:
 a first carrier head; and 
 a first support arm coupling the first carrier head to the central rail support; and 
   a second head assembly disposed above one of the first platen or the second platen comprising:
 a second carrier head; and 
 a second support arm coupling the second carrier head to the central rail support. 
   
     
     
         2 . The substrate polishing system of  claim 1 , wherein the first head assembly further comprises a first rotation shaft disposed on an inner end of the first support arm opposite the first carrier head and the second head assembly further comprises a second rotation shaft disposed through an inner end of the second support arm opposite the second carrier head. 
     
     
         3 . The substrate polishing system of  claim 1 , wherein at least one pad drive unit is configured to index one or more polishing pads disposed on the first platen and the second platen. 
     
     
         4 . The substrate polishing system of  claim 3 , wherein the first platen is configured to have a first pad coupled to a first side facing the first carrier head and a second pad coupled to a second side facing away from the first carrier head while the second platen is configured to have a third pad coupled to a third side facing the second carrier head and a second pad coupled to a fourth side facing away from the second carrier head. 
     
     
         5 . The substrate polishing system of  claim 1 , further comprising:
 a first pad wash station and a second pad wash station disposed on an opposite side of the first platen from either of the first head assembly or the second head assembly.   
     
     
         6 . The substrate polishing system of  claim 5 , wherein the first pad wash station further comprises a first pad conditioner and the second pad wash station further comprises a second pad conditioner. 
     
     
         7 . The substrate polishing system of  claim 1 , wherein the central rail support comprises a first rail on a first side and a second rail on a second side, such that the first head assembly is coupled to the first rail while the second head assembly is coupled to the second rail. 
     
     
         8 . The substrate polishing system of  claim 1 , wherein the central rail support is coupled to a wall of the system body and further comprises:
 a linear actuator; and   a central rotation shaft coupled to the linear actuator having a central rotation axis, wherein both of the first head assembly and the second head assembly are coupled to the central rotation shaft.   
     
     
         9 . The substrate polishing system of  claim 1 , further comprising one or more liquid delivery units configured to supply one or more of a slurry, a conditioning fluid, or water. 
     
     
         10 . A substrate polishing station, comprising:
 a system body that includes one or more walls that define a processing region;   a platen disposed within the processing region of the system body having a rectangular pad supporting surface that is configured to receive a non-axisymmetric polishing pad, wherein a long side of the rectangular pad supporting surface is aligned in a first direction; and   a head assembly disposed over the pad supporting surface of the platen, wherein the head assembly comprises:
 a carrier head disposed over the pad supporting surface of the platen; 
 a linear actuator connected to a central rail support; and 
 a support arm that couples the carrier head to the linear actuator, wherein the linear actuator is configured to position the carrier head and support arm in the first direction. 
   
     
     
         11 . The substrate polishing station of  claim 10 , wherein the platen has a length and a width with an aspect ratio of greater than about 2:1. 
     
     
         12 . The substrate polishing station of  claim 10 , further comprising:
 a pad drive unit configured to index a first non-axisymmetric polishing pad disposed on a first side of the platen to a second side of the first platen opposite the first side; and   a pad washing module, which comprises one or more fluid nozzles, is disposed on the second side of the platen.   
     
     
         13 . The substrate polishing station of  claim 12 , wherein a pad conditioner is disposed on the second side of the platen. 
     
     
         14 . The substrate polishing station of  claim 10 , further comprising:
 a pad conditioner disposed on a conditioning side of the platen that is opposite to a polishing side of the platen, wherein the polishing side of the platen includes the rectangular pad supporting surface;   a linear conditioner actuator; and   a connecting arm that is coupled between the linear conditioner actuator and the pad conditioner, wherein the linear conditioner actuator is configured to position the pad conditioner and connecting arm in the first direction.   
     
     
         15 . The substrate polishing station of  claim 10 , wherein the linear actuator is the only means to generate relative motion between the carrier head and a non-axisymmetric polishing pad disposed on the rectangular pad supporting surface. 
     
     
         16 . The substrate polishing station of  claim 10 , further comprising a height of less than about 1000 mm and a width of less than about 2500 mm. 
     
     
         17 . A substrate polishing system, configured for use during semiconductor manufacturing, comprising:
 a system body that includes one or more walls that define a processing region;   a first platen disposed in the processing region of the system body;   a second platen disposed in the processing region of the system body;   a central rail support disposed between the first platen and the second platen and within the processing region of the system body;   a first head assembly disposed above the first platen comprising:
 a first carrier head; and 
 a first support arm coupling the first carrier head to the central rail support; and 
   a gantry disposed in the processing region and coupled to the first head assembly.   
     
     
         18 . The substrate polishing system of  claim 17 , wherein the gantry is disposed over the first platen and the second platen, the gantry comprising:
 a first cross bar coupled to the first head assembly; and   a second cross bar coupled to a pad conditioner.   
     
     
         19 . The substrate polishing system of  claim 17 , wherein the gantry is disposed over the first platen and the second platen, the gantry comprising:
 a first cross bar coupled to the first head assembly; and   a second cross bar coupled to a second carrier head disposed over the second platen.   
     
     
         20 . The substrate polishing system of  claim 17 , further comprising:
 a first non-axisymmetric polishing pad disposed on the first platen; and   a second non-axisymmetric polishing pad disposed on the second platen.