Polishing system with three headed carousel

Abstract

Embodiments of the present invention provide a polishing module configured to use in a polishing system. The polishing module comprises a base member, two polishing stations disposed on the base member, one load cup, and a carousel having three polishing heads.

1 . A polishing module configured to use in a polishing system, comprising:
 a base member;   two polishing stations disposed on the base member, wherein each of the two polishing stations is configured to polish substrates;   a carousel supported by the base member, wherein the carousel comprises three substrate heads each configured to transfer a substrate and polish the substrate against the two polishing stations, and the carousel is configured to simultaneously rotate the three substrate heads about a carousel axis; and   a load cup disposed on the base member, wherein the load cup is configured to load substrates to the three substrates heads and to unload substrates from the three polishing heads, and the two polishing stations and the load cup are positioned to allow simultaneous alignment of each of the three substrate heads with one of the two polishing stations and the load cup.   
     
     
         2 . The polishing module of  claim 1 , wherein the three substrate heads are mounted on a carousel base at equal angular intervals about the carousel axis. 
     
     
         3 . The polishing module of  claim 1 , wherein each of the three substrate heads is independently operable. 
     
     
         4 . The polishing module of  claim 1 , wherein each of the three substrate heads has a radial movement relative to the carousel axis. 
     
     
         5 . The polishing module of  claim 4 , wherein the radial movement provides a sweeping motion during polishing. 
     
     
         6 . The polishing module of  claim 1 , wherein each of the two polishing stations comprises:
 a platen rotatable about a central axis;   a polishing pad disposed on the platen, wherein the polishing pad has a polishing surface configured to polishing the substrate;   a polishing solution dispenser configured to deliver polishing solution on to the polishing surface; and   a conditioner assembly configured to clean and maintain the polishing pad.   
     
     
         7 . A polishing system, comprising:
 a factory interface configured to receive unpolished substrates from substrate transferring cassettes and transfer polished substrates to the substrate transferring cassettes;   a substrate transferring platform configured to receive substrates from the factory interface;   a polishing assembly configured to polishing substrates in one or more polishing steps, wherein the polishing assembly comprises a first polishing module comprises:
 a first base member; 
 first and second polishing stations disposed on the first base member; 
 a first carousel supported by the first base member, wherein the first carousel comprises three substrate heads each configured to transfer a substrate and polish the substrate against the first and second polishing stations, and the first carousel is configured to simultaneously rotate the three substrate heads about a first carousel axis; and 
 a first load cup disposed on the first base member, wherein the first polishing station, the second polishing station and the first load cup are positioned to allow simultaneous alignment of each of the three substrate heads of the first carousel with one of the first polishing station, the second polishing station and the first load cup; 
   a polishing robot configured to transfer substrates from the substrate transferring platform to the polishing assembly; and   a cleaning assembly to clean polished the substrates.   
     
     
         8 . The polishing system of  claim 7 , wherein the polishing assembly further comprises a second polishing module disposed against the first polishing module. 
     
     
         9 . The polishing system of  claim 8 , wherein the second polishing module comprises:
 a second base member;   third and fourth polishing stations disposed on the second base member;   a second carousel supported by the second base member, wherein the second carousel comprises three substrate heads each configured to transfer a substrate and polish the substrate against the third and fourth polishing stations, and the second carousel is configured to simultaneously rotate the three substrate heads about a second carousel axis; and   a second load cup disposed on the second base member, wherein the third polishing station, the fourth polishing station and the second load cup are positioned to allow simultaneous alignment of each of the three substrate heads of the second carousel with one of the third polishing station, the fourth polishing station and the second load cup,   wherein the polishing robot is configured to transfer substrates between the first and second load cups.   
     
     
         10 . The polishing system of  claim 8 , wherein the second polishing module comprise:
 a second base member;   third and fourth polishing stations disposed on the second base member;   a second load cup disposed on the second base member;   a first polishing arm comprising a substrate head, and is configured to pivot the substrate head to align the substrate head with the third polishing station and the second load cup;   a second polishing arm comprising a substrate head, and is configured to pivot the substrate head to align the substrate head with the fourth polishing station and the second load cup, wherein the polishing robot is configured to transfer substrates between the first and second load cups   
     
     
         11 . The polishing system of  claim 7 , wherein the polishing robot is configured to transfer polished substrates to the cleaning assembly. 
     
     
         12 . The polishing system of  claim 11 , wherein the cleaning assembly comprises:
 a wet cleaning device;   a dry cleaning device; and   a cleaning robot configured to transfer substrates from the wet cleaning device to the dry cleaning device.   
     
     
         13 . The polishing system of  claim 12 , wherein the factory interface comprises an internal robot, and the internal robot is configured to transfer substrates from the dry cleaning device to the factory interface after a dry cleaning process. 
     
     
         14 . The polishing system of  claim 7 , wherein the substrate transferring platform comprises a substrate transferring belt configured to receive substrates from an internal robot of the factory interface, and the polishing robot is configured to pick substrates from the substrate transferring belt to the first load cup. 
     
     
         15 . The polishing system of  claim 7 , wherein the three substrate heads of the first polishing module are mounted on the first carousel base at equal angular intervals about the first carousel axis. 
     
     
         16 . A method for polishing a substrate, comprising:
 transferring a first substrate using a substrate transferring belt towards a polishing assembly;   transferring the first substrate from the substrate transferring belt to a first load cup of the polishing assembly;   loading the first substrate from the first load cup to a first substrate head mounted on a first carousel having three polishing heads;   aligning the first substrate head with a first polishing station of the polishing assembly;   polishing the first substrate in the first polishing station;   aligning the first substrate head with the first load cup; and   unloading the first substrate from the first substrate head to the first load cup.   
     
     
         17 . The method of  claim 15 , wherein aligning the first substrate head comprises:
 rotating the first carousel; and   moving the first substrate head radially.   
     
     
         18 . The method of  claim 15 , further comprising:
 upon finishing polishing the first substrate in the first polishing station, rotating the carousel;   moving the first substrate head radially to align with a second polishing station; and   polishing the first substrate in the second polishing station.   
     
     
         19 . The method of  claim 15 , further comprising:
 while aligning the first substrate head with the first polishing station of the polishing assembly, simultaneously loading a second substrate on a second substrate head of the first carousel by aligning the second substrate head with the first load cup;   aligning the first substrate head with a second polishing station of the polishing assembly and simultaneously aligning the second substrate head with the first polishing station; and   polishing the first substrate in the second polishing station and simultaneously polishing the second substrate in the second polishing station;   
     
     
         20 . The method of  claim 15 , further comprising:
 after unloading the first substrate to the first load cup, transferring the first substrate from the first load cup to a second load cup of the polishing assembly;   loading the first substrate to a third substrate head of a second carousel having three polishing heads;   aligning the third substrate head with a third polishing station by rotating the second carousel; and   polishing the first substrate at the third polishing station.