Method to improve control in CMP processing

Abstract

A method and apparatus for adding slurry using a moveable outlet, such as one or more moveable arms, in a semiconductor wafer polishing system. The end of the slurry arm could be set to fan out the slurry as the slurry is dispensed onto the pad. Preferably, the arm is set so that the distance and centering of the arm is controlled by the setup of the process. The arm could be set to move in an arc, or to move in and out on a set track. Regardless, the slurry is preferably sprayed onto the pad in the location needed to place the slurry on the pad, but only in the areas that are needed. This increases the control of the uniformity of the process, and preferably reduces the total amount of slurry that is used in the process.

1 . A method of wetting a semiconductor wafer, said method comprising: using a wafer carrier to hold the wafer to a polishing pad; dispensing a chemical through at least one outlet to the polishing pad; and moving the at least one outlet while dispensing the chemical.  
   
   
       2 . A method as recited in  claim 1 , wherein the step of dispensing a chemical comprises dispensing a slurry.  
   
   
       3 . A method as recited in  claim 1 , wherein the step of moving the at least one outlet comprises moving the outlet in an arc motion.  
   
   
       4 . A method as recited in  claim 1 , wherein the step of moving the at least one outlet comprises moving the outlet in a back and forth motion.  
   
   
       5 . A method as recited in  claim 1 , wherein the polishing pad is disposed on a polishing table and said method further comprises rotating at least one of the wafer carrier and the polishing table.  
   
   
       6 . A method as recited in  claim 1 , wherein the step of dispensing a chemical through at least one outlet comprises dispensing a chemical through a plurality of outlets to the polishing pad; and moving the outlets while dispensing the chemical.  
   
   
       7 . A method as recited in  claim 1 , further comprising providing at least one moveable arm which carries said at least one outlet.  
   
   
       8 . A method as recited in  claim 7 , further comprising moving said at least one moveable arm while dispensing the chemical.  
   
   
       9 . A method as recited in  claim 8 , further comprising moving the at least one moveable arm in an arc motion.  
   
   
       10 . A method as recited in  claim 8 , further comprising moving the at least one moveable arm in a back and forth motion.  
   
   
       11 . A machine for polishing a semiconductor wafer, said machine comprising: a polishing pad; a wafer carrier configured to hold the semiconductor wafer to the polishing pad; and at least one moveable outlet configured to dispense a chemical to the polishing pad.  
   
   
       12 . A machine as recited in  claim 11 , wherein the moveable outlet is configured to move in an arc motion.  
   
   
       13 . A machine as recited in  claim 11 , wherein the moveable outlet is configured to move in a back and forth motion.  
   
   
       14 . A machine as recited in  claim 11 , wherein the polishing pad is disposed on a polishing table and at least one of the wafer carrier and the polishing table is rotatable.  
   
   
       15 . A machine as recited in  claim 11 , wherein the at least one moveable outlet comprises a plurality of outlets.  
   
   
       16 . A machine as recited in  claim 11 , further comprising at least one moveable arm which carries said at least one outlet.  
   
   
       17 . A machine as recited in  claim 16 , wherein the at least one moveable arm is configured to move in an arc motion.  
   
   
       18 . A machine as recited in  claim 16 , wherein the at least one moveable arm is configured to move in a back and forth motion.