Method for polishing semiconductor wafers

Abstract

A method for polishing a plurality of semiconductor wafers includes providing a polishing pad containing an abrasive substance bonded in the polishing pad; providing an alkaline polishing agent at a volumetric flowrate greater than or equal to 5 liters/min.; polishing the plurality of semiconductor wafers using the polishing pad; and circulating the polishing agent in a polishing agent circuit during the polishing.

1 . A method for polishing a plurality of semiconductor wafers comprising:
 providing a polishing pad containing an abrasive substance bonded in the polishing pad;   providing an alkaline polishing agent at a volumetric flowrate greater than or equal to 5 liters/min.;   polishing the plurality of semiconductor wafers using the polishing pad; and   circulating the polishing agent in a polishing agent circuit during the polishing.   
     
     
         2 . The method as recited in  claim 1 , wherein the alkaline polishing agent is ultrapure water containing at least one of sodium carbonate, potassium carbonate, sodium hydroxide, potassium hydroxide, ammonium hydroxide and tetramethylammonium hydroxide. 
     
     
         3 . The method as recited in  claim 1 , wherein the alkaline polishing agent includes a slurry containing at least one abrasive selected from the group consisting of oxides of aluminum, cerium and silicon. 
     
     
         4 . The method as recited in  claim 2 , wherein the polishing agent has a pH value in a range of 10 to 12. 
     
     
         5 . The method as recited in  claim 1 , wherein the polishing agent includes colloidally dispersed silica and TMAH. 
     
     
         6 . The method as recited in  claim 1 , wherein the polishing pad includes at least one abrasive selected from the group consisting of particles of silicon carbide, boron nitride and diamond and of oxides of cerium, aluminum, silicon and zirconium, and wherein the particles have an average particle size greater than or equal to 0.1 μm and less than or equal to 1.0 μm. 
     
     
         7 . The method as recited in  claim 1 , wherein the circulating includes cooling the polishing agent during the circulating. 
     
     
         8 . The method as recited in  claim 1 , further comprising replenishing a defined amount or concentration of the polishing agent in a manner regulated according to a chemical consumption. 
     
     
         9 . The method as recited in  claim 1 , further comprising discharging a defined amount or concentration of used polishing agent and replacing the discharged used polishing agent with unused polishing agent. 
     
     
         10 . The method as recited in  claim 1 , further comprising collecting a first defined amount or concentration of used polishing agent in a holding container, reusing the first defined amount or concentration of the used polishing agent and replacing a second defined amount or concentration of the used polishing agent with a new polishing agent.