Planarization composition

Abstract

The present invention provides CMP abrasive slurry that is substantially free of aluminum oxide and comprises liquid and solids wherein the solids comprises: (a) in an amount of at least about 90 weight percent based on the solids, at least one non-spherical component having formula Al 2 O 3 .xH 2 O where x ranges from 1 to 3; and (b) up to about one weight percent based on the solids portion of submicron alpha-alumina. The CMP abrasive slurry may be used to polish metallic or dielectric surfaces in computer wafers.

1 . CMP abrasive slurry that is substantially free of anhydrous aluminum oxide and comprises liquid and solids wherein said solids comprises: 
 (a) in an amount of at least about 90 weight percent based on said solids, at least one non-spherical component having formula Al 2 O 3 .xH 2 O where x ranges from 1 to 3; and    (b) up to about one weight percent based on said solids portion of submicron alpha-alumina.    
   
   
       2 . The CMP abrasive slurry of  claim 1  consisting essentially of said at least one non-spherical component having formula Al 2 O 3 .xH 2 O where x ranges from 1 to 3.  
   
   
       3 . The CMP abrasive slurry of  claim 1  wherein said non-spherical component is boehmite.  
   
   
       4 . The CMP abrasive slurry of  claim 1  wherein said non-spherical component comprises kaolin coated with boehmite.  
   
   
       5 . A method of planarization metal comprising the step of: 
 using the CMP abrasive slurry of  claim 1  to polish metal.    
   
   
       6 . The method of  claim 5  wherein planarization occurs in pH acidic conditions.  
   
   
       7 . The method of  claim 5  wherein said slurry is used to polish copper.