Chemical-mechanical polishing (CMP) slurry containing clay and CeO2 abrasive particles and method of planarizing surfaces

Abstract

A composition for planarizing or polishing a surface comprising (a) a liquid carrier, and (b) solids comprising about 0.1 to about 10% by weight clay abrasive particles, and about 0.1% to about 50% by weight CeO 2 particles, based on the total weight of solids in the composition, said clay and CeO 2 abrasive particles having a particle size such that at least 90% of the particles (by number), when slurried in water, have a particle size in the range of about 10 nm to about 10 μm.

1 . A composition for planarizing or polishing a surface comprising (a) a liquid carrier, and (b) solids comprising about 0.1 to about 10% by weight clay abrasive particles, and about 0.1% to about 50% by weight CeO2 particles, based on the total weight of the composition, said clay abrasive particles having a particle size such that at least 90% of the particles, by number, when dispersed in water, have a particle size in the range of about 10 nm to about 10 μm, and the CeO2 abrasive particles having a particle size such that at least 90% of the particles, by number, when dispersed in water, have a particle size in the range of larger than 0.1 μm to about 10 μm.  
     
     
         2 . The composition of  claim 1  wherein the clay abrasive particles comprise a smectite clay.  
     
     
         3 . The composition of  claim 1 , wherein the solids are present in the composition in an amount of about 0.1 to about 60 wt. % of the composition.  
     
     
         4 . The composition of  claim 1 , wherein the carrier is water.  
     
     
         5 . The composition of  claim 1 , further including a chemical accelerator selected from a peroxide, a sulfate, a persulfate, or a nitrate.  
     
     
         6 . The composition of  claim 5 , wherein the chemical accelerator is selected from the group consisting of hydrogen peroxide, ammonium persulfate, iron (III) nitrate, and hydroxylamine nitrate.  
     
     
         7 . The composition of  claim 1 , wherein the clay is selected from the group consisting of a smectite clay; a kaolinite clay; a serpentine clay; a Pyrophyllite clay; talc, mica, and a synthetic clay.  
     
     
         8 . The composition of  claim 7 , wherein the clay is selected from the group consisting of Beidellite; Nontsonite; Volkonskoite; Saponite; Hectorite; Halloysite; Kaolin; Serpentine clays, such as Lizardite; Amesite; Chrysotile; Pyrophyllite; Talc; Illite; Vermiculite; a synthetic smectite; Japonite; and a combination thereof.  
     
     
         9 . The composition of  claim 8 , wherein the clay is a smectite clay selected from the group consisting of bentonite, montmorillonite, and combinations thereof.  
     
     
         10 . The composition of  claim 1 , wherein the clay abrasive particles have a particle size such that at least 90% of the particles are in the range of 50 nm to 51 μm.  
     
     
         11 . The composition of  claim 10 , wherein the CeO2 abrasive particles each have a particle size such that at least 90% of the particles are in the range of larger than 0.1 μm to 4 μm.  
     
     
         12 .- 17 . (canceled)