Cerium oxide slurry, cerium oxide polishing slurry and method for polishing substrate using the same

Abstract

The present invention provides a cerium oxide slurry, a cerium oxide polishing slurry, and a method of polishing a substrate by using the same, wherein decrease of scratches and polish at high speed can be realized by reducing the content of coarse grains by improving in the disperse state of cerium oxide particles. The invention relates to a cerium oxide slurry containing cerium oxide particles, dispersant and water, in which the ratio of weight of cerium oxide/weight of dispersant is in a range of 20 to 80 and relates a cerium oxide polishing slurry comprising the cerium oxide slurry and additives such as a water-soluble polymer.

1 . A cerium oxide slurry containing cerium oxide particles, dispersant and water, wherein the ratio of weight of cerium oxide/weight of dispersant is in a range of 20 to 80.  
   
   
       2 . The cerium oxide slurry according to  claim 1 , wherein the dispersant is a compound of which solubility in water is 0.1 wt. % to 99.9 wt. %.  
   
   
       3 . The cerium oxide slurry according to  claim 1  or  2 , wherein the dispersant is a salt of poly (meth)acrylic acid.  
   
   
       4 . The cerium oxide slurry according to  claim 1  or  2 , wherein the dispersant is ammonium salt polyacrylate or copolymer of polyacrylic acid-alkyl ammonium polyacrylate.  
   
   
       5 . A cerium oxide polishing slurry comprising the cerium oxide slurry according to  claim 1  or  2 , and a water-soluble polymer.  
   
   
       6 . The cerium oxide polishing slurry according to  claim 5 , wherein the cerium oxide polishing slurry is a one-pack storage type.  
   
   
       7 . The cerium oxide polishing slurry according to  claim 5 , wherein the cerium oxide polishing slurry is a two-pack storage type consisting of cerium oxide slurry, and an additive solution including water-soluble polymer and water.  
   
   
       8 . A polishing method of substrate comprising polishing a film to be polished by relatively moving a polishing table and a substrate having the film to be polished in the state that the substrate is pressed against a polishing cloth of the polishing table, while supplying the cerium oxide slurry according to  claim 1  or  2 .  
   
   
       9 . A polishing method of substrate comprising polishing a film to be polished by relatively moving a polishing table and a substrate having the film to be polished in the state that the substrate is pressed against a polishing cloth of the polishing table, while supplying the cerium oxide polishing slurry according to  claim 5  between the film to be polished and the polishing cloth.