Ceria slurry for polishing semiconductor thin layer

Abstract

A non-agglomerating ceria aqueous slurry, which has good dispersion stability and reduced generation of scratches with excellent polishing productivity, comprises ceria particles having a mean volume particle size ranging from 0.1 to 0.2 μm and is characterized in that when it is centrifuged under an applied average centrifugal force (g) of 1,970 g 0 for 2 minutes, g 0 being acceleration of gravity, the amount of the solid content reduction is 20% by weight or less.

1 . A ceria aqueous slurry for polishing a semiconductor thin layer, comprising ceria particles having a mean volume particle size ranging from 0.1 to 0.2 μm, the slurry being characterized in that when it is centrifuged under an applied average centrifugal force (g) of 1,970 g 0  for 2 minutes, g 0  being acceleration of gravity, the amount of the solid content reduction is 20% by weight or less.  
   
   
       2 . The ceria aqueous slurry of  claim 1 , which is obtained by dispersing a ceria powder in water to a concentration of 0.5 to 20 wt % and centrifuging the resulting slurry at a rotation speed of 1,000 to 5,000 rpm.  
   
   
       3 . The ceria aqueous slurry of  claim 2 , wherein centrifuging is carried out by passing the slurry through a cylindrical centrifuge.  
   
   
       4 . A method for polishing the surface of a thin film layer of a semiconductor or insulating material using the ceria aqueous slurry of  claim 1 .  
   
   
       5 . The method of  claim 4 , wherein the semiconductor thin layer is employed for a micropattern having a line width of below 0.16 μm.