Polishing composition and polishing method

Abstract

A first polishing composition includes abrasive grains and an iodine compound and has a pH of 6 or more. The first polishing composition can suitably polish the Si [0001] plane of a single crystal silicon carbide substrate. A second polishing composition includes an iodine compound and has a pH of 8 or less. The second polishing composition can suitably polish the C [000-1] plane of a single crystal silicon carbide substrate. A third polishing composition includes abrasive grains and an iodine compound and has a pH of 6 to 8, inclusive. The third polishing composition can suitably polish each of the Si [0001] and C [000-1] planes of a single crystal silicon carbide substrate.

1 . A polishing composition comprising abrasive grains and an iodine compound and having a pH of 6 or more.  
   
   
       2 . The polishing composition according to  claim 1 , wherein the iodine compound includes iodic acid, periodic acid or a salt thereof.  
   
   
       3 . The polishing composition according to  claim 1 , further comprising an alkali including a lithium compound or ammonia.  
   
   
       4 . The polishing composition according to  claim 1 , wherein the polishing composition is used for polishing an object formed of single crystal silicon carbide.  
   
   
       5 . A method for polishing an object formed of single crystal silicon carbide, comprising: 
 preparing a polishing composition including abrasive grains and an iodine compound and having a pH of 6 or more; and    polishing said object using the prepared polishing composition.    
   
   
       6 . A polishing composition for use in polishing an object formed of single crystal semiconductor, comprising an iodine compound and having a pH of 8 or less.  
   
   
       7 . The polishing composition according to  claim 6 , further comprising abrasive grains.  
   
   
       8 . The polishing composition according to  claim 6 , wherein the iodine compound includes iodic acid, periodic acid or a salt thereof.  
   
   
       9 . The polishing composition according to  claim 6 , wherein the object is formed of single crystal silicon carbide.  
   
   
       10 . A method for polishing an object formed of single crystal silicon carbide, comprising: 
 preparing a polishing composition including an iodine compound and having a pH of 8 or less; and    polishing said object using the prepared polishing composition.    
   
   
       11 . A polishing composition for use in polishing an object formed of single crystal silicon carbide, comprising abrasive grains and an iodine compound and having a pH of 6 to 8, inclusive.  
   
   
       12 . The polishing composition according to  claim 11 , wherein the iodine compound includes iodic acid, periodic acid or a salt thereof.  
   
   
       13 . A method for polishing an object formed of single crystal silicon carbide, comprising: 
 preparing a polishing composition including abrasive grains and an iodine compound, and having a pH of 6 to 8; and    polishing the object using the prepared polishing composition.