Polyurethane, composition for formation of polishing layers that contains same, pad for chemical mechanical polishing, and chemical mechanical polishing method using same

Abstract

A polyurethane is produced by reacting a mixture including at least (A) a diisocyanate, (B) a polyol, and (C) a chain extender, the polyol (B) having the number average molecular weight of 400 to 5000, the chain extender (C) including (C1) a compound shown by the following general formula (1) and (C2) a compound shown by the following general formula (2), the compound (C1) and the compound (C2) having a number average molecular weight of less than 400, and a ratio “M 1 /(M 1 +M 2 )” calculated by using the number of moles (M 1 ) of the compound (C1) and the number of moles (M 2 ) of the compound (C2) being 0.25 to 0.9. HO—(CR 1 R 2 ) 2m+1 —OH  (1) HO—(CR 3 R 4 ) 2n —OH  (2)

1 - 10 . (canceled) 
     
     
         11 . A chemical mechanical polishing pad comprising:
 a polishing layer-forming composition, the polishing layer-forming composition comprising:   a polyurethane that is obtained by reacting a mixture comprising: (A) a diisocyanate; (B) a polyol; and (C) a chain extender;   wherein   a number average molecular weight of the polyol (B) is from 400 to 5000,   the chain extender (C) comprises:   (C1) a compound of formula (1),
   HO—(CR 1 R 2 ) 2m+1 —OH  (1)
 
   wherein R 1  and R 2  are each independently a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, and m is an integer from 1 to 13; and   (C2) a compound of formula (2),
   HO—(CR 3 R 4 ) 2n —OH  (2)
 
   wherein R 3  and R 4  are each independently a hydrogen atom or a substituted or unsubstituted an alkyl group having 1 to 6 carbon atoms, and n is an integer from 1 to 12, and   the compound (C1) and the compound (C2) have a number average molecular weight of less than 400, and   M 1 /(M 1 +M 2 ) is from 0.25 to 0.9,   wherein M 1  is an amount of the compound (C1) in moles and M 2  is an amount of the compound (C2) in moles.   
     
     
         12 . The chemical mechanical polishing pad of  claim 11 , wherein R 1  and R 2  are each a hydrogen atom. 
     
     
         13 . The chemical mechanical polishing pad of  claim 11 , wherein the compound (C1) is at least one compound selected from the group consisting of 1,3-propandiol and 1,5-pentanediol. 
     
     
         14 . The chemical mechanical polishing pad of  claim 11 , wherein R 3  and R 4  are each a hydrogen atom. 
     
     
         15 . The chemical mechanical polishing pad of  claim 11 , wherein the compound (C2) is at least one compound selected from the group consisting of ethylene glycol, 1,4-butanediol, 1,6-hexanediol, and 1,18-octanediol. 
     
     
         16 . The chemical mechanical polishing pad of  claim 11 , wherein the polishing layer-forming composition further comprises water-soluble particles. 
     
     
         17 . The chemical mechanical polishing pad of  claim 11 , wherein the polishing layer-forming composition further comprises a crosslinking agent. 
     
     
         18 . The chemical mechanical polishing pad of  claim 11 , wherein the polyol (B) is selected from the group consisting of a hydroxyl-terminated polyester, a polyether polyol, a polybutylene adipate polyol, a polyhexamethylene adipate polyol, a polycaprolactam polyol, a polycarbonate polyol, a polyolefin polyol, a polyester carbonate polyol, a polyether carbonate polyol, and a polyester amide polyol.