Slurry for chemical mechanical polishing of cobalt

Abstract

A slurry for chemical mechanical polishing of Co. The slurry comprises components by weight as follows, Inhibitor 0.01-2%, Oxidant 0-5%, Abrasive 0.1-10%, Complexing agent 0.001-10%, and the rest of water. The pH value of the slurries is adjusted to 3-5 by a pH value adjustor. The inhibitor is chosen from one or more kinds of five-membered heterocycle compound containing S and N atoms or containing S or N atom. The oxidant is one or more chosen from H 2 O 2 , (NH 4 ) 2 S 2 O 8 , KIO 4 , and KClO 5 . The abrasive is one or more chosen from SiO 2 , CeO 2 , and Al 2 O 3 . The complexing agent is one or more chosen from amino acid and citric acid. The slurry can effectively prevent Co over corrosion and reduce the polishing rate of Co in the polishing process.

1 . A slurry for chemical mechanical polishing of Co, comprises components by weight as follows, inhibitor 0.01-2%, oxidant 0-5%, abrasive 0.1-10%, complexing agent 0.001-10%, and the rest of water; the pH value of the slurry is adjusted to 3-5 by pH value adjustor;
 said inhibitor is chosen from one or more kinds of five-membered heterocycle compound containing S and N atoms or containing S or N atom;   said oxidant is chosen one or more from H 2 O 2 , (NH 4 ) 2 S 2 O 8 , KIO 4 , KClO 5 ;   said abrasive is chosen one or more from SiO 2 , CeO 2 , and Al 2 O 3 ;   said complexing agent is chosen one or more from amino acid and citric acid.   
     
     
         2 . The slurry for chemical mechanical polishing of Co of  claim 1 , wherein said slurry comprises components by weight as follows, inhibitor 0.01-1%, oxidant 0.5-2%, abrasive 1-5%, complexing agent 0.4%, and the rest of water. 
     
     
         3 . The slurry for chemical mechanical polishing of Co of  claim 1  or  claim 2 , wherein said five-membered heterocycle compound chosen as inhibitor has two heteroatoms in ring. 
     
     
         4 . The slurry for chemical mechanical polishing of Co of  claim 3 , wherein said inhibitor is chosen one or more from Benzotriazole, 2-mercaptothiazole, 2-mercaptobenzothiazole, imidazole, 2-Aminobenzimidazole, 2-Mercaptobenzimidazole and 2-Methylbenzimidazole. 
     
     
         5 . The slurry for chemical mechanical polishing of Co of  claim 4 , wherein said inhibitor is mixing of Benzotriazole and 2-mercaptothiazole. 
     
     
         6 . The slurry for chemical mechanical polishing of Co of  claim 1  or  claim 2  or  claim 4  or  claim 5 , wherein said particle size of the abrasive is in the range of 10-100 nm. 
     
     
         7 . The slurry for chemical mechanical polishing of Co of  claim 1  or  claim 2  or  claim 4  or  claim 5 , wherein said complexing agent is chosen one or more from glycine, glutamic, leucine and arginine acid. 
     
     
         8 . The slurry for chemical mechanical polishing of Co of  claim 7 , wherein said complexing agent is glycine acid. 
     
     
         9 . The slurry for chemical mechanical polishing of Co of  claim 1 , the pH value adjustor is chosen one or more from nitric acid, sulphuric acid, dilute acetic acid, hydrochloric acid, potassium hydroxide, sodium hydroxide, sodium carbonate and sodium bicarbonate. 
     
     
         10 . The application of the slurry for chemical mechanical polishing of Co according to  claim 1  in polishing process.