Aqueous dispersion for chemical mechanical polishing and production process of semiconductor device

Abstract

The invention provides an aqueous dispersion for chemical mechanical polishing, by which scratches are reduced even for an article to be polished having a dielectrics low in mechanical strength, both copper film and barrier metal film can be polished with high efficiency, and a sufficiently planarized finished surface with high precision can be provided without overpolishing the dielectrics, and a production process of a semiconductor device. The aqueous dispersion for chemical mechanical polishing comprises abrasive grains, wherein the abrasive grains include (A) simple particles composed of at least one selected from inorganic particles and organic particles, and (B) composite particles. It is preferred that the simple particles (A) are composed of inorganic particles and composite particles (B) are composed of inorganic organic composite particles that formed of organic particles and inorganic particles combined integraly. The production process of a semiconductor device comprises the step of polishing a surface to be polished of a semiconductor material with the aqueous dispersion for polishing.

What is claimed is:  
     
         1 . An aqueous dispersion for chemical mechanical polishing comprising abrasive grains, wherein the abrasive grains include: 
 (A) simple particles composed of at least one selected from inorganic particles and organic particles, and    (B) composite particles.    
     
     
         2 . The aqueous dispersion for chemical mechanical polishing according to  claim 1 , wherein the simple particles (A) making up the abrasive grains are composed of inorganic particles, and the composite particles (B) are composed of inorganic organic composite particles obtained by integrally combining organic particles with inorganic particles.  
     
     
         3 . The aqueous dispersion for chemical mechanical polishing according to  claim 1  or  2 , wherein the overall content of all the abrasive grains is 0.11 to 20% by mass, the content of the simple particles (A) is 0.1 to 19.99% by mass, and the content of the composite particles (B) is 0.01 to 19.9% by mass.  
     
     
         4 . The aqueous dispersion for chemical mechanical polishing according to any one of  claims 1  to  3 , wherein a value of a specific removal rate ratio (RBM/RCu) represented by a ratio of the removal rate (RBM) of a barrier metal film to the removal rate (RCu) of a copper film in the case where the copper film and barrier metal film are polished under the same conditions is 0.5 to 200.  
     
     
         5 . The aqueous dispersion for chemical mechanical polishing according to any one of  claims 1  to  3 , wherein the value of the specific removal rate ratio (RBM/RCu) represented by a ratio of the removal rate (RBM) of a barrier metal film to the removal rate (RCu) of a copper film in the case where the copper film and barrier metal film are polished under the same conditions is 10 to 200.  
     
     
         6 . The aqueous dispersion for chemical mechanical polishing according to any one of  claims 1  to  3 , wherein the value of the specific removal rate ratio (RBM/RCu) represented by a ratio of the removal rate (RBM) of a barrier metal film to the removal rate (RCu) of a copper film in the case where the copper film and barrier metal film are polished under the same conditions is 0.5 to 3.  
     
     
         7 . A process for producing a semiconductor device, comprising the step of polishing a surface to be polished of a semiconductor material with the aqueous dispersion for chemical mechanical polishing according to any one of  claims 1  to  6 .  
     
     
         8 . A process for producing a semiconductor device, comprising the first polishing treatment step of mainly polishing a copper film of a surface to be polished of a semiconductor material and the second polishing treatment step of mainly polishing a barrier metal film with the aqueous dispersion for chemical mechanical polishing according to  claim 5  or  6 , conducted after the first polishing treatment step.