Fixed abrasive polishing pad, method of preparing the same, and chemical mechanical polishing apparatus including the same

Abstract

A fixed abrasive polishing pad includes a base and a plurality of polishing layers on the base, wherein each polishing layer includes abrasive particles and apertures in a polishing surface of the polishing layer.

1 . A fixed abrasive polishing pad, comprising: 
 a base; and    a plurality of polishing layers on the base, wherein each polishing layer includes: 
 abrasive particles, and  
 apertures in a polishing surface of the polishing layer.  
   
     
     
         2 . The fixed abrasive polishing pad as claimed in  claim 1 , wherein at least some of the apertures are interconnected within the polishing layer.  
     
     
         3 . The fixed abrasive polishing pad as claimed in  claim 1 , wherein the apertures are formed using a foaming agent.  
     
     
         4 . The fixed abrasive polishing pad as claimed in  claim 1 , wherein the apertures have a predetermined pattern in the polishing surface.  
     
     
         5 . The fixed abrasive polishing pad as claimed in  claim 4 , wherein the predetermined pattern is a mold pattern.  
     
     
         6 . The fixed abrasive polishing pad as claimed in  claim 4 , wherein the apertures are arranged at regular intervals.  
     
     
         7 . The fixed abrasive polishing pad as claimed in  claim 4 , wherein the apertures have a regular shape.  
     
     
         8 . The fixed abrasive polishing pad as claimed in  claim 1 , wherein the apertures occupy about 5-50% of the polishing surface of each of the polishing layers.  
     
     
         9 . The fixed abrasive polishing pad as claimed in  claim 8 , wherein the apertures occupy about 5-30% of the polishing surface of each of the polishing layers.  
     
     
         10 . The fixed abrasive polishing pad as claimed in  claim 1 , wherein the polishing pad includes: 
 central polishing layers disposed in a center region; and    edge polishing layers disposed in an edge region, wherein the apertures in the polishing surface of the central polishing layers occupy a different area percentage of the polishing surface than do the apertures in the polishing surface of the edge polishing layers.    
     
     
         11 . The fixed abrasive polishing pad as claimed in  claim 10 , wherein the aperture area percentage in the central polishing layers is greater than the aperture area percentage in the edge polishing layers.  
     
     
         12 . A method of manufacturing a fixed abrasive polishing pad, the method comprising: 
 forming a base; and    disposing polishing layers on the base, each of the polishing layers including apertures in a polishing surface thereof and abrasive particles.    
     
     
         13 . The method as claimed in  claim 12 , wherein the apertures occupy about 5-50% of the polishing surface of each of the polishing layers.  
     
     
         14 . The method as claimed in  claim 13 , wherein the apertures occupy about 5-30% of the polishing surface of each of the polishing layers.  
     
     
         15 . The method as claimed in  claim 12 , wherein the apertures are formed by combining a foaming agent with a polymeric binder.  
     
     
         16 . The method as claimed in  claim 15 , wherein forming the polishing layers comprises: 
 forming a mixture including the polymeric binder and the foaming agent;    forming apertures in the mixture using the foaming agent;    distributing abrasive particles in the mixture; and    forming the polishing layers by processing the mixture including the distributed abrasive particles using a printing process.    
     
     
         17 . The method as claimed in  claim 16 , wherein the apertures are formed by heating the foaming agent.  
     
     
         18 . The method as claimed in  claim 15 , wherein the foaming agent includes at least one of Na 2 SO 4 , NaHCO 3 , ADCA, OBSH, and TSH.  
     
     
         19 . The method as claimed in  claim 12 , wherein the apertures are formed using a mold having a predetermined pattern therein, the pattern corresponding to a pattern of apertures in the polishing surface.  
     
     
         20 . The method as claimed in  claim 19 , wherein forming the apertures includes: 
 distributing abrasive particles in a UV-hardenable polymeric binder;    molding the polishing layers using the mold; and    irradiating the molded polishing layers with UV light.    
     
     
         21 . The method as claimed in  claim 19 , wherein forming the apertures includes: 
 distributing abrasive particles in a thermosetting polymeric binder;    molding the polishing layers using the mold; and    heating the molded polishing layers.    
     
     
         22 . The method as claimed in  claim 19 , wherein the mold includes a fine pattern of projections on a molding surface, the projections forming the apertures in the polishing surface.  
     
     
         23 . A chemical mechanical polishing apparatus, comprising: 
 a wafer carrier;    a fixed abrasive polishing pad including a base and polishing layers disposed on the base;    a slurry supplier; and    a supporter supporting the polishing pad, wherein each polishing layer includes: 
 abrasive particles, and  
 apertures formed in a polishing surface of the polishing layer.  
   
     
     
         24 . The chemical mechanical polishing apparatus as claimed in  claim 23 , wherein the polishing layers are formed using a foaming agent.  
     
     
         25 . The chemical mechanical polishing apparatus as claimed in  claim 23 , wherein the apertures have a predetermined pattern in the polishing surface.  
     
     
         26 . The chemical mechanical polishing apparatus as claimed in  claim 23 , wherein the chemical mechanical polishing apparatus is rotary type having a first roller for supplying the polishing pad, and a second roller for receiving a portion of the polishing pad that has performed a polishing process.