Method for polishing semiconductor wafer and polishing pad for the same

Abstract

On the surface of a belt-type surface plate wound around two rollers whose rotation axes are arranged in parallel with each other, four or other number of sheet-shaped polishing pads of polyurethane are stuck. Each of the polishing pads has grooves extending in the same direction as the drive direction of the surface plate. Moreover, the polishing pads adjacently arranged in the drive direction of the surface plate are stuck apart in such a manner that the grooves of one polishing pad are spaced not to align with the respective grooves of the other polishing pad.

What is claimed is:  
     
         1 . A method for polishing a semiconductor wafer, in which the semiconductor wafer is polished by continuously driving a surface plate on which a plurality of polishing pads are stuck, the surface of each of the polishing pads being provided with a plurality of grooves each extending in the drive direction of the pad, 
 the method comprising the steps of: 
 sticking the plurality of polishing pads on the surface of the surface plate; and  
 polishing the semiconductor wafer by pressing the wafer against the surface of each said polishing pad with the surface plate driven,  
 wherein in the sticking step, the polishing pads are stuck in such a manner that the grooves of each said polishing pad are spaced not to align with the respective grooves of the polishing pad adjacently arranged in the drive direction of the surface plate.  
   
     
     
         2 . The method of  claim 1 , wherein in the sticking step, the polishing pads are stuck in such a manner that the grooves of each said polishing pad are offset by a predetermined distance from the respective grooves of the polishing pad adjacently arranged in the drive direction.  
     
     
         3 . The method of  claim 1 , wherein in the polishing step, the semiconductor wafer is polished with slurry containing abrasives flowing on the surfaces of the polishing pads.  
     
     
         4 . A polishing pad for a semiconductor wafer, 
 wherein the polishing pad is stuck on the surface of a belt-type surface plate, and    a plurality of grooves extending in the drive direction of the polishing pad are formed over the entire width from edge to edge of the polishing pad in the direction perpendicular to the drive direction.    
     
     
         5 . The pad of  claim 4 , wherein the plurality of grooves are formed at regular intervals.  
     
     
         6 . The pad of  claim 4 , wherein the polishing pad is made of polyurethane foam.  
     
     
         7 . A polishing pad for a semiconductor wafer, 
 wherein the polishing pad is stuck on the surface of a belt-type surface plate, and    in the surface of the polishing pad, a plurality of grooves extending in the drive direction of the polishing pad are formed at an angle relative to the drive direction.    
     
     
         8 . The pad of  claim 7 , wherein the plurality of grooves are formed at regular intervals.  
     
     
         9 . The pad of  claim 7 , wherein the polishing pad is made of polyurethane foam.