Polishing pad, pad dressing evaluation method, and polishing apparatus

Abstract

The present invention provides: a polishing apparatus for polishing a workpiece, comprising a polishing pad whose surface or surface layer part is colored with a color different from a color inside the polishing pad, a pad dresser which performs dressing of the polishing pad, and an observing device which observes the surface of the polishing pad; and a method for simply and accurately monitoring the uniformity of dressing state of a polishing pad in dressing the polishing pad of a polishing apparatus such as a CMP device, in order to prolong the life of the polishing pad, and to reduce the number of dummy wafers used in the pad dressing.

1 . A polishing pad of a polishing apparatus for polishing a workpiece, comprising 
 a surface or a surface layer part of the polishing pad which is colored with a color different from a color inside the polishing pad.    
   
   
       2 . A pad dressing evaluation method for evaluating a dressing state of pad dressing by which the surface of a polishing pad of a polishing apparatus is dressed, comprising the steps of: 
 performing the pad dressing for a predetermined time period by using the polishing pad whose surface is colored, or whose surface or surface layer part is colored beforehand with a color different from a color inside the polishing pad; and    evaluating the dressing state of the pad dressing on the basis of color irregularity of the polishing pad surface ground by the pad dressing.    
   
   
       3 . The pad dressing evaluation method according to  claim 2 , wherein 
 the color irregularity of the polishing pad surface is obtained by measuring and quantifying color of the polishing pad surface ground by the pad dressing at plural points.    
   
   
       4 . The pad dressing evaluation method according to  claim 2 , wherein 
 the evaluation of the dressing state is to evaluate dressing uniformity in the surface of the polishing pad.    
   
   
       5 . The pad dressing evaluation method according to  claim 3 , wherein 
 the evaluation of the dressing state is to evaluate dressing uniformity in the surface of the polishing pad.    
   
   
       6 . A polishing apparatus for polishing a workpiece, comprising: 
 a polishing pad whose surface or surface layer part is colored with a color different from a color inside the polishing pad;    a pad dresser which performs dressing of the polishing pad; and    an observing device which observes the surface of the polishing pad.    
   
   
       7 . A polishing apparatus for polishing a workpiece, comprising: 
 a polishing pad whose surface or surface layer part is colored with a color different from a color inside the polishing pad;    a pad dresser which performs dressing of the polishing pad; and    a measuring device which measures and quantifies a color of the polishing pad surface.    
   
   
       8 . The polishing apparatus according to  claim 7 , further comprising a judging device which judges whether or not the quantified values are within a range set beforehand, and thereby judges whether or not polishing of the workpiece is performed.