Chemical mechanical polishing pad, manufacturing process thereof and chemical mechanical polishing method for semiconductor wafers

Abstract

There is provided a chemical mechanical polishing pad containing a polishing substrate having a polishing surface and a light-transmitting member fused to the polishing substrate. The sectional form of the light-transmitting member when it is cut with a plane parallel to the polishing surface is elliptic with a value obtained by dividing its long diameter by its short diameter of more than 1. The pad is capable of transmitting end-point detection light without reducing its polishing efficiency in polishing a semiconductor wafer.

1 . A chemical mechanical polishing pad comprising a polishing substrate having a polishing surface and a light-transmitting member fused to the polishing substrate, the sectional form of the light-transmitting member when it is cut with a plane parallel to the polishing surface being elliptic with a value obtained by dividing its long diameter by its short diameter of more than 1.  
   
   
       2 . The chemical mechanical polishing pad according to  claim 1 , wherein the light-transmitting member comprises a water-insoluble material and water-soluble particles dispersed in the water-insoluble material.  
   
   
       3 . The chemical mechanical polishing pad according to  claim 2 , wherein at least part of the water-insoluble material is a crosslinked polymer.  
   
   
       4 . The chemical mechanical polishing pad according to  claim 3 , wherein the crosslinked polymer is 1,2-polybutadiene.  
   
   
       5 . A process for manufacturing the chemical mechanical polishing pad of  claim 1 , comprising fusing the polishing substrate to the light-transmitting member in a metal mold for insert molding.  
   
   
       6 . A method for the chemical mechanical polishing of a semiconductor wafer with the chemical mechanical polishing pad of  claim 1 , comprising detecting the end point of chemical mechanical polishing with an optical end-point detector through the light-transmitting member of the chemical mechanical polishing pad of  claim 1.