Single-layer polishing pad

Abstract

A foamed plastic is cut to form a single-layer polishing pad having a desired rigidity and compressibility. A polishing surface of the polishing pad has a higher density than a mounting surface of the polishing pad. The polishing surface and the mounting surface may have different areas having different densities for achieving desired rigidity and compressibility property. Furthermore, methods of making such single-layer polishing pads are also disclosed.

1 . A single-layer polishing pad, comprising: 
 a body comprising a porous polymer;    a polishing surface, having at least a first region and at least a second region over different areas, on one side of the body, wherein the density of the first region is lower than the density of the second region; and    a mounting surface on another side of the body.    
     
     
         2 . The single-layer polishing pad of  claim 1 , wherein the density of the first region of the polishing surface is higher than the density of the mounting surface.  
     
     
         3 . The single-layer polishing pad of  claim 1 , wherein a shape of the first region is a sector, a ring or a circle.