Wafer polishing pad and method of wafer polishing using the same

Abstract

A wafer polishing pad includes a first pad having a first surface configured to receive a platen. A protrusion is disposed on the first surface of the first pad. The protrusion is disposed on an edge region of the first pad in a plan view such that a side surface of the protrusion makes contact with a side surface of the platen when the first pad is disposed on the platen.

1 . A wafer polishing pad, comprising:
 a first pad having a first surface configured to receive a platen; and   a protrusion disposed on the first surface of the first pad,   wherein the protrusion is disposed on an edge region of the first pad in a plan view such that a side surface of the protrusion makes contact with a side surface of the platen when the first pad is disposed on the platen.   
     
     
         2 . The wafer polishing pad of  claim 1 , wherein the protrusion exposes a central region of the first surface of the first pad, and when viewed in the plan view, the protrusion circumscribes the central region of the first pad. 
     
     
         3 . The wafer polishing pad of  claim 1 , wherein the protrusion comprises a vent groove disposed within a bottom surface of the protrusion. 
     
     
         4 . The wafer polishing pad of  claim 3 , wherein a floor surface of the vent groove is located at substantially a same level as that of the first surface of the first pad. 
     
     
         5 . The wafer polishing pad of  claim 3 , further comprising a mark disposed on the bottom surface of the protrusion. 
     
     
         6 . The wafer polishing pad of  claim 3 , further comprising an adhesive layer covering a portion of the first surface of the first pad,
 wherein the portion of the first surface of the first pad is exposed by the protrusion.   
     
     
         7 . The wafer polishing pad of  claim 1 , wherein a groove is disposed on a second surface of the first pad,
 wherein the second surface of the first pad is opposite to the first surface.   
     
     
         8 . The wafer polishing pad of  claim 1 , further comprising:
 a second pad disposed on the first pad; and   an adhesive layer disposed between the first pad and the second pad.   
     
     
         9 . The wafer polishing pad of  claim 8 , wherein a groove is disposed on a second surface of the second pad,
 wherein the second surface of the second pad faces away from the first pad.   
     
     
         10 . The wafer polishing pad of  claim 1 , wherein a topmost portion of an edge region of a second surface of the first pad is located at substantially the same level as that of a topmost portion of a central region of the second surface of the first pad,
 wherein the second surface of the first pad is opposite to the first surface of the first pad.   
     
     
         11 . A wafer polishing pad, comprising:
 a top surface including a groove;   a first bottom surface opposite to the top surface and corresponding to a central region of the polishing pad; and   a second bottom surface opposite to the top surface and corresponding to an edge region of the polishing pad,   wherein the second bottom surface is located at a lower level than that of the first bottom surface.   
     
     
         12 . The wafer polishing pad of  claim 11 , wherein the second bottom surface has a closed loop shape. 
     
     
         13 . The wafer polishing pad of  claim 11 , further comprising a vent groove disposed within the second bottom surface,
 wherein a floor surface of the vent groove is connected to the first bottom surface.   
     
     
         14 . The wafer polishing pad of  claim 13 , further comprising an adhesive layer disposed on the first bottom surface. 
     
     
         15 - 20 . (canceled) 
     
     
         21 . A wafer polishing pad, comprising:
 a polishing surface configured to mechanically polish a wafer;   a receiving surface, opposite to the polishing surface, configured to make contact with a top surface of a platen; and   a ring disposed on the receiving surface and configured to make contact with a side surface of the platen.   
     
     
         22 . The wafer polishing pad of  claim 21 , wherein the ring of the polishing wafer is configured to buttress a portion of the polishing surface that extends beyond the platen. 
     
     
         23 . The wafer polishing pad of  claim 21 , wherein the wafer polishing pad comprises a first pad and a second pad that are joined together by an adhesive layer, the first pad including the polishing surface and the second pad including the receiving surface.