Method of making polishing pad assembly with glass or crystalline window

Abstract

Methods and apparatus for providing a chemical mechanical polishing pad. The pad includes a polishing layer having a top surface and a bottom surface. The pad includes an aperture having a first opening in the top surface and a second opening in the bottom surface. The top surface is a polishing surface. The pad includes a window that includes a first portion made of soft plastic and a crystalline or glass like second portion. The window is transparent to white light. The window is situated in the aperture so that the first portion plugs the aperture and the second portion is on a bottom side of the first portion, wherein the first portion acts a slurry-tight barrier.

1 . A method of making a polishing pad, the method comprising:
 placing a body of crystalline or glass like material in a mold of a polishing pad window;   dispensing a liquid precursor of a soft plastic material into the mold;   curing the liquid precursor to form a transparent window that includes a soft plastic first portion and a crystalline or glass second portion;   placing the window in a mold of a polishing pad;   dispensing a liquid precursor of a polishing pad material into the mold of the polishing pad; and   curing the liquid precursor of the polishing pad material to produce the polishing pad, wherein the window is situated in the mold of the polishing pad so that, when the polishing pad is produced, the window is situated in the polishing pad so the first portion has a surface that is coplanar with a polishing surface of the polishing pad and the first portion acts a slurry-tight barrier.   
     
     
         2 . The method of  claim 1 , wherein the body of crystalline or glass like material is quartz. 
     
     
         3 . The method of  claim 1 , wherein the liquid precursor comprises a urethane. 
     
     
         4 . The method of  claim 1 , wherein dispensing the liquid precursor of the soft plastic material comprises covering a non-planar surface on the body. 
     
     
         5 . The method of  claim 4 , wherein dispensing the liquid precursor of the soft plastic material comprises filling a recess in the body. 
     
     
         6 . The method of  claim 4 , wherein curing the liquid precursor forms the transparent window with the first portion having a greater thickness at edges of the window. 
     
     
         7 . The method of  claim 1 , wherein dispensing the liquid precursor of the soft plastic material comprises covering sides of the body. 
     
     
         8 . A method of making a polishing pad, the method comprising:
 placing a body of crystalline or glass materials in a mold of a polishing pad window;   dispensing a liquid precursor of a soft plastic material into the mold;   curing the liquid precursor to form a transparent window that includes a soft plastic first portion and a crystalline or glass second portion;   forming a polishing layer that includes an aperture, the polishing layer having a top surface and a bottom surface, the aperture having a first opening in the top surface and a second opening in the bottom surface, the top surface being a polishing surface; and   inserting the window in the aperture, the window being situated in the aperture so that the first portion has a surface that is coplanar with the polishing surface and the first portion plugs the aperture and acts a slurry-tight barrier and the second portion is on a bottom side of the first portion.   
     
     
         9 . The method of  claim 8 , wherein the body of crystalline or glass like material is quartz. 
     
     
         10 . The method of  claim 8 , wherein the liquid precursor comprises a urethane. 
     
     
         11 . The method of  claim 8 , wherein dispensing the liquid precursor of the soft plastic material comprises covering a non-planar surface on the body. 
     
     
         12 . The method of  claim 11 , wherein dispensing the liquid precursor of the soft plastic material comprises filling a recess in the body. 
     
     
         13 . The method of  claim 11 , wherein curing the liquid precursor forms the transparent window with the first portion having a greater thickness at edges of the window. 
     
     
         14 . The method of  claim 8 , wherein dispensing the liquid precursor of the soft plastic material comprises covering sides of the body. 
     
     
         15 . The method of  claim 8 , comprising attaching a side surface of each of the first portion and the second portion to the polishing pad with an adhesive. 
     
     
         16 . The method of  claim 15 , comprising applying an adhesive to one of the first portion or the second portion prior to inserting the window into the aperture.