Polishing pad with concentric or approximately concentric polygon groove pattern

Abstract

Polishing pads with concentric or approximately concentric polygon groove patterns are described. Methods of fabricating polishing pads with concentric or approximately concentric polygon groove patterns are also described.

What is claimed is: 
     
         1 . A polishing pad for polishing a substrate, the polishing pad comprising:
 a polishing body having a polishing surface and a back surface, the polishing surface having a pattern of grooves comprising a plurality of discrete linear segments orthogonal or approximately orthogonal to radii of the polishing surface.   
     
     
         2 . The polishing pad of  claim 1 , wherein the plurality of discrete linear segments orthogonal or approximately orthogonal to radii of the polishing surface form a portion of a, but not a complete, concentric or approximately concentric polygon arrangement. 
     
     
         3 . The polishing pad of  claim 2 , wherein the portion of the concentric or approximately concentric polygon arrangement omits one or more inflection points from one or more of the polygons. 
     
     
         4 . The polishing pad of  claim 2 , wherein the portion of the concentric or approximately concentric polygon arrangement omits one or more edges from one or more of the polygons. 
     
     
         5 . The polishing pad of  claim 1 , wherein the pattern of grooves has no radial groove. 
     
     
         6 . The polishing pad of  claim 1 , wherein the pattern of grooves has a radial groove along a radius of the polishing surface, but not in contact with the plurality of discrete linear segments. 
     
     
         7 . A polishing pad for polishing a substrate, the polishing pad comprising:
 a polishing body having a polishing surface and a back surface, the polishing surface having a pattern of grooves comprising nested incomplete polygons having continuity there between.   
     
     
         8 . The polishing pad of  claim 7 , wherein the pattern of grooves has no radial groove. 
     
     
         9 . The polishing pad of  claim 7 , wherein the pattern of grooves has a radial groove along a radius of the polishing surface. 
     
     
         10 . A polishing pad for polishing a substrate, the polishing pad comprising:
 a polishing body having a polishing surface and a back surface, the polishing surface having a pattern of grooves comprising concentric or approximately concentric polygons, the pattern of grooves having no radial groove continuous from the inner most polygon to the outer most polygon, wherein one of the polygons has a different number of edges than another of the polygons.   
     
     
         11 . The polishing pad of  claim 10 , wherein the outer most polygon has more edges than the inner most polygon. 
     
     
         12 . The polishing pad of  claim 10 , wherein the center of the concentric polygons is located at a center of the polishing pad. 
     
     
         13 . A method of fabricating a polishing pad for polishing a substrate, the method comprising:
 mixing a pre-polymer and a curative to form a mixture in the base of a formation mold;   moving the lid of the formation mold into the mixture, the lid having disposed thereon a pattern of protrusions comprising concentric or approximately concentric polygons, the pattern of protrusions having no radial protrusion continuous from the inner most polygon to the outer most polygon; and, with the lid placed in the mixture,   at least partially curing the mixture to form a molded homogeneous polishing body comprising a polishing surface having disposed therein a pattern of grooves corresponding to the pattern of protrusions of the lid.   
     
     
         14 . The method of  claim 13 , wherein forming the molded homogeneous polishing body comprises forming a thermoset polyurethane material. 
     
     
         15 . The method of  claim 13 , wherein the mixing further comprises adding a plurality of porogens to the pre-polymer and the curative to form a plurality of closed cell pores in the molded homogeneous polishing body, each closed cell pore having a physical shell. 
     
     
         16 . The method of  claim 13 , wherein the mixing further comprises injecting a gas into the pre-polymer and the curative, or into a product formed there from, to form a plurality of closed cell pores in the molded homogeneous polishing body, each closed cell pore having no physical shell. 
     
     
         17 . The method of  claim 13 , wherein mixing the pre-polymer and the curative comprises mixing an isocyanate and an aromatic diamine compound, respectively. 
     
     
         18 . The method of  claim 13 , wherein the mixing further comprises adding an opacifying lubricant to the pre-polymer and the curative to form an opaque molded homogeneous polishing body. 
     
     
         19 . The method of  claim 13 , wherein curing the mixture comprises first partially curing in the formation mold and then further curing in an oven. 
     
     
         20 . The method of  claim 13 , wherein the pattern of protrusions has no radial protrusions.