Chemical mechanical polishing pads having a consistent pad surface microtexture

Abstract

The present invention provides pre-conditioned chemical mechanical (CMP) polishing pads comprising a polymer, preferably, a porous polymer having a pad surface microtexture effective for polishing having a series of visibly intersecting arcs on the polishing layer surface, the intersecting arcs having a radius of curvature equal to or greater than half of the radius of curvature of the pad and extending all the way around the surface of the pad in radial symmetry around the center point of the pad wherein the resulting CMP polishing pad has a surface roughness of from 0.01 μm to 25 μm, Sq. The CMP polishing pads may be made by methods comprising grinding the surface of a CMP polishing pad with a rotary grinder to form the surface microtexture.

We claim: 
     
         1 . A chemical mechanical (CMP) polishing pad comprising a CMP polishing layer of one or more polymer, the CMP polishing layer having a radius, having a surface roughness of from 0.01 μm to 25 μm, Sq, and having a series of visibly intersecting arcs on the polishing layer surface, the intersecting arcs having a radius of curvature equal to or greater than half of the radius of curvature of the polishing layer and extending all the way around the surface of the polishing layer in radial symmetry around the center point of the polishing layer. 
     
     
         2 . The chemical mechanical (CMP) polishing pad as claimed in  claim 1 , comprising a porous CMP polishing layer of one or more polymer. 
     
     
         3 . The chemical mechanical (CMP) polishing pad as claimed in  claim 2 , wherein the CMP polishing layer comprises a porous polymer or a filled porous polymer material that has a Shore D hardness according to ASTM D2240-15 (2015) of from 20 to 80. 
     
     
         4 . The chemical mechanical (CMP) polishing pad as claimed in  claim 3 , wherein the CMP polishing layer comprises a porous polymer or a filled porous polymer material that has a Shore D hardness according to ASTM D2240-15 (2015) of 40 or less. 
     
     
         5 . The chemical mechanical (CMP) polishing pad as claimed in  claim 1 , wherein the one or more polymer is a polyurethane. 
     
     
         6 . The chemical mechanical (CMP) polishing pad as claimed in  claim 1 , wherein the intersecting arcs have a radius of curvature equal to half of the radius of curvature of the CMP polishing layer. 
     
     
         7 . The chemical mechanical (CMP) polishing pad as claimed in  claim 1 , wherein the CMP polishing layer has annular bands of alternating higher density and lower density extending outward from the center point of the CMP polishing layer toward its outer periphery. 
     
     
         8 . The chemical mechanical (CMP) polishing pad as claimed in  claim 1 , wherein the polishing pad has one or more non-porous and clear window sections not extending over the center point of the CMP polishing pad, wherein the one or more window sections has a top surface defined by a window thickness variation of 50 μm or less over the largest dimension of the window. 
     
     
         9 . The chemical mechanical (CMP) polishing pad as claimed in  claim 1 , wherein the CMP polishing layer is stacked on a subpad or subbing layer. 
     
     
         10 . The chemical mechanical (CMP) polishing pad as claimed in  claim 9 , wherein the subpad or subbing layer is a polymer impregnated nonwoven mat.