Polishing pad with array of fluidized gimballed abrasive members

Abstract

An abrasive article with an array of independently gimballed abrasive members that are capable of selectively engaging with nanometer-scale and/or micrometer-scale height variations and micrometer-scale and/or millimeter-scale wavelengths of waviness, on the surfaces of substrates. Each abrasive member maintains a fluid bearing (air is the typical fluid) with the substrate. The spacing and pitch of the abrasive members can be adjusted to follow the topography of the substrate to remove a generally uniform layer of material; to engage with the peaks on the substrate to remove target wavelengths of waviness; and/or to remove debris and contamination from the surface of the substrate.

1 . An abrasive article for polishing a surface of a substrate, the abrasive article comprising:
 a gimbal structure including a plurality of gimbal assemblies;   a plurality of abrasive members comprising a first surface engaged with one of the gimbal assemblies, and a second surface, the gimbal assemblies permitting each abrasive member to move independently along a pitch axis and a roll axis;   a preload mechanism that biases the second surfaces of the abrasive members toward the substrate; and   a fluid bearing feature on the second surface of at least some of the plurality of the abrasive members configured to generate lift forces during motion of the abrasive article relative to the substrate.   
     
     
         2 . The abrasive article of  claim 1  wherein the fluid bearing feature comprises an abrasive material attached to the second surface of the abrasive member. 
     
     
         3 . The abrasive article of  claim 1  further comprising, a slurry of free abrasive particles located at the interface of the second surface and the substrate. 
     
     
         4 . The abrasive article of  claim 1  wherein the plurality of abrasive members comprises an interconnected array of molded abrasive members. 
     
     
         5 . The abrasive article of  claim 1  wherein the plurality of abrasive members are arranged in a patterned array 
     
     
         6 . The abrasive article of  claim 1  wherein the plurality of abrasive members are arranged in a random pattern. 
     
     
         7 . The abrasive article of  claim 1  wherein the fluid bearing feature comprises a fluid bearing feature a leading edge of the second surface and a fluid bearing surface at a trailing edge of the second surface of the abrasive members. 
     
     
         8 . The abrasive article of  claim 1  wherein the fluid bearing features include abrasive composites. 
     
     
         9 . An abrasive article for polishing a surface of a substrate, the abrasive article comprising:
 an integrated structure including a plurality of gimbal assemblies and a plurality of preload structures;   a plurality of abrasive members each comprising
 a first surface engaged with one of the integrated gimbal assemblies and one of the preload structures; and 
 a second surface for polishing the substrate, the gimbal assembly, to which the abrasive member is attached, permitting the abrasive member to move independently in at least pitch and roll, the preload structure biasing the second surface of the abrasive member toward the substrate; and 
   fluid bearing features on the second surface of the abrasive member generate lift forces during motion of the abrasive article relative to the substrate.   
     
     
         10 . The abrasive article of  claim 9  wherein the bearing structure is a hydrostatic bearing structure. 
     
     
         11 . The abrasive article of  claim 9  wherein the bearing structure is a hydrodynamic bearing structure. 
     
     
         12 . The abrasive article of  claim 9  wherein the abrasive features comprise abrasives attached to the fluid bearing features of the abrasive members. 
     
     
         13 . The abrasive article of  claim 9  wherein the plurality of abrasive members comprises an interconnected array of molded abrasive members. 
     
     
         14 . The abrasive article of  claim 9  wherein the abrasive members comprise a cylindrically shaped bearing surface. 
     
     
         15 . The abrasive article of  claim 9  wherein the abrasive members comprise a grooved bearing surface. 
     
     
         16 . The abrasive article of  claim 9  wherein the abrasive features comprise abrasive material attached to the second surface of the abrasive members, a slurry of free abrasive particles located at the interface of the second surface and the substrate, or a combination thereof. 
     
     
         17 . An abrasive article for polishing a substrate, the abrasive article comprising:
 a plurality of interconnected abrasive members wherein at least some of the plurality of interconnected abrasive members comprise at least one bearing structure, the abrasive members including a first surface and a second surface; and   an abrasive feature located on the second surface of the abrasive members, the abrasive feature applying a cutting or a contact force to the substrate during motion of the abrasive article relative to the substrate.   
     
     
         18 . The abrasive article of  claim 17  wherein the bearing structure is a hydrostatic bearing structure. 
     
     
         19 . The abrasive article of  claim 17  wherein the bearing structure is a hydrodynamic bearing structure. 
     
     
         20 . The abrasive article of  claim 17  wherein the abrasive feature comprise abrasives attached to the abrasive feature of the abrasive member. 
     
     
         21 . The abrasive article of  claim 17  wherein the plurality of interconnected abrasive members comprise an interconnected array of molded abrasive members. 
     
     
         22 . The abrasive article of  claim 17  wherein the abrasive members comprise a cylindrically shaped second surface. 
     
     
         23 . The abrasive article of  claim 17  wherein the abrasive members comprise a second surface having a groove therein. 
     
     
         24 . The abrasive article of  claim 17  wherein the abrasive feature comprises one or more of an abrasive materials attached to the second surface of the abrasive members, the abrasive article further comprising a slurry of free abrasive particles located at the interface of the second surface and the substrate. 
     
     
         25 . An apparatus for polishing a surface of a substrate, the apparatus comprising:
 a gimbal structure including an array of gimbal assemblies; and   a preload mechanism that biases the array of gimball assemblies toward the substrate.   
     
     
         26 . The apparatus of  claim 25  further comprising a plurality of gas conduits adapted to deliver pressurized gas to one or more pressure ports positioned opposite the substrate.