Nonwoven polishing pads for chemical mechanical polishing

Abstract

A polishing article and its use as a polishing article for various substrates, especially for polishing a semiconductor wafer. The article is comprised of a mesh of splittable intermingled fibers and a binder material holding the fibers in the mesh. The fibers and binder material provide the polishing pad with an absorptive property that maintains the slurry chemistry and particles near the surface for effective polishing.

1 . An article comprising: 
 a nonwoven polishing pad including a mesh of polymeric fibers comprising a plurality of composite intermingled fibers, wherein the mesh of polymeric fibers result from being spunbonded and spunlaced.    
     
     
         2 . The article of  claim 1 , wherein the pad comprises a plurality of layers of fabric, the plurality of layers being stacked one upon another.  
     
     
         3 . The article of  claim 2 , wherein the fibers of one layer are intermingled with the fibers of a different layer by needle punching.  
     
     
         4 . The article of  claim 3 , wherein the pad is a substantially thick mat suitable for a chemical mechanical polishing pad.  
     
     
         5 . The article of  claim 1 , wherein the pad comprises a transparent window.  
     
     
         6 . The article of  claim 5 , wherein the pad comprises a polymer and wherein the window results from melting a portion of the pad to form the window.  
     
     
         7 . The article of  claim 1 , wherein the pad comprises a resin matrix disposed within the pad.  
     
     
         8 . The article of  claim 7 , wherein the resin matrix of the pad is disposed within the pad by saturation.  
     
     
         9 . The article of  claim 8 , wherein the resin matrix is disposed within the pad by at least one of absorption, immersion, coating, impregnation, roller disposition, spray disposition, and stir casting processes.  
     
     
         10 . An article comprising: 
 a nonwoven polishing pad including a mesh of polymeric fibers comprising a plurality of composite intermingled fibers, wherein the mesh of polymeric fibers result from being spunbonded and spunlaced and wherein the plurality of composite fibers include a plurality of splittable multicomponent fibers    
     
     
         11 . The article of  claim 10 , wherein a portion of the plurality of splittable multicomponent fibers comprises a low-melt polymer.  
     
     
         12 . The article of  claim 10 , further comprising a web of the composite intermingled fibers resulting from being spunlaced and spunbonded.  
     
     
         13 . The article of  claim 10 , wherein the pad comprises a plurality of layers of fabric, wherein the fibers of one layer are intermingled with the fibers of a different layer by needle punching.  
     
     
         14 . The article of  claim 10 , wherein the pad comprises a transparent window.  
     
     
         15 . The article of  claim 14 , wherein the pad comprises a polymer and wherein the window results from melting a portion of the pad.  
     
     
         16 . The article of  claim 10 , wherein the pad comprises a resin matrix disposed within the pad.  
     
     
         17 . The article of  claim 16 , wherein the resin matrix of the pad is disposed within the pad by saturation.  
     
     
         18 . The article of  claim 17 , wherein the resin matrix is disposed within the pad by at least one of absorption, immersion, coating, impregnation, roller disposition, spray disposition, and stir casting processes.  
     
     
         19 . A method of manufacturing a nonwoven polishing article with a mesh of polymeric fibers comprising: 
 providing a plurality of nonwoven fabric layers, each layer having a spunbonded and spunlaced construction of multicomponent fibers;    intermingling the fibers of at least one of the plurality of layers with another of the plurality of layers to form a mat;    impregnating the mat with a resin to form an impregnated mat; and    curing the impregnated mat to form a pad.    
     
     
         20 . The method of  claim 19 , wherein the intermingling step comprises needlepunching.  
     
     
         21 . The method of  claim 19 , wherein a portion of the fibers of a layer comprise a low melt polymer capable of being thermally bonded within the matrices of the layer.  
     
     
         22 . The method of  claim 21 , further comprising the step of thermally bonding the portion of the fibers by hotpressing.  
     
     
         23 . The method of  claim 19 , further comprising the step of hotpressing the plurality of layers.  
     
     
         24 . The method of  claim 19 , further comprising the step of heating a portion of the pad to form an at least partially transparent window.  
     
     
         25 . The method of  claim 24 , further comprising the step of attaching a backing to the pad.  
     
     
         26 . The method of  claim 25 , wherein the attaching step comprises attaching the backing on the pad with a hook and loop structure.  
     
     
         27 . The method of  claim 19 , further comprising the step of forming a surface texture on a surface of the pad by at least one of hot-pressing, molding, calendaring, grinding, machining, or embossing with a roller.  
     
     
         28 . The method of  claim 19 , further comprising the step of applying a hydrophobic layer to the back surface of the pad, wherein the pad includes a polishing surface and a back surface.  
     
     
         29 . The method of  claim 19 , further comprising the step of applying a double sided adhesive layer to the back surface of the pad, wherein the pad includes a polishing surface and back surface.