Pad with shallow cells for electrochemical mechanical processing

Abstract

The present invention generally provides a polishing article that is easy to clean, reduces debris and by product accumulation and reduces amount of polishing solution needed.

1 . A pad assembly for processing. a substrate, comprising:
 a first conductive layer having an upper surface adapted to contact the substrate;   a second conductive layer disposed below the first conductive layer with an insulative layer therebetween; and   a compressive layer disposed below the second conductive layer opposite the first conductive layer,   wherein a plurality of recesses are formed above the second conductive layer.   
     
     
         2 . The pad assembly of  claim 1 , further comprising a conductive carrier coupled to and disposed below the first conductive layer. 
     
     
         3 . The pad assembly of  claim 2 , wherein the conductive carrier is made of a fabric coated with conductive material. 
     
     
         4 . The pad assembly of  claim 1 , wherein the first conductive layer comprises a plurality of discrete members separated by the plurality of recesses, and the second conductive layer defines a bottom wall of the plurality of recesses. 
     
     
         5 . The pad assembly of  claim 4 , wherein the second conductive layer has a continuous body. 
     
     
         6 . The pad assembly of  claim 4 , wherein compressive layer is not in fluid communication with the plurality of recesses. 
     
     
         7 . The pad assembly of  claim 1 , wherein the plurality of recesses define an open area of between about 10 to about 90 percent of the pad assembly. 
     
     
         8 . The pad assembly of  claim 1 , further comprising a pad base disposed below the compressive layer. 
     
     
         9 . The pad assembly of  claim 1 , wherein the first conductive layer comprises a plurality of removal particles. 
     
     
         10 . The pad assembly of  claim 9 , wherein the plurality of removal particles are abrasive particles. 
     
     
         11 . The pad assembly of  claim 1 , further comprises binding layers between the first conductive layer and the insulative layer, between the insulative layer and the second conductive layer, and between the second conductive layer and the compressive layer. 
     
     
         12 . The pad assembly of  claim 1 , wherein the second conductive layer comprises a copper mesh. 
     
     
         13 . A pad assembly for processing a substrate, comprising:
 a first electrode;   a compressive layer disposed on one side of the first electrode; and   a plurality of discrete members coupled to the first electrode opposite the compressive layer, wherein the plurality of discrete members and the first electrode define a plurality of recesses configured to retain a processing solution therein, each of the plurality of discrete members comprises a conductive layer adapted to contact the substrate and an insulative layer disposed between the first electrode and the conductive layer.   
     
     
         14 . The pad assembly of  claim 13 , wherein the conductive layer comprises:
 a conductive composite having a processing surface configured to contact the substrate; and   a conductive carrier coupled to the conductive composite opposite the processing surface.   
     
     
         15 . The pad assembly of  claim 14 , wherein the conductive carrier comprises a fabric coated with a conductive material. 
     
     
         16 . The pad assembly of  claim 13 , wherein the conductive layer comprises a plurality of conductive particles, a conductive foil or a conductive foam. 
     
     
         17 . The pad assembly of  claim 13 , wherein the conductive layer comprises abrasive particles. 
     
     
         18 . The pad assembly of  claim 13 , further comprising a pad base coupled to the compressive layer. 
     
     
         19 . The pad assembly of  claim 13 , wherein the compressive layer is not in fluid communication with the plurality of recesses. 
     
     
         20 . The pad assembly of  claim 13 , wherein the first electrode comprises a copper mesh or copper mesh.