Apertured conditioning brush for chemical mechanical planarization systems

Abstract

An apparatus for conditioning the polishing pad of a chemical mechanical planarization (CMP) system including an apertured conditioning disk that is formed to support a plurality of brush bristles in any desired configuration. The bristles are utilized to lift out debris and contaminants that have been lodged within the deep pores of polishing pads, particularly “soft” polishing pads (or polishing felts) that include relatively deep pores. The apertures in the conditioning disk are used to allow for the efficient evacuation of the effluent created during the conditioning process. The apertures may also be used to introduce conditioning fluids as the bristles are brushing the surface to assist in the conditioning process. The utilization of the apertures to evacuate the effluent (via an attached vacuum source) overcomes problems associated with the prior art by immediately removing the dislodged material from the pad surface before it has an opportunity to be re-incorporated into the polishing pad.

1 . An apparatus for conditioning a polishing pad utilized in a chemical mechanical planarization (CMP) system, the apparatus comprising 
 a conditioner head housing including an inlet port for introducing conditioning fluids onto the polishing pad and an outlet port for evacuating conditioning effluent from a conditioned area of said polishing pad; and    a conditioning disk disposed within the housing so as to contact a top major surface of the polishing pad surface during conditioning, the conditioning disk comprising 
 a brush for sweeping the top major surface of the polishing pad and dislodging debris therefrom, and  
 a plurality of apertures for dispensing conditioning fluids to, and evacuating conditioning effluent from, the polishing pad.  
   
   
   
       2 . An apparatus as defined in  claim 1  wherein the brush comprises a plurality of bristles.  
   
   
       3 . An apparatus as defined in  claim 1  wherein the conditioning disk comprises an abrasive material.  
   
   
       4 . An apparatus as defined in  claim 2  wherein the plurality of bristles comprises an inert material.  
   
   
       5 . An apparatus as defined in  claim 4  wherein the inert material comprises nylon.  
   
   
       6 . An apparatus as defined in  claim 2  wherein the plurality of bristles comprises a composite abrasive-filled material.  
   
   
       7 . An apparatus as defined in  claim 2  wherein the plurality of bristles is disposed in a series of nested V-patterns across the conditioning disk, with the apertures disposed therebetween.  
   
   
       8 . An apparatus as defined in  claim 2  wherein the plurality of bristles is disposed in a series of concentric circles across the conditioning disk.  
   
   
       9 . An apparatus as defined in  claim 2  wherein the plurality of bristles is disposed in a plurality of spiral arms emanating from a central region of the conditioning disk.  
   
   
       10 . An apparatus as defined in  claim 2  wherein the plurality of bristles stand off a predetermined distance below the conditioner head housing so as to allow for the bristles to enter the polishing pad material without interrupting the evacuation of effluent therefrom.  
   
   
       11 . An apparatus as defined in  claim 1  wherein the conditioning disk further comprises a hex key alignment structure for providing aligned attachment between the conditioning disk and the conditioner head housing, providing alignment between the plurality of apertures of said conditioning disk and the inlet and outlet ports of said conditioner head housing.  
   
   
       12 . A conditioning disk for use in dressing a polishing pad within a chemical mechanical planarization (CMP) apparatus, the conditioning disk comprising a plurality of apertures for dispensing conditioning fluids to, and evacuating conditioning effluent from, the polishing pad surface; and 
 a brush for sweeping across the fibrous polishing pad and dislodging debris therefrom.    
   
   
       13 . A conditioning disk as defined in  claim 12  wherein the brush comprises a plurality of bristles.  
   
   
       14 . A conditioning disk as defined in  claim 12  wherein the disk comprises an abrasive material suitable for dressing the polishing pad.  
   
   
       15 . A conditioning disk as defined in  claim 13  wherein the plurality of bristles comprises an inert material.  
   
   
       16 . A conditioning disk as defined in  claim 15  where the inert material comprises nylon.  
   
   
       17 . A conditioning disk as defined in  claim 13  wherein the plurality of bristles comprises a composite abrasive-filled material.  
   
   
       18 . A conditioning disk as defined in  claim 13  wherein the plurality of bristles is disposed in a series of nested V-patterns across the conditioning disk, with the plurality of apertures disposed therebetween.  
   
   
       19 . A conditioning disk as defined in  claim 13  wherein the plurality of bristles is disposed in a series of concentric circles across the conditioning disk.  
   
   
       20 . A conditioning disk as defined in  claim 13  wherein the plurality of bristles is disposed in a plurality of spiral arms emanating from a central region of the conditioning disk.  
   
   
       21 . A method of conditioning a polishing pad utilized in a chemical mechanical planarization system, the method comprising the steps of: 
 presenting an apertured conditioning brush against a top major surface of the polishing pad, the apertured conditioning brush comprising a plurality of bristles and a plurality of apertures;    providing a downforce on the apertured conditioning brush sufficient to push the plurality of bristles into the pores of the polishing pad;    moving said apertured conditioning brush across the surface of said polishing pad such that the plurality of bristles dislodge accumulated debris from the pores; and    applying a vacuum force sufficient to evacuate the dislodged accumulated debris through the plurality of apertures and away from the chemical mechanical planarization system.    
   
   
       22 . The method as defined in  claim 21  wherein the method further comprises the step of 
 dispensing processing fluids onto the surface of the polishing pad as the apertured conditioning brush is moved across the surface of the polishing pad.    
   
   
       23 . The method as defined in  claim 21  wherein the applied downforce and the vacuum force are controlled so as to allow for the plurality of bristles to engage the pores of the polishing pad without interrupting the vacuum-controlled evacuation of the dislodged debris therefrom.