Apparatus for avoiding particle accumulation in electrochemical processing

Abstract

Systems and methods to remove or lessen the size of metal particles that have formed on, and to limit the rate at which metal particles form or grow on, workpiece surface influencing devices used during electrodeposition are presented. According to an exemplary method, the workpiece surface influencing device is occasionally placed in contact with a conditioning substrate coated with an inert material, and the bias applied to the electrodeposition system is reversed. According to another exemplary method, the workpiece surface influencing device is conditioned using mechanical contact members, such as brushes, and conditioning of the workpiece surface influencing device occurs, for example, through physical brushing of the workpiece surface influencing device with the brushes. According to a further exemplary method, the workpiece surface influencing device is rotated in different direction during electrodeposition.

1 . A processing apparatus for electrochemical mechanical processing of a workpiece using a solution comprising: 
 an electrochemical mechanical processing system adapted to operate on the workpiece, the system including an electrode, a holder adapted to hold the workpiece, a terminal adapted to make electrical contact with the workpiece, and a workpiece surface influencing device, wherein the electrochemical mechanical processing system is adapted to operate upon the workpiece using the solution, with the workpiece surface influencing device being disposed in proximity to the workpiece for a period of time during the electrochemical mechanical processing, the electrochemical mechanical processing also resulting in accumulation of particles onto the workpiece surface influencing device; and    a system adapted to operate on the workpiece surface influencing device and thereby result in one of the number of accumulated particles being reduced and the size of the accumulated particles being reduced.    
   
   
       2 . The apparatus according to  claim 1 , wherein the system is attached to the holder and adapted to permit both the conditioning of the workpiece surface influencing device and the electrochemical mechanical processing on the workpiece to occur simultaneously.  
   
   
       3 . The apparatus according the  claim 1 , wherein electrochemical mechanical processing comprises an electrochemical mechanical deposition process.  
   
   
       4 . The apparatus according to  claim 1 , wherein electrochemical mechanical processing comprises an electrochemical mechanical polishing process.  
   
   
       5 . The apparatus according to  claim 1 , wherein the system is adapted to condition the workpiece surface influencing device by at least one of electrochemically etching the accumulated particles and mechanically contacting the accumulated particles.  
   
   
       6 . The apparatus according to  claim 1 , wherein the particles are conductive particles.  
   
   
       7 . The apparatus according to  claim 1 , wherein the particles are non-conductive particles.  
   
   
       8 . The apparatus according to  claim 1 , wherein the system includes a conditioning substrate with a plurality of brushes thereon, the plurality of brushes adapted to mechanically contact the workpiece surface influencing device.  
   
   
       9 . The apparatus according to  claim 8 , wherein the conditioning substrate attaches to the holder upon removal of the workpiece from the holder.  
   
   
       10 . The apparatus according to  claim 1 , wherein the system includes a conditioning conductor layer that will not anodize in the solution, and the conditioning conductor layer is adapted to be electrically connected to a potential difference that will cause the one of the number of accumulated particles to be reduced and the size of the accumulated particles to be reduced.  
   
   
       11 . The apparatus according to  claim 10 , wherein the conditioning conductor layer attaches to the holder upon removal of the workpiece from the holder.  
   
   
       12 . The apparatus according to  claim 1 , wherein the system and the electrochemical mechanical processing system are located within a lower chamber of a vertically configured chamber system, the vertically configured chamber system also including an upper chamber that includes a cleaning system that cleans the workpiece and a moveable guard adapted to separate the lower chamber from the upper chamber when the upper chamber is being used.  
   
   
       13 . The apparatus according to  claim 12 , wherein the system includes a plurality of brushes attached to a conditioning substrate and a brush movement assembly, the brush movement assembly configured to move the plurality of brushes over the workpiece surface influencing device to operate on the workpiece surface influencing device.  
   
   
       14 . The apparatus according to  claim 13 , wherein the system is adapted to operate on the workpiece surface influencing device at the same time the cleaning system is adapted to operate upon the workpiece.  
   
   
       15 . The apparatus according to  claim 13 , wherein the plurality of brushes and the conditioning substrate have a conductive coating that will not anodize in the solution disposed within the lower chamber, the conditioning substrate adapted to be electrically connected to a potential difference that will cause the one of the number of accumulated particles to be reduced and the size of the accumulated particles to be reduced.  
   
   
       16 . The apparatus according to  claim 15 , wherein the system is adapted to operate on the workpiece surface influencing device at the same time the cleaning system is adapted to operate upon the workpiece.  
   
   
       17 . The apparatus according to  claim 15 , wherein the conductive coating is comprised of an inert conductor.  
   
   
       18 . The apparatus according to  claim 12 , wherein the system includes a conditioning conductor layer that will not anodize in the solution disposed within the lower chamber, the conditioning conductor layer adapted to be electrically connected to a potential difference that will cause the one of the number of accumulated particles to be reduced and the size of the accumulated particles to be reduced.  
   
   
       19 . The apparatus according to  claim 18 , wherein the conditioning conductor layer is comprised of an inert conductor.  
   
   
       20 . The apparatus according to  claim 12 , wherein the system is adapted to operate on the workpiece surface influencing device at the same time the cleaning system is adapted to operate upon the workpiece.  
   
   
       21 . The apparatus according to  claim 1 , wherein the electrochemical mechanical processing system is located within a lower chamber of a vertically configured chamber system, the vertically configured chamber system also including an upper chamber and a moveable guard adapted to separate the lower chamber from the upper chamber when the upper chamber is being used.  
   
   
       22 . The apparatus according to  claim 21 , further including a cleaning system that cleans the workpiece disposed in the upper chamber.  
   
   
       23 . The apparatus according to  claim 21 , wherein the holder is further adapted to hold the system when the holder is no longer holding the workpiece.  
   
   
       24 . The apparatus according to  claim 23 , wherein the system includes a plurality of brushes attached to a conditioning substrate, the plurality of brushes configured for relative movement with the workpiece surface influencing device to condition the workpiece surface influencing device.  
   
   
       25 . The apparatus according to  claim 24 , wherein the plurality of brushes and the conditioning substrate have a conductive coating that will not anodize in the solution disposed within the lower chamber, the conditioning substrate adapted to be electrically connected to a potential difference that will cause the one of the number of accumulated particles to be reduced and the size of the accumulated particles to be reduced.  
   
   
       26 . The apparatus according to  claim 25 , wherein the conductive coating is comprised of an inert conductor.  
   
   
       27 . The apparatus according to  claim 26 , wherein the system includes a conditioning conductor layer that will not anodize in the solution disposed within the lower chamber, the conditioning conductor layer adapted to be electrically connected to a potential difference that will cause the one of the number of accumulated particles to be reduced and the size of the accumulated particles to be reduced.  
   
   
       28 . The apparatus according to  claim 27 , wherein the conditioning conductor layer is comprised of an inert conductor.  
   
   
       29 . A system for processing a workpiece and removing particles on a workpiece surface influencing device, the workpiece surface influencing device being used in conjunction with a plating solution to process the workpiece, comprising: 
 a holder adapted to receive the workpiece and to move the workpiece proximate to the workpiece surface influencing device;    an apparatus adapted to deposit, via the plating solution, conductive material onto the workpiece using a first potential difference that is applied between an electrode and the workpiece with the workpiece surface influencing device in close proximity to the workpiece; and    a member having a conditioning conductor layer adapted to assist in removing at least a first portion of the particles that accumulate on the workpiece surface influencing device during the depositing of the conductive material using a second potential difference that is applied between the electrode and the conditioning conductor layer of the member, the second potential difference being of an opposite polarity to the first potential difference.    
   
   
       30 . The system according to  claim 29 , wherein the member further comprises a mechanical contact member to mechanically remove at least a second portion of the particles that accumulate on the workpiece surface influencing device.  
   
   
       31 . The system according to  claim 29 , wherein the holder is further adapted to hold the member when the holder is no longer holding the workpiece.  
   
   
       32 . A system for processing a workpiece and removing particles on a workpiece surface influencing device, the workpiece surface influencing device being used in conjunction with a plating solution to process the workpiece, comprising: 
 an apparatus adapted to deposit, via the plating solution and with the workpiece surface influencing device in close proximity to the workpiece, conductive material onto the workpiece in the presence of a first potential difference that is applied between an electrode and the workpiece;    a holder adapted to receive the workpiece, to move the workpiece in close proximity to the workpiece surface influencing device so that the depositing of the conductive material by the apparatus can take place, and to remove the workpiece from being in close proximity to the workpiece surface influencing device upon completion of the depositing by the apparatus; and    a member having at least one mechanical contact member and adapted to move against a top surface of the workpiece surface influencing device so that at least a portion of the particles that accumulate on the workpiece surface influencing device during the depositing of the conductive material are mechanically removed from the workpiece surface influencing device.    
   
   
       33 . The system according to  claim 32 , wherein the apparatus is further adapted to remove at least a second portion of the particles that accumulate on the workpiece surface influencing device during the depositing of the conductive material, and the at least one mechanical contact layer being comprised of an inert conductor so that the at least one mechanical contact layer conductor will not anodize in the plating solution.  
   
   
       34 . The apparatus according to  claim 32 , wherein the holder is further adapted to hold the member when the holder is no longer holding the workpiece.  
   
   
       35 . A system for processing a workpiece and removing particles on a workpiece surface influencing device, the workpiece surface influencing device being used in conjunction with a plating solution to process the workpiece, comprising: 
 a deposition apparatus positioned in a lower chamber for depositing conductive material from the plating solution onto the workpiece with the workpiece surface influencing device in close proximity to the workpiece; and    a member adapted to be positioned in the lower chamber and to remove at least a portion of the particles that accumulate on the workpiece surface influencing device during the depositing of the conductive material by the deposition apparatus; and    a holder adapted to position the workpiece in the lower chamber while the deposition apparatus is being used.    
   
   
       36 . The system according to  claim 35 , further comprising a cleaning system disposed in the upper chamber and wherein the upper and lower chamber are capable of being separated using a moveable guard.  
   
   
       37 . The system according to  claim 35 , wherein the member is adapted for relative movement with the workpiece surface influencing device so that the conductive particles are mechanically removed from the workpiece surface influencing device.  
   
   
       38 . The system according to  claim 35 , wherein the member is adapted to apply a potential difference between the member and the workpiece surface influencing device to assist in removing the particles from the workpiece surface influencing device.  
   
   
       39 . The system according to  claim 35 , wherein the holder is adapted to rotate about a first axis.  
   
   
       40 . The system according to  claim 39 , wherein the holder is further adapted to move side to side within the lower chamber.  
   
   
       41 . The system according to  claim 35 , wherein the deposition apparatus comprises an electrochemical mechanical deposition apparatus.  
   
   
       42 . The system according to  claim 35 , wherein the member comprises a brush member.  
   
   
       43 . The system according to  claim 42 , further comprising a brush assembly that moves the brush member connected thereto in a lateral direction and wherein the brush assembly is disposed in the lower chamber.  
   
   
       44 . The apparatus according to  claim 43  wherein the member is adapted to operate on the workpiece surface influencing device at the same time another system is operating upon the workpiece in the upper chamber.  
   
   
       45 . The system according to  claim 44 , wherein the brush assembly comprises a drive apparatus that moves the brush member in the lateral direction.