Electrolytic processing apparatus and method

Abstract

The present invention provides an electrolytic processing apparatus which can suppress the growth of a gas, which is inevitably generated during electrochemical processing, into bubbles thereby effectively preventing the formation of pits in a surface of a workpiece. The electrolytic processing apparatus includes an electrode section ( 44 ) including processing electrodes ( 76 ) and feeding electrodes ( 78 ) both having a diameter of not more than 1 mm, a substrate holder ( 42 ) for holding a workpiece (W), a power source ( 46 ) for applying a voltage between the processing electrodes and the feeding electrodes, a fluid supply section ( 72 ) for supplying a fluid between the electrode section and the workpiece, and a drive section ( 56, 62 ) for moving the electrode section and the workpiece relative to each other in such a manner that the processing electrodes pass every point in a processing surface of the workpiece.

1 . An electrolytic processing apparatus, comprising: 
 an electrode section including a plurality of processing electrodes and feeding electrodes both having a diameter of not more than 1 mm, said processing electrodes being electrically isolated from said feeding electrodes;    a substrate holder for holding a workpiece and bringing the workpiece close to the electrode section;    a power source for applying a voltage between the processing electrodes and the feeding electrodes;    a fluid supply section for supplying a fluid between the electrode section and the workpiece which is held by the substrate holder and has been brought close to the electrode section; and    a drive section for moving the electrode section and the workpiece relative to each other in such a manner that a plurality of said processing electrodes pass every point in a processing surface of the workpiece held by the substrate holder.    
   
   
       2 . The electrolytic processing apparatus according to  claim 1 , wherein the distance between each processing electrode and each feeding electrode, adjacent to each other, is at least equal to the distance between the workpiece and the processing electrodes or the feeding electrodes.  
   
   
       3 . The electrolytic processing apparatus according to  claim 1 , wherein an ion exchanger is disposed between the workpiece and at least one of the processing electrodes and the feeding electrodes.  
   
   
       4 . The electrolytic processing apparatus according to  claim 1 , wherein an ion exchanger which integrally covers the processing electrodes and the feeding electrodes is disposed between the workpiece and the processing and feeding electrodes.  
   
   
       5 . The electrolytic processing apparatus according to  claim 3 , wherein the ion exchanger extends between a supply shaft and a take-up shaft, and is taken up sequentially.  
   
   
       6 . The electrolytic processing apparatus according to  claim 3 , further comprising an ion exchanger regeneration section for regenerating the ion exchanger.  
   
   
       7 . The electrolytic processing apparatus according to  claim 1 , wherein the fluid supply section comprises a fluid supply passage penetrating the electrode section.  
   
   
       8 . The electrolytic processing apparatus according to  claim 1 , wherein the electrode section comprises an electrode plate made of a liquid-permeable porous insulating material.  
   
   
       9 . The electrolytic processing apparatus according to  claim 1 , wherein said fluid is pure water, ultrapure water, a fluid having an electric conductivity of not more than 500 μS/cm, or an electrolytic solution.  
   
   
       10 . An electrolytic processing method, comprising: 
 opposing a workpiece to an electrode section including a plurality of processing electrodes and feeding electrodes both having a diameter of not more than 1 mm, said processing electrodes being electrically isolated from said feeding electrodes;    supplying a liquid between the electrode section and the workpiece; and    moving the electrode section and the workpiece relative to each other in such a manner that a plurality of said processing electrodes pass every point in a processing surface of the workpiece held by the substrate holder, while applying a voltage between the processing electrodes and the feeding electrodes.    
   
   
       11 . The electrolytic processing method according to  claim 10 , wherein the distance between each processing electrode and each feeding electrode, adjacent to each other, is at least equal to the distance between the workpiece and the processing electrodes or the feeding electrodes.  
   
   
       12 . The electrolytic processing method according to  claim 10 , wherein an ion exchanger is disposed between the workpiece and at least one of the processing electrodes and the feeding electrodes.  
   
   
       13 . The electrolytic processing method according to  claim 10 , wherein an ion exchanger which integrally covers the processing electrodes and the feeding electrodes is disposed between the workpiece and the processing and feeding electrodes.  
   
   
       14 . The electrolytic processing method according to  claim 12 , wherein the ion exchanger extends between a supply shaft and a take-up shaft, and is taken up sequentially.  
   
   
       15 . The electrolytic processing method according to  claim 12 , further comprising an ion exchanger regeneration section for regenerating the ion exchanger.  
   
   
       16 . The electrolytic processing method according to  claim 10 , wherein the fluid supply section comprises a fluid supply passage penetrating the electrode section.  
   
   
       17 . The electrolytic processing method according to  claim 10 , wherein the electrode section comprises an electrode plate made of a liquid-permeable porous insulating material.  
   
   
       18 . The electrolytic processing method according to  claim 10 , wherein said fluid is pure water, ultrapure water, a fluid having an electric conductivity of not more than 500 μS/cm, or an electrolytic solution.  
   
   
       19 . The electrolytic processing apparatus according to  claim 4 , wherein the ion exchanger extends between a supply shaft and a take-up shaft, and is taken up sequentially.  
   
   
       20 . The electrolytic processing apparatus according to  claim 4 , further comprising an ion exchanger regeneration section for regenerating the ion exchanger.