Process and system for providing electrochemical processing solution with reduced oxygen and gas content

Abstract

The present invention provides a method and system for electrochemically processing a workpiece surface using a process solution that is degassed and deoxygenated. A deoxygenation step of the process solution substantially removes dissolved oxygen from the process solution by utilizing a treatment gas. In a following degassing step, remaining oxygen, the treatment gas and other gases are removed from the process solution by degassing the deoxygenated solution in a degasser. After degassing, the process solution is used to electrochemically process the workpiece surface.

I claim:  
     
         1 . A method of electrochemically processing a conductive surface of a workpiece using a process solution, comprising the steps of: 
 deoxygenating the process solution to substantially remove oxygen from the process solution;    degassing the process solution, after deoxygenating, to remove gases; and    electrochemically processing the surface of the workpiece with the process solution that is deoxygenated and degassed.    
     
     
         2 . The method of  claim 1 , wherein the step of deoxygenating comprises introducing a treatment gas into the process solution.  
     
     
         3 . The method of  claim 2 , wherein the step of degassing removes the treatment gas along with gases from the process solution.  
     
     
         4 . The method of  claim 3 , wherein the degassing step further reduces the amount of remaining oxygen.  
     
     
         5 . The method of  claim 1 , wherein the step of processing comprises electrochemical deposition.  
     
     
         6 . The method of  claim 5 , wherein the electrochemical deposition comprises copper electrodeposition.  
     
     
         7 . A system for removing gasses from a process solution that is used to process a workpiece surface, comprising: 
 a holding tank for holding the process solution;    a deoxygenator for receiving the process solution from the holding tank to substantially reduce oxygen content in the process solution; and    a degasser for receiving the process solution, which is deoxygenated, from the deoxygenator to remove substantially all gases from the process solution.    
     
     
         8 . The system of  claim 7 , further comprising at least one processing unit for receiving the process solution from the degasser to process the workpiece surface.  
     
     
         9 . The system of  claim 7 , wherein the deoxygenator treats the process solution with a treatment gas to reduce the oxygen content.  
     
     
         10 . The system of  claim 9 , wherein the treatment gas is nitrogen.  
     
     
         11 . The system of  claim 9 , wherein the degasser removes the treatment gas as it removes substantially all gases.  
     
     
         12 . The system of  claim 7 , further comprising the step of returning the process solution back to the holding tank after using the process solution to process the workpiece surface.  
     
     
         13 . The system of  claim 7 , further comprising a first line for flowing the process solution from the holding tank to the deoxygenator.  
     
     
         14 . The system of  claim 13 , further comprising a second line to flow the process solution from the degasser back to the holding tank.  
     
     
         15 . The system of  claim 14 , further comprising at least one processing unit for receiving the process solution from the holding tank to process the workpiece surface.  
     
     
         16 . The system of  claim 15 , further comprising a third line for flowing the process solution from the holding tank to the at least one processing unit.  
     
     
         17 . The system of  claim 16 , further comprising a fourth line for flowing the process solution from the at least one processing unit to the holding tank.  
     
     
         18 . The system of  claim 8 , wherein the at least one processing unit is an electrodeposition unit.