Method for storage of a metal ion supply source in a plating equipment
To avoid change in plating performance, even where operation of the plating equipment is interrupted, the properties of the plating solution need to be preserved. For plating equipment having an insoluble anode, add a reservoir ( 7 ) for storing a replacement solution to the tank ( 4 ) having a metal ion supply source (copper ball ( 5 )) and, upon termination of the plating operation, the entire plating solution is discharged from the tank ( 4 ) containing the metal ion supply source, while the solution for replacement is transferred from the reservoir ( 7 ) to the empty tank having a metal ion supply source, and immediately prior to the resumption of the plating operation transfer the solution for replacement back to the reservoir ( 7 ) and return the plating solution to the tank ( 4 ) containing the metal ion supply source.
1 . A method for preventing deterioration of a plating solution when the operation of the plating equipment is interrupted, comprising the steps of providing a reservoir containing a solution causing no deterioration of the metal ion supply source as a replacement solution, and replacing at least part of the plating solution with said replacement solution when the plating operation is stopped.
2 . The method for preventing deterioration of a plating solution according to claim 1 , wherein in the plating equipment having an insoluble anode, a tank containing the metal ion supply source is provided with said reservoir, upon completion of the plating operation the entire plating solution is discharged from the tank containing the metal ion supply source, the replacement solution is transferred from the reservoir into the emptied tank containing the metal ion supply source, and when the plating operation is restarted, the replacement solution is returned into the reservoir and the plating solution is thereafter returned into the tank containing the metal ion supply source.
3 . The method for preventing deterioration of a plating solution according to claim 1 , wherein in the plating equipment having a soluble anode, a plating tank is provided with said reservoir and a plating solution storage tank, upon completion of the plating operation the plating solution is transferred from the plating tank into the plating solution storage tank and the replacement solution is transferred from the reservoir into the emptied plating tank, and when the plating operation is restarted, the replacement solution is returned into the reservoir and the plating solution is thereafter returned into the plating tank.
4 . The method for preventing deterioration of a plating solution according to any of claims 1 - 3 , wherein said replacement solution is a plating solution containing no brightener that undergoes a decomposing reaction when the plating operation is stopped.
5 . The method for preventing deterioration of a plating solution according to any of claims 1 - 4 , wherein said plating is copper plating.
6 . The method for preventing deterioration of a plating solution according to claim 4 , wherein said replacement solution is a sulfuric acid solution.