Electrolytic plating method and device for a wiring board

Abstract

A plating bath which accommodates an insoluble node and a printed-circuit board, and a copper dissolved bath which supplies copper ions are arranged. The insoluble anode Is arranged as opposed to the printed-circuit board being a cathode, and a forward/reverse current is applied between both of the electrodes. Iron ions are added to a plating solution.

1 - 6 . (canceled)  
   
   
       7 . An electrolytic plating device, comprising; 
 a wiring board with microvia holes, each having a bottom made of copper foil provided on a surface of the wiring board as an electrode;    an insoluble electrode, which is an electrode opposed to the wiring board;    a metal plating solution containing iron ions of at least 0.1 gram/liter;    a power source for performing electrolytic plating by applying a forward/reverse current between the wiring board and said insoluble electrode; and    a stirring unit stirring said metal plating solution to make the solution flow in parallel to the surface to be plated of said wiring board so that the microvia holes having the copper foil at the bottom, which are formed on the surface of said wiring board, may be filled up with said metal plating.    
   
   
       8 . The electrolytic plating device according to  claim 7 , wherein: 
 the metal plating solution is comprised of copper plating solution; and    the stirring unit adjusts a flow rate of the copper plating solution to a level at which copper deposition speeds both on the surface and inside microvia holes of the wiring board are optimum.    
   
   
       9 . The electrolytic plating device according to  claim 8 , wherein 
 the string unit adjusts the flow rate of the copper plating solution to bring the iron ion amount present near to wiring board surface to a level at which all the microvia holes are almost fully filled and the plating layer thickness on the wiring board surface becomes optimum.    
   
   
       10 . The electrolytic plating device according to  claim 9 , further comprising: 
 a plating bath accommodating the insoluble electrode and the wiring board; and    a copper dissolved bath supplying copper ions to said plating bath, wherein    said stirring unit circulates a solution within the copper dissolved bath and the plating solution within the plating bath.    
   
   
       11 . The electrolytic plating device according to  claim 7 , wherein: 
 said insoluble electrode is implemented by a multi-aperture electrode; and    said plating solution is implemented by a copper plating solution.