Patent ID: 6527934
Filing Date: 2003-03-04
Classification: C25D

Abstract:
A process for electrolytically depositing copper onto a workpiece utilizing an electroplating apparatus including a power source and a plating vessel, comprising the steps of:providing a copper generation vessel; generating a copper plating solution of CuSO4 by adding solid-state copper and H2SO4 and H2O2 to the copper generation vessel; continuously circulating the copper plating solution between the copper generation vessel and the plating vessel; providing an insoluble, dimensionally stable anode in the plating vessel in contact with the plating solution; immersing the workpiece in the plating solution in the plating vessel in close proximity to the anode; passing an electric current through the plating solution between the anode and the workpiece to be plated so that the workpiece acts as a cathode in an electrolytic circuit and copper ions are electrolytically deposited as copper onto the workpiece; positioning the workpiece in the plating solution in the plating vessel so that all surfaces to be plated are exposed to the anode surface; and maintaining the H2O2 at a concentration of about 0.0045 ounces per gallon or less in the plating solution in the plating vessel.