BUMP ELECTRODE MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To prevent generation of voids due to remaining of air bubbles in the vicinity of an interface of an underlying metal layer to manufacture a bump electrode having high junction reliability.SOLUTION: A bump electrode manufacturing method comprises: a plating process of forming a solder plating layer on a surface of an underlying metal layer on a substrate by electrolytic plating; and a reflow treatment process of melting the solder plating layer after the plating process to form a solder bump on the underlying metal layer. The plating process includes: a high-speed plating process of plating the surface of the underlying metal layer at high speed to form a lower plating layer out of the solder plating layer; and a low-speed plating process of plating a surface of the lower plating layer after the high-speed plating process at low speed to form the other upper plating layer of the solder plating layer. In the high-speed plating process, electrolytic plating is performed at a current density not less than two times higher than a current density during the low-speed plating process and not more than 25 ASD to form the lower plating layer with a thickness of 1 μm and over.SELECTED DRAWING: Figure 2