| abstract |
A problem to be solved by the present invention is to devise a melting process of a solder plating and to arrange the center of the Cu ball to be a core layer of the bump electrode on the electrode pad in the horizontal cross section with a high reproducibility in the center of the outer periphery of the coated solder . And a bump electrode 30 bonded to the electrode pad 12 and having a solder 14 applied to the Cu ball 13 serving as a core layer. The bump electrode 30 is formed on the bump electrode 30 after the flux 16 is applied, Heating of the substrate 11 on which the electrode pad 12 and the Cu nucleus ball are mounted in the melting process which is mounted on the electrode pad 12 and in which the electrode pad 12 and the Cu nucleus ball are heated to melt the solder plating 24, Rate is set in a range of not less than 0.01 [占 폚 / sec] and not more than 0.3 [占 폚 / sec]. |