| 摘要 |
PROBLEM TO BE SOLVED: To arrange the center of a Cu ball, becoming the nucleus layer of a bump electrode on an electrode pad, at the center of the outer shell of a coated solder on the horizontal cross-section thereof, by contriving the melting process of solder plating.SOLUTION: A bump electrode 30 is bonded onto an electrode pad 12 by a solder 14 applied to a Cu ball 13 becoming a nucleus layer. The bump electrode 30 is coated with flux 16 and mounted on the electrode pad 12, and in the melting process for melting a solder plating 24 by heating the electrode pad 12 and Cu nucleus ball, the heating rate of a substrate 11 mounting the electrode pad 12 and Cu nucleus ball is set in a range of 0.01-0.3 (°C/sec). |
