| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a bump forming method, which can form the large size bumps having good configuration on the electrode of an electronic part, such as a substrate and a chip. SOLUTION: Cream solder 3 is applied on electrodes 2 of a substrate 1. Then, after the cream solder 3 is diffused and solidified by a reflow means and a core 3 of a bump is formed, cream solder 3' is applied so as to cover the core 3 by a screen printing means. Then, the cream solder 3' is heated, fused and solidified by the reflow means. In this case, the wettability of the core 3 is large, the core 3 has the spherical surface, and the surface area is large. Therefore, the fused cream solder 3' is surely stuck to the entire surface, and the flowing to sideward can be suppressed. The neighboring cream solder 3' are connected together, and the generation of bridges can be prevented.</p> |
