| 摘要 |
PROBLEM TO BE SOLVED: To provide a technique for soldering well without increasing the adverse effect due to surplus soldering material, in the soldering of a heat dissipation device having a plurality of joints, where there is a difference in the difficulty of solderability, e.g., between a metal and ceramics.SOLUTION: A circuit layer 12 for mounting an electronic component 14 is laminated on one side of an insulation layer 11, and a heat sink 20 is stacked on the other side thereof over an aluminum layer 13, before being integrated as a heat dissipation device 1. The insulation layer 11 and aluminum layer 13 are joined by a first soldering material 41, the aluminum layer 13 and the heat sink 20 are joined by a second soldering material 42, and the solidus temperature X°C of the first soldering material 41 and the solidus temperature Y°C of the second soldering material 42 satisfy a relation X<Y. A relation of 0.5<Y-X<30 is also satisfied. The solidus temperature X of the first soldering material is 500-565°C, and the solidus temperature Y of the second soldering material is 520-577°C. |
