| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To maintain radiation characteristics of a semiconductor device and to suppress the destruction etc., of a joining layer due to warping and thermal fatigue of a substrate after joining of a ceramic substrate and a metallic heat sink by effectively lowering the thermal expansion coefficient of a solder material without impairing the thermal conductivity and joining characteristics, etc., of the non-lead-based solder. <P>SOLUTION: The solder material contains the non-lead-based solder and particles having the thermal expansion coefficient ranging from 0 to -10x10<SP>-6</SP>/°C at room temperature. In the semiconductor device 1, the metallic heat sink 2 and the ceramic circuit board 3 are joined by such non-lead-base solder. A power semiconductor element 8 and the like are joined to and mounted on the ceramic circuit board 3. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
