| 摘要 |
<p>PURPOSE:To provide a highly reliable power transistor by mounting a semiconductor wafer through an electric insulating material provided with slits and having high heat conductivity at a heat sink. CONSTITUTION:Slits 360 are provided on an insulating plate 320 by a press or the like and a metallized layer 340 is formed on the portion excluding the slits 360 of the insulating plate 320 to thereby form an electric insulating material 300 having high heat conductivity. The chip 100 of a power transistor is soldered with solder to a molybdenum plate 120, and the plate 120 is brazed with silver brazing filler 220 to a heat sink 140 of copper. The insulating plate 300 is secured via solders 240, 260 between the heat sinks 140 and 160. Since gas forming voids in the solder is discharged through the slits provided on the insulating plate 300 externally at this soldering time, less voids are produced. Accordingly, the heat on the chip 100 is efficiently dissipated to thereby prevent the power transistor from breaking so as to improve the reliability thereof.</p> |
