| 摘要 |
PURPOSE:To enable the self heat-generation of a power transistor to be well- dissipated by a method wherein a hybrid thick film IC is formed directly on a substrate having thermal conductivity and electric insulation, and the substrate is operated as a heat sink. CONSTITUTION:The substrate 17 is made of a material having thermal conductivity and electric insulation, such as a sintered body of silicon carbide. The hybrid thick film IC composed of a power transistor 9, a small-signal transistor 10 and the like is formed on this substrate 17, and a lead frame 8 to connect the IC to the outside is fixed to the edge of the surface of the substrate 17. This manner enables the self heat-generation of the power transistor 9 to be released by direct conduction to the substrate 17; therefore, the cooling efficiency increases. As a result, the thermal breakdown of the power transistor 9 can be prevented. |
