Mold resin-sealed power semiconductor device having insulating resin layer fixed on bottom surface of heat sink and metal layer on the resin layer

摘要

An insulating sheet consisting of a metal layer and an unhardened insulating resin layer is formed. The insulating resin layer contains a filler having grains of, e.g., scale-like shape and has thixotropy, and its outer size is larger than that of a bottom surface of a metal plate. The insulating sheet is disposed on a bottom surface of a cavity of a mold die and the metal plate is disposed on an upper surface of the insulating resin layer. On a main surface of the metal plate, a power semiconductor chip connected to a frame and another frame through a wire is mounted. The cavity is fully filled with a liquid mold resin in this state. After that, the insulating resin layer is hardened at the same timing as the hardening of the mold resin, and the insulating resin and the metal plate are fixed to each other. An interface between the insulating resin layer and the metal plate is included in the upper surface of the insulating resin layer.