Semiconductor power module

A semiconductor power module that is mounted on a front side of a case of a jacket provided with a flow path through which cooling fluid flows and that is cooled by the cooling fluid, the semiconductor power module comprising:

• a semiconductor device forming a switching circuit;
• a first electrode to which the semiconductor device is die-bonded;
• a second electrode connected with the semiconductor device;
• a heat sink whose front side is bonded to the second electrode through the intermediary of an insulating material;
• and
• a transfer resin in which the semiconductor device, the first electrode, the second electrode, and the insulating material are embedded,
• wherein the heat sink has a protruding portion that is exposed from and protrudes from part of a rear side of the transfer resin and a cooling fin fixed to an endface portion of the protruding portion,
• wherein the case of the jacket has a penetration hole that penetrates a portion thereof between the flow path and the front side of said case,
• wherein when the semiconductor power module is mounted on the case of the jacket, the protruding portion of the heat sink is inserted into the penetration hole in the case, and the endface portion of the protruding portion and the cooling fin are exposed in the flow path,
• wherein the front-end portion of the cooling fin abuts on the inner wall surface of the flow path,
• wherein a ring-shaped packing is inserted into a groove portion formed between a side wall portion of the protruding portion of the heat sink and an inner wall portion of the penetration hole of the jacket or a side wall portion of the case,
• wherein the inner wall portion of the penetration hole or the side wall portion of the case and the side wall portion of the protruding portion compress the ring-shaped packing in a radial direction of the ring-shaped packing, and
• wherein elastic force of a spring member presses the front-end portion of the cooling fin to the inner wall surface of the flow path.