Semiconductor device

A semiconductor device comprising:

• an insulation circuit substrate;
• a semiconductor element mounted on the insulation circuit substrate;
• and a cooler which cools the semiconductor element connected to the insulation circuit substrate, wherein
• the cooler comprises:
• a heat dissipation substrate joined to the insulation circuit substrate;
• a fin provided on a surface opposite to the joining surface with the insulation circuit substrate on the heat dissipation substrate;
• a case which houses the fin and is connected to the heat dissipation substrate;
• an inlet and an outlet for a coolant which are provided on side walls of the case, the side walls being opposed to each other, and are provided at diagonal positions of the case;
• an introduction path which is connected to the inlet and is formed along the inner surface of a first side wall on which the inlet of the case is provided;
• a discharge path which is connected to the outlet and is formed along the inner surface of a second side wall on which the outlet of the case is provided;
• and a cooling flow channel which is formed at a position where the fin is housed between the introduction path and the discharge path, and
• the height of the opening of the inlet is larger than the height of the introduction path, and, at a connecting portion between the inlet and the introduction path, an inclined surface which is inclined in the longitudinal direction of the introduction path from the bottom surface of the connecting portion is provided.