Semiconductor device

A semiconductor device comprising:

• an insulating substrate including a circuit pattern;
• a semiconductor chip mounted on the insulating substrate and connected to the circuit pattern;
• an overcurrent interruption mechanism constituted with a same material as a material of the circuit pattern, connected to the circuit pattern in series;
• a base plate;
• and
• a case joined on the base plate,
• wherein when an overcurrent flows, the overcurrent interruption mechanism melts and is cut,
• the insulating substrate is provided on the base plate inside the case,
• the case includes an electrode,
• the circuit pattern includes a first circuit pattern connected to the semiconductor chip and a second circuit pattern connected to the electrode,
• one end of the overcurrent interruption mechanism is directly connected to the first circuit pattern with solder,
• the other end of the overcurrent interruption mechanism is connected to the second circuit pattern with solder,
• the overcurrent interruption mechanism includes a first conductor portion, a second conductor portion, and a constricted portion connected between the first conductor portion and the second conductor portion,
• the first conductor portion is directly connected to the first circuit pattern with solder,
• the second conductor portion is connected to the second circuit pattern with solder, and
• the overcurrent interruption mechanism is a single integral piece of the same material as the material of the circuit pattern.