Semiconductor Device

A semiconductor device has a power transistor N of vertical structure and a temperature detection element configured to detect abnormal heat generation by the power transistor N. The power transistor N includes a first electrode formed on a first main surface side (front surface side) of a semiconductor substrate , a second electrode formed on a second main surface side (rear surface side) of the semiconductor substrate , and pads - positioned unevenly on the first electrode . The temperature detection element is formed at a location of the highest heat generation by the power transistor N, the location (near the pad where it is easiest for current to be concentrated) being specified using the uneven positioning of the pads -.