Semiconductor device

The semiconductor device includes: a semiconductor chip (12) which is an SiC substrate with an element formed thereon and which has main electrodes formed respectively on one surface and a rear surface thereof; a first heat sink (16) that is disposed on the one surface; a second heat sink (24) that is disposed on the rear surface; a wiring unit (20) that is interposed between the second heat sink and the semiconductor chip and electrically relays the main electrode on the rear surface and the second heat sink; and connection members (18, 22, 26) that are disposed, respectively, between the main electrode on the one surface and the first heat sink, between the main electrode on the rear surface and the wiring unit, and between the wiring unit and the second heat sink. The wiring unit has a plurality of types of metal layers (20a, 20b, 20c, 20d) stacked in the thickness direction, a coefficient of linear expansion in at least a direction orthogonal to the thickness direction is in a range greater than that of t