A semiconductor device includes a semiconductor substrate having a first side and a second side opposite the first side, an active area and a through contact area, the active area including a transistor structure having a control electrode, the through contact area including a semiconductor mesa having insulated sidewalls. The semiconductor device further includes a first metallization on the first side in the active area and a recess extending from the first side into the semiconductor substrate and between the active area and the through contact area and including in the through contact area a horizontally widening portion, the recess being at least partly filled with a conductive material forming a first conductive region in ohmic contact with the semiconductor mesa and the transistor structure. The semiconductor device also includes a control metallization on the second side and in ohmic contact with the semiconductor mesa.