The back surface of a semiconductor chip (16) is exposed from the back surface of an insulating resin (13), and a metal plate (23) is affixed to this semiconductor chip (16). The back surface of this metal plate (23) and the back surface of a first supporting member (11) are substantially within a same plane, so that it is readily affixed to a second supporting member (24). Accordingly, the heat generated by the semiconductor chip can be efficiently dissipated via the metal plate (23) and the second supporting member (24).