A semiconductor device has a plurality of electronic components mounted on an insulating substrate formed with a metal layer, and electrically connected to each other or to the metal layer; a positioning wire member having a predetermined diameter and a predetermined length, and bonded to each of the plurality of electronic components or to the metal layer; a lead frame disposed to bridge and electrically connect the plurality of electronic components to each other or between the metal layer and the electronic components; and an opening having a size capable of inserting the wire member therethrough formed to penetrate through the lead frame, to join the lead frame to each of the electronic components or the metal layer at a predetermined position therein. The lead frame is positioned on the insulating substrate by inserting the wire member into the opening.