In a semiconductor chip having electrodes formed on the top surface, and electrodes or an insulation layer formed on the back surface, the top-surface electrodes are loop-connected with the back-surface electrodes by wire bonding, or, the top-surface electrodes are connected with the back-surface electrodes or an insulation layer by conductive clip, or by deposited conductive materials. The semiconductor chips thus produced are stacked, and wires, conductive clips, or conductive materials are connected and fixed to each other to produce a stacked semiconductor device in which semiconductor chips of the same size are densely packaged. Thus, a semiconductor device is provided which enables high-density packaging of semiconductor chips even of the same size.