A semiconductor chip including a main electrode and a control electrode is bonded to a substrate. A wiring chip including a first electrode, a second electrode and a wiring is bonded to the substrate. A main electrode member is bonded to the main electrode. A control electrode member is bonded to the second electrode. The control electrode is bonded to the first electrode with a connection member. The semiconductor chip, the substrate, the wiring chip, the main electrode member, the control electrode member and the connection member are putted into a mold and are sealed with sealing material by injecting the sealing material into the mold in a state that distal end surfaces of the main electrode member and the control electrode member are pressed against a buffer material provided between the main electrode member/the control electrode member and the mold. The sealing material is not ground.