PURPOSE: To prevent the occurrence of wire sweep of bonding wires by reinforcing the bonding wires by connecting the bonding wires transversely to each other with electric insulating reinforcing material.

CONSTITUTION: After a wire-bonding process, while the temperature of a bonding wire 24 is still high, a reinforcing tape 32 is put on the bonding wire 24 with an adhesive layer 34 faced downwards. After attaching the reinforcing tape 32 to the bonding wire 24, a semiconductor chip 10 and a lead frame 12, which are connected to each other with bonding wires 24, are so sealed into one body with sealing resin that outer leads 18 may be exposed. Due to this structure, the bonding wires 24 are linked to each other with the reinforcing tape 32 and thereby are made into one strong-structured body and furthermore, the length of one bonding wire 24 which needs to be supported is made shorter by the reinforcing tape 32. By this method, wire sweep to be caused by injection pressure of sealing resin 26 is avoided.