PURPOSE: To dispense with maintenance time required by the friction of a junction surface, and reduce working time, by installing a pressing jig which retains the rear side of a semiconductor pellet and can move freely upward and downward, and a retaining stand which retains a table for a TAB use on which a corrosion resistant protecting member is laminated and contains a heater.

CONSTITUTION: A heater 22 is so operated on a heater-built in retaining stand 20 side that the surface temperature of an upper surface protecting member 21 is kept always at a junction temperature of about 550°C. A vacuum pump is so driven on a pressing jig 10 side that the rear side of a semiconductor pellet 5 is vacuum-sucked on the lower end surface of a punch part 11, and a bump electrode 5a on the surface side is positioned on a corresponding inner lead 4. A through hole 2a into which an inner lead 4 of a table for a TAB use stretches is retained on a heater 22 of the heater-built-in retaining stand 20, and the temperature of each inner lead 4 is raised. A pressing jig 10 is made to descend, and the bump electrode 5a is superposed on the corresponding inner lead 4, which are pressed with pressure. At this time, heat is hard to travel upward, because a rubber member 12 of the pressing jig 10 has thermal insulation properties.