Insulated gate semiconductor device having a clamping element to clamp gate-emitter voltage and method of manufacturing thereof

摘要

The gate of an IGBT is connected to a gate terminal. One end of a clamping element is connected to an anode terminal. A voltage higher than a clamping voltage is applied between the gate and the emitter, to thereby test the dielectric breakdown voltage of a gate insulating film of the IGBT. The IGBT is eliminated which has a gate insulating film at a dielectric breakdown voltage failing to fall within its proper distribution range. Thereafter, a gate terminal and an anode terminal are wire bonded in the normal IGBT.