Turn-off failure of IGBTs under clamped inductive load

This paper reports the mechanism of failure of IGBTs during clamped inductive switching stress. With the help of measurements and two-dimensional (2-D) numerical simulations, the turn-off failure of IGBTs under clamped inductive load is shown to occur due to thermally assisted carrier multiplication at the reverse biased planar p-base n-drift junction. The failure mechanism is unchanged even if the IGBT is susceptible to latch-up in static conditions.