200 V Superjunction N-Type Lateral Insulated-Gate Bipolar Transistor With Improved Latch-Up Characteristics

This paper evaluates the technique used to improve the latching characteristics of the 200 V n-type superjunction (SJ) lateral insulated-gate bipolar transistor (LIGBT) on a partial silicon-on-insulator. SJ IGBT devices are more prone to latch-up than standard IGBTs due to the presence of a strong pnp transistor with the p layer serving as an effective collector of holes. The initial SJ LIGBT design latches at about 23 V with a gate voltage of 5 V with a forward voltage drop (V_ON) of 2 V at 300 A/cm². The latch-up current density is 1100 A/cm². The latest SJ LIGBT design shows an increase in latch-up voltage close to 100 V without a significant penalty in V_ON. The latest design shows a latch-up current density of 1195 A/cm². The enhanced robustness against static latch-up leads to a better forward bias safe operating area.