Performance of 200 V CMOS compatible auxiliary cathode lateral insulated gate transistors

The authors report the performance of various anode-shorted auxiliary cathode lateral insulated gate transistor (ACLIGT) structures fabricated using a 2.5 μm digital CMOS compatible HVIC process. The reverse breakdown voltage of the ACLIGT is comparable to that of an equivalent anode shorted lateral insulated gate transistor (LIGT). The results indicate that, by placing an auxiliary cathode and an extended p-buried layer of an anode-shorted LIGT, the holes flowing into the p-well can be diverted to overcome the latch-up problems of the LIGT in an ACLIGT. The LIGT shows latch-up at 140 mA, which corresponds to a current density of 340 A/cm² while the ACLIGT structures do not show latch-up. The measured turn-off characteristics of the ACLIGT reveal a turn-off time of less than 250 ns while an equivalent LIGT shows a turn-off time of 350 ns