A High Voltage Superjunction MOSFET with Enhanced Reverse Recovery Performance

A high voltage superjunction MOSFET (SJ-MOSFET) for enhanced reverse recovery performance is proposed and demonstrated. By introducing an oxide-pillar to separate the N-pillar and P-pillar, and forming a Schottky diode between the Source contact and the P-base on the top of P-pillar, the hole carriers injecting into the P-pillar is significantly reduced during the reverse conduction state, hence hole density in the drift region reduced dramatically, which results in an enhanced reverse recovery performance. The simulation results show that, compared with the conventional SJ-MOSFET, the proposed device achieves 42.3% lower reverse recovery charge. Besides, the proposed SJ-MOSFET achieves a lower specific-ON resistance and a higher static breakdown voltage than the conventional SJ-MOSFET.