An Ultra-Low Qrr Cell-Distributed Schottky Contacts Sj-Mosfet With Integrated Isolated Nmos

An ultra-low reverse recovery charge (Q(rr)) Cell-Distributed Schottky Contacts (CDSC) Superjunction MOSFET (SJ-MOSFET) is proposed in this paper. The proposed structure features that an isolated lateral NMOS is integrated in p-body region of SJ device. The conduction of the SJ-VDMOS intrinsic diode can be effectively suppressed by the reversed body diode of the integrated NMOS, which almost eliminates hole current in the voltage-sustaining layer during freewheeling period. Combining the CDSC with the integrated NMOS, an excellent reverse recovery characteristic of body diode in SJ-MOSFET is realized. The simulated results show that the proposed SJ-MOSFET can achieve a 97% and 91.8% lower Q(rr) compared with the conventional and the CDSC SJ-MOSFETs at the same I-F of 3.2A. Moreover, the Figure-of-Merit (FOM = R-on,R-sp. Q(rr)) of the proposed structure is only 29.3m Omega.nC, which is much superior to that of the conventional and the CDSC SJ-MOSFETs.