A Fast-Recovery Split Gate Trench MOSFET Integrated with Area-Efficient Schottky Contacts

A Fast-Recovery (FR) Split Gate Trench (SGT) MOSFET integrated with area-efficient Schottky contacts is proposed and investigated in this paper. The proposed FR SGT MOSFET features integrated Schottky diode at the source-side to improve the reverse recovery characteristics. The vertical drift region uses a multi-step epitaxial growth to realize a non-uniform doping profile, allowing the FR SGT MOSFET a more uniformly electric field distribution in the blocking state. Both technology computer-aided design (TCAD) simulations and experiments were performed to evaluate the proposed device. The proposed device exhibits an improved body diode reverse recovery characteristic. The reverse recovery charge $(\boldsymbol{Q}_{\mathbf{rr}})$ and the softness factor $(\boldsymbol{S})$ shows an improvement of 41% and 15%, respectively, when compared to its state-of-the-art counterparts. The integrated Schottky diode improves the dynamic performance without compromise on the third quadrant performance and the specific on-resistance.