集成高K栅介质与分裂栅的4H-SiC超级结MOSFET

A 4H-SiC superjunction(SJ)MOSFET(SJMOS)with integrated high-K gate dielectric and split gate(HKSG-SJMOS)is pro-posed in this paper.The key features of HKSG-SJMOS involve the utilization of high-K(HK)dielectric as the gate dielectric,which surrounds the source-connected split gate(SG)and metal gate.The high-K gate dielectric optimizes the electric field distri-bution within the drift region,creating a low-resistance conductive channel.This enhancement leads to an increase in the break-down voltage(BV)and a reduction in the specific on resistance(Ron,sp).The introduction of split gate surrounded by high-K dielectric reduces the gate-drain capacitance(Cgd)and gate-drain charge(Qgd),which improves the switching characteristics.The simulation results indicate that compared to conventional 4H-SiC SJMOS,the HKSG-SJMOS exhibits a 110.5%enhance-ment in figure of merit(FOM,FOM=BV2/Ron,sp),a 93.6%reduction in the high frequency figure of merit(HFFOM)of Ron,sp·Cgd,and reductions in turn-on loss(Eon)and turn-off loss(Eoff)by 38.3%and 31.6%,respectively.Furthermore,the reverse recovery characteristics of HKSG-SJMOS has also discussed,revealing superior performance compared to conventional 4H-SiC SJMOS.