The fabrication and characterization of 4H SiC power UMOSFETs

The fabrication of 4H-SiC vertical trench-gate metal-oxide-semiconductor field-effect transistors (UMOSFETs) is reported in this paper. The device has a 15-μm thick drift layer with 3×10¹⁵ cm^-3 N-type doping concentration and a 3.1-μm channel length. The measured on-state source-drain current density is 65.4 A/cm² at V_g=40 V and V_DS=15 V. The measured threshold voltage (V_th) is 5.5 V by linear extrapolation from the transfer characteristics. A specific on-resistance (R_sp-on) is 181 mΩ·cm² at V_g=40 V and a blocking voltage (BV) is 880 V (I_DS=100 μA@880V) at V_g=0 V.