Optimized design for 4H-SiC power DMOSFETs

An optimized tradeoff between blocking voltage and specific ON-resistance for 4H-silicon carbide power vertical double-implanted metal-oxide-semiconductor field-effect transistor (DMOSFET) is exclusively obtained as a function of doping concentration in the drift region. Based on a novel analytical model of the electric field in the gate oxide of 4H-SiC DMOSFETs, we propose a closed-form equation of the Junction FET (JFET) region width and the drift thickness as function of doping concentration without using fitting and empirical parameters to obtain the maximum figure of merit. Model results are successfully verified with TCAD numerical simulations, covering a wide range of device performances, and experimental results.