Simulation study of a novel current limiting device: a vertical 6H-SiC etched AccuJFET

Considering fault current limiters for serial protection, a lot of structures exist, from regulation to other complex systems. Up to now, only a few semiconductor current limiter structures have been described. Although Current Regulative Diode components exist, the voltage and current capabilities (V_BR=100 V, I_max=10 mA), do not allow to use them in power systems. A study of a silicon CRD demonstrates the thermal and electrical limitations of silicon. This paper presents a new bi-directional current limiter structure based on a vertical 6H-SiC etched AccuJFET, with both buried gate and source. This device was designed for applications like motor starting phase, short circuit protection, circuit breaker with higher ratings. Simulations were performed with ISE TCAD tools to evaluate static and transient electrical characteristics of the AccuJFET, according to several specifications: voltage capability, current rating, time during which the device can sustain a short circuit. Simulations allow one to estimate geometrical and doping characteristics as well as the technological steps to realize such a component