Etched field limiting rings termination based on N-P-N sandwich epitaxial wafer for high reliability 4H-SiC devices

In this paper, an etched field limiting ring termination based on N-P-N sandwich epitaxial wafer (E-FLRs termination) is designed and fabricated. The proposed E-FLRs termination realizes a blocking voltage (BV) of 1550 V. In addition, the E-FLRs provide a P-buried layer in the epitaxial layer. The PN junction composed of the P buried layer and the drift region can block the potential between the surface of the scribe line and the drain, restrain the current flowing between the scribe line and the drain, and prevent the scribe line from being broken down. The simulation results show that when the scribe line and the source metal are short-circuited, the SiC device with E-FLRs termination only generates a 15 ns capacitive displacement current, and the lattice temperature of the SiC device hardly changes.