A Fast and Effective Design Method for Multi-Layer Floating Field Ring Optimization in SiC Floating Island Devices

Silicon carbide floating island devices have been widely studied because of their ability to improve the trade-off between on-specific resistance and breakdown voltage. The traditional multi-layer floating field ring (MFFR) termination design method needs a lot of simulation, trail and error to find the optimal parameters. This paper proposes a novel structural parameter design method to complete the efficient optimization of the floating island device termination region. Based on the structural characteristics and constraint conditions of the field limiting ring unit, the optimal field limiting ring parameters are designed by the algorithm and verified by Technology Computer Aided Design (TCAD) platform. Compared with the traditional linear field ring spacing design method, the breakdown voltage and the termination length efficiency are improved to 4700V and 44 V/µm, respectively. This method reduces the difficulty of multi-layer termination design and improves the design efficiency. In addition, this method has a relatively large process window in terms of the ring spacing offset.