A Design Parametric Effect Study on Floating Guard Ring for 1200V SiC Power MOSFET Application

A study on the simulation and fabrication of 1200 V floating guard rings with different design parameters, aimed at protecting 4H-SiC VDMOSFETs for high power ratings, is presented. The comprehensive parametric effects of the guard ring on the breakdown characteristics have been thoroughly investigated. The breakdown characteristics of various guard ring structures were simulated using TCAD (Technology Computer Aided Design) simulation and measured on the fabricated devices. A concise guideline for designing floating guard rings with high breakdown voltage capability is provided. Finally, it is demonstrated that the breakdown voltage of the fabricated guard ring can reach up to 1560 V for 1200 V applications.