An Investigation of Electric Field and Breakdown Voltage Models for a Deep Trench Superjunction SiC VDMOS

The theoretical analysis of breakdown model for a deep trench superjunction (DT-SJ) SiC VDMOS is presented in this paper. The vertical electric field distribution is derived by the electric field decomposition. Then, a fitting dependence of the critical electric field on the doping concentration for the device is obtained, based on which, the model of breakdown voltage is given for the DT-SJ SiC VDMOS. Analytical results are compared with simulative results with the same thicknesses of drift region from $8~\mu \text{m}$ to $16~\mu \text{m}$ and the doping concentrations from $4\times 10^{16}$ cm $^{-3}$ to $8\times 10^{16}$ cm $^{-3}$ . It is numerically demonstrated that the errors between model and simulation are less than 3% when N pillar and P pillar have the same width of $1\mu \text{m}$ .