A Comprehensive Analytical Study of Dielectric Modulated Drift Regions—Part I: Static Characteristics

A comprehensive study of dielectric modulated (DM) drift regions for power devices is presented in this paper. The performance of this structure is theoretically analyzed and compared with both conventional and superjunction (SJ) structures. In this paper, an analytical model for DM drift regions with cylindrical cells is proposed and compared with linear cells. An optimal tradeoff between breakdown voltage (BV) and specific ON-resistance (R
_ON,sp
) is obtained by a methodology developed in this paper. 3-D simulations of DM structures with hexagonal cells approximated by cylindrical cells are conducted to verify the analytical model. Optimal BV-R
_ON,sp
tradeoffs for devices with conventional and SJ drift regions are also obtained through the same methodology and verified by 3-D simulations. Static characteristics of these three different drift region structures in both Si and SiC power devices are compared.