Optimization of specific on-resistance of a two-zone variational vertical doping superjunction with insulating layers

Abstract A novel two-zone variational vertical doping superjunction structure with insulating layers (I-VVDSJ) is proposed. The path length of the impact ionization integral can be shortened by the insertion of a lateral insulator layer. This allows for a higher average doping concentration and a superior specific ON-resistance ( R on,sp ). Two-dimensional electric field ( E -field) distributions are unified for the entire structure by utilizing the sign function for optimization of R on,sp with MATLAB and MEDICI. Compared with a conventional superjunction structure for breakdown voltage (BV) larger than 700 V, the optimized R on,sp ( R on,sp(opt) ) can be reduced by over 27%. Formulae for the design parameters are proposed as a function of BV and aspect ratio (AR). Furthermore, R on , sp ( opt ) = δ ( 2.278 × 10 − 5 ) AR − 1.295 BV 2.33 mΩ cm 2 is proposed to guide the design for the I-VVDSJ structure with the factor δ representing the junction field effect transistor effect.