A 4H-SiC super-junction trench MOS barrier Schottky structure with an enhanced figure of merit

Abstract This paper investigates an improved trench MOS barrier Schottky (TMBS) structure, designated as a super-junction-TMBS (SJ-TMBS), which incorporates an SJ structure beneath the deep trench sidewall by ion implantation doping, based on the conventional TMBS (C-TMBS). Compared with C-TMBS, the proposed SJ-TMBS synergistically combines the advantages of both TMBS and SJ configurations. Via numerical simulations and analytical models, the SJ-TMBS demonstrates significant reduction in specific on-resistance ( R on,sp ) while maintaining the same breakdown voltage (BV) compared to its conventional counterpart. This improvement primarily originates from the electric field modulation induced by the SJ structure, which enables uniform electric field distribution and permits higher doping concentration in the drift region. Furthermore, the figure of merit (FOM, BV 2 / R on,sp ) is maximized via optimization of P-pillar parameters. The results indicate that the SJ-TMBS achieves 77.3% reduction in R on,sp and 377.9% enhancement in FOM compared with C-TMBS, while maintaining low electric field intensity at the Schottky interface.