Novel anode Schottky trench contact controlled SOI LIGBT with low loss and snapback-free

Abstract

The novel shorted-anode silicon-on-insulator lateral insulated gate bipolar transistor (SOI LIGBT) with low loss and snapback-free is proposed and studied by numerical simulation, named the anode Schottky trench contact (ASTC) LIGBT in this paper. Due to the fixed anode resistance, the conventional shorted-anode LIGBT structure has the contradiction between the snapback-free and high forward voltage drop (V_F). The novelty of proposed device is that, it makes full use of the lateral space charge region formed by the Schottky trench contact, so as to introduce the changed anode resistance by varying the anode voltage bias (V_AC). The low V_AC in the on-state achieves completely snapback-free with fully occupied channel by depletion region. The high V_AC value in case of the turn-off process achieves fully opening of electron flowing channel with the disappearance of depletion region, which is conducive to the realization of barrier-free process for the electron extraction. Under the same V_F of 1.42V at the anode current density J_AC=100A/cm², the turn-off time and turn-off loss (E_off) of proposed ASTC LIGBT is reduced by 41.5% and 37.9%, respectively, compared with the conventional LIGBT. Therefore, it can be concluded that the proposed ASTC LIGBT achieves the best trade-off performance between V_F and E_off.