A U-Shaped Channel SOI-LIGBT With Dual Trenches

Abstract

This paper proposes a U-shaped channel silicon-on-insulator lateral insulated gate bipolar transistor (SOI-LIGBT) with dual trenches to reduce the turn-off loss while keep the low ON-state voltage drop. The device features a U-shaped gate trench (G1) and a U-shaped hole-barrier trench (G2). By introducing the dual trenches, enhanced carrier stored effect at the emitter side, more uniform carrier distribution in the drift region, and low carrier density at the collector are realized, resulting in decreases of ON-state voltage drop ( ${V}_{\mathrm{\scriptscriptstyle ON}}$ ) and turn-OFF loss ( ${E}_{\mathrm{\scriptscriptstyle OFF}})$ . The proposed SOI-LIGBT offers an ${E}_{\mathrm{\scriptscriptstyle OFF}}~52.3$ % lower than the conventional planar-gate U-shaped channel SOI-LIGBT at the same ${V}_{\mathrm{\scriptscriptstyle ON}}$ of 1.22 V. Moreover, the proposed SOI-LIGBT exhibits a latch-up free characteristic at the current density larger than 1200 A/cm2.