3-D Segmented Gate Concept: A New IGBT Solution for Reduced Loss and Improved Safe-Operating Area

In this article, the “segmented gate (SG)” concept is proposed and implemented in trench gate to realize both low loss and wide safe-operating area (SOA) for insulated-gate bipolar transistors (IGBTs). The poly gate of the proposed IGBT is split into segments along the trench and each segmented poly gate is surrounded by the poly emitter. This unique 3-D trench architecture is demonstrated under numerical studies to be highly effective in enhancing the short-circuit ruggedness, the turn-off capability, and the latch-up immunity. It enables a 37% reduction in saturation current and a 90% reduction in Miller capacitance. The proposed design also shows an improved trade-off relationship between ON-state voltage and turn-off loss. For the same turn-off loss, the ON-state voltage of the proposed IGBT is reduced by 0.25 V when compared with the conventional carrier-stored trench IGBT.