A new dual-bandgap SiC-on-Si p-emitter, SiGe n-base, lateral Schottky metal-collector (PNM) HBT on SOI with reduced collector-emitter offset voltage

We introduce a novel approach, called dual bandgap SiC-on-Si emitter, to reduce the collector emitter offset voltage in the case of wide bandgap SiC-emitter PNP HBTs. In our approach, the collector-emitter offset-voltage is reduced significantly by partially eliminating the built-in potential difference between the emitter-base junction and collector-base junction. We have evaluated the performance of the proposed device in detail using 2D device simulation. The proposed dual bandgap SiC-on-Si P-emitter SiGe N-base lateral Schottky metal-collector (PNM) HBT is shown to exhibit a current gain close to that of the wide bandgap emitter (SiC) PNP HBT while its collector-emitter offset-voltage is significantly lower than that of the SiC PNP HBT. The transient response of the proposed structure is also much superior due to its Schottky collector.