Emitter size effects on DC current gain and RF performance in InP/InGaAs HBT's

Abstract

We have presented a comprehensive investigation of the emitter size effects on DC current gain, cut-off frequency (f(T)), and maximum oscillation frequency (f(MAX)) in InP/InGaAs HBT's. The surface recombination current ( J(SR)) was observed to be 3.88 mu A/mu m which was slightly worse than the conventional GaAs/AlGaAs HBT's with AlGaAs ledge. We also presented a simple formula for f(T) and emitter area. Moreover, a guide-map which gives insight into the relation between the emitter area and high frequency performance was presented based on the investigation of the extracted parameters determining the RF performance.