Analytical modelling of base transit time and gain of InP/InGaAs HBTs including effect of temperature

An analytical model of InP-InGaAs Heterojunction Bipolar Transistors is presented in this paper. Two important factors for determining the performance of a transistor are base transit time (τ_b) and current gain (β). Variations of base transit time and gain with temperature and other device parameters for both uniform and nonuniform base doping profile are studied here. Dependance of band gap on composition and dependence of mobility on temperature are also taken into account in the model.