Numerical Simulation Of InP-based HBT

The heterojunction bipolar transistor (HBT) has been used in the applications of low phase oscillator, high efficiency amplifier, and broadband amplifier, because of its advantages in the field of high-frequency, high-speed, high-power-density, low-phase-noise, and good-linearity. With continuous development of HBT applications, establishing the precise device model plays an important role in design and fabrication of integrated circuit. Device simulation can not only reduce the production period, but also greatly cut down the cost, and good prediction for the future developing direction. Owing to very high electron-mobility, InP/InGaAs material applies better to HBT devices and gets high current gain and high-frequency performance.In order to investigate InP/InGaAs HBT, hydrodynamics model can be adopted. In hydrodynamics model, the average energy of carriers includes kinetic energy. Because of very high average velocity of carriers in small size semiconductor devices, kinetic energy can not be neglected.Considering basic properties of InP/InGaAs material, the low-field-mobility model, the high-field-mobility model has firstly established in this paper. These models can reflect better the transport process and the actual relationship between velocity of the carriers and electric field in the material. For the fundamental physical process of HBT devices, SRH, Radiative, Auger recombination and thermionic emission models have already established in the paper. We can get comparatively accurate DC characteristic after simulation. Based on the result of simulation, we have discussed basic influence factors on device performance. Finally we probe some important fabrications of HBT devices, in order to start experiment.