Waveform characterization and modeling of dynamic charge behavior of InGaP-GaAs HBTs

This study presents a novel time-domain characterization method for the first time, to reveal dynamic charge behavior of HBTs. The charge model plays an important role in power InGaP-GaAs HBT amplifiers designed with self-biasing. It is shown that charge-storage and extraction from the base of the HBT at a high-power drive cannot be described by the conventional quasi-static model. A new collector-base charge model is proposed to account for the time-response of the devices.