High-speed InGaAs/InP composite collector bipolar transistors

Summary form only given. The authors describe a composite collector bipolar transistor structure capable of high-speed and high breakdown voltage (BV_CEO). The structure uses a composite collector of InGaAs and InP. f_T=120 GHz at V_CE=1.5 V at a current density of 77 kA/cm² were obtained. The breakdown voltage BV_CEO is greater than 5 V, and the output conductance is essentially independent of the collector voltage. Microwave transistors with an emitter size of 3×10 μm² were fabricated by a self-aligned process. Microwave measurements were made from 100 MHz to 40 GHz as a function of the collector current and V_CE. The authors have also fabricated and tested transimpedance amplifiers based on the composite collector transistors