Prospects of InP/InGaAs HBTs for low power and high speed analogue applications

In this paper, we investigate the inherent advantages of the InP/InGaAs system for low power and high speed analogue applications. Heterojunction Bipolar Transistors (HBTs) based on various III-V compound semiconductors including AlGaAs/GaAs, InGaP/GaAs and InP/InGaAs, have been fabricated and transistor characteristics were measured accordingly. To demonstrate the suitability of using InP-based HBTs for low power analogue applications, we compared the turn-on voltages of the InP/InGaAs HBTs with typical GaAs-based HBTs as well as with the commercial Si bipolar transistors. The results obtained showed clearly that, among all the material systems studied, the InP/In_0.53Ga_0.47As HBTs have the lowest turn-on voltage (0.2 V). This is in good agreement with the theoretical prediction