InP-based HBTs and their perspective for microwave applications

Significant progress has been made over the past few years in both the technology and microwave performance of InP-based heterojunction bipolar transistors (HBTs). Emphasis has, however, been placed mainly on transistor performance. Other critical issues have largely been ignored, including the influence of InGaAs on device thermal resistance, the role of base-collector leakage current, and the phenomenon of thermal instability. This paper first briefly reviews recent microwave results achieved to date and then investigates the aforementioned critical issues that affect their use in microwave applications.