On the breakdown behaviors of InP/InGaAs based heterojunction bipolar transistors (HBTs)

The breakdown behaviors of InP/InGaAs single heterojunction bipolar transistor (SHBT) and double heterojunction bipolar transistor (DHBT) are studied and demonstrated. By using a composite collector structure at the base–collector heterojunction, the undesired current-blocking effect, switching, hysteresis phenomenon usually found in an InP/InGaAs conventional DHBT are not observed in our DHBT device. Experimentally, as compared with the studied SHBT, the studied DHBT reveals the enhanced breakdown voltages, lower collector leakage current ICO, and smaller electron impact ionization α. Moreover, the temperature-dependent electron impact ionization characteristics and electrical reliability for both devices are also studied. Therefore, the studied DHBT device provides the promise for millimeter-wave and power circuit applications.