Temperature-dependent characteristics of InP/In/sub 0.53/Ga/sub 0.34/Al/sub 0.13/As heterojunction bipolar transistor

Temperature-dependent DC performances of InP/InGaAlAs heterojunction bipolar transistors (HBTs) using the InGaAlAs quaternary alloy as the base and collector layers are studied and reported. When compared with conventional InP/InGaAs HBTs, the device studied exhibits a higher common-emitter breakdown voltage and a lower output conductance even at high temperature. In addition, with decreasing temperature from 25 toward -196/spl deg/C, an irregular temperature behavior of current gain has been investigated.