Anomalous current injection phenomena at the emitter-base junction of InP/InGaAs HBTs

Abstract

An analysis of the injection phenomena in the InP/InGaAs heterojunction bipolar transistors passivated with Si/sub 3/N/sub 4/ has been made. Two different mechanisms are shown to be responsible for the anomalous carrier injection at the emitter-base heterojunction in the low voltage range. One is based on the thermionic emission in an accumulation region along the emitter edges and the other based on the preferential electron tunnelling, also in a thin region along the emitter edges.