Diffusive base transport in narrow base InP/Ga0.47In0.53As heterojunction bipolar transistors

Abstract
The common emitter current gain of InP/Ga0.47In0.53As heterojunction bipolar transitors having a base doping level of 7×1019 cm−3 is found to increase monotonically with decreasing base thickness in the range of 200–1000 Å. The variation of the gain with base thickness WB is proportional to 1×W2B, as expected for diffusive base transport, and a high injection efficiency.