OBSERVATION OF CURRENT GAIN COLLAPSE IN LARGE-AREA HBT WITH RECTANGULAR EMITTER AND ETCHED BASE

摘要

We observe for the first time the current gain collapse in a large-area heterojunction bipolar transistor (HBT) with a rectangular emitter and an etched base when the HBT is operated under high power density. The collapse manifests itself by a distinct abrupt decrease of collector current in the common-emitter current-voltage characteristics. In this study, we demonstrated this unwanted phenomenon by comparing the common-emitter characteristics of the same device measured by Tektronics-577 curve tracer and HP-4145B semiconductor analyzer, respectively.