COMPARATIVE INVESTIGATION OF INGAP/GAAS/GAASBI AND INGAP/GAAS HETEROJUNCTION BIPOLAR TRANSISTORS

摘要

In this article the characteristics of In_(0.49)Ga_(0.51)P/GaAs/GaAs_(0.975)Bi_(0.025) and In_(0.49)Ga_(0.51)P/GaAs heterojunction bipolar transistor (HBTs) are demonstrated and compared by two-dimensional simulated analysis. As compared to the traditional InGaP/GaAs HBT, the studied InGaP/GaAs/GaAsBi HBT exhibits a higher collector current, a lower base-emitter (B-E) turn-on voltage, and a relatively lower collector-emitter offset voltage of only 7 mV. Because the more electrons stored in the base is further increased in the InGaP/GaAs/GaAsBi HBT, it introduces the collector current to increase and the B-E turn-on voltage to decrease for low input power applications. However, the current gain is slightly smaller than the traditional InGaP/GaAs HBT attributed to the increase of base current for the minority carriers stored in the GaAsBi base.