Investigation of InP/InGaAs/InP double heterojunction bipolar transistor

The epitaxy growth, the design of device structure, the fabricating process and performance of InP/InGaAs/InP double heterojunction bipolar transistor (DHBT) are presented as well as the application in the low phase noise oscillator. InP/InGaAs/InP DHBT DHBTs are realized using self-aligned-emitter process. For a device with a emitter contact of 1.5 μm × 10 μm, the DC gain at small current is about 25, the collector-emitter break-down voltage BV CEO > 10 V, the current gain cutoff frequency f t and the a maximum frequency of oscillation f max is 50 and 55 GHz, respectively.