A Comparative Study on the DC, RF Characteristics of InGaAs /InP Single Heterojunction Bipolar Transistors with Different Collector Layer Thickness

摘要

In this paper, a reliable method was applied to make devices with a simple InP-based heterojunction bipolar transistors(HBT) construction process. Satisfactory maximum oscillation frequency (f_(max) and cut-off frequency (f_T) were obtained in a simple layer structure. The thickness of HBT collector layer was 3500 (sample A) and 5000 (sample B). The emitter size of HBT was measured to be 1.2x6μm~2. In sample A, f_T and f_(max) were obtained to be 143 GHz and 176 GHz, respectively. In case of sample B, f_T and f_(max) were to be 126 GHz and 127 GHz, respectively. HBT with the thinner collector layer thickness shows better frequency characteristics. The collector current density in sample A is acquired to be 200kA/cm~2 at the peak frequency.