OPTIMIZATION OF ALGAAS/GAAS HETEROJUNCTION BIPOLAR-TRANSISTORS FOR CURRENT GAIN, CUTOFF FREQUENCY AND MAXIMUM FREQUENCY

The intrinsic HBT configurations (e.g. doping concentrations and layer thicknesses) are optimized for the current gain, cutoff frequency, and maximum oscillation frequency. The optimization is carried out based on an analytical HBT model which includes the high-current and thermal effects. The effects of the emitter, base and collector doping concentrations and layer thicknesses on the HBT performance are calculated and discussed. Optimal HBT intrinsic configurations, together with the corresponding HBT performance, are also suggested for both high-current and low-current regions.