High frequency noise characteristics of InP/InGaAs HBTs with various emitter geometries were investigated. A minimum noise figure (Fmin) of 1.51 dB and associated gain (Ga) of 9.6 dB at a frequency of 10 GHz and a DC power consumption of only 1.6 mW (VCE= 1.6 V, IC= 1 mA) at 10 GHz were obtained. The dependence of noise characteristics on bias and geometry is also reported. The dominant noise sources in these HBTs were analyzed and an optimum emitter area of 1.2×20 μm2 was found to present minimum noise figure and equivalent noise resistance.
