Compact modelling of InAlN/GaN HEMT for low noise applications

This paper presents results of high-frequency noise modelling of InAlN/GaN high electron mobility transistors (HEMTs) with different formulations of the minimum noise figure NFmin. Current–voltage characteristics and s-parameters of 0.15 μm gate length and 2 × 75 μm gate width InAlN/GaN HEMTs were measured at room temperature in a wide frequency range (300 MHz to 50 GHz) and bias range (VGS from −4.8 to 1 V and VDS from 0 to 21 V). Both the EEHEMT1 and Angelov GaN compact models yielded excellent agreement for transfer and output characteristics, transconductance gm, and fT, fmax. High-frequency noise parameters NFmin, Rn, ΓOPT of InAlN/GaN HEMT were measured in 8–50 GHz frequency band. Noise formulation within the EEHEMT1 model underestimates the measured NFmin and Rn. The well known three-parameter PRC noise model is in a better agreement with the measured data but neglects the shot noise resulting from the gate leakage. The inductive degenerated source matching method and EEHEMT1 were used to design a single stage LNA operated at 8 GHz frequency. A 10 dB gain with an input reflection of −12 dB with a 2.5 dB of noise factor were obtained at 8 GHz.