Temperature dependent microwave noise parameters and modeling of AlGaN/GaN HEMTs on Si substrate

In this paper, we present the temperature dependent microwave noise measurements and modeling of AlGaN/GaN HEMTs on Si substrate over a wide temperature range from -50 to 200degC. The typical noise parameters including minimum noise figure (NF
_min
), noise equivalent resistance (R
_n
), optimum source reflection coefficient (Gamma
_opt
) and associate gain (G
_a
) at different temperatures were measured and their dependencies on temperature were modeled by a linear or a quadratic approximation. The internal noise source coefficients and small signal equivalent circuit parameters (ECPs) were extracted and their variations over temperature were also modeled and discussed. The degradation rate of the noise parameters and internal noise source coefficients of the AlGaN/GaN HEMT on Si with temperature are found to be comparable with the GaN HEMT on SiC and sapphire substrates and also comparable with the GaAs- and InP-based HEMTs. The results demonstrate the great potential of AlGaN/GaN HEMTs on Si for low noise amplifier applications at high temperature.