High-Frequency Microwave Noise Characteristics of InAlN/GaN High-Electron Mobility Transistors on Si (111) Substrate

We report for the first time high-frequency microwave noise performance on 0.17-mu m T-gate In0.17Al0.83N/GaN high-electron mobility transistors (HEMTs) fabricated on Si(111). The HEMTs exhibited a maximum drain current density of 1320 mA/mm, a maximum extrinsic transconductance of 363 mS/mm, an unity current gain cutoff frequency (f(T)) of 64 GHz and, a maximum oscillation frequency [f(max)(U)/f(max)(MSG)] of 72/106 GHz. The product f(max)(U) x V-g = 12.24 GHz.mu m is the highest value ever reported for InAlN/GaN HEMTs on Si substrate. At V-d = 4 V and Vg = -2.25 V, the device exhibited a minimum noise figure (NFmin) of 1.16 dB for 10 GHz and 1.76 dB for 18 GHz. Small variation of NFmin(<0.5 dB) from 8% to 48% with IDmax (100-636 mA/mm) was observed.