Improved microwave noise performance in 0.15μm AlGaN/AlN/GaN HEMTs on silicon

High-frequency microwave noise performances (2 GHz to 19 GHz) were investigated on AlGaN/AlN/GaN High Electron Mobility Transistors (HEMTs) with 0.15 μm T-gate fabricated on high resistivity 4-inch Silicon. The HEMTs exhibited maximum drain current density (I_Dmax) of 830 mA/mm, maximum extrinsic transconductance (g_mmax) of 353 mS/mm, unity current cut-off frequency (f_T) of 65 GHz and maximum oscillation frequency (f_max) of 125 GHz. At V_DS=6V and I_D=188mA/mm, the devices exhibited a minimum noise figure (NF_min) of 0.59 dB at 10 GHz and 1.5 dB at 18 GHz. The NF_min for 10 GHz is the lowest reported value in the literatures for conventional AlGaN/GaN HEMTs on Si substrate. No significant change in microwave noise performance has been observed in the devices over for a wide range of I_D (22 mA/mm to 500mA/mm) and V_D (3V to 16V).