RF performance of InAlN/AlN/GaN HEMTs on sapphire substrate

DC and RF performances of an In0.15Al0.85N/AlN/GaN high electron mobility transistor (HEMT) on sapphire substrate with 8.3 nm barrier layer thickness are reported. The device provides a maximum DC current density of 1 A/mm and a peak extrinsic transconductance of 325 mS/mm. A current gain cutoff frequency (FT) of 80 GHz and a power gain cutoff frequency (FMAX) of 130 GHz are obtained for a 110 nm gate length transistor corresponding to the highest reported values from InAlN/AlN/GaN HEMTs grown on sapphire substrate.