High-Performance Short-Gate InAlN/GaN Heterostructure Field-Effect Transistors

We fabricated 60-nm-gate InAlN/GaN heterostructure field-effect transistors (HFETs), which had a 6-nm-thick InAlN barrier with an Al composition of 0.86. The devices had a maximum drain current density of 1.34 A/mm and a maximum extrinsic transconductance of 389 mS/mm. The small-signal performance of the devices showed a current-gain cutoff frequency of 172 GHz and a maximum oscillation frequency of 206 GHz. These DC and RF device characteristics were superior to the best values reported for AlGaN (8 nm)/GaN HFETs with the same gate length.