The authors have developed 0.15 mu m gate length InAlAs/lnGaAs/InP com
posite channel HEMTs with state-of-the-art power performance at 60 GHz
. An output power of 355 mW/mm was obtained with 6.2 dB linear Fewer g
ain and 12% power-added efficiency at a drain voltage of 2.5 V.