A high-power W-band pseudomorphic InGaAs channel PHEMT

We present the process and power microwave measurements of 0.07-μm Al/sub 0.25/Ga/sub 0.75/As/In/sub 0.22/Ga/sub 0.78/As pseudomorphic high-electron mobility transistors (PHEMTs). These devices are passivated and exhibit a Ft of 125 GHz, a current density of 750 mA/mm associated to a high breakdown voltage of 4 V at open channel. Careful power measurements performed at 94 GHz have allowed to demonstrate for the first time an output power of 876 mW/mm associated with 5.7-dB power gain and a power added efficiency of 29% on a PHEMT on GaAs substrate.