Gate-recessed integrated E/D GaN HEMT technology with fT/fmax >300 GHz

We report 1000-transistor-level monolithic circuit integration of sub-30-nm gate-recessed E/D GaN high-electron-mobility transistors with fT and f max above 300 GHz. Simultaneous fT / f max of 348/340 and 302/301 GHz for E- and D-mode devices, respectively, was measured, representing a 58% increase in fT compared with our previous report, due to improved management of RC parasitic delay. Three-terminal E- and D-mode breakdown voltage of 10.7 and 11.8 V, respectively, is limited by gate-drain breakdown.