90-nm-gated AlGaN/GaN HEMT with fT&fmax of 132GHz&205GHz

AlGaN/GaN high elerton moblity transistors (HEMTs) with about 90 nm gate and 18nm-thick AlGaN barrier were fabricated on SiC substrate. The DC and RF characteristics were mearsured. The device has achieved a maximum drain current density of 1.2A/mm at a gate bias of +1.0V and a peak extrinsic transconductance of about 300mS/mm. The current-gain cutoff frequency (f
T
) reached 132GHz, resulting in a f
T
×L
g
of 11.9GHz·um. The maximum oscillation frequency (f
max
) reached 205GHz.