High-linearity high-current-drivability ga0.51in0.49p/gaas misfet using ga0.51in0.49p airbridge gate structure grown by gsmb

A novel structure Ga
_0.51
In
_0.49
P/GaAs MISFET with an undoped Ga
_0.51
In
_0.49
P layer serving as the airbridge between active region and gate pad was first designed and fabricated. Wide and flat characteristics of g
_m
and f
_max
versus drain current or gate voltage were achieved. The device also showed a very high maximum current density (610 mA/mm) and a very high gate-to-drain breakdown voltage (25 V). Parasitic capacitances and leakage currents were minimized by the airbridge gate structure and thus high f
_T
of 22 GHz and high f
_max
of 40 GHz for 1 μm gate length devices were attained. To our knowledge, both were the best reported values for 1 μm gate GaAs channel FETs.