Noise Characteristics of AlGaAs/InGaAs/GaAs Pseudomorphic HEMTs with Wide Head T-shaped Gate Fabricated by Optimized Dose Split E-beam Lithography

We report the AlGaAs/InGaAs pseudomorphic HEMT with a wide head T-shaped gate fabricated by optimization of dose split electron beam lithography and selective gate recess etching. The device performances were measured for the fully passivated 0.15 μm gate length HEMT. The maximum extrinsic transconductance was 540 mS/mm. The minimum noise figure measured at 12 GHz under the V_ds = 2 V and I_ds = 22 mA was 0.34 dB with associated gain of 10.22 dB. At 18 GHz, the minimum noise figure was 0.49 dB.