Abstract: 83-nm T-shaped gate InP-based In_0.52Al_0.48As/In_0.65Ga_0.35As pseudomorphic high electron mobility transistors (PHEMTs) with excellent DC and RF performance as well as low noise characteristics are reported, including a maximum saturation current density I_dss of 894 mA/mm, a maximum extrinsic transconductance g_m,max of 1640 mS/mm, an extrapolated cutoff frequency f_t of 247 GHz and a maximum oscillation frequency f_max of 392 GHz which were based on the measured S-parameters from 1 to 110 GHz. The minimum noise figure (NF_{m min}) measured by the cold-source method is 1 dB at 30 GHz associated with a gain of 14.5 dB at V_ds of 0.8 V and I_ds of 17 mA. These results were obtained by the combination of increased InAs mole fraction in the channel, gate size scaling, parasitic reduction and the quantization channel. These excellent results make it one of the most suitable devices for millimeter wave (MMW) low noise applications.

Key words: InP, PHEMT, millimeter wave, low noise, on-wafer measurement