75 nm Gate Length PHEMT With fmax = 800 GHz Using Asymmetric Gate Recess: RF and Noise Investigation

We report a high maximum frequency of oscillation ( f
_max
) and a current-gain cutoff frequency ( f
_T
) of 800 and 260 GHz, respectively, with pseudomorphic high-electron mobility transistor (PHEMT), using an InGaAs/InAs composite channel and an asymmetric gate recess. This result was achieved with long gate length L
_G
= 75 nm. The RF small signal equivalent circuit (SSEC) was extracted up to 110 GHz. Moreover, noise parameters extraction gives a minimum noise figure (NF
_min
) of 0.8 dB (with associated gain G
_ass
= 16 dB) and 1.8 dB (with associated gain G
_ass
= 11.6 dB) at 40 and 94 GHz, respectively. In this study, the gate leakage current was considered in the SSEC of the transistor ( g
_gf
and g
_df
) and for extraction of the noise parameters.