In this work a de-embedding technique oriented to the evaluation of the load line at the intrinsic resistive core of microwave FET devices is presented. The approach combines vector high-frequency nonlinear load-pull measurements with an accurate description of the reactive nonlinearities, thus allowing one to determine the actual load line of the drain–source current generator under realistic conditions. Thanks to the proposed approach, the dispersive behavior of the resistive core and the compatibility of the voltage and current waveforms with reliability requirements can be directly monitored. Different experiments carried out on a gallium nitride HEMT sample are reported.

A recently proposed technique for the distributed modeling of extrinsic parasitic effects in electron devices is used for the very first time in conjunction with a lumped equivalent circuit model for the intrinsic device.

Nonlinear modeling of 0.1 μm InP HEMTs for W-band applications is considered here, leading to extremely accurate predictions of harmonic distortion and power added efficiency at the fundamental frequencies of 27 and 94 GHz.

The distributed parasitic network is identified through accurate electromagnetic simulations up to the upper frequency limit of the millimeter-wave band (300 GHz), while standard pulsed I/V and S-parameter measurements up to 67 GHz are used for the identification of the intrinsic device model.