Full-wave modeling device parasitics of sub-millimeter wave HEMTs

Extrinsic parasitic couplings of millimeter-wave and submillimeter-wave high electron mobility transistors (HEMTs) are investigated in the context of THz integrated circuits. More specifically, a multiple-step HEMT parasitic extraction procedure, aimed at improving device performance in the THz band, is developed. A distributed circuit model of lossy substrate is introduced to better approximate the propagation and attenuation through the mesa of the device. Intrinsic and extrinsic effects are considered independently to clearly identify the factors impacting high frequency operation. Numerical examples, involving a submmW HEMT are presented to illustrate the working mechanism of the proposed characterization technique.