Uncooled detector challenges: Millimeter-wave and terahertz long channel field effect transistor and Schottky barrier diode detectors

The model of long channel unbiased field effect transistor (FET) as mm-wave/THz detector is developed with account of some parasitic effects. The model offered is compared with the other known FET detector models and experimental data. The obtained responsivity (R) and noise equivalent power (NEP) estimations were compared with those for Schottky barrier diode (SBD) detectors. Within the framework of the model, R and NEP values for Si FETs can be determined in all inversion regions. Limits for performance of these detectors have been estimated. It has been shown that with advanced FET technology, the performance of FET mm-wave/THz detectors can be made similar to that of SBD ones or in high frequency range can surpass it. Influence of parasitic effects and detector-antenna matching on detector parameters is discussed. It has been ascertained that FETs can be preferable in some applications due to smaller parasitic effects.