Characterization, modeling, and optimization of FinFET MOS varactors

For the first time, nMOS varactors fabricated in FinFET technology were characterized and modeled at microwave frequency. The RF analysis is carried out as a function of the fin width. It is shown that the fin width has nearly no impact on the tuning range of the device, but on the quality factor (Q). Best Q's are obtained for wide fin devices, mainly due to the reduction of the series resistances, and a higher intrinsic conductance