Simulation of Ring-FinFET and its performance analysis

Abstract

FinFETs have become a potential alternative to MOSFETs as MOSFETs suffer from short channel effects (SCE). Like MOSFETs, FinFETs also face the SCE problems but at very small gate lengths compared to the MOSFETs. Ring or circular structures provide better electrostatics compared to the conventional structures which will be useful to face the SCE. In this work, a novel device structure called, Ring-FinFET(R-FinFET) has been proposed. The performance of the proposed device is studied using the metrics, drive current or ON current (I_ON), OFF current or leakage current (I_OFF), and switching ratio $\left(\frac{I_{ON}}{I_{OFF}}\right)$. Source and drain regions are connected with the channel region through the underlap, and the length of under lap region (L_UN)is adjusted to optimize the $\left(\frac{I_{ON}}{I_{OFF}}\right)$ performance. Apart from these, RF performance metric, unit gain cut-off frequency (f_T) has also been explored. The device operation is tested for different numbers of fins i.e. 4,6,8,10, and 12 fins. Ring FinFET offers better $\left(\frac{I_{ON}}{I_{OFF}}\right)$ ratio, and higher f_T compared to the conventional FinFETs due to the better electrostatic control over the channel.