Analytical Model of Dual Cavity Nanowire Tunnel FET-based Dielectric Modulated Biosensor

In a general-purpose FET-based dielectric modulated (DM) biosensor, the biomolecule’s presence can be identified by investigating the change in channel conduction. This work demonstrates an analytical model of a Dual Cavity Nanowire (DCN) Tunnel FET-based DM biosensor for label-free biosensing. We opted for a gate-all-around architecture that provides superior gate controllability over the channel charge compared to the planar devices. Using the Poisson equation and Kane’s Model, we framed the analytical model of the electric field, potential and drain current, which is also validated by TCAD results. The permittivity change of the cavity reflects the drain current variation, which could be employed as a sensing parameter to identify a wide range of biomolecules. Further, biomolecules may carry charges (positive/negative), which can be identified using trap charge analysis of the cavity region. Thus, the proposed work provides a detailed insight into sensing the existence of charged and neutral biomolecules within the cavity.