Beyond Classical Transport: NEGF-Based Unveiling of Ferroelectric Charge-Plasma Vertical Nanowire Dynamics

The theoretical 60 mV/dec subthreshold swing limit of conventional MOSFETs has motivated the exploration of alternative device architectures and materials. This work investigates the effect of embedding a ferroelectric (FE) layer in an ultra-scaled vertical charge-plasma nanowire FET (VNW-FET). Unlike most previously reported FE–nanowire devices that employ channel lengths ≥30–100 nm, thicker FE layers, and are mainly targeted for memory applications, this study analyzes a 15 nm vertical nanowire with a 1.5 nm FE layer in a dopingless charge-plasma configuration. Quantum transport is modeled using mode-space non-equilibrium Green’s function (NEGF) coupled with Schrödinger–Poisson equations, enabling energy-resolved analysis of transmission probability and density of states (DOS). The influence of temperature, FE length, and FE thickness on C–VGSand IDS–VGScharacteristics is examined. Results show that FE integration predominantly affects the ION, where shifts in transmission threshold and DOS redistribution enhance ION. Increasing FE length further improves ION, and the FE/SiO₂ stack enhances the ION/IOFFratio by more than an order of magnitude. The device is also evaluated for NH₃ and H₂ sensing using the Gouy–Chapman–Stern framework.