Parasitics-Aware Quantum Transport Simulation of Stacked Si Nanosheet LGAA-nFETs for Sub-2 nm Node RF Applications

This work presents a comprehensive quantum transport modeling and simulation framework to evaluate parasitic effects and radio frequency (RF) performance in stacked silicon (Si) nanosheet (NS) lateral gate-all-around (LGAA) nFETs targeting the sub-2 nm technology node. Leveraging the non-equilibrium Green’s function (NEGF) method, the proposed framework integrates detailed modeling of parasitic resistances (Rpara) and capacitances (Cpara) to enable a holistic analysis of both intrinsic and extrinsic figures-of-merit, including transconductance (gm), output conductance (gd), cutoff frequency (fT), and maximum oscillation frequency (fmax). The effects of nanosheet geometry, crystal orientations, and dual-k spacers on high-frequency performance are systematically investigated. The analysis reveals key design trade-offs, with optimized device configurations yielding fT exceeding 400 GHz and fmax approaching 1.2 THz. These findings highlight the potential of stacked NS LGAA-nFETs for future millimeter-wave and terahertz applications, providing critical insights into parasitics management and quantum-transport-aware design strategies at advanced CMOS nodes.