Compact modeling of quantum confinements in nanoscale gate-all-around MOSFETs

Abstract

In this work, a surface-potential based compact model focusing on the quantum confinement effects of ultimately scaled gate-all-around (GAA) MOSFET is presented. Energy quantization with sub-band formation along the radius direction of cylindrical GAAs or thickness direction of nanosheet GAAs leads to significant quantization effects. An analytical model of surface potentials is developed by solving the Poisson equation with incorporating sub-band effects. In combination with the existing transport model framework, charge-voltage and current-voltage formulations are developed based on the surface potential. The model formulations are then extensively validated using TCAD numerical simulations as well as Si data of nanosheet GAA MOSFETs. Simulations of typical circuits verify the model robustness and convergence for its applications in GAA technology.