Layer and Stacking Effects on Transport Properties in Steep-Slope Cold-Metal-Source FETs

Abstract

We investigate the impacts of layer number and heterostructure stacking on the transport of 2D cold-metal-source FETs within the DFT-NEGF framework using our NEGF solver, ATOMOS, which enables electron-phonon coupling analysis. Our simulations demonstrate that optimized NbS2/WS2 stacking reduces the van der Waals gap, enhancing on-current, while additional cold-metal layers introduce density of states near the Fermi level, further improving the on-current. This study presents an effective design strategy for cold-source materials and contacts to achieve steep-slope transport.