Self-heating effects in ultra-scaled Si nanowire transistors

In this paper, an atomistic quantum transport simulator coupling electron and phonon transport is used to investigate the influence of self-heating on the performance of ultra-scaled gate-all-around Si nanowire field-effect transistors. By driving not only the electron, but also the phonon population out-of-equilibrium, the developed simulation approach ensures that both current and energy conservation are satisfied, thus giving rise to local variations of the lattice temperature. As a consequence of the increased electron-phonon interactions, it is found that the considered nano-devices operate at about 50% of their ballistic limit, even with a gate length as short as 5 nm. Furthermore, the formation of hot spots close to the drain contact of the transistors is clearly visible with a maximum effective temperature of almost 500 K.