Dissipative transport in Multigate silicon nanowire transistors

Most device simulation packages performing quantum transport modeling in thin body Multigate silicon nanowire devices at nanometer scales neglect the electron-phonon interaction, assuming devices operate in the ballistic regime. Here we perform a detailed study on dissipative quantum transport in multigate silicon nanowire transistor including acoustic and optical phonons in detail using non-equilibrium Green's function formalism in uncoupled mode-space approach. We find out that g-type phonons are the most important mechanisms contributing to current reduction in multigate nanowire both in subthreshold and above threshold region for silicon nanowire with 5 nm film thickness. This crucial rule of g-type phonons stay active even for gate lengths below 20 nm, which implies that ballistic models are inadequate to capture the device characteristics of nanometre devices.