Beneficial effects of quantum confinement on Ge and InGaAs ultra-thin-body NMOSFETs

摘要

This work investigates the impacts of quantum confinement on the short-channel effect and band-to-band-tunneling (BTBT) of UTB Ge and InGaAs NMOS devices using derived analytical solution of Schrödinger equation verified with TCAD simulation. Our study indicates that, when the channel thickness (Tch) is smaller than a critical value (Tch, crit), the quantum confinement effect may decrease the threshold voltage (Vth) roll-off. Therefore, Ge and InGaAs devices may exhibit better Vth roll-off than the Si counterpart because of more significant quantum confinement. The scaling of Tch will also increase the effective bandgap due to quantum confinement and hence decrease the BTBT leakage in the Ge and InGaAs devices.