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

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 (T
_ch
) is smaller than a critical value (T
_{ch, crit}
), the quantum confinement effect may decrease the threshold voltage (V
_th
) roll-off. Therefore, Ge and InGaAs devices may exhibit better V
_th
roll-off than the Si counterpart because of more significant quantum confinement. The scaling of T
_ch
will also increase the effective bandgap due to quantum confinement and hence decrease the BTBT leakage in the Ge and InGaAs devices.