Impact of Quantum Confinement on Short-Channel Effects for Ultrathin-Body Germanium-on-Insulator MOSFETs

摘要

This letter investigates the impact of quantum confinement (QC) on the short-channel effect (SCE) of ultrathin-body (UTB) and thin-buried-oxide germanium-on-insulator (GeOI) MOSFETs using an analytical solution of Schrödinger equation verified with TCAD simulation. Our study indicates that, although the QC effect increases the threshold voltage $(V_{rm th})$ roll-off when the channel thickness $(T_{rm ch})$ is larger than a critical value $(T_{{rm ch}, {rm crit}})$, it may decrease the $V_{rm th}$ roll-off of GeOI MOSFETs when the $T_{rm ch}$ is smaller than $T_{{rm ch}, {rm crit}}$. Since Ge and Si channels exhibit different degrees of confinement and $T_{{rm ch}, {rm crit}}$, the impact of QC must be considered when one-to-one comparisons between UTB GeOI and Si-on-insulator MOSFETs regarding the SCE are made.