Threshold voltage of nanoscale si gate-all-around MOSFET: Short-channel, quantum, and Volume Effects

The threshold voltage (V
_T
) control of gate-all-around (GAA) MOSFETs as an extreme case of multi-gate MOSFETs is studied. After breaking down the components constituting V
_T
into several terms, their relative sizes are compared using TCAD technique and analytical calculation of quantum mechanical problem. As a result, the channel diameter is found to be an important knob to control V
_T
of a GAA MOSFET, which influences on short-channel effect, quantum confinement effect and other effects.