Two-dimensional analytical threshold voltage roll-off and subthreshold swing models for undoped cylindrical gate all around MOSFET

Analytical, physically-based, models for the threshold voltage and the subthreshold swing of undoped cylindrical gate all around (GAA) MOSFETs have been derived at low drain–source voltage based on an analytical solution of the two-dimensional (2-D) Poisson equation (in cylindrical coordinates) with the mobile charge term included. The new model has been verified by comparison with 3-D numerical simulations of devices with different channel lengths and thickness; the observed agreement with the numerical simulations is quite good.