Analytical Physics-Based Modeling of Electron Channel Density in Nanosheet and Nanowire Transistors

We propose a general physics-based approach for an accurate analytical calculation of the channel charge density in field-effect transistors as a function of the external gate biases. This approach is based on consistent consideration of basic electrostatic equation as a balance of electric and chemical potentials which allows us to obtain in a unified way the explicit analytic expressions continuously describing the subthreshold and above threshold regions in the nanosheet (symmetric and asymmetric) and nanowire FETs. Two conceptually different definitions of phenomenological threshold voltage are consistently introduced and discussed.