An Analytic Potential-Based Model for Undoped Nanoscale Surrounding-Gate MOSFETs

An analytic potential-based model for the undoped surrounding-gate MOSFETs is derived in the paper. The model is obtained from rigorously solving Poisson equation together with the drain-current formulation equivalent to Pao-Sah´s double integral that is previously proposed for long-channel bulk MOSFETs. The model consists of an analytic drain-current equation that accounts for both drift and diffusion current components in terms of the potential at the oxide silicon interface and the silicon center of device body evaluated at the source and drain terminals. The model gives a fully self-consistent physical description for the channel potential, charge, and current that is valid for the subthreshold, linear, and saturation regions. The validity of the proposed model has been verified by extensive comparison with the exact numerical integrations and 2-D numerical simulation, which demonstrates model accuracy and prediction capability.