An Explicit Model for Ultra-thin Gate-All-Around Junctionless Nanowire FETs, Including 2D Quantum Confinement.

In this paper, we develop an explicit model to predict the DC electrical behavior in ultra-thin surrounding gate junctionless nanowire FET. The proposed model takes into account 2D electrical and geometrical confinements of carrier charge density within few discrete sub-bands. Combining a parabolic approximation of the Poisson equation, first order perturbation theory for the Schrodinger subband energy eigenvalues, and Fermi-Dirac statistics for the confined carrier density leads to an explicit solution of the DC characteristic in ultra-thin junctionless devices. Validity of the model has been verified with technology computer-aided design simulations. The results confirms its validity for all regions of operation, i.e., from deep depletion to accumulation and from linear to saturation. This represents an essential step toward analysis of circuits based on junctionless nanowire devices.