Single-piece polycrystalline silicon accumulation/depletion/inversion model with implicit/explicit surface-potential solutions

A single-piece analytical equation for the surface potential at the polycrystalline-silicon (poly-Si) gate of a metal-oxide-semiconductor field-effect transistor is presented, which accounts for the poly-accumulation, poly-depletion, and poly-inversion effects. It is shown that the model accurately describes the physical behavior of the surface potentials, gate charge, and capacitance, with smooth transitions, which has been verified with iterative, explicit, and numerical solutions. The proposed model can be used in implicit or explicit surface-potential-based formulations.