A compact model for III–V nanowire electrostatics including band non‑parabolicity

Abstract

The III–V materials have a highly non-parabolic band structure that signifcantly afects the MOS transistor electrostatics. The compact models used to simulate circuits involving III–V MOS transistors must account for this band structure nonparabolicity for accurate results. In this work, we propose a modifcation to the energy dispersion relation to include the band structure non-parabolicity in a way suitable for compact models. Unlike the available non-parabolic energy dispersion relation, the one proposed here is simple and includes the non-parabolicity in both confnement and transport directions. The proposed dispersion relation is then used to model the electrostatics of III–V nanowire transistors. The proposed model is scalable to a higher number of sub-bands and computationally efcient for circuit simulators. The model is also validated with the data from a 2D Poisson–Schrödinger solver for a wide range of nanowire dimensions, III–V channel materials, and found to be in excellent agreement with the simulation data.