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 significantly affects the MOS transistor electrostatics. The compact models used to simulate circuits involving III–V MOS transistors must account for this band structure non-parabolicity for accurate results. In this work, we propose a modification 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 confinement 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 efficient 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.