On the evaluation theory of C-V measurements on narrow gap semiconductor MIS structures

Abstract

A theoretical model for evaluating experimental capacitance 2014voltage curves on narrow 2014 gap semiconductor (NGS) MIS structures is developed. The features of NGS are taken into account. Demonstrated and discussed is the effect of utilizing Fermi-Dirac statistics, incomplete ionization and recharging of dopants and conduction band nonparabolicity on the behaviour of theoretical C-V curves and interface state density assessment. The analysis so conducted shows that these features must be accounted in C-V analysis of NGS MIS structures. Otherwise incorrect densities of interface states distributed across the band-gap of the semiconductor are obtained.