Hall measurement of ultra thin vanadium dioxide thin films

TL;DR

This study investigates the temperature-dependent Hall effect in ultra-thin VO₂ films, revealing electron-dominated conduction, a semiconducting band gap, and phase inhomogeneity, advancing understanding of their electronic properties.

Contribution

It provides detailed Hall measurements of ultra-thin VO₂ films, identifying charge carrier behavior, band gap, and phase inhomogeneity, which were not previously characterized in such films.

Findings

Electrons are the main carriers in both phases.

Resistivity decreases with temperature due to increased carrier density.

The films have a band gap of approximately 0.40 eV.

Abstract

In this work, we present the investigation of temperature dependent hall measurement of the ultra thin VO$_2$ films grown on Si/SiO$_2$ substrate. Experimental results suggest that electrons are the predominant carrier both in the semiconducting and metallic phases. The decrease of the resistivity with increasing temperature is mainly caused by the increase in the number density of charge carriers. The temperature dependence of the carrier concentration indicates the VO$_2$ films has a band gap of 0.40$\pm$0.09 $ev$ in the semiconducting phase. Analysis of hall effect data based on a composite cube model suggests that the sample has some untransitional phase with a length that is 1/4 of the grains.