In this study, we demonstrated experimentally that formation of chains and islands of oxygen vacancies in hafnium sub-oxides (HfOx, x<2) leads to percolation charge transport in such dielectrics. Basing on the model of \'{E}fros-Shklovskii percolation theory good quantitative agreement between the experimental and theoretical data of current-voltage characteristics were achieved. Based on the percolation theory suggested model shows that hafnium sub-oxides consist of mixtures of metallic Hf nanoscale clusters of 1-2 nm distributed onto non-stoichiometric HfOx. It was shown that reported approach might describe low resistance state current-voltage characteristics of resistive memory elements based on HfOx.
@article{arxiv.1412.4478,
title = {Percolation conductivity in hafnium sub-oxides},
author = {D. R. Islamov and V. A. Gritsenko and C. H. Cheng and A. Chin},
journal= {arXiv preprint arXiv:1412.4478},
year = {2015}
}