Epitaxial ferroelectric Y-doped HfO2 film grown by the RF magnetron sputtering

Abstract

YO1.5-doped HfO2 films were deposited on yttria-stabilized zirconia substrates by RF magnetron sputtering at room temperature and under various atmosphere conditions. The deposited films were treated by rapid thermal annealing under both O2 and N2 flows. Epitaxial films with the orthorhombic phase, which is expected to exhibit ferroelectricity, are obtained under all conditions. The deposition in Ar atmosphere provided good ferroelectricity, while the deposition with O2 resulted in a low breakdown voltage inhibiting ferroelectricity. Current density–voltage characteristics show a significant increase in leakage current by the deposition in atmosphere containing O2 and also annealing under O2 flow. These results indicate that the treatment in atmosphere containing O2 leads to the degradation of insulation properties.