Epitaxial growth of SrRuO₃ thin films by RF sputtering and study of surface morphology

Abstract

We report on the epitaxial growth of SrRuO₃ (SRO) thin films on Pt (111)/γ-Al₂O₃ (111) nSi (111) substrates. The grown thin films are crystalline and epitaxial as suggested by RHEED and XRD experiments. With the use of γ-Al₂O₃ (001)/nSi (001) and γ-Al₂O₃ (111)/nSi (111) substrates, crystalline but not epitaxial films have grown successfully. This result implies that lattice mismatch between nSi and SRO prevents the epitaxial growth of SRO film directly on nSi. However, the buffer Pt (111) layer mitigates lattice mismatch that provides to grow epitaxial film on nSi of quality. Morphological study shows a good surface with moderate roughness. Film grown at 700°C is smoother than the film grown at 750°C, but the variation of temperature does not affect significantly on the epitaxial nature of the films.

Keywords

RF-sputtering / molecular beam epitaxy (MBE) / X-ray diffraction (XRD) / epitaxial Al₂O₃

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Acknowledgments

This work was supported by Toyohashi University of Technology, Tempaku-cho, Toyohashi, Aichi 441-8580, Japan.

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2014 Higher Education Press and Springer-Verlag Berlin Heidelberg