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arXiv · 1511.06496

Molecular beam epitaxy growth of SrO buffer layers on graphite and graphene for the integration of complex oxides

Adam Ahmed·Hua Wen·Taisuke Ohta·Igor Pinchuk·Tiancong Zhu·Thomas Beechem·Roland Kawakami
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Abstract

We report the successful growth of high-quality SrO films on highly-ordered pyrolytic graphite (HOPG) and single-layer graphene by molecular beam epitaxy. The SrO layers have (001) orientation as confirmed by x-ray diffraction (XRD) while atomic force microscopy measurements show continuous pinhole-free films having rms surface roughness of <1.5 Å. Transport measurements of exfoliated graphene after SrO deposition show a strong dependence between the Dirac point and Sr oxidation. Subsequently, the SrO is leveraged as a buffer layer for more complex oxide integration via the demonstration of (001) oriented SrTiO3 grown atop a SrO/HOPG stack.

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Adam Ahmed, Hua Wen, Taisuke Ohta, Igor Pinchuk, Tiancong Zhu, Thomas Beechem, Roland Kawakami. 2015-11-20. Molecular beam epitaxy growth of SrO buffer layers on graphite and graphene for the integration of complex oxides. https://doi.org/10.1016/j.jcrysgro.2016.04.057

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