Growth of ZnO and ZnMgO nanowires by Au‐catalysed molecular‐beam epitaxy

Abstract

AbstractWe have studied oxygen‐plasma assisted molecular‐beam epitaxy growth of ZnMgO nanostructures catalysed by gold. The growth was carried out at temperatures ranging from 350 to 900 °C. Au droplets were prepared by annealing a thermally evaporated Au thin film, or by deposition of Au colloidal particles, or by electron‐beam lithography with a subsequent Au lift‐off deposition process. The resulting nanowires grow at temperatures in the range 700–850 °C with diameter 40–100 nm and with length up to 4 μm. In order to increase nanowire density and reduce tapering, two‐step growth with a ZnO low‐temperature buffer‐layer was successfully implemented. To study Mg incorporation into ZnO nanowires, Zn1–xMgxO nanowires were grown with normalized Mg flux up to 11%. High resolution microscopy, energy‐dispersive X‐ray spectroscopy and X‐ray diffraction reveal that Mg‐doped nanowires grow in single phase with Mg content up to 7.5%. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)