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arXiv · 1505.02630

Morphology of Superconducting FeSe thin films deposited by co-sputtering and MBE

Eike Venzmer·Alexander Kronenberg·Janek Maletz·Martin Jourdan
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Abstract

The presumably unconventional superconductor Beta-FeSe was deposited by radio frequency sputtering and molecular beam epitaxy (MBE) from two elementary sources. Superconducting thin films were grown in (001)-orientation on MgO(100) and YAlO3(010) substrates. The morphology of the samples was studied and directly related to the superconducting properties of the Beta-FeSe thin films. The MBE grown thin films show microcracks down to the substrate and a roughness of about 100~nm. In contrast, sputter deposited superconducting thin films show a smooth surface with almost no precipitates. In both cases resistive superconducting transitions with critical temperature up to 8.5 K were observed. However, the smoothness of the sputter deposited films is crucial for future surface dependent investigations.

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Eike Venzmer, Alexander Kronenberg, Janek Maletz, Martin Jourdan. 2015-05-11. Morphology of Superconducting FeSe thin films deposited by co-sputtering and MBE. https://arxiv.org/abs/1505.02630

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