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arXiv · 1708.06979

In situ monitoring of atomic layer epitaxy via optical ellipsometry

Fryderyk Lyzwa·Premysl Marsik·Vladimir Roddatis·Christian Bernhard·Markus Jungbauer·Vasily Moshnyaga
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Abstract

We report on the use of time-resolved optical ellipsometry to monitor the deposition of single atomic layers with subatomic sensitivity. Ruddlesden-Popper thin films of SrO(SrTiO3)n=4 were grown by means of metalorganic aerosol deposition in the atomic layer epitaxy mode on SrTiO3(100), LSAT(100) and DyScO3(110) substrates. The measured time dependences of ellipsometric angles, ${\Delta}(t)$ and ${\Psi}(t)$, were described by using a simple optical model, considering the sequence of atomic layers SrO and TiO2 with corresponding bulk refractive indices. As a result, valuable online information on the growth process, the film structure and defects were obtained. Ex situ characterization techniques, i.e. transmission electron microscopy (TEM), X-ray diffraction (XRD) and X- ray reflectometry (XRR) verify the crystal structure and confirm the predictions of optical ellipsometry.

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Fryderyk Lyzwa, Premysl Marsik, Vladimir Roddatis, Christian Bernhard, Markus Jungbauer, Vasily Moshnyaga. 2017-08-23. In situ monitoring of atomic layer epitaxy via optical ellipsometry. https://doi.org/10.1088/1361-6463/aaac64

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