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arXiv · 1807.02829

Stoichiometry determination of chalcogenide superlattices by means of X-ray diffraction and its limits

Henning Hollermann·Felix Rolf Lutz Lange·Stefan Jakobs·Peter Kerres·Matthias Wuttig
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Abstract

In this paper we explore the potential of stoichiometry determination for chalcogenide superlattices, promising candidates for next-generation phase-change memory, via X-ray diffraction. To this end, a set of epitaxial GeTe/Sb2Te3 superlattice samples with varying layer thicknesses is sputter-deposited. Kinematical scattering theory is employed to link the average composition with the diffraction features. The observed lattice constants of the superlattice reference unit cell follow Vegard's law, enabling a straight-forward and non-destructive stoichiometry determination.

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Henning Hollermann, Felix Rolf Lutz Lange, Stefan Jakobs, Peter Kerres, Matthias Wuttig. 2018-07-08. Stoichiometry determination of chalcogenide superlattices by means of X-ray diffraction and its limits. https://doi.org/10.1002/pssr.201800577

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