Hexagonal ferrite (h-RFeO₃, R=Y, Dy-Lu) oxide materials are promising candidates for high-density, energy-efficient materials for information processing and storage. Using X-ray diffraction (reciprocal-space mapping), we have investigated the structural quality of LuFeO₃ epitaxial layers grown by pulsed-laser deposition on sapphire substrates with and without platinum interlayers.

The coexisting spontaneous electric and magnetic polarizations make h-RFeO₃ rare-case ferroelectric ferromagnets at low temperature, and in addition the room-temperature multiferroicity and the predicted magnetoelectric effect, makes h-RFeO₃ a potential material for future multiferroic applications. 

Epitaxial strain development during growth of such thin-film structures is an extremely important issue because it has a potential effect on the functional properties of the epilayer: there is therefore considerable scientific and technological interest in the growth of epitaxial thin films in order to tailor their behaviour towards specific materials engineering applications. The epitaxial growth of such h-RFeO₃ thin films and the stabilization of the hexagonal phase depend strongly on the mutual orientation of the layer and substrate lattices (epitaxial orientation) as well as on the epitaxial strain (misfit). 

Using X-ray diffraction (reciprocal-space mapping), we have investigated the structural quality of LuFeO₃ epitaxial layers grown by pulsed-laser deposition on sapphire substrates with and without platinum interlayers. Structural parameters such as the size and misorientation of mosaic blocks have been determined as a function of the thickness of LuFeO3 during growth and for different thicknesses of platinum interlayers up to 40 nm.

Publication

Structure Quality of LuFeO₃ Epitaxial Layers Grown by Pulsed-Laser Deposition on Sapphire/Pt
Bauer, S.; Rodrigues, A.; Horák, L.; Jin, X.; Schneider, R.; Baumbach, T.; Holý, V., Materials, 2020 13 (1), 61 
doi:10.3390/ma13010061