X-ray diffraction study of epitaxial CuO nanostructures obtained through post-deposition annealing of Cu on SrTiO$_3$(001)

Orientation, structure and morphology in the early growth stages of CuO films on strontium titanate were studied by synchrotron radiation X-ray diffraction. Nanostructured CuO films were obtained by ex situ heat treatment at 970 K in oxygen flow at ambient pressure after an initial deposition of Cu...

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Detalles Bibliográficos
Autores: Santis, Maurizio de, Langlais, Veronique, Martinelli, Lucio, Mocellin, Tom, Pairis, Sébastien, Torrelles, Xavier
Tipo de recurso: artículo
Estado:Versión enviada para evaluación y publicación
Fecha de publicación:2023
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/344044
Acceso en línea:http://hdl.handle.net/10261/344044
http://arxiv.org/abs/2311.04504v1
Access Level:acceso abierto
Palabra clave:Cupric oxide
Epitaxy
Growth
Multiferroics
Structure
XRD
Descripción
Sumario:Orientation, structure and morphology in the early growth stages of CuO films on strontium titanate were studied by synchrotron radiation X-ray diffraction. Nanostructured CuO films were obtained by ex situ heat treatment at 970 K in oxygen flow at ambient pressure after an initial deposition of Cu on SrTiO$_3$(001) at $10^{-4}$ Pa oxygen pressure using the molecular beam epitaxy technique. These films at low coverages grow forming islands a few tens of nanometers wide, with the [010] direction perpendicular to the substrate surface. Two types of epitaxies are observed, CuO[001]//SrTiO$_3$[100] and CuO[100]//SrTiO$_3$[100], the former being the preferred one. The combination of these epitaxies with the P4mm surface symmetry of the substrate generates 16 different orientations of nanostructures. The lattice constant values obtained from X-ray diffraction are very close to those of bulk tenorite, with the exception of the monoclinic angle $\theta$, which is reduced from 99.54$^\circ$ to 96.76(8)$^\circ$ by the epitaxy constraints. This angle is a key parameter in determining the magnetic properties of CuO.