Magnetite epitaxial growth on Ag(001): Selected orientation, seed layer, and interface sharpness

Epitaxial iron oxide layers with different orientations were grown on Ag(001) surface by choosing the appropriate preparation conditions. A film with a hexagonal surface mesh interpreted as (111)-oriented magnetite was formed by reactive deposition of iron in molecular oxygen at room temperature (RT...

Descripción completa

Detalles Bibliográficos
Autores: Lamirand, A.D., Grenier, Stéphane, Langlais, Véronique, Ramos, Aline Y., Tolentino, H.C.N., Torrelles, Xavier, Santis, Maurizio De
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2016
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/215890
Acceso en línea:http://hdl.handle.net/10261/215890
Access Level:acceso abierto
Palabra clave:Magnetite films
Epitaxial growth
Surface x-ray diffraction
Ultrathin transition metal oxide films
Descripción
Sumario:Epitaxial iron oxide layers with different orientations were grown on Ag(001) surface by choosing the appropriate preparation conditions. A film with a hexagonal surface mesh interpreted as (111)-oriented magnetite was formed by reactive deposition of iron in molecular oxygen at room temperature (RT), followed by annealing in UHV. Instead, highly ordered epitaxial layers with P4m symmetry were obtained by a three-step process, optimized through in situ experiments. Following this method, an ultrathin Fe layer was first grown in coherent epitaxy on the substrate and then dosed twice with O2, first at RT and next during annealing. A structural analysis combining low-energy electron diffraction, scanning tunneling microscopy, and accurate surface x-ray diffraction measurements confirmed that these films consist of (001)-oriented magnetite, although with a slight tetragonal distortion induced by the substrate constraints. Both its surface and interface are atomically sharp, an essential requirement for its integration into spintronic based devices.