Perpendicular magnetic anisotropy
As an alternative texture to the established epitaxial growth of SmCo5 thin films with in-plane alignment of the c-axis, we recently focussed on the preparation of such films with an orientation of the c-axis perpendicular to the film plane. An out-of-plane growth of SmCo5 was obtained by using Al2O3 (0001) substrates with a Ru buffer and applying high deposition temperatures of 700°C. Texture measurements show an epitaxial growth of SmCo5 with two different rotational variants of the SmCo5 basal plane with respect to the substrate for thick films (left figure). With decreasing film thickness, one of the orientations becomes less pronounced, resulting in a single epitaxial relation for films with 20 nm thickness and below. The hysteresis (right figure) displays the highly anisotropic magnetic behavior of a 30 nm thick SmCo5 film when measuring out of the film plane (i.e. parallel to the uniaxial anisotropy axis) and perpendicular to it, together with the extrinsic magnetic properties.
- M. Seifert, L. Schultz, V. Neu, Anisotropy in the c-axis and basal plane of epitaxial NdCo5 films, J. Appl. Phys. 107, 09A711 (2010).
- M. Seifert, V. Neu, L. Schultz, Epitaxial thin SmCo5 films with perpendicular anisotropy, Appl. Phys. Lett. 94, 022501 (2009).