Microtexture of magnetite thin films of (001) and (111) orientations on MgO substrates studied by electron-backscatter diffraction

The grain orientation of (001)- and (111)-oriented magnetite thin films grown on MgO substrates (film thickness of 100-400 nm) is analyzed by means of the electron-backscatter diffraction (EBSD) technique. The (001) surface after a short annealing in air (1 min, 250 °C) is characterized by the presence of tiny (diameter of 100-200 nm) misoriented islands, which have an influence on the antiferromagnetic coupling within the film. In the (111)-oriented films, such defects are found to be absent, and the films show a very homogeneous surface. The achieved spatial resolution enables further a cross-section analysis of a 400-nm -thick film with (001) orientation, even close to the interface MgO-magnetite.