Mechanisms of epitaxial growth and magnetic properties of γ′-Fe4N(100) films on Cu(100) -: art. no. 115417

Thin films of iron nitride have been grown on Cu(100) single-crystals by molecular beam epitaxy of Fe in the presence of a beam of atomic N provided by a radio-frequency plasma source. Under the appropriate growth conditions, the films are high-quality, epitaxial, single-phase gamma(')-Fe4N (100). The mechanisms of growth have been studied from the early stages by scanning tunneling microscopy, low energy electron diffraction and Auger electron spectroscopy, that show that the interface with the Cu substrate is very sharp, the intermixing between the growing film and the Cu substrate being limited to few monolayers. The film grows layer by layer. Mossbauer spectroscopy and Kerr effect measurements confirm that the films are magnetic at room temperature, with the easy axis in the plane of the film and parallel to the <100> direction.