MAGNETIC AND STRUCTURAL CHARACTERIZATION OF SPUTTERED FEN MULTILAYER FILMS

The magnetic and structural properties of ferromagnetic FeN thin films, FeN/FeN (ferromagnetic/paramagnetic), and FeN/SiO2 multilayers deposited in a rotational dc magnetron sputter system were investigated. Monolithic films containing congruent-to 2 at. % N2 had 4-pi-M(s) values congruent-to 25 kG. The Fe16N2 phase has been identified by electron microdiffraction in these films. Saturation magnetostriction (lambda-s) has been related to N2 content and can be varied from -3 x 10(-6) to 5 x 10(-6) in a range of compositions where 4-pi-M(s) is > 22 kG. Lamination reduced easy and hard axis coercivity to < 1 Oe and produced single domain configurations in yoke-shaped structures. Lorentz microscopy indicated that the ferromagnetic FeN layers in the FeN/FeN films were exchanged coupled while those in the FeN/SiO2 films were magnetostatically coupled.