Magnetic Anisotropy and Permeability of Fe-Zr-N Thin Films

The effects of heat treatment on the soft magnetic properties and crystalline structure of Fe-Zr-N thin films prepared by rf magnetron sputtering were investigated. Results show that appropriate heat treatment yielded films with an ultra-fine grain structure, excellent soft magnetic properties, and thermal stability at temperatures above 500 °C. The thermal behavior of the film uniaxial anisotropy induced by heat treatment in a dc magnetic field was also studied. The anisotropy field Hk showed rapid reversible relaxation in the first few minutes of heat treatment in a magnetic field parallel to the hard axis. On the other hand, little variation was observed in Hk and the permeability when the sample was heat-treated without a magnetic field applied.