SOFT MAGNETIC-PROPERTIES FOR FE-AL-NB-N-O FILMS

The magnetic and other properties of the fine crystal Fe-N films with the additional elements of AI. Nb and O were investigated. Films were prepared by rf planar magnetron sputtering. The grain size and the lattice spacing were changed by the addition of Al and Nb, and the co-addition of Al and Nb was found to be effective in improving the soft magnetic properties of the films after annealing at 550°C. Introducing oxygen into the sputtering gas of argon and nitrogen increased the nitrogen concentration in the films and was effective in reducing the coercivity of the films. The magnetostriction of the films changed from negative toward positive with increasing nitrogen concentration and crossed zero at the nitrogen concentration where the coercivity took minimum value. The measurement of the hardness of the films revealed that the addition of Al and Nb prevents the recrystallization in Fe films as well as in Fe-N-O films. The (Fe97.5 Ah.1Nbl.4)92 N 602 films exhibited a saturation magnetic flux density of 20 kG, a coercivity of 0.3-0.5 Oe and a hardness Hv above 1000 even after annealed at 550°C without applying magnetic field. © 1990 IEEE