Structural and magnetic effects of Ni addition in FeN films

• Published in: Journal of applied physics 2003-04, Vol.93 (8), p.4704-4707
• Main Authors: Zhuge, L. J., Yao, W. G., Wu, X. M.
• Format: Article
• Language: English
• ISSN: 0021-8979; 1089-7550
• DOI: 10.1063/1.1559637

Fe–Ni–N films were prepared on glass substrates by dual ion beam sputtering. The effect of nickel (Ni) addition on the structure, magnetic properties, and thermal stability of Fe–N films was investigated. In the γ′-(Fe,Ni)4N phase, the addition of Ni influences the growth, nitrogen content, and the preferred orientation of the film. The (200) plane of the γ′-phase in the Fe–Ni–N films grows dominantly parallel to the substrate plane with increasing Ni content, indicating the possibility of controlling the crystal orientation. A single γ′-(Fe,Ni)4N phase film with all grains oriented in the (200) direction was actually grown for a Ni content of 21.2 at. %. The coercivity HC of Ni-containing films was lower than that of the Ni-free films. The film with Ni content of 6.7 at. % showed good soft magnetic properties, with HC=0.68 kA/m and MS=2.04 T. The thermal stability, however, was weakened due to the existence of Ni in the Fe–N films.