Effects of Addition of Zr and Ti on Sputtered Fe-N Films

The effects of addition of Zr and Ti on iron films containing nitrogen were investigated. Film structures and magnetic properties were studied as functions of the Zr and Ti contents. The coercive force of Fe-N films increased sharply after annealing at about 350°C, while Fe-Zr-N and Fe-Ti-N films retained a small coercive force even after annealing at higher temperatures. The addition of Zr and Ti in small amounts was highly effective in improving the thermal stability of Fe-N because it prevented the growth of iron crystal grains.