SOFT MAGNETIC PROPERTIES FOR Fe-Al-N / Si-N MULTILAYERED FILMS

Abstract

This paper presents experimental studies of magnetic and other properties for Fe-Al-N / Si-N multilayered films prepared by two-source rf sputtering. The addition of small amount of Al in Fe-N films was found to be effective in preventing the grain growth of the fine crystal. Magnetic properties and internal stress for multilayered films of Fe-Al-N / Si-N showed a strong dependence on sputtering gas pressure, and it is difficult to obtain soft magnetic Fe-Al-N / Si-N as-deposited films with low internal stress. However, internal stress showed a strong dependence also upon annealing temperature, and after annealing internal stress is reduced. The magnetostriction for Fe-Al-N / Si-N films was found to depend on nitrogen concentration and annealing temperature. The Fe-Al-N (500 Å)/ Si-N (12 Å) multilayered films with high saturation magnetic flux density of 20 kG exhibited a low coercivity 0.1-0.3 Oe, a low internal stress below 2 &tims; 109 dyne/cm2 and a low magnetostriction below 1 × 10-6 after annealed at 550°C.