1993 年 17 巻 69 号 p. 17-23
Sputtered Fe-Hf-C-N films were investigated to examine the effect of simultaneous addition of C and N elements on the magnetic and structural properties. The as-deposited films having phases of amorphous and bcc a-Fe or near fully crystalline a-Fe phase showed excellent soft magnetic properties upon annealing, reaching the permeability (μ_<eff> at 1 MHz ) of 8200. The thermal stability of the Fe-Hf-C-N films was also found to be excellent; e.g., H_c was less than 0.3 Oe and μ_<eff> was about 4000 for the films annealed up to 700℃. The films exhibited high μ_<eff> of more than 6000 and 4πM_s of about 17 kG in the composition range where the Hf content is about 7 at% and the ratio of [C+N]/[Hf] is around 1.5. The fine grained a-Fe structure, together with finely dispersed Hf(C,N) precipitates which formed at an early stage of crystallization is considered to be one of the main factors for the excellent magnetic properties and thermal stability.
