MAGNETIC-ANISOTROPY IN MULTILAYER FILMS OF METALLIC GLASSES OF FEBSI ALLOYS

The magnetic anisotropy of multilayer films of FeBSi/Si/FeBSi was studied as a function of thickness d of magnetic sublayer of FeBSi and thickness t of nonmagnetic sublayer of Si. The concentration of films varied from Fe//6//6B//3//1Si//3 to Fe//8//3B//1//4Si//3. Samples were obtained by the rf sputtering technique. It is reported that single FeB and FeBSi films show noninduced uniaxial magnetic anisotropy for d less than a critical value d//c of about 120 nm. For multilayer films of two or three magnetic sublayers we observe the noninduced uniaxial anisotropy for the total thickness D of magnetic components larger than 120 nm if t greater than equivalent to 2 nm. For smaller t, however, and still D greater than equivalent to 120 nm, the rotatable anisotropy or uniaxial anisotropy with very large dispersion of easy axis was detected. We believe that the system can be treated as a single film.