Soft Magnetic Characteristics of Multilayered Films with Fe-Al-Si Layers

The magnetic properties of Fe-Al-Si/Fe, Fe-Al-Si/Fe-Si and Fe-Al-Si/Ni-Fe multilayer films prepared using rf sputtering equipment were investigated. These multilayer films had an initial permeability of more than 1000 prior to annealing; the Fe-Al-Si/Fe and Fe-Al-Si/Fe-Si multilayer films in particular had a high saturation flux density Bs of more than 14 kG. The magnetic properties of Fe-Al-Si/Ni-Fe multilayer film were nearly constant and independent of the layer thicknesses. In contrast, the thinner the layers of the Fe-Al-Si/Fe and Fe-Al-Si/Fe-Si multilayer films, the lower was the coercivity. In the latter films, the layer thickness dependence of the coercivity seems to be affected by lattice distortion and the crystal structure rather than by the size of crystallites.