We investigated the formation of Fe1−xSix phases in the interfacial region of Fe/Si and Fe/FeSi multilayers (MLs). The amount of Fe1−xSix phases formed in Fe/Si MLs depends on Si layer thickness and this amount corresponds to the reduction of saturation magnetization and averaged hyperfine field (Hhf). On the other hand, the reduction of magnetization and averaged Hhf in Fe/FeSi MLs seems not to depend on the FeSi layer thickness; that is, the interface of Fe/FeSi MLs is more stable and a formation of nonmagnetic Fe1−xSix phases is not expected.
