[Fe80Ni20–O/SiO2]n Multilayer thin films for applications in GHz range

Thin film materials with excellent high-frequency, magnetic and electrical properties are in great demand in modern electromagnetic devices operating in GHz range. In this letter, we fabricated [Fe80Ni20–O/SiO2]n multilayer thin films with different SiO2 interlayer thicknesses (t=0.5–4 nm) and fixed Fe80Ni20–O layer thickness by controlling the sputtering time at room temperature. In these films, the in-plane uniaxial magnetic anisotropy fields can be adjusted in a broad range (from 26 to 107 Oe) by just changing the thickness of each SiO2 interlayer without applying any inducing field. Excellent high-frequency performances in GHz range have been observed in the typical sample.

► [Fe80Ni20–O/SiO2]n multilayer thin films were fabricated by magnetron sputtering. ► In-plane magnetic anisotropy can be adjusted only by the thickness of SiO2 layer. ► Excellent high-frequency characteristics in a broad GHz range can be obtained. ► Promote the application of the multilayer thin films in the GHz range.