Film Fabrication of Solid Solution of BiFeO3-PbTiO3 by RF-Reactive Sputtering

The magnetic characteristics of solid solution films (BiFeO
₃
-PbTiO
₃
) having both ferromagnetic and ferroelectric characteristics and produced by RF-reactive sputtering are discussed. All samples had a high transmittance in the visible to near-infrared wavelengths with a cut-off wavelength of 410 nm and a refractive index of approximately 2.4 at 900 nm. The spontaneous magnetization 4πMs of these films was 550 G, which is noticeably larger than that of bulk and comparable to that of magnetic garnets and orthoferrites. This spontaneous magnetization decreases with increases in PbTiO
₃
, and can be effectively doubled through post-heat treatment regardless of the PbTiO
₃
concentration.