Multiferroic BaTiO3–CoFe2O4–BaTiO3 thin films were synthesized by spin coating of Co(NO3)2–Fe(NO3)3 and Ba(OAc)2–Ti(i-OPr)4 dissolved in a mixture of acetic acid and dimethylformamide. Stepwise thermaltreatment at 200, 400 and 800◦C led to the desired phases. The phase formation process was monitoredby thermoanalytic, XRD, IR and Raman measurements. SEM was used to characterize the structure and thickness of each layer. Two samples with different thicknesses of perovskite and spinel layers are discussed. Sample 1 consists of 120 nm CoFe2O4 between two 70 nm BaTiO3 layers. For sample 2, the 90 nm BaTiO3 top and bottom layers are enclosing 220 nm CoFe2O4. The surface qualities were determined byAFM indicating rms roughness values of about 4 nm. Magnetic investigations reveal slightly anisotropicbehavior. Polarization measurements show hysteresis loops (Ps(max)= 29 µC cm−2; Ps(max)= 17 mC cm−2) with switching peaks at the corresponding coercive fields.
BaTiO3–CoFe2O4–BaTiO3 trilayer composite thin films prepared bychemical solution deposition