Probing the dielectric, piezoelectric and magnetic behavior of CoFe 2 O 4 /BNT-BT 0.08 composite thin film fabricated by sol-gel and spin-coating methods.

We investigated in this paper a novel bilayer composite obtained by sol-gel and spin coating of the ferroelectric 0.92Na0.5 Bi0.5 TiO3 -0.08BaTiO3 (abbreviated as BNT-BT0.08 ) and ferromagnetic CoFe2 O4 phases, for miniature low-frequency magnetic sensors and piezoelectric sensors. This heterostructure, deposited on Si-Pt substrate (Si-Pt/CoFe2 O4 /BNT-BT0.08 ), was characterized using selected method such as: X-ray diffraction, dielectric spectroscopy, piezoelectric force microscopy, SQUID magnetometry, atomic force microscopy/magnetic force microscopy, and advanced methods of transmission electron microscopy. CoFe2 O4 /BNT-BT0.08 ferromagnetic-piezoelectric thin films show good magnetization, dielectric constant and piezoelectric response. The results of analyses and measurements reveal that this heterostructure can have applications in high-performance magnetoelectric devices at room temperature.