Low temperature deposition of BiFeO3 films on Ti foils for piezoelectric applications

Abstract Predominantly (100)-oriented BiFeO3 films with excellent ferroelectric and piezoelectric properties were successfully fabricated on Ti foils via RF-magnetron sputtering at 450 °C. Well-saturated P-E loops with a high remnant polarization (Pr ~72 μC/cm2) and a large built-in field (~145 kV/cm) were observed in the BiFeO3 films. A large transverse piezoelectric coefficient (|e31,f| ~ 2.2 ± 0.2 C/m2) and a decent dielectric property (er~260–270, tanδ~1.6–2.0%), together with a remarkable fatigue-resistance (~1.1% loss of |e31,f| after 1.2 × 106 piezoelectric actuation cycles) were demonstrated in patterned BiFeO3-Ti cantilevers. These results indicate a great potential of BiFeO3 films as piezo-active components in metal-based micro-electro-mechanical systems (MEMS).