Superior energy storage performance, and fatigue resistance in ferroelectric BCZT thin films grown in oxygen rich atmosphere
Ferroelectric properties of the chemical solution deposited (Ba0.85Ca0.15Ti0.90Zr0.10O3) BCZT thin films in the 200 nm thickness range, grown in air and oxygen rich atmosphere were investigated. Oxygen processed BCZT thin films were found to have very slim hysteresis with high maximum polarization, lower remanent polarization (Pr), much lower coercivity and much higher dielectric breakdown strength. Those properties resulted superior energy storage properties. Oxygen processed BCZT thin films showed energy storage density (ESD) of 64.8 J/cm3 and energy storage efficiency (ESF) of 73% at 2000 kV/cm. Apart from that, the films showed very low leakage current and improved fatigue properties. Oxygen processed virgin BCZT film displayed maximum polarization (Pmax) of 106 μC/cm2 and Pr of 12.9 μC/cm2 whereas, the measured Pmax and Pr on the fatigued film after 1010 switching cycles were 105 μC/cm2 and 13.2 μC/cm2 respectively. BCZT thin films with high ESD, ESF at 2000 kV/cm and with excellent fatigue properties could be considered as the potential candidates for low and intermediate voltage ferroelectric energy storage applications.