Enhanced energy storage and pyroelectric properties of highly (100)-oriented (Pb1−x−yLaxCay)Ti1−x/4O3 thin films derived at low temperature

Highly (100)-oriented (Pb1−x−yLaxCay)Ti1−x/4O3 (x=0.15, y=0.05; x=0.1, y=0.1; x=0.05, y=0.15) thin films were deposited on Pt/Ti/SiO2/Si substrates at a low temperature of 450 °C via a sol-gel route. It was found that all the (Pb1−x−yLaxCay)Ti1−x/4O3 thin films could be completely crystallized and the content of La/Ca showed a significant effect on the electrical properties of films. Among the three films, the (Pb1−x−yLaxCay)Ti1−x/4O3 (x=0.1, y=0.1) thin film exhibited the enhanced overall electrical properties, such as a low dielectric loss (tan⁡δ<0.08) and leakage current (J∼4.6×10−5 A/cm2), a high recoverable energy density (Wre ∼ 15 J/cm3), as well as a large pyroelectric coefficient (p ∼ 190 μC/m2K) and figure of merit (Fd′∼77μC/m2K). The findings suggest that the fabricated thin films with a good (100) orientation can be an attractive candidate for applications in Si-based energy storage and pyroelectric devices.