Ferroelectric (Pb,Sr)TiO3 Epitaxial Thin Films on (001) MgO for Room Temperature High-Frequency Tunable Microwave Elements

摘要

Ferroelectric Pb0.35Sr0.65TiO3 (PSTO) thin films were grown on (001) MgO by using pulsed laser deposition. Microstructure studies from X-ray diffraction and electron microscopy indicate that the as-grown PSTO films have excellent single crystal quality and good epitaxial behavior with their c-axis oriented perpendicular to the plane of the films. The interface relationships between the PSTO films and MgO were determined to be [100]PSTO//[100]MgO and (001)PSTO//(001)MgO. The high frequency dielectric property measurements (up to 20 GHz) reveal that the as-grown films have a high dielectric constant value above 1420 and very large dielectric tunability above 38% at room temperature. These results suggest that the as-grown PSTO thin films on MgO are a good candidate for developing room-temperature high-frequency tunable microwave elements.