Ferroelectric (Pb, Sr)TiO_3 epitaxial thin films on (001) MgO for room temperature high-frequency tunable microwave elements

摘要

Ferroelectric Pb_(0.35)Sr_(0.65)TiO_3 (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 34% 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.