The [001]-oriented Pr3+ doped Pb(Mg1/3Nb2/3)O₃-0.30PbTiO₃ (Pr-PMN-PT) thin films with a composition near the morphotropic phase boundary (MPB) were synthesized by a sol⁻gel method. The crystal structure was characterized using X-ray diffraction. It was found that a single perovskite phase was achieved in Pr-PMN-PT thin films annealed at 650 °C for 3 min. The dielectric constant (εr) value was 2400 in 2.5% Pr-PMN-PT thin films at room temperature, 110% higher than that of pure PMN-PT samples. Through 2.5% Pr3+ doping, remanent polarization (Pr) and coercive field (Ec) values increased from 11.5 μC/cm² and 35 kV/cm to 17.3 μC/cm² and 63.5 kV/cm, respectively, in PMN-PT thin films. The leakage current densities of pure and 2.5% Pr-PMN-PT thin films were on the order of 1.24 × 10-4 A/cm² and 5.8 × 10-5 A/cm², respectively, at 100 kV/cm. A high pyroelectric coefficient (py) with a value of 167 μC/m²K was obtained in 2.5% Pr-PMN-PT thin films on Si substrate, which makes this material suitable for application in infrared detectors.
Keywords: dielectric; ferroelectric; pyroelectric; sol–gel; thin film.