Synthesis, Giant Dielectric, and Pyroelectric Response of [001]-Oriented Pr3+ Doped Pb(Mg1/3Nb2/3)O3-PbTiO3 Ferroelectric Nano-Films Grown on Si Substrates

Abstract

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.

Investigation of dielectric and piezoelectric properties in aliovalent Eu3+‐modified Pb(Mg1/3Nb2/3)O3‐PbTiO3 ceramics

“…In addition, for PMN‐PT thin films, the dielectric and ferroelectric properties were improved by Pr 3+ doping. The addition Pr 3+ in PMN‐PT thin films increases the value of remanent polarization and dielectric constant from 11.5 μC/cm 2 and 1140 to 17.3 μC/cm 2 and 2400, respectively . It is known that Eu 3+ shows the similar ionic radius and valence states to Sm 3+ ions.…”

“…The addition Pr 3+ in PMN-PT thin films increases the value of remanent polarization and dielectric constant from 11.5 μC/cm 2 and 1140 to 17.3 μC/ cm 2 and 2400, respectively. 23 It is known that Eu 3+ shows the similar ionic radius and valence states to Sm 3+ ions. Therefore, in this study, Eu 3+ was chosen as dopant in PMN-PT material system to understand if it is a general rule to dope rare earth cation, which has the similar ionic radius to A-site Pb 2+ , in perovskite ferroelectric materials to improve their functionalities.…”

Enhanced dielectric, ferroelectric, and optical properties in rare earth elements doped PMN-PT thin films

“…First, the Ti metal layer of 100 nm in thickness was prepared by DC magnetron sputtering in Ar gas atmosphere [23]. To get pure (100)-oriented PMN-PT thin films, the Ti layer was annealed in a rapid thermal processing (RTP) furnace at 700 ℃ for 1 h. After that, a Pt layer with a thickness of 200 nm was deposited on the TiO 2 /SiO 2 /Si (100) substrate.…”

“…The pyrochlore phase at 2θ = 29.4° is clearly visible in Pr-PMN-0.31PT thin films. With annealing temperature increase to 630 ℃, the pyrochlore phase disappeared, which is caused by the low lead loss during annealing [23]. Figure 1(b) shows the XRD pattern of PMN-xPT thin films with Sm 3+ dopant at different levels of PT.…”

“…For rare earth element doped ferroelectric thin films, a double enhanced dielectric permittivity was obtained in PMN-PT thin films through Pr 3+ ion doping [23]. PMN-PT based thin films also possess many advantages of structure [24], electric and optic properties, such as high transmission [25], high optical damage threshold [20], low material toughness [26], and excellent chemical stability [27], making it as a potential candidate for photoluminescent matrix with RE ions and for optic device integration with powerful conditions.…”