Influence of the deposition geometry on structural and ferroelectric properties of epitaxial PMN-PT films

摘要

Ferroelectric 0.68Pb(Mg1/3Nb2/3)3-0.32PbTiO3 (PMN-PT) films were prepared on La0.7Sr0.3CoO3 (LSCO) buffered SrTiO3(STO) substrates by pulsed laser deposition (PLD). The influence of different deposition geometries on the structural and ferroelectric properties of the grown PMN-PT films was studied. Whereas an epitaxial growth was observed in a wide temperature range, most of the films showed a secondary phase with a pyrochlore structure in addition to the desired perovskite phase. As a result, high leakage currents were measured in these films due to the secondary phase. A pure perovskite phase growth with promising ferroelectric properties were obtained in PMN-PT PT/LSCO/STO film architectures deposited by on-axis PLD below 600°C. The peak split of the PMN-PT (00ℓ) reflections indicate the coexistence of different structures in these layers.