Impact of microstructure on dielectric properties of (Mg_1/3Nb_2/3)O₃-PbTiO₃ thin films

Abstract

Relaxor thin films of Pb(Mg_1/3Nb_2/3)O₃-PbTiO₃ (PMN-PT) with different microstructures have been grown on platinum-coated silicon substrate using pulsed excimer laser ablation technique. The microstructure of the thin films was found to be strongly influenced by the substrate temperature and the substrate microstructure. An intermediate layer of La_0.5Sr_0.5CoO₃ (LSCO) was deposited on the platinum-coated silicon substrate prior to the deposition of the (PMN-PT) thin films. We found that the both the microstructure and perovskite phase in the PMN-PT thin films could be controlled by monitoring the substrate temperature along with the microstructure of the template layer. The dielectric properties of the films with different microstructure were studied as a function frequency over a wide range of temperatures. A direct impact of the microstructure on relaxor properties has been observed in the present case.