Preparation of Ba2NaNb5O15 thin films by pulsed laser ablation and their characterizations

Ba2NaNb5O15 (BNN) thin films were prepared on Pt substrates by pulsed laser ablation method. We investigated O-2 gas pressure in the growth chamber effects on fabrication of BNN thin films in order to obtain good crystallinity and ferroelectric properties. The characterization of thin films were carried out by X-ray diffraction (XRD), electron probe microanalyzer (EPMA) and observation of ferroelectric hysteresis loops. The thickness of all the BNN thin films were approximately 1.0 mu m All thin films prepared at various O-2 gas pressures showed single phase BNN With a prominent c-axis orientation. The chemical composition of all thin films were nearly equal to the BNN stoichiometry. However, the remanent polarization Pr of BNN thin films was decreased from 0.96 to 0.43 mu C cm(-2) with increasing O-2 gas pressure and could not be improved. (C) 1999 Elsevier Science Limited. All rights reserved.