Laser energy density and O2 gas pressure effects on the fabrication of Ba2NaNb5O15 thin films by pulsed laser ablation method

Abstract

Ba2NaNb5O15(BNN) thin films were prepared on Pt substrates by pulsed laser ablation method. We investigated laser energy density and O2 gas pressure 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), scanning electron microscopy(SEM), electron probe micro-analyzer(EPMA) and observation of ferroelectric hysteresis loops. Crystallinity and chemical composition of BNN this films were improved with increasing the laser energy density. Thin films of BNN deposited at the laser energy density of 5.0 J/cm2 and O2 gas pressure of 0.1 Torr showed a good ferroelectric D–E hysteresis loop with Pr = 0.8 μC/cm2 and Ec = 24 k/Vcm at room temperature.