Growth of Ba2−xSrxNaNb5O15 thin film on La0.05Sr0.95TiO3 substrate by pulsed laser deposition

Ba2−xSrxNaNb5O15 thin films were prepared on La0.05Sr0.95TiO3 substrates by pulsed laser deposition. The structural and ferroelectric properties of the thin films depended on substrate temperature (Tsub) and Sr concentration. When Tsub was fixed at 700 °C, the Ba2−xSrxNaNb5O15 (x = 0, 0.6, 1.0, and 1.4) thin films exhibited a high c-axis orientation. The thin films consisted of well-developed grains and exhibited a smooth surface. The c-axis-oriented Ba0.6Sr1.4NaNb5O15 thin film with the lowest Curie temperature also exhibited a high c-axis orientation and a P-E hysteresis loop with a high ferroelectricity at Tsub 650 °C. Thus, its remanent polarization (Pr) and coercive field (Ec) were 2Pr 24.9 μC/cm2 and 2Ec 107 kV/cm, respectively. These values indicate that Ba2−xSrxNaNb5O15 has ferroelectricity in the thin film form.