Effects of processing temperature on the structure and ferroelectric properties of Ba2−xSrxNaNb5O15 thin films by pulsed laser deposition

Ba 2-x Sr x NaNb 5 O 15 thin films have been prepared on Lao 0.05 Sr 0.95 TiO 3 substrates by pulsed laser deposition. Structural and ferroelectric properties of the thin films were dependent on the substrate temperature (T sub ) and Sr concentration. When the oxygen gas pressure (P O2 ) and T sub were fixed at 7.5 mTorr and 700 °C, respectively, the Ba 2-x Sr x NaNb 5 O 15 (x = 0, 0.6, 1.0 and 1.4) thin films exhibited a highly c-axis orientation. The thin films consisted of well-developed grains and exhibited a smooth surface. The c-axis oriented Ba 0.6 Sri 1.4 NaNb 5 O 15 thin film prepared at T sub = 650 °C also exhibited highly c-axis orientation and good P-E hysteresis loop. The remanent polarization (P r ) and coercive field (E c ) were 2P, = 24.9 μC/cm 2 and 2E c = 107 kV/cm, respectively.