Structural and electrical properties of Sr2NaNb4O13 thin film grown by electrophoretic method using nanosheets synthesized from K(Sr2Na)Nb4O13 compound

Sr2NaNb4O13− (SNNO−) nanosheets were exfoliated from the K(Sr2Na)Nb4O13 compound that was synthesized at 1200 °C. The SNNO− nanosheets were deposited on a Pt/Ti/SiO2/Si substrate at room temperature by the electrophoretic method. Annealing was conducted at various temperatures to remove organic defects in the SNNO film. A crystalline SNNO phase without organic defects was formed in the film annealed at 500 °C. However, a SrNb2O6 secondary phase was formed in the films annealed above 600 °C, probably due to the evaporation of Na2O. The SNNO thin film annealed at 500 °C showed a dielectric constant of 74 at 1.0 MHz with a dielectric loss of 2.2%. This film also exhibited a low leakage current density of 9.0 × 10−8 A/cm2 at 0.6 MV/cm with a high breakdown electric field of 0.72 MV/cm.