Ferroelectric and dielectric properties of manganese-doped Na0.5Bi0.5TiO3 nanocrystalline thin films prepared by metal organic decomposition: A single-layer thickness-dependent study

2at% Manganese-doped Na0.5Bi0.5TiO3 (NBTMn) thin films with single-layer thicknesses ranging from 15 to 45nm/l were deposited on the indium tin oxide/glass substrates by a metal organic decomposition process and spin coating technique. The influence of single-layer thickness on the crystal structure, surface morphology, insulating ability, ferroelectric and dielectric properties was mainly investigated. Compared with the other films, NBTMn film with a single-layer thickness of 30nm/l exhibits the (110)-preferred orientation and dense structure. Also, it shows the enhanced ferroelectricity with a large remanent polarization (Pr) of 38μC/cm2 due to the preferred orientation and low leakage current density. Meanwhile, a high dielectric tunability of 39% for NBTMn with 30nm/l can be observed by varying the measuring applied voltage and frequency. These results indicate that the suitable layer thickness is beneficial to improve the electrical performances of NBTMn thin film.