Dielectric and ferroelectric properties of highly (lOO)-oriented (Na_(0.5)Bi_(0.5))_(0.94)Ba_(0.06)TiO_3 thin films grown on LaNiO_3/gamma-Al_2O_3/Si substrates by chemical solution deposition

摘要

A (Na_(0.5)Bi_(0.5))_(0.94)Ba_(0.06)TiO_3 chemical solution was prepared by using barium acetate, nitrate of sodium, nitrate of bismuth, and Ti-isopropoxide as raw materials. A white precipitation appeared during the preparation was analyzed to be Ba(NO_3)_2. We found that ethanolamine is a very effective coordinating ligand of Ba~(2+). A transparent and stable (Na_(0.5)Bi_(0.5))_(0.94)Ba_(0.06)TiO_3 precursor chemical solution has been achieved by using ethanolamine as a ligand of Ba~(2+). (Na_(0.5)Bi_(0.5))_(0.94)Ba_(0.06)TiO_3 films were grown on LaNiO_3/gamma-Al_2O_3Si substrates. Highly (l00)-oriented (Na_(0.5)Bi_(0.5))_(0.94)Ba_(0.06)TiO_3 films were obtained in this work due to lattice match growth. The dielectric, ferroelectric and insulative characteristics against applied field were studied. The conduction current shows an Ohmic conduction behavior at lower voltages and space-charge-limited behavior at higher voltages, respectively. These results indicate that, the (Na_(0.5)Bi_(0.5))_(0.94)Ba_(0.06)TiO_3 film is a promising lead-free ferroelectric film.