Highly Preferred Oriented Lead Barium Titanate Thin Films Using Acetylacetone as Chelating Agent in a Sol-gel Process

摘要

Ferroelectric (Pb_1-x,Ba_x)TiO₃ (PB_xT) materials can be synthesized by a sol-gel process incorporating acetylacetone as a chelating agent to form ligand with titanium isopropoxide. It was found that a less cross-linking gel obtained at 120° C and could be converted to nanometric-sized perovskite phase powder. A high purity of (Pb_0.5,Ba_0.5)TiO₃ powder was obtained at 500° C, with a nano-meteric size of about 30-50 nm the specific surface area of 21.91 m²/g. Furthermore, highly oriented PB_xT thin films were obtained by utilizing the as-prepared sol spin-coating on (100) MgO substrate. The oriented films were synthesized from all compositions between x = 0.2 and x = 0.8, at a crystallization temperature of 600° C. In particular, for the Ba content in the range of x = 0.5～0.6, highly preferred (001)/(100) planes were observed.