Microstructure and dielectric response of (111)-oriented tetragonal BaTiO₃ thick films prepared by laser chemical vapor deposition

(111)-oriented barium titanate (BaTiO₃) thick films were prepared on Pt-coated Si substrates by laser chemical vapor deposition. The effects of deposition temperature on the orientation, microstructure, and dielectric response of the BaTiO₃ films were investigated. BaTiO₃ films exhibited a significant (111) orientation at deposition temperatures from 930 to 1010K. With increasing deposition temperature from 875 to 1010K, the surface microstructure changed from cauliflower-like to columnar structures with pyramidal caps. The permittivity of a (111)-oriented tetragonal BaTiO₃ film prepared at 980K was 1890 at room temperature and 2600 at the Curie temperature of the film (395K).