Dielectric Property of Epitaxial Films of BaTiO3 Synthesized by Laser Ablation

Epitaxial BaTiO3 films have been synthesized on (100)SrTiO3 at the substrate temperature of 700° C and 100 mTorr of oxygen by the method of laser ablation. The surface of the film is found to be flat with a surface roughness of about 7 nm. For the film with the thickness of 2000 Å, the relative dielectric constant, ε r, exhibits a broad peak at about 150° C; on the other hand, the ε r exhibits a sharp peak at the tetragonal to orthorhombic transition.