Preparation of Oriented Barium Titanate Thin Films by Combination of Electrophoretic Deposition with Hydrothermal Treatment

Highly oriented barium titanate (BaTiO3) thin films on Pt substrate were fabricated by combination of elec-trophoretic deposition with hydrothermal treatment. The structure and morphology of thin films were characterized by X-ray diffraction and field-emission scanning electron microscopy. It is found that the titania precursor film, Ba(OH)2 concentration and hydrothermal temperature play crucial roles in the film morphology and orientation. The BaTiO3 thin films with highly (110) preferred orientation can be formed on polycrystalline Pt substrate by appropriate adjustment of the reaction conditions. The orientation parameter f of highly oriented BaTiO3 films was up to 1.00. The films exhibited a smooth and crack-free surface and remained in the layered structure. In situ topotactic transformation and dissolution-crystallization mechanisms were proposed to explain the morphology and orientation of BaTiO3 films during hydrothermal treatment.