Preparation and Characterization of Tetragonal BaTiO3 Thin Film with Self-assembled Monolayers Technique

Self-assembled monolayers (SAMs) technique based on traditional liquid phase deposition and bio-inspired theory is one of the most promising processes for preparing inorganic thin films. Using octadecyl-trichloro-silane (OTS) as stencil, tetragonal BaTiO3 thin film was successfully prepared on glass wafers in the solution consisting of (NH4)2TiF6, Ba(NO3)2 and H3BO3 with SAMs technique. Hydrophilic characteristic mensuration of glass wafers and photographs of atomic force microscopy (AFM) indicate that the hydrophobe substrate changes into hydrophile by UV iradiation, and a modification of OTS-SAM is changed by UV light. Photographs of metallographic microscope indicate that the surface of BaTiO3 thin film deposited on OTS-SAM is smooth and homogeneous, and an induction of BaTiO3 thin film deposition is directed by OTS-SAM. X-ray diffraction (XRD) and field-emission scanning electron microscope (FE-SEM) results show that the BaTiO3 thin film with well-crystalline tetragonal phase is successfully prepared after annealing at 600 n air for 2h. BaTiO3 thin film grows on glass substrate with a rod-like morphology, the length of the nanowire is in the range from 500nm to 1000nm, which is composed of nanosized grains of around 100nm. The formation mechanism of OTS-SAM and BaTiO3 thin film is carefully discussed.