关键词: 自组装单层膜, 钛酸钡, 薄膜, 形成机理

Abstract: 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℃ in 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.

Key words: self-assembled monolayers, BaTiO₃, thin film, formation mechanism