Crystallization of BaTiO3 thin film at 140°C by metalorganic decomposition hydrothermal method using different precursors

BaTiO3 thin films have been successfully crystallized by hydrothermal treatment of metalorganic decomposition-derived TiO2, BaTiO3 and SrTiO3 gel films in Ba(OH)2 aqueous solution at a low temperature of 140degreesC. BaTiO3 thin film obtained by hydrothermal treatment of TiO2 gel film shows (100) preferred orientation, whereas BaTiO3 thin films obtained by hydrothermal treatment of BaTiO3 and SrTiO3 gel films show (110) preferred orientation. Inductively coupled plasma spectroscopy shows that in BaTiO3 thin film obtained by hydrothermal treatment of TiO2 gel film, Ti is still rich in the films even after 300 min treatment, but the BaTiO3 thin films obtained from BaTiO3 and SrTiO3 gel film are almost stoichiometric. The BaTiO3 thin film obtained by hydrothermal treatment of BaTiO3 gel film shows ferroelectric hysteresis, while that obtained from TiO2 gel film shows paraelectricity.