Abstract: Polycrystalline BaTiO₃ thin film has been synthesized on Ti-covered silicon substrate at low temperature of 160℃ by hydrothermal method. lts micr-ostructure was dense and homogeneous, with average grain size of about 100 nm by scanning electron microscopic (SEM) observations. It can be found that a multi-laver sructure has, been formed according to the comparisons on X-ray diffraction. (XRD) patterns, SEM morphologies and spread resitance profiles of the samples before and after rapid thermal annealing. And the multilayer structure of cubic BaTiO₃ (a-BT)/amorphous BaTiO_x (a-BT)/TIO_x/Ti/Si has evolved into tetragonal BaTiO₃/TiO_x/Ti/TiSi/Si after annealing.

Key words: hydrothermal method, hydrothermal thin film, BaTiO₃ thin film, microstructure