HYDROTHERMAL BATIO3 THIN-FILMS ON TI-COVERED SILICON - CHARACTERIZATION AND GROWTH-MECHANISM

Polycrystalline thin films of BaTiO3 with a resistivity of 10(3) Omega cm were fabricated on Ti-covered silicon substrates by a hydrothermal method at temperatures as low as 160 degrees C. The films were formed by submerging the substrates in a 0.5 M Ba(OH)(2) aqueous solution se aled inside an autoclave, heating to 160 degrees C with a saturated va por pressure around 0.8 M Pa, and holding for various periods from 1 u p to 24 h. The film thickness increased as the treatment prolonged wit hin a certain period. The subsequent firing in air at 600 degrees C wa s found to raise the resistivity substantially. The structure and prop erties of the films were characterized by using x-ray diffraction, sca nning electron microscopy, cross-sectional transmission microscopy, Au ger electron spectroscopy, Rutherford backscattering spectroscopy, and spread resistance probing. The film growth mechanism involved in hydr othermal kinetics was discussed. Three ways for hydrothermally synthes izing thick BaTiO3 films have been recommended.