IN-SITU PREPARATION OF POLYCRYSTALLINE BATIO3 THIN-FILMS ON SILICON BY HYDROTHERMAL METHOD

Insulating cubic BaTiO3(c-BT) polycrystalline thin films were synthesi zed on titanium covered silicon substrates using a novel low temperatu re technique called hydrothermal method. The films were hydrothermally formed by submerging the substrate in a 0.5M Ba(OH)(2) aqueous soluti on sealed inside an autoclave, heating to 160 degrees C with saturated vapor pressure around 0.8MPa and holding for various periods ranging from 1 to 9 hours. The surface of as-treated samples was dense, smooth pinhole-free with high homogeneity. Scanning electron microscopic (SE M) morphology showed the 6-hour-prepared films were composed of submic rocrystallines with grain Size varied from 100 to 300nm in diameter. T he films were characterized by X-ray diffraction (XRD), SEM, cross-sec tional transmission electron microscopy (XTEM), Auger electron spectro scopy (AES) and Rutherford backscattering spectroscopy(RBS) analyses. The experimental results proved that hydrothermal method will become a valuable approach for fabricating perovskite oxide films which is of great significance.