FERROELECTRIC PROPERTIES OF HYDROTHERMALLY PREPARED BATIO3 THIN-FILMS ON SI(100) SUBSTRATES BY LOW-TEMPERATURE PROCESSING

Polycrystalline BaTiO3 thin films were prepared hydrothermally on Ti-deposited Si(100) substrates at 220 degrees C for 24 h using a 2.0 N Ba(OH)(2) solution. The surface morphology of the films observed by scanning electron microscopy indicated that the films were crack-free and uniform, and the thickness of the cross section was about 350 nm. From the AES analysis of the films, it was found that stoichiometrically uniform films exist and serious interdiffusion in the interface region did not appear. The dielectric constant and dielectric loss at 10 kHz at room temperature were about 150-200 and below 0.08, respectively. The capacitance dependence on applied de voltage exhibited maximum value at -0.9 V and breakdown did not occur in the measurement range. The hydrothermally prepared films showed ferroelectric behavior and that was found by us for the first time. The measured value of remanent polarization (P-r) and coercive field (E(c)) amounted to 21.6 mu C/cm(2) and 26 kV/cm, respectively.