EFFECTS OF O-2 GAS-PRESSURE IN HEAT-TREATMENT ON SURFACE-MORPHOLOGY AND ELECTRIC PROPERTIES OF FERROELECTRIC BI4TI3O12 THIN-FILMS WITH C-AXIS ORIENTATION

Fabrication of ferroelectric Bi4Ti3O12 thin films was carried out by spin-coating pyrolysis of Bi and Ti naphthenates and successive heat treatment in O-2 gas at various pressures. Heat treatment in O-2 gas at high pressure was effective for the fabrication of c-axis oriented Bi4Ti3O12 thin films with;a smooth surface and improvement of their electric properties. The thin him heat-treated at the O-2 gas pressure of 4.0 x 10(5) Pa was a single phase of Bi4Ti3O12 completely oriented along the c-axis with good ferroelectric properties at room temperature: coercive field of 23 kV/cm, remanent polarization of 1.9 mu C/cm(2), dielectric constant of 45, loss of 0.01 and leakage current density on the order of 10(-9) A/cm(2). The remanent polarization of the thin film was kept constant up to the polarization reversal at 1 x 10(7) cycles.