Characterization of SrBi2Ta2O9 ferroelectric thin films deposited at low temperatures by plasma-enhanced metalorganic chemical vapor deposition

Ferroelectric bismuth-layer SrBi2Ta2O9(SBT) thin films were prepared on Pt/Ti/SiO2/Si substrate by plasma-enhanced metalorganic chemical vapor deposition. The films were crystallized at temperatures between 500 and 600 degrees C. The dielectric constant and dissipation factor of SET films were 320 and 0.04 at an applied frequency of 1 MHz, respectively. The remanent polarization (P-r) and the coercive field (E-c) obtained for a 200 nm thick Sr0.9Bi2.3Ta2.0O9 films deposited at 550 degrees C were 15 mu C/cm(2) and 50 kV/cm at an applied voltage of 3 V, respectively, The leakage current density was about 5.0 x 10(-8) A/cm(2) at 300 kV/cm. The films showed fatigue-free characteristics up to 1.0 x 10(11) switching cycles under 6 V bipolar pulse. (C) 1997 American Institute of Physics.