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

Abstract

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 °C. The dielectric constant and dissipation factor of SBT films were 320 and 0.04 at an applied frequency of 1 MHz, respectively. The remanent polarization (Pr) and the coercive field (Ec) obtained for a 200 nm thick Sr0.9Bi2.3Ta2.0O9 films deposited at 550 °C were 15 μC/cm2 and 50 kV/cm at an applied voltage of 3 V, respectively. The leakage current density was about 5.0×10−8 A/cm2 at 300 kV/cm. The films showed fatigue-free characteristics up to 1.0×1011 switching cycles under 6 V bipolar pulse.