TEMPERATURE-DEPENDENCE OF THE ELECTRICAL-PROPERTIES OF SRBI2TA2O9 THIN-FILMS DEPOSITED BY RADIOFREQUENCY MAGNETRON SPUTTERING

Fatigue-free bilayered SrBi2Ta2O9 (SBT) films were successfully prepar ed on Pt/Ti/SiO2/Si substrates by radio-frequency magnetron sputtering . The applied voltage showing the maximum capacitance decreases with i ncreasing temperature. The remanent polarization (2P(r)) and the coerc ive field (2E(c)) obtained for the SBT films were 13 mu C/cm(2) and 12 8 kV/cm at an applied voltage of 5 V at 30 degrees C. The films measur ed at room temperature and 100 degrees C showed fatigue-free character istics up to 10(11) cycles under 5 V bipolar square pulses SBT films s how the retention loss of only 6% after 10 years at 100 degrees C. The leakage current density is less than 4.5 x 10(-7) mu A/cm(2) at an ap plied voltage of 3 V at 75 degrees C. The dominant transport mechanism of SBT films was an interface limited Schottky emission. The Pt/SBT c ontacts have a Schottky barrier height of Phi(B) = 0.8 similar to 1.04 eV.