Thin Films of Layered-Structure (1-x)SrBi2Ta2O9-xBi3TiTaO9 Solid solution for Ferroelectric Random Access Memory Devices

{0.75SrBi2Ta2O9-0.25Bi3 TiTaO9} (SBT-BTT) thin films have been prepared by using the modified metalorganic solution deposition (MOSD) technique. The microstructure and ferroelectric properties of SBT-BTT thin films were studied. The SBT-BTT thin films were produced at 750degC . The surface morphology of SBT-BTT thin films showed more uniform grain distribution. The grain size and surface roughness of SBT-BTT films showed significant enhancement with an increase in annealing temperature. It is found that SBT-BTT thin films have good ferroelectric property. The measured remanent polarization values (2Pr) for SBT-BTT, SBT and BTT capacitors were 15muC/cm2, 7.5muC/cm2 and 4.8muC/cm2, respectively. The coercive field (Ec) for SBT-BTT capacitors was 50kV/cm. More importantly, the polarization of SBT-BTT capacitors only decreased 5% after 1011 switching cycles at a frequency of 1MHz. The improved microstructural and ferroelectric properties of SBT-BTT thin films compared to SBT suggested the possibility for ferroelectric devices applications

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