An alternative chemical route for synthesis of SrBi2Ta2O9 thin films

SrBi2Ta2O9 was synthesized by the modified polymeric precursor method using precursor reagents such as carbonate, nitrate, or oxide. The films were deposited onto Pt/Ti/SiO2/Si(100) substrates by spin coating and crystallized at temperatures ranging from 700 to 800 degrees C in air. Microstructural and phase evaluation were followed by grazing incidence x-ray diffraction, scanning electron microscopy, and atomic force microscopy. The films displayed rounded grain structures with a superficial roughness of approximately 10 nm. The dielectric constant values were 362 and 617 for films treated at 700 and 800 degrees C, respectively. The remanent polarization and coercive field were 12.3 mu C/cm(2) and 61 kV/cm and 18.48 mu C/cm(2) and 47 kV/cm for the film treated at 700 and 800 degrees C, respectively. This method generally allows for the use of readily available reagents such as oxides, carbonates, or nitrate as cation sources, with the added advantage that it requires no special apparatus or atmosphere control.