Synthesis and properties of ferroelectric SrBi2Ta2O9 powder and films prepared by a sol-gel process

Crystalline powder with particle size <200 nn and films with thickness <350 nm of SrBi2Ta2O9 (SBT) with a layered perovskite structure were prepared by a sol-gel technique using an alkoxide-carboxylate precursor solution. The structural variation of the SET powder with annealing temperature was studied by thermogravimetry (TGA), differential thermal analysis (DTA), Fourier transform infrared (FT-IR) spectroscopy and X-ray diffractometry (XRD). The lowest temperature for the formation of a pure perovskite phase of SET was found to be 650 degrees C. The average crystallite diameter in the films annealed at 650 degrees C was 70 nm. The ferroelectric hysteresis loop of the SET films was also obtained. (C) 1999 Elsevier Science B.V. All rights reserved.