Crystallization of Sr0.7Bi2.3Ta2O9+alpha thin films by chemical liquid deposition

By chemical liquid deposition in which an alkoxide with a carbon number of 4 or smaller was used as raw material, a Sr0.7Bi2.3Ta2O9+alpha (SBTO) thin film was fabricated for use as a ferroelectric memory device for the purpose of decreasing the temperature of crystallization and improving surface morphology. The crystallization process was also examined, Crystallization began when the film was heat treated in oxygen at 650 degrees C. When it was heat treated at higher than 700 degrees C, it showed ferroelectric properties, and the squareness (remanent polarization/saturation polarization) of its hysteresis loop was improved at 800 degrees C. A film heat treated at temperature 650 degrees C was a cluster of fine particles, and a film heat treated at 800 degrees C was a cluster of large particles, A film heat treated at 700 degrees C was a mixture of fine particles and large particles. Therefore, it is concluded that the alkoxide with a carbon number of 4 or smaller as raw material enable the lowering of the heat-treatment temperature and improvement of the surface morphology of SBTO thin films.