FERROELECTRICITY OF BI2SRTA2O9 SINGLE-CRYSTALS GROWN BY THE SELF-FLUXMETHOD

Ferroelectric hysteresis of a Bi2SrTa2O9 single crystal, a promising c andidate for ferroelectric random access memories (FeRAM), was observe d at 200 degrees C. This single crystal, grown by the self-flux method , has a composition characterized as BixSryTa2O9 (x = 1.91 +/- 0.05, y = 1.27 +/- 0.08). Observing the optical anisotropy of the c-plane, it was found that this material has a Curie temperature (T-c) higher tha n 250 degrees C. Measuring the electrical properties on the c-axis and in the c-plane, it was confirmed that this material has electrical an isotropy. Furthermore; the domain motion of the crystal was observed u nder an electric field using a high-resolution charge-coupled-device ( CCD) microscope system.