Effect of annealing on microstructure and P–E hysteresis of vanadium doped SrBi2Ta2O9

Abstract

The vanadium modified strontium bismuth tantalate (SBT) was prepared by conventional mixed oxide method using faster firing technique. Ceramics were characterised with the help of scanning electron microscopy and the ferroelectric P–E loop analysis after subsequent annealing. Microstructural analysis suggested a completed densification in undoped SBT after sintering and had not shown modification in microstructure after annealing. However, in the vanadium doped SBT samples the densification is achieved only during the reoxidation or annealing process. Ferroelectric hysteresis could be switched in the doped samples after 24 h of annealing despite the fact that it was not possible to obtain a P–E loop in as sintered and 7·5 h annealed samples of SBTV. The best Pr and Ec (Pr=1·75 μC cm–2, Ec=12·05 kV cm–1) combination was observed with 15% vanadium doping in SBT system which also suggested a great decrease in the coercive field value as observed earlier (∼30 kV cm–1). Current study has shown that improved ferroelectric properties were obtained in the synthesised SBT and V doped SBT even at reduced processing temperatures, which could aid in simplifying the integration of silicon based devices.