Studies on the relax behavior of SrBi2Ta2O9 thin films

Relax behavior of SrBi2Ta2O9 thin film is investigated. In very short-time scale (less than 10 mu s), the relaxation curve follows the characteristics of the voltage change, due to the signal and polarization delay. After 100 mu s's relax time, the curve tends to be linear in logarithmic time axes, suggesting that the decay of retained polarization is logarithmic damping. Applied voltage and probe polarity can influence the relaxation curve. Higher applied voltage causes higher decay rate. This can be attributed to the depolarization field, which aggravates the retained polarization's decay. Different probe polarities cause different curves, probably due to the asymmetry of the top electrode and the bottom electrode.