Effect of ferroelectric switching time on fatigue behaviors of (117)- and (00l)-oriented (Bi,La)4Ti3O12 thin films

The effect of switching characteristics on the ferroelectric fatigue behaviors of the La-substituted Bi4Ti3O12 (BLTO) capacitors were investigated. The parameter of switching time (ts) for the fabricated BLTO capacitor was found to be dependent on the crystallographic orientations of prepared BLTO films and the capacitor size. It was clearly demonstrated that the BLTO capacitors experienced the fatigue degradation only when the switching pulse width was longer than ts. In particular, these behaviors were apparently observed in the full-switching regime where a sufficiently large field was applied to the ferroelectric capacitors. For the first time, the fatigue behaviors of BLTO films with two different crystallographic orientations of (117) and (00l) were intensively studied under various measuring conditions.