Investigation on aging behavior in ferroelectric materials with perovskite structure

The aging effect in ferroelectric materials plays a central role in the reliability of the related devices. These materials exhibit various kinds of aging behavior. Potassium doped barium titanate was aged below its Curie temperature for different periods of time. The transformation temperature was measured precisely by differential scanning calorimetry. It was observed that the transformation temperature increased with the increase of aging time. The dielectric performance in lanthanum doped ferroelectric lead titanate ceramics after aging was measured. A change of the dielectric spectrum was revealed. Furthermore, the fourier transformation infrared spectroscopy (FTIR) in the (Ba,Mg)TiO3 system during aging was used and it showed unstable FTIR spectra as well. These phenomena are discussed in terms of diffusion of point defects during aging.