Effects of annealing on domain-wall contributions to the dielectric properties of PZT thin films

We studied the effects of the annealing process on domain-wall contributions to the dielectric properties of PZT thin films. Two annealing processes, single annealing and layer-by-layer annealing, were used to fabricate PZT thin films. The film thickness was controlled by repeating the spin-coating process. Field-emission scanning electron microscopy and an X-ray diffraction analysis showed the morphological and the structural differences, respectively, between the two films. Based on the analysis of ferroelectric hysteresis loops, we found that PZT thin films fabricated with the single annealing process had larger values of the remanent polarization (P _r) and the coercive field (E _c) than PZT thin films fabricated with the layer-by-layer annealing process. The values for the P _r and the E _c in the two films differed by, at most, 9 μC/cm² and 23 kV/cm. This maximum difference occurred between films that underwent the same number of spin-coating cycles. Using Rayleigh relations, we could explain the differences in ferroelectric properties in terms of domain-wall motion contributions to the dielectric properties.