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The structural origin of imprint in Pb(Zr,Ti)O3 (PZT) ferroelectric thin films derived by chemical solution deposition with Pt top and bottom electrodes was studied by in-situ high-resolution X-ray specular reflectivity of synchrotron radiation. Global structural parameters of density, thickness, and surface or interface roughness of each component layer in the thin film sample were obtained. No generation of interfacial layers with a different electron density from PZT and no interface roughening were observed at the interfaces of PZT and Pt during imprint. Thus, the results suggest that the imprint effect is more likely a bulk or electronic defects-related phenomenon.

The effects of thermal annealing on Pb(Zr0.3Ti0.7)O3ferroelectric thin film capacitors derived by chemical solution deposition with Pt electrodes were investigated. Sample-averaged structural information of the capacitors with different thermal histories was obtained from fitting the X-ray specular reflectivity using a homogeneous stratified multilayered structure model of Pt∕PZT∕Pt∕TiOx∕SiO2. Electrical measurements showed a remarkable remanent polarization reduction of up to 8.8% and an increase of the dielectric constant at low biases with increasing annealing time from 5to10min. However, no evident change to the fatigue endurance was found except for the reduced initial remanent polarization. The effects of the thermal annealing on the electrical properties of the ferroelectric capacitors are discussed in correlation with the structural changes in the ferroelectric thin films.