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A series of PbZr0.58Ti0.42O3 (PZT) thin films with various Bi3.25La0.75Ti3O12 (BLT) buffer layer thicknesses were deposited on Pt/TiO2/SiO2/p-Si(100) substrates by RF magnetron sputtering. The X-ray diffraction measurements of PZT film and PZT/BLT multilayered films illustrate that the pure PZT film shows (111) preferential orientation, and the PZT/BLT films show (110) preferential orientation with increasing thickness of the BLT layer. There are no obvious diffraction peaks for the BLT buffer layer in the multilayered films, for interaction effect between the bottom BLT and top PZT films during annealing at the same time. From the surface images of field-emission scanning electron microscope, there are the maximum number of largest-size grains in PZT/BLT(30 nm) film among all the samples. The growth direction and grain size have significant effects on ferroelectric properties of the multilayered films. The fatigue characteristics of PZT and PZT/BLT films suggest that 30-nm-thick BLT is just an effective buffer layer enough to alleviate the accumulation of oxygen vacancies near the PZT/BLT interface. The comparison of these results with that of PZT/Pt/TiO2/SiO2/p-Si(100) basic structured film suggests that the buffer layer with an appropriate thickness can improve the ferroelectric properties of multilayered films greatly.

PbZr0.58Ti0.42O3 (PZT) ferroelectric thin films with Bi3.25La0.75Ti3O12 (BLT) buffer layer of various thickness were fabricated on Pt/TiO2/SiO2/p-Si(100) substrates by rf-magnetron sputtering method. The pure PZT film showed (111) preferential orientation in the XRD patterns, and the PZT/BLT films showed (110) preferential orientation with increasing thickness of the BLT layer. There were no obvious diffraction peaks for the BLT buffer layer, for its thin thickness in PZT/BLT multilayered films. There were the maximum number of largest-size grains in PZT/BLT(30 nm) film among all the samples from the surface images of FESEM. The growth direction and grain size had significant effects on ferroelectric properties of the multilayered films. The fatigue characteristics suggested that 30-nm-thick BLT was just an effective buffer layer enough to alleviate the accumulation of oxygen vacancies near the PZT/BLT interface. The comparison of these results suggests that the buffer layer with an appropriate thickness ...

The PREISACH approach is applied to provide further insight into the physical mechanisms of ferroelectric operation and degradation. Starting from the discussion on experimental determined PREISACH distribution, analytical formulae for the various fatigue cycles is deduced. Considerations about the uniform expression respects to the cycle numbers, and the ways to describe it are also made. The agreement between the measure and calculation illustrate such a description to be an efficient tool to model the ferroelectric fatigue behavior. This approach is also utilized to examine nature of cycling degradation, the excursion of defect charge and their effect on domain pinning is characterized quantificationally. This model seems quite appropriate to relate the degenerative loops with the actual defect structure.

An innovated and the typical one-mask-patterned integrated ferroelectric capacitors process with Sol-Gel deposited technique are investigated. The key improvement for the innovated route is that the ferroelectric film was etched in non-crystalline phase. Due to the etching damage, the ferroelectric and fatigue properties of the typical integrated capacitor were degradation, and the desquamation of top electrode was also existed. The uniformly Pt/PbTiO3/PbZr0.3Ti0.7O3/PbTiO3/Pt (Pt/PT/PZT/PT/Pt) integrated ferroelectric capacitor arrays with explicit and smooth side-wall were obtained by the innovated integrated process. The XRD results exhibit that the innovated integrated ferroelectric capacitor was well crystallized, and the ferroelectric film belongs to the perovskite phase. The etching degradation on the properties of the innovated integrated ferroelectric capacitor was reduced to minimize, confirmed by SEM, EDX results, the ferroelectic and fatigue properties. The innovated process can be co...