Antiferroelectric/ferroelectric composite thin films

PLZT-based antiferroelectric (AFE)/ferroelectric (FE) composite thin films were fabricated by automatic spin coating and crystallized by rapid thermal processing. A computer-controlled automatic spin coat reactor was used to spin composite thin films from acetate precursors with successive layers of FE and AFE composition. Films were spun on platinum-coated silicon substrates and rapid thermal thermally processed at 700/spl deg/C. Composite thin films exhibited improved AFE-type properties including increased dielectric constant (K) and saturation polarization (P/sub sat/) and decreased FE switching field (E/sub F/) compared to typical AFE compositions. X-ray diffraction results indicated that the composite thin films consisted of distinct AFE and FE phases. Modeling of the dielectric properties revealed linear series capacitor behavior within the composite thin films for low electric field conditions; however, nonlinear effects were apparent at high electric fields.