High-temperature ferroelectric domain stability in epitaxial PbZr0.2Ti0.8O3 thin films

Using high-resolution atomic force microscopy, we have shown extremely high stability of linear ferroelectric domains in epitaxial PbZr0.2Ti0.8O3 thin films heated up to 735°C, a significant advantage for technological applications. An elevated transition temperature ∼785°C is observed even in relatively thick (91nm) films, despite relaxation of in-plane film-substrate lattice-mismatch-induced strain. We also demonstrate the negligible role of the film surface in determining the written domain-wall configuration, both by direct comparison of the surface roughness with domain-wall position at successive thermal cycles, and by measurements of domain-wall dynamics before and after heating.