Nanoscopic correlations from curve fitting of photoelectron spectromicroscopy data cubes of lead zirconate titanate films

Abstract

Photoelectron spectromicroscopy data cubes with sub-micrometer spatial resolution from a lead zirconate titanate thin film are fitted in each spatial point for several areas investigated, and correlations between the results of the fitting parameters are established, enabling one to suggest that surface band bending manifests also in the case of samples with multiple polarization states. These surface band bendings may be used for preliminary assessment of polarization states by using the contrast in binding energy. However, the individual curve fitting of each spectrum and the analysis of correlations between the derived parameters (binding energies and amplitudes) yields results of deeper significance in deriving the distribution of band bending. This allows in some cases discriminating between the origin of the individual components, assessing charging effects and compensation mechanisms, also enabling one to establish correlations between areas with different polarization. It is found that the major part of the investigated areas consist in regions with outwards polarization and without out-of-plane polarization, with the presence of some isolated metal Pb clusters. On a single area, components attributed to inwards polarization are detected, and their formation occurs at the expense of areas without out-of-plane polarization, mostly for a given proportion of the outwards polarization.