Variable Size and Shape Distribution of Ferroelectric Nanoislands by Chemical Mechanical Polishing

Ferroelectric PbTiO3 nanostructures with lateral dimensions typically below 100 nm are grown on platinized silicon substrates by a chemical solution deposition (CSD) technique. Chemical mechanical polishing allows control of the aspect ratio of the grains, since their initial size distribution is thermodynamically driven (see SEM images; above: as grown, below: polished). Piezoresponse force microscopy measurements on a 15-nm-thick PbTiO3 grain indicate that the polishing step has no detrimental effect on ferroelectric properties.