We thus suggested investigating a larger number of lead titanate ferroelectric nanoislands in parallel in order to obtain sufficient displacement charges to overcome the detection noise. Our previous experiments of template-mediated growth by electron-beam lithography paved the way for large numbers of ferroelectric nanoislands with long-range ordering and a narrow size distribution. These results were complemented by our recent experiments on the embedding of unregistered ferroelectric nanoislands into a low-k dielectric matrix of a spin-on glass that was polished down to deposit macroscopic top electrodes without electrical shorts between the nanoislands.

In this contribution we now open the door to a study of thousands of well-registered and almost identical ferroelectric nanoislands in parallel as we embed those ordered structures into a low-k dielectric matrix and show qualitative ferroelectric functionality on individual nanostructures by means of piezoresponse force microscopy. The chemical mechanical polishing helps tuning the overall thickness and yields a planarized surface that eliminates topography effects in piezoresponse force microscopy.

In what is to come, the deposition of macroscopic top electrodes will allow for averaging the electronic properties of ferroelectric nanocapacitors far below 100 nm to explore coercivity, permittivity and polarization as a function of lateral dimensions. About the authors