Solution-processed ferroelectric polymer nanocrystals

Since the first demonstrations of ferro- and piezoelectricity in solution-processed ferroelectric polymer thin films research activities have been stimulated in both academia and industry. Several applications have been reported using ferroelectric polymer thin films as bistable polarization switches in memory devices or as transducers in (micro-)electromechanical devices. In light of the continuing miniaturization of such devices, nanoscaled structures of ferroelectric polymers such as nanomesas are attracting increasing interest. However, nanopatterning ferroelectrics, to develop stable and reliable ferroelectric nanomesas remains challenging. In this work, we demonstrate the fabrication of solution-processed ferroelectric polymer nanocrystals, i.e. ferroelectric nanomesas, and verify their ferroelectric activity. By using the ferroelectric copolymer of vinylidene fluoride and trifluoroethylene (P(VDF-TrFE)), we are able to isolate crystalline domains. Morphology, molecular conformation, (nano-)mechanical and electromechanical properties of the nanocrystals are measured, yielding comparable results to those observed in uniform, continuous thin films. Therefore, synthesizing self-assembled ferroelectric polymer nanocrystals from polymer solution by spin-casting represents a promising approach for the realization of ferroelectric nanomesas. © 2023