It is also found for the as-grown state that along the out-of-plane direction a single ferroelectric domain is formed, and instead the in-plane response reveals a rich domain structure with a domain size of ≈10–30 nm. By characterizing the in-plane piezoelectric response, it is observed that it is anisotropic if the specific orientation, (110), of the SrTiO3 substrate is used. We propose that an out-of-plane single domain is formed due to the presence of an imprint electric field, whereas in-plane domains are formed by non-purely electrostatic interactions as revealed by their relatively large size. Besides, the small but sizeable in-plane anisotropic response is found to result from the in-plane crystallographic configuration, ultimately determined by the selected substrate.
This article is part of the themed collection: Journal of Materials Chemistry C Emerging Investigators
Oxides for new-generation electronics
Vector piezoelectric response and ferroelectric domain formation in Hf0.5Zr0.5O2 films
Huan Tan, Tingfeng Song, Nico Dix, Florencio Sánchez * and Ignasi Fina