Effect of Annealing Temperature on Minimum Domain Size of Ferroelectric Hafnia

We optimized the annealing temperature of the Hf0.5Zr0.5O2/TiN thin-film heterostructure via a multiscale analysis of the remnant polarization, crystallographic phase, minimum ferroelectric domain size, and average grain size. The remnant polarization and minimum domain size were closely related to the relative orthorhombic and monoclinic phase contents. The minimum domain size and optimum remnant polarization and capacitance were obtained by thermal annealing of Hf0.5Zr0.5O2/TiN/Si at 500 and 600 °C, respectively. The results suggest that the minimum domain size is more important than the sheer magnitude of the remnant polarization because of the retention and fatigue of switchable polarization in ferroelectric nanodevices. This study can contribute to the development of ultralow-power logic transistors and next-generation nonvolatile memory devices.