Structural and electrical characterization of Hf_0.5Zr_0.5O₂ thin films crystallized by rapid thermal annealing

The effects of rapid thermal annealing (RTA) temperature on the structural and electrical properties of 10 nm-thick Hf_0.5Zr_0.5O₂ (HZO) thin films were investigated. Structural analyses revealed that the films remained largely amorphous at low annealing temperatures and crystallized above 600 °C, where the ferroelectric orthorhombic phase became dominant. At higher temperatures, the formation of the monoclinic phase was also observed. Electrical characterization demonstrated a strong dependence of ferroelectric behavior on annealing temperature. Films annealed near 600 °C exhibited the most stable ferroelectric domains, strongest polarization switching, and most distinct hysteretic behavior, whereas higher temperatures led to a gradual degradation of the electrical response. These results indicate that an annealing temperature around 600 °C provides the optimum condition for achieving enhanced ferroelectric performance in HZO thin films.