Antiferroelectric PUND measurements on ZrO2
Résumé
This work introduces the AFE-PUND measurement method, an original positive up negative down (PUND) protocol intended to accurately study antiferroelectric (AFE) thin-film behavior. As for its FE counterpart, the AFE-PUND method isolates switching currents from nonswitching contributions, enabling a precise extraction of saturation polarization and coercive fields from hysteresis loop curves. In this paper, AFEPUND was deployed on AFE ZrO2 films of varying thicknesses. The results reveal that saturation polarization increases with film thickness, indicating enhanced domain stability, while endurance cycles showcase the wake-up effect and its eventual fatigue-induced degradation in thicker films. Similarly, coercive fields decrease with thickness, reflecting reduced switching barriers and a sharper transition between the tetragonal and orthorhombic phases. AFE-PUND establishes itself as an extremely valuable method for advancing the understanding and optimization of AFE materials.