This work experimentally investigated the wake-up behaviors of hafnium oxide-based ferroelectric capacitors by manipulating the interval time between each characterization cycle. Both Positive-Up–Negative-Down (PUND) and Negative-Down–Positive-Up (NDPU) waveforms were used as the stress and measurement waveforms in the experiments. It was found that the imprint occurs as the total interval time increases to a several-seconds level. However, this only affects the remnant polarization (P_R) of ferroelectric capacitors when stressed by NDPU waveforms, since the voltage amplitude saturates under the PUND stress conditions and does not influence the P_R. The wake-up behavior has been proved to be caused by the defects redistribution during electrical cycling. Notably, when using PUND waveforms, the change in the interval time can result in different increase rates of P_R, indicating the possibility of recovery during the intervals. This recovery leads to a slower wake-up when cycling with a longer interval time. Moreover, it is observed that this P_R recovery could reach saturation after several seconds of the interval time. This comprehensive investigation of wake-up and imprint behaviors can provide new insights to evaluate and enhance the reliability of ferroelectric memories.

The nonvolatile application of La-doped ZrO₂ (ZLO) antiferroelectric capacitors is demonstrated in this study, accompanied by systematic investigation of device reliability. A built-in electric field was successfully established through engineered work function modulation. The fabricated nonvolatile (NV) ZLO capacitor exhibits not only avoidance of wake-up and fatigue phenomena typically observed in ferroelectric systems but also demonstration of ultralow coercive voltage (2Vc = 1.2 V) and exceptional endurance exceeding 10¹² cycles. The inherent unique polarization reversal mechanism in NV ZLO device was identified as the origin of a unidirectional imprint effect. Accelerated testing at 85 °C for 10⁴ s yielded conclusive evidence of retention characteristic stability. This investigation provides a novel perspective for the engineering utilization of antiferroelectric materials and facilitates their potential incorporation into advanced integrated circuit architectures.

The conventional static imprint effect in Hf_xZr_1−xO₂ (HZO) ferroelectric (FE) devices, which degrades data retention, is generally characterized by a shift in the hysteresis loop along the electric field axis. Unlike the static imprint effect, the dynamic imprint effect emerges under dynamic electric fields or actual operating conditions, making the FE film exceptionally sensitive to switching pulse parameters and domain history. In HZO anti-ferroelectric (AFE) devices, this dynamic imprint effect alters the coercive field distribution associated with domain switching and poses a significant challenge to long-term stable device operation. This study systematically investigates the dynamic imprint effect and its recovery process using a comprehensive integration of first-order reversal curve (FORC) analysis, transient current-voltage (I-V), and polarization-voltage (P-V) characterization. By analyzing localized imprint behavior under sub-cycling conditions, mechanisms and recovery pathways of imprint in AFE devices are proposed. Finally, possible physics-based mechanisms describing imprint behaviors and recovery behaviors are discussed, providing insights for optimizing AFE memory technology performance and reliability.