Unveiling switching kinetics in low-coercive-field wurtzite Zn0.89(Ce,Mn)0.11O ferroelectric films

Wurtzite ferroelectric films with stable ferroelectric phases exhibit significantly larger remanent polarization (Pr) compared to other materials, positing them as promising candidates for next-generation non-volatile memories. However, their intrinsically high coercive field (Ec) remains a critical challenge for low-power device operation, necessitating a comprehensive understanding of its underlying origin. In this work, the frequency- and time-dependent switching behavior in (Ce,Mn)-substituted ZnO Zn0.89(Ce,Mn)0.11O thin films is systematically investigated, and compared with (Al0.8Sc0.2)N films. The switching process follows the Kolmogorov–Avrami–Ishibashi model, consistent with the behavior observed in (Al0.8Sc0.2)N, and Ec is found to be determined by the activation field (Ea). Through pulse switching and PUND measurements across a broad temperature range, Zn0.89(Ce,Mn)0.11O shows much lower Ea and Ec than (Al0.8Sc0.2)N, while maintaining stable Pr. The origin of Ea is found to correlate with the nucleation energy barrier and threshold field independent of temperature. Furthermore, a comprehensive map of Ec as a function of time and temperature is established, offering critical insight into the operational window for ferroelectric memory devices. These findings provide a deeper understanding of the switching physics in wurtzite ferroelectrics and suggest strategies for tailoring Ec.