The Enhanced Polarization Switching Speed and Endurance in Hf₀.₅Zr₀.₅O₂ Ferroelectric Thin Film by Modulating Oxygen Dose in Ferroelectric Layers

In this letter, the ferroelectric capacitors featuring Hf 0.5 Zr 0.5 O 2 films with different oxygen dose have been constructed. It is found that the sample grown at oxygen-deficient condition exhibits a smaller remanent polarization (P r ), a larger dielectric constant (ε r ), a faster switching and better cycle reliability (over 10 8 @ 4 MV/cm). The connection between its better reliability and polarization switching speed with its dielectric and ferroelectric properties is established with the switching-induced charge-injection model. The larger interfacial depolarization field ( E dep ) impedes the domain switching at the early nucleation process and wears out the metal/ferroelectric interface, leading to the endurance degradation. Our work reveals that the oxygen-deficient sample with a smaller P r and a large ε r shows a smaller E dep near the interface, tend to switch faster, thus also benefits the reliability. It provides better understanding of process modulating domain switch kinetics and reliability in HfO 2 based ferroelectric devices from both theoretical and experiment perspective.