Enhanced ferroelectricity and endurance in Hf0.5Zr0.5O2/ZrO2 multilayer thin films prepared by chemical solution deposition

In the present work, Hf 0.5 Zr 0.5 O 2 (HZO) ferroelectric thin films were deposited on Pt/Ti/SiO 2 /Si substrates by chemical solution deposition (CSD), and the effects of annealing temperature and ZrO 2 interlayer insertion on their phase structure and ferroelectric properties were systematically investigated. The results show that a higher annealing temperature promotes the formation of the ferroelectric orthorhombic (o) phase, with the film annealed at 800 °C reaching a remanent polarization (P r ) of 26.51 μC/cm 2 . Building on this, a ZrO 2 interlayer strategy was adopted to optimize the ferroelectric performance further. Rietveld refinement and HAADF-STEM analyses reveal that the multilayer architecture, formed by alternately inserted ZrO 2 interlayers, provides additional nucleation sites and introduces interfacial stress, thereby inducing the preferential crystallization of the o phase. The multilayer film reaches a remanent polarization as high as 63.05 μC/cm 2 , outperforming previously reported CSD-prepared HfO 2 -based ferroelectric films, and shows no obvious fatigue after 10 7 cycles. This work offers a low-cost and reliable route to high-performance HfO 2 -based ferroelectric films and holds promise for nonvolatile memory applications.