Unlocking Ferroelectricity in Hafnia: From Phase Origins to Device Integration

This review provides a systematic overview of the critical factors governing the emergence of ferroelectricity in hafnia‐based systems, covering fundamental physical mechanisms, material modification routes, device integration schemes, and state‐of‐the‐art application scenarios. The theoretical advances in crystalline phase evolution, phase transition energetics, and intrinsic ferroelectric origins of hafnia‐based systems are comprehensively elaborated from a physical perspective. Key strategies for triggering ferroelectric phase formation and optimizing functional performance in hafnia ferroelectrics are thoroughly analyzed, including elemental doping, oxygen vacancy regulation, thermal modulation, epitaxial/electrode strain engineering, as well as interfacial design via seed layers, capping layers and interlayers. In terms of device implementation, representative components such as ferroelectric capacitors, diodes, tunnel junctions and transistors are overviewed, with a further discussion on their CMOS‐compatible integration and prospective applications in nonvolatile memory and neuromorphic computing. The current progress and core challenges of hafnia‐based ferroelectrics are summarized concerning phase origin clarification, performance optimization and practical device integration. Furthermore, this review outlines potential research frontiers in such material systems, offering rational insights to guide subsequent exploration of this fast‐developing research field.