Effect of Vanadium Doping on Ferroelectric Hafnia

Hafnium oxide (HfO₂) is a well-known ferroelectric material whose properties can be tuned through doping and defect engineering. Vanadium doping has recently drawn interest due to reports of improved endurance, long retention, and negative capacitance behavior. While experimental findings highlight its strong ferroelectric performance, key questions remain about the atomic-scale mechanisms related to vanadium doping, including the roles of valence states, its interaction with oxygen vacancies, and its effect on switching kinetics. Here, first-principles calculations are employed to systematically investigate the energetic, electronic, and structural properties of V-doped HfO₂. Our results reveal that the incorporation of vanadium significantly enhances phase stabilization and strongly alters the behavior of oxygen vacancies. These findings provide atomistic insight into the effects of vanadium on ferroelectricity and phase stability, informing the design of high-performance hafnia-based ferroelectrics for next-generation memory devices.