Abstract
This study employs first-principles calculations to investigate the defect characteristics of nitrogen impurity and oxygen vacancy coexistence within HfO2 material. We calculate the total energies of various No–Vo models at different nitrogen impurity-oxygen vacancy distances to determine the lowest energy structures. Furthermore, we compute the formation energies of oxygen vacancies in HfO2 when nitrogen impurities are present, revealing that nitrogen impurities facilitate the formation of oxygen vacancies. In addition, we conduct defect level and carrier capture energy calculations for these coexisting defects. Our defect level analysis results indicate that the No4–Vo4 coexisting defect possesses the deepest electronic defect level, suggesting its superior electron retention capability. Furthermore, our carrier capture energy calculations demonstrate that nitrogen doping enhances the carrier capture energy of HfO2 material with oxygen vacancies, thereby improving the data retention capability of the device. The findings of this study contribute valuable insights to the understanding and design of coexisting defects in experimental settings, offering potential applications in device performance enhancement.