Passivation of oxygen vacancy defects in conductive ZnO nanoparticles via low-temperature annealing in NF3

Abstract Oxygen vacancies (V O ) often exist in wide-bandgap metal oxide semiconductors (MOSs) as deep-level defects and undermine the reliability of various optoelectronic devices based on MOSs. Conventional methods to passivate V O defects, such as high-temperature annealing or plasma treatment, can compromise device performance. This work demonstrates that passivation of V O defects in aluminum-doped ZnO (AZO) nanoparticles can be realized through low-temperature annealing (350 °C) in an NF 3 atmosphere. After the NF 3 annealing, the longitudinal optical phonon scattering mode in Raman spectroscopy, the visible light emission intensity in photoluminescence spectroscopy, and the oxygen deficiency-related peak in x-ray photoelectron spectroscopy decrease simultaneously, indicating the passivation of V O defects in AZO nanoparticles. As a result, AZO nanoparticles show higher visible light reflectance and better stability of electrical conductivity owing to the suppression of deep-level light absorption and gas molecule adsorption. This work also offers insights into the passivation mechanism of V O defects in MOSs.