[en] This study reports the influence of magnesium incorporation into cuprous oxide (Cu2O) on its transformation into cupric oxide (CuO). Thermal treatments under oxidizing conditions are performed on undoped and magnesium-doped cuprous oxide thin films, Cu2O and Cu2O:Mg respectively, deposited by aerosol-assisted metal–organic chemical vapor deposition. The oxidation kinetics of these films shows a slower rate in the Cu2O:Mg system, since the complete oxidation into CuO occurs at a higher temperature when compared with undoped Cu2O. The increased stability of Cu2O:Mg can be explained by the inhibition of the formation of split copper vacancies, the defect most frequently associated with the CuO nucleation. Annealing treatments performed on Cu2O thin films provide new insights on the dopant influence on the mechanism to generate simple and split copper vacancies as well as the transformation of Cu2O into CuO.
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