n-Type Conductivity of Cu2O Thin Film Prepared in Basic Aqueous Solution Under Hydrothermal Conditions


We report for the first time in situ hydrothermal synthesis of n-type Cu2O thin film using strong alkaline solution. The use of copper foil as substrate and precursor material, low synthesis temperature and short reaction time represent the arguments of a new, simple, inexpensive and high field synthesis method for the preparation of n-type Cu2O thin film. The donor concentration of n-type Cu2O thin film obtained at 2 h of reaction time has increased two orders of magnitude than previous reported values. We have demonstrated n-type conduction in Cu2O thin film prepared in strong alkaline solution, in the contradiction with the previous works. Based on experimental results, the synthesis mechanism and the origin of n-type photo-responsive behavior of Cu2O thin film were discussed. We have proposed that the unexpected n-type character could be explained by H doping of Cu2O thin film in during of the hydrothermal synthesis that caused the p-to-n conductivity-type conversion. Also, this work raises new questions about the origin of n-type conduction in Cu2O thin film, the influence of the synthesis method on the nature of the intrinsic defects and the electrical conduction behavior.

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This work was supported by a grant of the Romanian National Authority for Scientific Research and Innovation, CNCS/CCCDI—UEFISCDI, Project No. PN-III-P2-2.1-PED-2016-0526, within PNCDI III.

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Correspondence to Marinela Miclau.

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Ursu, D., Miclau, N. & Miclau, M. n-Type Conductivity of Cu2O Thin Film Prepared in Basic Aqueous Solution Under Hydrothermal Conditions. Electron. Mater. Lett. 14, 405–412 (2018). https://doi.org/10.1007/s13391-018-0047-9

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  • n-Type semiconductor
  • Hydrothermal synthesis
  • Cuprous oxide
  • Intrinsic n-type defects