Characterization of Cl-doped n-type Cu₂O prepared by electrodeposition

N-type doping of cuprous oxide (Cu₂O) films by chlorine (Cl) during electrodeposition was reported by the authors recently. A more detailed study on the effects of doping conditions on electrical properties of Cl-doped Cu₂O is presented in this paper. The resistivity of Cl-doped Cu ₂O is affected by doping conditions, including Cu and Cl concentrations, different Cu and Cl precursors, complexing agent concentration, solution pH, and deposition temperature. It is believed that these conditions control the amount of Cl incorporated into the Cu₂O films, thus the doping level. The lowest resistivity obtained so far is 7 Ω-cm, suitable for solar cell applications. Photocurrent-potential measurements verify the n-type conductivity of Cl-doped Cu₂O. Scanning electron microscopy indicates a small grain size of around 100 nm in Cl-doped Cu₂O. X-ray diffraction confirms Cu₂O as the only detectable phase in the film.