Preparation and photoelectric properties of F-doped cuprous oxide thin films

Abstract F-doped Cu2O films were deposited on Cu sheet substrates by hydrothermal method with different doping concentrations of F−. The structure, morphology, composition and forbidden bandwidth of the samples were characterized by XRD, SEM, EDS, UV–Vis and XPS. The photoelectric properties, capacitance-voltage and AC impedance characteristics were also studied. The undoped and F-doped Cu2O thin films are all p-type semiconductors. When the doping concentration of F− is 0.002 mol/L, the preferential growth surfaces are (110), (111) and (200), and the crystallinity of (111) plane is optimal. After doping, the grain size of F-doped Cu2O is relatively uniform. The mass percentage of F element is 0.34% and the forbidden bandwidth reduces from 1.96 eV to 1.91 eV. Photovoltage and photocurrent density increase to 0.4457 V and 2.79 mA/cm2, respectively. And the carrier concentration increases from 4.55 × 1018 to 2.58 × 1022 cm−3. The resistance value under light reduces from 183.4 Ω to 55.8 Ω.