Capacitive Photodetector Thin-Film Cells of Cu-As₂S₃-Cu as Revealed by Dielectric Spectroscopy

The As₂S₃-Cu interface was studied by dielectric spectroscopy measurements on Cu-As₂S₃-Cu thin film heterostructure samples to assess the charge carriers' contribution to the electrical properties of such an interface. Three-dimensional printed masks ensured good reproducibility during the PLD deposition of heterostructure samples. The samples were tested for electrical conductivity and AC photoconductivity by dielectric spectroscopy measurements. DC bias voltages and light were applied to the samples. The electrical capacity of the thin film heterostructure can be modified electrically and optically. We observed long-term photoconductivity with a time dependency that was not exponential, and a quick change of the electrical capacity, indicating the potential of the heterostructure cells as photodetector candidates.