Synthesis and characterization of Cu-Doped ZnO nanostructures for UV sensing application

In this work, Fabrication, and characterization of Cu-doped ZnO thin films deposited on porous silicon (PSi) substrates have been reported using electrochemical deposition (ECD) technique. The influence of Cu-doping concentrations on morphology, structure, and electrical characteristics of zinc oxide (ZnO) thin films were presented. X-ray diffraction analysis (XRD) has been used to characterize the lattice constants, average size, in-plane (along a-axis) and out of plane (along c-axis) strains for the Cu-ZnO crystals. The effects of Cu-doping concentration on crystal parameters were also investigated from the XRD analysis. The samples were used for UV-sensing applications. In addition, Cu-doped ZnO and pure ZnO metal-semiconductor-metal photodetector, with Cu as electrode contacts were successfully produced for ultraviolet (UV) detection. The I-V (current-voltage) characteristics were used to study the sensing enhancement. Finally, the UV photodetector based on Cu-doped ZnO films was successfully fabricated and shows a five times enhancement in the sensitivity to UV light compared to that of pure ZnO photodetector.