Fabrication of ultra-violet photodetector with enhanced optoelectronic parameters using low-cost F-doped ZnO nanostructures

Abstract In this work, photodetectors based on undoped (ZO) and fluorine-doped ZnO (FZO) nanostructured films were fabricated on silicon substrates using the hydrothermal method. The morphological, compositional, structural changes, and UV detection properties were investigated. FESEM and TEM revealed well-arranged vertically aligned nanorod (NRs) growth on the substrate. XRD analysis revealed a hexagonal structure of the ZnO phase with a strong (002) predominance of the peak plane. XPS and EDX analyses have shown the presence of fluorine doping. F-doping increases the band gap value of the growing material from 3.26 to 3.28 eV. The photocurrent value has improved significantly from 7.37 μA to 624.37 μA at 4 V. The response speed, responsivity, detectivity, and external quantum efficiency of ZO and FZO were also investigated and comparisons were made. We found that the FZO sample demonstrates enhanced photodetection parameter values at low bias voltage, showing great potential in optoelectronic applications.