Fabrication and characterization of ultraviolet photosensors from ZnO nanowires prepared using chemical bath deposition method

Abstract

Highly crystalline zinc oxide (ZnO) nanowires (NWs) were synthesized through chemical bath deposition (CBD) method by using a simple seeding technique. The process includes dispersion of commercially available ZnO nanoparticles through spraying on a desired substrate prior to the CBD growth. A typical growth period of 16 h produced ZnO NW assemblies with an average diameter of ∼45 nm and lengths of 1–1.3 μm, with an optical band gap of ∼3.61 eV. The as-prepared ZnO NWs were photoactive under ultra violet (UV) illumination. Photodetector devices fabricated using these NW assemblies demonstrated a high photoresponse factor of ∼40 and 120 at room temperature under moderate UV illumination power of ∼250 μW/cm2. These findings indicate the possibility of using ZnO NWs, grown using the simple method discussed in this paper, for various opto-electronic applications.