Photoresponse characteristics of aluminium doped zinc oxide nanostructure thin films / Mohd Nasron Masri

The wide band gap semiconductor of zinc oxide (ZnO) has emerged as a potential material for the fabrication of a range of devices including opto-electronic devices such as light - emitting diodes (LEDs), laser diodes (LDs) and detectors. The goal of this research to achieve the photoresponse characteristic of Al doped ZnO thin films. The thin films of ZnO was doping with different Al concentration using sol-gel method. Dipcoating technique was applied to deposit the glass substrate dip into the ZnO solution. The thin films were dip five times and the preheating temperature at 200°C. All the dipping parameter was fixed and the molar concentration of Al were varies at 1at.%, 3at.%, 5at.%, 7at.% and 9at.%. The thin films were annealed for 1 hour before characterization process. The influence of doping concentration of aluminum on the surface morphologies was characterized by Scanning Electron Microscopy (SEM). The electrical properties of thin films were characterized using 2-probe Current-Voltage (I-V) measurement system (Advantest R6243). The optical properties were studied using UVVis-NIR spectrometer. The as prepared ZnO nanostructure thin films layers have a grain structure and show a comparably low photocurrent magnitude under dark to illumination. The results show that higher conductivity found under illumination. Al doping concentration proportional increased with electrical conductivity.