Optical properties of undoped and Al-doped ZnO thin films deposited via spray pyrolysis technique
We report the optical properties of undoped and aluminum (Al)-doped zinc oxide (ZnO) thin films to realize their potential scintillator applications. Hexagonal wurtzite ZnO thin films with varying Al-doping concentrations were successfully fabricated using spray pyrolysis technique on seeded glass substrates. Both undoped and Al-doped thin films exhibit up to 75% transmittances in the visible region and 20 to 30 ps emissions around 381 nm. Increasing the Al-doping, however, results in a slight reduction of the films' visible transmittances by 3 to 15% and an increase of the green emissions by one order of magnitude. At the moment, these observed effects of Al-doping on the optical properties of ZnO thin films are attributed to the presence of Al-related impurities. Nevertheless, our results provide vital insights on the suitability of Al-doped ZnO films as fast ultraviolet (UV) scintillators for molecular dynamics (MD) investigations.