Antireflective surface of nanostructures fabricated by CF 4 plasma etching

In this research, the nanostructures surface were fabricated by the CF 4 plasma etching process on the SiO 2 -based substrates for antireflection applications. The nickel films were firstly deposited on the substrates by the sputtering system. The prepared Ni layers were then annealed at 500°C for 1 minute in order to promote dewetting process to be used as metal masks. During the etching process, CF 4 etching condition was performed for 15-60 min to create the SiO 2 nanopillars. After the etching process, the samples were immersed in nitric acid for 5 min to remove the nickel masks. The SiO 2 nanopillars without Ni were investigated for physical morphologies and optical properties by the field-emission scanning electron microscopy (FESEM) and  UV-Vis-NIR spectroscopy respectively. The results showed that the etching conditions greatly affected the sizes and shapes of the nanostructures, as well as improved the antireflection properties of the SiO 2 based materials.