Effect of Au thin film thickness and surface nanoparticles morphologies on the optical band gap and photoluminescence of ZnO thin films deposited by pulsed electron deposition technique

In this work, the effect of Au thin films on band gap and photoluminescence of ZnO thin films in ZnO/Au/Si structure has been investigated. The Au nanoparticle thin films firstly were deposited via sputtering method onto silicon (Si) substrate, and then the ZnO thin films were deposited on the Au-covered Si substrates (Au/Si) by pulsed electron deposition technique. This research mainly focused on the influence of the thickness of the Au thin films being on Silicon substrate and its surface on absorption and fluorescence properties of ZnO thin films. The results showed that with increasing the Au thin films thickness, the optical band gap of ZnO thin films is gradually increased. In particular, the changes in thickness and surface morphology of the Au thin films have a strong effect on excitonic emission band in the ZnO thin film.