Effect of silver evolution on conductivity and transmittance of ZnO/Ag thin films

ZnO films with an embedded silver layer, one of the most promising transparent conductive materials, possess excellent conductivity and optical transmittance. The performance of ZnO films is greatly affected by the morphology of the silver layer. In this work, we studied the changes in the electrical and optical properties of ZnO/Ag multilayered films as a function of the coalescence of the silver clusters. Silver clusters aggregated into various morphologies at different layer growth stages and dominantly affected the conductivity of ZnO/Ag films as a result of different electron transport mechanisms. The optical transmittance was also enhanced by surface plasmon resonance between the incident light and the random grating of the silver clusters. The improved electrical conductivity and optical transmittance give asymmetric ZnO/Ag multilayered films the potential to be used as transparent electrodes.