Structural and optical band gap modification of Zn2SnO4 thin films after irradiation with swift heavy ions for transparent electrode applications

Abstract

The structural changes and their effect on optical properties have been studied in Zn2SnO4 thin films irradiated by Ag9+ ions. The irradiation of thin films transforms the mixed crystal structures in to a single diffraction plane. In the XRD, the single peak is the result of atomic jump within the material due to the change in activation energy after irradiation. The XRD and SEM confirmed the modifications of lattice parameters and grains in accordance with the basic requirement of material to be used as transparent conducting oxides. In optical studies, the absorption spectra and Tauc plot confirm the neutralization of free electrons in conduction band minimum which results in an increase in the optical band gap for better transmission in visible range. The results indicate that the swift heavy ions passed from polycrystalline material synergistically with inelastic electronic energy loss to promote the formation of Zn2SnO4 oriented in a single direction and lead to rapid phase transformation.