The Influence of Metallic Inter-layer on the Structural, Optical and Electrical Properties of ITO Thin Films Annealed at Different Temperatures

In this work new transparent conductive films that had a sandwich structure composed of ITO/metal/ITO multilayer films were prepared by reactive thermal evaporation technique on glass substrates without intentional substrate heating. Ag, Au and Cu thin films have been used as intermediate metal layer. The thickness of each layer in the ITO/metal/ITO films was kept constant at 50nm/10nm/40nm. The films were annealed in air at different temperatures ranging from 300 to 540°C for 1 h. The structural and optoelectrical properties of the films were compared with conventional ITO single-layer films with 100 nm thickness. XRD pattern showed that both inserting an intermediate layer and increasing annealing temperature have profound influence on the crystallinity and the electrical properties of thin films. It was found from SEM images that IMI films are composed of small nanoparticles The UV-Visible transmittance spectra were also confirmed that the annealing temperature has significant effect on the transparency of multilayered films.