Iron-doped indium saving indium-tin oxide (ITO) thin films sputtered on preheated substrates

Iron-doped indium tin oxide (ITO) thin films with reduced to 50 mass% indium oxide content were prepared by co-sputtering of ITO and Fe2O3 targets in mixed argon-oxygen atmosphere onto glass substrates preheated at 523 K. The influence of working gas flow rate and heat treatment temperature on the electrical, optical, structural, and morphological properties of the films was characterized by means of four point probe, Ultraviolet-Visible (UV-Vis) spectroscopy, X-ray diffraction and atomic force microscopy methods. Doping of ITO films by iron using Fe2O3 target resulted in increasing transmittance of films. Iron-doping hindered the crystallization of the ITO thin films. It has been found from the electrical measurements that films sputtered under optimum conditions showed values of volume resistivity 992 mu Omega cm. It has been shown that iron doped indium tin oxide films have smooth surface in contrast to conventional ITO.