Irradiation of polycrystalline sputter-deposited ITO thin films on float-glass substrates was performed with high-energy MeV He+ ion beam implantation at doses in the range 2-6 x 10(+15) ions/cm(2). A significant change in both surface morphology and crystallographic structure after implantation was observed. It results in a crystallographic disorder of large crystallites with the ion dose, creation of electronic defects and a roughening of the ITO thin-films' surface. (C) 2005 Published by Elsevier B.V.