The influence of 200 MeV Au ion irradiation on the surface properties of polycrystalline fullerene films has been investigated. The X-ray photoelectron and X-ray Auger electron spectroscopy are employed to study the ion-induced modification of the fullerene, near the surface region. The shift of C 1s core level and decrease in intensity of shake-up satellite were used to investigate the structural changes (like sp(2) to sp(3) conversion) and reduction of pi electrons, respectively, under heavy ion irradiation. Further, X-ray Auger electron spectroscopy was employed to investigate hybridization conversion qualitatively as a function of ion fluence. (C) 2008 Elsevier B.V. All rights reserved.