Ion velocity, charge state and substrate dependent electronic sputtering of fullerene S. Ghosh a, * , D.K. Avasthi b , T. Som c , A. Tripathi b , S.K. Srivastava b , F. Gr€ uner d , W. Assmann d a Belonia College, Belonia, South Tripura 799155, India b Nuclear Science Centre, New Delhi 110067, India c Institute of Physics, Bhubaneswar 751005, India d Ludwig Maximilians University, M€ uenchen, Garching 85748, Germany Abstract In order to understand electronic sputtering phenomenon, a systematic study is performed by bombarding fullerene (C 60 ) thin films deposited on Si and glass substrates with Au and Ag ions of different energies. The incident ion velocity, charge state and substrate dependent electronic sputtering yield (sputtered atoms/ion) of C is measured on-line by elastic recoil detection analysis (ERDA) technique in the three different sets of studies. The salient features observed in these experiments are that the yield is quite high (10 3 atoms/ion and above), which is influenced by the above- mentioned three physical parameters. Slower ion having same electronic energy deposition (S e ) as compared to its high velocity counterpart erodes more. C 60 films deposited on more insulating substrate (electrically and thermally: glass) shows higher sputtering yield as compared to those deposited on Si substrate. However, no charge state effect was observed in the electronic sputtering yield within the detection limit of the set up. Ó 2003 Elsevier B.V. All rights reserved. Keywords: Fullerene; Swift heavy ion; Electronic sputtering; Elastic recoil detection analysis; Thermal spike 1. Introduction Interaction of swift heavy ion (SHI) with matter has become an important subject of ion–matter interaction research due its capability of depositing large energy in the material. Electronic sputtering [1–5] is one of the important effects of SHI–matter interaction. This is defined as the erosion of ma- terial through the surface due to the impact of SHI. The study of electronic sputtering is an im- portant tool to understand ion–matter interaction process. Several aspects of electronic sputtering are studied by different authors in recent times [3–5]. The effect of the structure of the material under study on electronic sputtering process is reported elaborately [4,6]. However, the effect of the phys- ical parameters related to incident ion and the substrate on which material under study is de- posited is not looked upon in detail. Incident ions having different velocities with similar electronic energy deposition (S e ) on any solid have different energy distribution [7,8]. The energy density in case of slower ion is more as compared to its higher velocity counterpart. This can give rise to a * Corresponding author. E-mail address: ghoshsantanu1@yahoo.co.in (S. Ghosh). 0168-583X/$ - see front matter Ó 2003 Elsevier B.V. All rights reserved. doi:10.1016/S0168-583X(03)01744-0 Nuclear Instruments and Methods in Physics Research B 212 (2003) 431–435 www.elsevier.com/locate/nimb