Continuum light emission from sputtered species of graphite during ion beam irradiation
Accelerator Laboratory, NPD, PINSTECH, P.O. Nilore, Islamabad, Pakistan
Revised: 11 February 2000
Published online: 15 October 2000
Light emission during sputtering of graphite targets with 1-10 keV Ne+, Kr+ and Xe+ beams has been investigated in the 180-600 nm wavelength range. Beside the characteristic lines of sputtered C1 and C, a continuum superimposed with a number of broad structures was observed in the 250-520 nm range, and having a maximum at 386 nm. Mass analysis of the sputtered flux confirmed the presence of negative carbon clusters C , C being the dominant one. Ion beam parameters i.e. ion mass, energy, current density and ion dose were varied to identify the origin of the continuum emission. On the basis of the experimental results, it is suggested that the continuum is predominantly due to the overlapping of various band systems of sputtered C2 with a small contribution from the heavier sputtered carbon clusters Cm (m> 2).
PACS: 34.50.Dy – Interactions of atoms, molecules, and their ions with surfaces; photon and electron emission; neutralization of ions / 36.40.-c – Atomic and molecular clusters / 79.20.-m – Impact phenomena (including electron spectra and sputtering)
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2000