Light emission during negative heavy ion implantation into lithium niobate and sapphire

The outward mass transport during implantation of 60 keV negative Cu, Ag and Au ions into LiNbO3 and Al2O3 was studied by using in situ time-resolved optical spectroscopy. Single crystals of LiNbO3 and Al2O3 were irradiated continuously or by pulses of ions. Spectra of ion-induced light emission at the wavelengths from 250 to 900 nm were in situ measured. The ratios of individual lines of the same atomic species (Li for LiNbO3 and Al for Al2O3) change with the dose. The change of energy distribution of sputtered atoms is explained by a competition between two mechanisms of sputtering: the sputtering induced by atomic collisions or electronic excitation. The result shows a strong relationship between irreversible structural change of implanted regions (formation of nanocomposite and damage) and energy distribution of sputtered atoms. (C) 2004 Elsevier Ltd. All rights reserved.