Study of kinetics of atomic carbon during laser ablation of graphite in nitrogen by time- and space-resolved emission spectroscopy

We performed plasma optical emission studies during XeCl laser ablation of graphite in nitrogen at a laser fluence of 12 J/cm(2), this corresponding to the experimental conditions for which the growth of microcrystalline CNx film by pulsed laser deposition has been observed. In this work, we focus our attention on the temporal and spatial evolution of the C I emission line at 247.86 nm in vacuum and for different nitrogen pressures, in the range from 1 to 50 Pa. The plasma expansion in nitrogen background has been analysed in terms of drag model. Results show that in our experimental conditions gas-phase C reactions are dominant. Kinetic energies for atomic carbon of the order of tens of electronvolts have been inferred from the 4 emission spectra. (C) 2002 Elsevier Science B.V. All rights reserved.