Nitride-molecule synthesis in plasma produced by reactive laser ablation assisted by RF discharge for thin-film deposition

In this work a radio frequency discharge is associated to a pulsed KrF excimer laser deposition set-up; experiments are performed in N2or NH3ambient gas for reactive laser ablation yielding nitride thin films. The laser ablation of the target leads to vapour plume plasma expanding into the ambient gas and resulting in nitride-molecule formation. It can be supposed that the nitride-deposition rate depends on the molecular-production rate. Nitride molecules are investigated by plasma emission spectroscopy and imaging device for different experimental conditions gas nature and pressure in 0.01–1 Torr range.. To enhance the gas reactivity, a RF discharge is coupled to the PLD set-up. A comparison is done between molecular spectra intensities obtained from the different experimental conditions. The study is applied to C N synthesis from C x y graphite in ambient gas containing nitrogen species. The nitrogen concentration contained in the thin films produced is determined by nuclear analysis to establish the best experimental conditions to obtain the expected 3,4 stoichiometry nitride. q1998 Elsevier Science B.V.