Plasma diagnostics in pulsed laser deposition of GaLaS chalcogenides

[Display omitted] ► First study on the plasma dynamics for laser ablation of chalcogenides. ► Axial velocities, excitation temperatures and electron densities derived from space- and time-resolved optical emission spectroscopy. ► Opens the way for a systematic study of plasma dynamics in view of chalcogenides PLD process optimization. The aim of this work is to characterize the ejection plume obtained by laser ablation of GaLaS (GLS) samples in order to better understand the ablation phenomena for optimizing the pulsed laser deposition of chalcogenide thin films. The dynamics of the plasma between target and substrate was investigated through time- and space-resolved optical emission spectroscopy. High-resolution optical spectra have been recorded in the UV–VIS range using a 500-mm focal length monochromator and a fast gate ICCD camera. From the space–time evolution of the optical signals, the velocities of various species (including neutrals and ions) have been derived. Using the relative intensity method, the space- and time-evolution of the excitation temperature and electronic density have been determined. A complex behavior of the laser ablation plasma has been revealed.