Experimental and numerical study of pulsed laser ablation in vacuum and ambient gas: application to pulsed laser deposition of thin films

The application of the pulsed laser deposition technology requires a better understanding of the material evaporation mechanisms, of the gas and plasma plume formation, of its expansion and of its deposition onto the substrate. Experimental and numerical studies revealed the importance of the gas-phase collisions on the formation of a peaked angular distribution of particles described by cosp (theta) . Numerical calculations based on a Monte Carlo simulation of the desorption process were performed showing that the focusing effect of the angular distribution of particles increases with the number of collisions in the plume. This paper presents a 3D Monte Carlo simulation performed in vacuum and ambient gas in order to investigate the angular distribution of particles. Besides elastic collisions, the recombination-dissociation reactions proceed in the flow.