Laser-Ablated Plasma Dynamics Study For Sm1-xNdxNiO3 Thin Films Deposition

The expansion dynamics of Sm1-xNdxNiO3 excimer laser ablation plume in background oxygen atmosphere has been investigated using a fast ICCD imaging. The laser fluence was fixed at 2 J·cm-2 and the surrounding ambient gas pressure was varied from vacuum to 50 mbars. The imaging data is used to create position--time plots of the luminous front at several background oxygen pressures. The plume behaviour is found influenced by the gas pressure. In earlier time, the expansion is almost linear independently of the background gas pressure used, and then as time evolves, the plume expansion is well characterized by a spherical shock wave model and at later times, the plume is decelerated and comes to rest, so the drag force model is a good approximation to this regime of expansion. Plume splitting into fast and slow components was another feature observed at some distances depending on the oxygen background pressure. The optimal target-substrate distance for thin film deposition has been estimated.