Characterization of rear- and front-side laser ablation plasmas for thin-film deposition

Thin-film deposition by rear-side laser ablation has been reported as a new configuration for transparent materials. In order to study the features of this configuration, characterization of the rear-side and front-side plasmas was performed. Experiments were carried out in a low vacuum (50 Torr), using SiO2 targets and a Nd:YAG laser as the energy source. The shock wave associated with rear- and front-side ablation plumes were recorded by shadowgraphy and the corresponding velocities were determined in each case. We found a spherical wave front in both cases. Optical emission spectroscopy (OES) was carried out in order to identify the excited species present in each plasma.