Pulsed laser ablation of MoSi2: gas phase analysis

The gaseous phase produced by laser ablation of a molybdenum silicide
target has been analysed by time-of-flight mass spectrometry, emission
spectroscopy and fast imaging performed by an ICCD camera, in order to
obtain informations about the mechanisms involved in the laser deposition
of MoSi2 thin films. During laser ablation, the emission spectra indicate
a target temperature of about 7200 K, while the mass spectra evidence the
presence of clusters corresponding to the formula (MoSi2)(n) with n up to
2. The results suggest that the possibility to deposit stoichiometric thin
films is related to the composition of the plasma and, in particular to
the presence of cluster with the right silicon molybdenum ratio. The
presence of a large amount of clusters could be due to reactions in the
plasma.