In-situ plasma monitoring by optical emission spectroscopy during pulsed laser deposition of doped Lu2O3

The control and arguably the tailoring aspect of technologies like pulsed laser deposition (PLD) rises from understanding the chemistry hidden by the laser generated plasma. With the continuous transition towards thin films with complex structures and geometries, the comprehension of the fundamental processes during the film deposition becomes critical. During the PLD of Mo and Eu-doped Lu2O3, optical emission spectroscopy was implemented for in-situ plasma monitoring. The spatial distribution of individual elements revealed the structuring of a stoichiometric plasma while the formation of LuO molecule within the plasma plume is seen as being induced by the addition of a minimum 1 Pa of O2. The energy of the ejected particles was controlled through doping and O2 pressure. The effect of O2 pressure over the plasma energy revealed a transition from an atomic dominated region towards a molecular dominated one. The properties of the resulted films were analyzed by XRD, AFM, and photoluminescence techniques and show a strong correlation between the dynamical regime of the plasma and their structural properties.