Oxygen background gas influence on pulsed laser deposition process of LaAlO3 and LaGaO3

We investigate pulsed laser ablation of LaAlO3 and LaGaO3 with a focus on the influence of oxygen background gas pressure on the plume expansion dynamics and deposition rate. The ablation plume is characterized by exploiting fast photography and time- and space-resolved optical emission spectroscopy. The variation of the deposition rate with the oxygen background pressure was obtained at 800 °C by reflection high-energy electron diffraction, and compared to that measured at room temperature by means of a quartz crystal microbalance. The experimental findings allow one to address the various stages of plume expansion as a function of the background oxygen pressure as well as the changes induced on the plume species kinetic energy and composition. On the base of our experimental results, the possible influence of various mechanisms, such as subplantation and oxygen vacancy formation, on the growth of oxides interfaces is addressed.