Pulsed laser deposition of SrTiO3/LaGaO3 and SrTiO3/LaAlO3 interfaces has been analyzed with a focus on the kinetic energy of the ablated species. LaGaO3 and LaAlO3 plasma plumes were studied by fast photography and space-resolved optical emission spectroscopy. Reflection high energy electron diffraction was performed proving a layer-by-layer growth up to 10-1 mbar oxygen pressure. The role of the energetic plasma plume on the two-dimensional growth and the presence of interfacial defects at different oxygen growth pressure has been discussed in view of the conducting properties developing at such polar/non-polar interfaces.