Laser ablated Sr_2FeMoO_6 plasma studied by optical emission spectroscopy

摘要

The pulsed laser ablation and deposition of Sr_2FeMoO_6 films having good magnetic performances is strongly affected by the adopted deposition parameters, which require precise choices. Among them, the laser energy density seems to be the basic factor governing the achievement of the correct material phase during film growth. Optical emission spectroscopy of the plasma plume, produced by the laser interaction with stoichiometric targets, in different ablation and ambient conditions, can outline the plasma dynamics and consequently sustain hypothesis about the film formation mechanism. In order to follow the plasma dynamics during Nd:Yag laser (λ=532 nm) ablation of Sr_2FeMoO_6 targets, time- and space-resolved optical emission spectroscopy measurements in the range 350 -500 nm have been performed. The integral intensities of spectral lines were measured as a function of distance from the target surface and laser power density in the presence of O_2 partial pressure. The intensity ratio of ionic and atomic Strontium emission spectral line and their time-of-flights were measured as a function of laser energy density. On the basis of the obtained results it is shown how different plasma species kinetics can play a key role in determining the magnetic film properties.