Characterization of gaseous phase and nanoparticles produced in ultra-short pulsed laser ablation of transition metal borides

The plasma produced by ultra-short laser ablation of ZrB2 and ReB2 has been studied by ICCD imaging and time and space resolved optical emission spectroscopy. The aim was to clarify the mechanism of deposition leading to the morphology and composition found in the deposited films. The results indicate that for all systems the film characteristics are compatible with a deposition mechanism involving a growth from nanoparticles, ejected directly from the target, whose composition can be interpreted in terms of equilibrium vaporization during the flight from the target to the substrate.

Research highlights▶ Ultrashort PLA of zirconium and rhenium diborides produces a large number of nanoparticles. ▶ The stoichiometry of the deposited films is related to the nanoparticles composition. ▶ The main mechanism of material loss for nanoparticles is vaporization during the flight to the substrate.