Pulsed-discharge-aided laser ablation synthesis of nanoscale aluminum nitride powders

Pulsed nitrogen (N₂) discharges were shown to efficiently generate atomic nitrogen that promoted the synthesis of high-purity aluminum nitride powders formed by pulsed-laser ablation of aluminum targets. The interaction between the nitrogen discharge plasma and the ablated aluminum plume depended on the synchronisation of the two pulsed events for maximum overlap of the transient reactants. By monitoring the optical emissions of the reactive N⁺ species and analysing the synthesised powder with X-ray photoelectron spectroscopy, it was found that when laser ablation occurred at about 3 μs after the pulsed discharge, the N⁺ emission from the overlapping plasma was the most intense and the purity of the aluminum nitride synthesized was the highest.