New Insight into the Gas Phase Reaction Dynamics in Pulsed Laser Deposition of Multi-Elemental Oxides

The gas-phase reaction dynamics and kinetics in a laser induced plasma are very much dependent on the interactions of the evaporated target material and the background gas. For metal (M) and metal-oxygen (MO) species ablated in an Ar and O-2 background, the expansion dynamics in O-2 are similar to the expansion dynamics in Ar for M+ ions with an MO+ dissociation energy smaller than O-2. This is different for metal ions with an MO+ dissociation energy larger than for O-2. This study shows that the plume expansion in O-2 differentiates itself from the expansion in Ar due to the formation of MO+ species. It also shows that at a high oxygen background pressure, the preferred kinetic energy range to form MO species as a result of chemical reactions in an expanding plasma, is up to 5 eV.

Automated summary

The gas-phase reaction dynamics and kinetics play a crucial role in laser induced plasma. This study reveals that the expansion dynamics in O-2 differ from those in Ar due to the formation of MO+ species. Furthermore, a preferred kinetic energy range of up to 5 eV is observed for chemical reactions leading to the formation of MO species in an expanding plasma under high oxygen background pressure.