Numerical simulation of nanocluster motion through a DC magnetron nanocluster source

• The influence of the jet and the vortex in the aggregation region on the nanoparticles was investigated.
• The effect of Brownian motion on nanoparticle trajectories in a magnetron cluster source was studied.
• Magnetron cluster source with the relaxation region was firstly calculated.
• The effect of the relaxation region on the penetration of nanoparticle was studied.

The commercial computational fluid dynamics (CFD) software OpenFOAM was used to simulate the gas flow field in a direct current (DC) magnetron nanocluster source. The density of free metal atoms in the aggregation region influenced the cluster formation and the cluster intensity. In order to improve the density of nanoclusters, two factors should be considered: redeposition of the sputtered atoms within the cathode region and the loss of the nanoclusters on the chamber wall. The angles of the jet and the vortex in the aggregation region have a significant influence on the number of nanoclusters. The extent to which to the Brownian diffusion can affect the particle extraction from source is investigated. Simulations have shown that the Brownian motion perturbs the clusters from the trajectories dictated by the carrier gas and increases the rate of cluster deposition on the source internal wall.