Journal of Physics D: Applied Physics, 2019,
DOI:10.1088/1361-6463/ab00d0
Abstract
Abstract Tubular magnetron was used for in-flight deposition of Cu over Ni nanoparticles (NPs) pre-synthesized in a planar magnetron-based gas aggregation cluster source. The amount of deposited copper was driven by magnetron current and magnetic field of the tubular magnetron. Structure of the resultant NPs was investigated by TEM, STEM, XRD and SAXS. Alloying of Cu and Ni was observed in all the cases, yet with the formation of copper-enriched shell in the case of higher Cu content. XRD and TEM analyses showed that plasma-NP interaction leads to the disappearance of Ni crystal lattice defects. For a certain range of the magnetron currents, spontaneous pulsing of the deposition rate of the NPs was observed which was accompanied by the changes in the NP size distribution and chemical composition. The phenomenon was attributed to the cycling trapping, growth and release of the NPs inside and from the tubular magnetron. Such cycling instabilities lead to the formation of NP deposits with high polydispersity.
