Formation of catalyst particles for the CNT growth from thin films: Experiment and simulation

Abstract

The formation of Ni nanoparticles for the growth of carbon nanotubes on a TiNbarrier layer obtained by atomic layer deposition was studied. The interaction of the catalyst with the barrier layer is revealed. It consists of diffusion of Ni into TiN with activation energy of 0.75 eV.Assuming the melting of a nanosized Ni film, we simulated the formation of catalyst particles in terms of wetting transition theory. Comparison of simulation results and experimental data on catalyst particle formation allowed us to estimate effective interaction potential of Ni film and barrier layer. A change of the interaction potential due to variation of the film or barrier layer properties (e.g., material, structure, etc.) is responsible for change of the dynamics of catalyst particle formation including dynamics of their average size, number density and the shape of the size distribution function.