Nanoscale mechanisms of CNT growth and etching in plasma environment

Umedjon Khalilov (1) , Annemie Bogaerts (1) , Shahzad Hussain (2) , Eva Kovacevic (2) , Pascal Brault (2) , Chantal Boulmer-Leborgne (2) , Erik C Neyts (1)

1 Research group PLASMANT
2 GREMI - Groupe de recherches sur l'énergétique des milieux ionisés

Plasma-enhanced chemical deposition (PECVD) of carbon nanotubes has already been shown to allow chirality control to some extent. In PECVD, however, etching may occur simultaneously with the growth, and the occurrence of intermediate processes further significantly complicates the growth process. We here employ a computational approach with experimental support to study the plasma-based formation of Ni nanoclusters, Ni-catalyzed CNT growth and subsequent etching processes, in order to understand the underpinning nanoscale mechanisms. We find that hydrogen is the dominant factor in both the re-structuring of a Ni film and the subsequent appearance of Ni nanoclusters, as well as in the CNT nucleation and etching processes. The obtained results are compared with available theoretical and experimental studies and provide a deeper understanding of the occurring nanoscale mechanisms in plasma-assisted CNT nucleation and growth.

Mots clés: carbon nanotube; Ni nanocatalyst; PECVD; computer simulations; electron microscopy; H2 plasma; hydrocarbons; etching

Domaines: Plasmas; Matériaux

Umedjon Khalilov, Annemie Bogaerts, Shahzad Hussain, Eva Kovacevic, Pascal Brault, et al.. Nanoscale mechanisms of CNT growth and etching in plasma environment. Journal of Physics D: Applied Physics, 2017, 50 (18), pp.184001. ⟨10.1088/1361-6463/aa6733⟩. ⟨hal-01508183⟩