The Geometry Variation of As‐Grown Carbon Coils with Ni Layer Thickness and Hydrogen Plasma Pretreatment

Abstract

Carbon coils could be synthesized using C2H2/H2 as source gases and SF6 as an incorporated additive gas under thermal chemical vapor deposition system. Ni layer on SiO2 substrate was used as a catalyst for the formation of carbon coils. Ni powder was evaporated to form Ni layer on the substrate. The characteristics (formation densities, morphologies, and geometries) of as‐grown carbon coils on the substrate were investigated as a function of the evaporation time for Ni catalyst layer formation. By hydrogen plasma pretreatment prior to carbon coils synthesis reaction, the dominant formation of the nanosized wave‐like geometry of carbon coils could be achieved. The characteristics of as‐grown carbon coils with or without hydrogen plasma pretreatment process were investigated. The cause for the control of the carbon coils geometries from the microsized type to the nanosized wave‐like one by H2 plasma pretreatment was discussed in association with the stress of Ni catalyst layer on the substrate.