Direct synthesis of single-walled carbon nanotubes selectively suspended on tips of vertically aligned silicon nanostructures fabricated by hydrogen plasma etching

摘要

Here we present a method to synthesize single-walled carbon nanotubes (SWNTs) selectively suspended on tips of silicon-based nanostructure (Si-ns) templates. The Si-ns templates vertically aligned to the substrates are fabricated via an anisotropic etch process using reactive hydrogen plasmas, in which the etch-resistive nanomasks are the nanosized particles formed by thermal annealing of multi-layered catalytic thin films. After plasma etching, the nanosized self-masks remaining at the tips of the Si-ns directly serve as the catalysts for SWNT growth by thermal chemical vapour deposition. Consequently, the synthesized SWNTs are selectively suspended on the tips of the Si-ns, as revealed by characterizations using scanning electron microscopy and resonance Raman spectroscopy. This methodology provides a simple and straightforward approach to assemble two different nanomaterials, i.e., Si-ns and suspended SWNTs, together as a building block for constructing nanodevices for possible applications.