Fabrication of vertically aligned carbon nanowalls using capacitively coupled plasma-enhanced chemical vapor deposition assisted by hydrogen radical injection

Abstract

Two-dimensional carbon nanostructures (carbon nanowalls) were fabricated using capacitively coupled radio-frequency plasma-enhanced chemical vapor deposition assisted by H radical injection. Carbon nanowalls were grown on Si, ${\mathrm{SiO}}_2,$ and sapphire substrates without catalyst, and independent of substrate materials. Correlation between carbon nanowall growth and fabrication conditions, such as carbon source gases was investigated. In the case using ${\mathrm{C}}_2{\mathrm{F}}_6/{\mathrm{H}}_2$ system, aligned carbon nanowalls were grown vertically on the substrate, while carbon nanowalls grown using ${\mathrm{CH}}_4/{\mathrm{H}}_2$ system were waved and thin (<10 nm). In the case of the deposition without H radical injection, on the other hand, carbon nanowalls were not fabricated.