Grow single-walled carbon nanotubes cross-bar in one batch

Large area, well-aligned single-walled carbon nanotubes (SWNTs) with node density up to 10⁷/cm² are prepared by a convenient one-step process, which is based on the two growth modes of carbon nanotubes: gas flow-directed growth mode and lattice-orientated growth mode. Carbon nanotubes cross-bar is realized by chemical vapor deposition approach where the direction of gas flow and the direction of lattice of the substrate (quartz) are perpendicular. Catalyst-pattern technique is applied to produce shipshape cross-bar structure, and optimum condition (especially growth temperature) for the process is carefully studied. Interaction between catalyst and substrate is identified as a critical factor for fabrication of SWNTs cross-bar for such interaction affects the length of lattice-orientated carbon nanotubes as well as the density of gas flow-directed carbon nanotubes. This growth phenomenon offers a capability to control the formation of the cross-bar structure.