Method and system for producing a selected pattern or array of at least one
of a single wall nanotube and/or a multi-wall nanotube containing
primarily carbon. A substrate is coated with a first layer (optional) of a
first selected metal (e.g., Al and/or Ir) and with a second layer of a
catalyst (e.g., Fe, Co, Ni and/or Mo), having selected first and second
layer thicknesses provided by ion sputtering, arc discharge, laser
ablation, evaporation or CVD. The first layer and/or the second layer may
be formed in a desired non-uniform pattern, using a mask with suitable
aperture(s), to promote growth of carbon nanotubes in a corresponding
pattern. A selected heated feed gas (primarily CH.sub.4 or C.sub.2 H.sub.n
with n=2 and/or 4) is passed over the coated substrate and forms primarily
single wall nanotubes or multiple wall nanotubes, depending upon the
selected feed gas and its temperature. Nanofibers, as well as single wall
and multi-wall nanotubes, are produced using plasma-aided growth from the
second (catalyst) layer. An overcoating of a selected metal or alloy can
be deposited, over the second layer, to provide a coating for the carbon
nanotubes grown in this manner.
