A method for manufacturing carbon nanotubes with an integrally attached outer
graphitic
layer is disclosed. The graphitic layer improves the ability to handle and manipulate
the nanometer size nanotube device in various applications, such as a probe tip
in scanning probe microscopes and optical microscopes, or as an electron emitting
device. A thermal chemical vapor deposition reactor is the preferred reaction vessel
in which a transition metal catalyst with an inert gas, hydrogen gas and a carbon-containing
gas mixture are heated at various temperatures in a range between 500 C.
and 1000 C. with gases and temperatures being adjusted periodically during
the reaction times required to grow the nanotube core and subsequently grow the
desired outer graphitic layer.