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Catalyzed chemical vapor deposition is the most practical method
for development of carbon nanotube devices. It is both scalable
and compatible with integrated circuit and MEMS manufacturing processes.
CVD allows high specificity of single wall or multi wall nanotubes
through appropriate selection of process gasses. Carbon feedstock
comes from the decomposition of a feed gas such as Methane or Ethylene.
 The
high stability of the feed gas prevents it from decomposing in the
elevated temperatures of the furnace. Typically, decomposition will
take place at 800 to 1000 degrees Celsius for SWNT, and 550 to 750
degrees Celsius for MWNT. Decomposition of the feed gas occurs only
at the catalyst sites, reducing amorphous carbon generated in the
process. Decomposed carbon molecules then assemble into nanotubes
at the catalyst nano-particle sites.
Catalyst nano-particles can be patterned
on a substrate lithographically to seed nanotube growth at intended
locations. The growth of nanotubes can be caused to originate at
a site of electrical connection or of mechanical significance.
CONTROL OVER NANOTUBE SYNTHESIS
Carbon nanotubes have been demonstrated as enabling components
of various electronic and chemical-mechanical devices functional
on the molecular scale. Among these devices are chemical force sensors,
gas detectors, field emission displays, molecular wires, diodes,
FEDs, and single-electron transistors.
To develop these devices into manufacturable
products and to gain control of device assembly on the molecular
level a practical technique for in situ nanotube growth is needed.
Relatively low temperatures of the process and the ability to pattern
the catalyst material directly on device substrates make catalytic
CVD the method of choice for nanotube device development. The EasyTube™
was designed to put the power in the hands of our customers to create
and innovate with this exciting new medium.
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Catalyzed
CVD Carbon Nanotube Growt