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tube where it will be picked up by the carrier gas and carried through the reaction
zone. The entire vapor-phase CVD growth setup is pictured in Figure 2.8.
With the furnace assembled, again comes the task Ofdeveloping a successful
growth method. The parameters used for the successful synthesis of A-CNTs via the
xylene/ferrocene process [43] were used as a starting point for this setup, and the
procedure used for the synthesis of these CNTs is as follows:
1. Begin flowing the carrier gas (Qc) and heat furnace up to the introduction
temperature (Ti).
2. When stable, place substrate into the center of the growth zone and begin
heating to the desired set point temperature for the synthesis (Ts).
3. At the exact time the set point is reached, begin flow of evaporator gas (Qe) and
initiate the flow of the catalyst∕carbon source liquid mixture (Q∕) which has a
specific ratio of catalyst-to-carbon-source (C:CS).
4. After the desired synthesis time (ts) has elapsed, turn off all flow but the Qe
during cool down.