The name is absent

3. At the exact time the set point is reached, begin flow of "bubbler gas" (Qb)
through water bubbler.

4. After bubbling for the desired "bubbling time" (⅛), initiate the flow of the
"hydrocarbon gas” (Qh).

5. After the desired "synthesis time” (t_s) has elapsed, bypass the bubbler through
the three-way valve and turn off all but the Qb during cool down.

Step 1 of the growth procedure was necessary in order to be sure that the
substrates were all entered into the furnace at the same temperature and that they
would be exposed to the growth atmosphere during heat-up for the same amount of
time from run-to-run. If a free-standing mat of CNTs is desired, the Qb can be left
flowing through the bubbler after the carbon source is turned off and before cool
down, where the added vapor can act as a weak oxidant and cause the CNTs to
release from the substrate [22].

Aligned CNTs

Iron (1.5 nm)

Aluminum (10 nm)

Silicon Wafer

Figure 2.1 - Schematic of pre-deposited CVD growth substrate (not to scale).

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