Abstract
Carbon nanotubes have been investigated for their antimicrobial properties. The goal of this experiment was to better characterize the effects of gas flow rate and sample position on carbon-infiltrated carbon nanotubes (CICNTs) grown via chemical vapor deposition (CVD) on a silicon substrate to allow for improved sample preparation for antimicrobial experiments. 18 batches of 3 samples each (52 samples) were prepared by CVD coating silicon wafer substrates with alumina (400 nm) and iron (6 nm). Standard processes were generated for creating CICNT samples, with carbon nanotube (CNT) growth at 750 C and subsequent carbon infiltration at 900 C. In each batch, samples were positioned linearly with samples located centrally, downstream, and upstream in the furnace. Three batches had −20% gas flows (both hydrogen and ethylene), three batches had standard gas flows, and three batches had +20% gas flows. The experiment was then repeated with hydrogen flow held constant (only the ethylene was varied). Results showed that gas flow rates and sample position had negligible effects on nanotube height and diameter. This means that minor changes in gas flow rates and sample position do not have outsize effects on CICNT synthesis, which indicates that appropriate nanotube coatings can be prepared over a wide range of growth conditions.
