Facile “Needle‐Scratching” Method for Fast Catalyst Patterns Used for Large‐Scale Growth of Densely Aligned Single‐Walled Carbon‐Nanotube Arrays

Abstract

Scratching the surface: A simple needle‐scratching method (NSM) generates large‐area catalyst patterns on solid substrates for the growth of densely aligned single‐walled carbon‐nanotube (SWCNT) arrays by chemical vapor deposition (CVD, see picture). A high density of well‐aligned, ultralong SWCNTs is obtained on single‐crystal quartz. This NSM could allow the fast, cheap, and large‐area fabrication of CNT‐based nanodevices.

Improved Density in Aligned Arrays of Single‐Walled Carbon Nanotubes by Sequential Chemical Vapor Deposition on Quartz

“…However, experiments show clearly that this method is ineffective because SWNTs that originate from one catalyst line cannot pass through another catalyst line (see the Supporting Information). This behavior results from the near‐surface growth mode observed in these systems, in which even very slight relief, associated with either with misaligned SWNTs or with catalyst particles, can terminate the growth 17, 18–19. As a result, the SWNT density does not depend strongly on catalyst line separation, provided that this separation is substantially less than the average lengths of the grown SWNTs (e.g., between 200 and 500 µm for typical cases).…”

Ordered Arrays of Carbon Nanotubes: From Synthesis to Applications

“…[32] They show that a high density of wellaligned (up to 10 tubes mm -1 ) and ultra long SWCNTs (up to 0.5 mm) could be obtained on quartz. Another similar work by group of Bilu Liu [33]from Shenyang National Laboratory for Materials Science suggested that the "scratching" between two Si/SiO 2 wafers will make the thermally grown SiO 2 layer crack and consequently generate some active sites, which have some similarities to the SiO 2 film by sputtering deposition, thus facilitating the growth of SWNTs.…”

Carbon-nanotube-based RF components with multiple applications

“…4) that could be used for planar antennas, such as the illustrated dipole. We use a quick and low-cost scratch catalyst technique [4] as opposed to lithography patterning and e-beam evaporation of metal catalyst. Although fast and cheap, the technique is difficult to systematize and scale.…”