In situ growth of single-walled carbon nanotubes by bimetallic technique with/without dielectric support for nanodevice applications

Abstract

Articles you may be interested inGrowth and characterization of carbon nanotubes on constantan (Cu-Ni-Mn alloy) metallic substrates without adding additional catalystsThe single-walled carbon nanotubes ͑SWNTs͒ have been considered as an alternative material for nanoelectronics, such as field-effect transistor or nanosensor, due to their unique electronic properties. However, an in situ growth process that can synthesize SWNTs with good position, diameter, and directional control is not yet available. Recent developments on the synthesis of SWNTs by deposition of ultrathin catalyst metal on the support of high specific areas were quite encouraging. In this study, high-yield vertically aligned SWNT arrays are demonstrated by in situ growth process with/without dielectric support material. In the case with dielectric support material, the role of dielectric support layer and the mechanisms of SWNT growth control will be discussed. Then, in the case without dielectric support material, the iron-based catalytic system revealed the ability to grow SWNTs from single-crystal silicon wafer directly, giving rise to the possible application of device structure with specific process module, for example, vertically aligned carbon nanotube field-effect transistor device may need to grow SWNT from doped-silicon area ͑source or drain well͒. In these experiments, micro-Raman spectroscopy and high-resolution transmission electron microscopy were utilized to characterize the SWNT properties and structures.

Large-scale growth of single-walled carbon nanotubes using cold-wall chemical vapor deposition

“…12 In this study, a multilayered catalytic system ͓͑Al ͑15 nm͒/Fe ͑1 nm͒/Mo ͑0.2 nm͔͒ deposited on the Si/ SiO 2 substrate was adopted based on our previous study, 13 and the AFM and AES were utilized to examine the surface morphology and element depth profile of the multilayered catalytic system before and after pretreatment. From the tapping mode AFM height image, the flat surface of the metal stack ͓Al ͑15 nm͒/Fe ͑1 nm͒/Mo ͑0.2 nm͔͒, before pretreatment, was shown in Fig.…”

Direct synthesis of single-walled carbon nanotubes selectively suspended on tips of vertically aligned silicon nanostructures fabricated by hydrogen plasma etching

“…Multilayered thin films (Mo0.5/Fe1/Al10; numbers in the unit of nm) were first deposited by a conventional electron-beam evaporation method on substrates, either bare or thermally oxidized p-type Si(100) wafers (referred to as Si or SiO 2 substrates, in figure 1(a)) depending on the materials of the Si-nss to be formed. The growth mechanism of SWNTs by such multi-layered catalyst system has been widely investigated [26][27][28], and thus will not be further discussed here. The multi-layered thin films were then thermally annealed in a hydrogen atmosphere to form nanoscale islands or particles (figure 1(b)) as a result of the reduced melting temperature at low dimensions and scales.…”

Synthesis of Carbon Nanotubes by Catalytic Chemical Vapor Deposition

“…Shin et al [62] used Ni-based and Fe-based catalytic systems, and high-yield synthesis of SWCNTs was demonstrated. It is more difficult to synthesize SWNTs with a low temperature in nickel-based catalyst system than in iron-based catalyst system.…”