Laser Patterning of Aligned Carbon Nanotubes Arrays: Morphology, Surface Structure, and Interaction with Terahertz Radiation.

Olga V Sedelnikova,Polina P Kuzhir,Gleb V Gorokhov,Dmitriy V Gorodetskiy,Anna A Makarova,Sergey A Maksimenko,Kseniya I Baskakova,Dzmitry S Bychanok,Alexander G Kurenya,Elena V Shlyakhova,Alexander V Okotrub,Lyubov G Bulusheva

doi:10.3390/ma14123275

Abstract

The patterning of arrays of aligned multi-walled carbon nanotubes (MWCNTs) allows creating metastructures for terahertz (THz) applications. Here, the strips and columns from MWCNTs vertically grown on silicon substrates are prepared using CO2 laser treatment. The tops of the patterned arrays are flat when the laser power is between 15 and 22 W, and craters appear there with increasing power. Laser treatment does not destroy the alignment of MWCNTs while removing their poorly ordered external layers. The products of oxidative destruction of these layers deposit on the surfaces of newly produced arrays. The oxygen groups resulting from the CO2 laser treatment improve the wettability of nanotube arrays with an epoxy resin. We show that the patterned MWCNT arrays absorb the THz radiation more strongly than the as-synthesized arrays. Moreover, the pattern influences the frequency behavior of the absorbance.

Highlights

Carbon nanotubes (CNTs) possess exceptionally high terahertz (THz) conductivity and, can replace the bulk metallic components and nanowires in nanoelectronics [1], communications [2,3], medicine [4], and many others [5,6]
The image taken from a crack of one of the columns showed a good ordering of the interior multi-walled carbon nanotubes (MWCNTs) (Figure 1j), the same as the initial array
Burning holes in the column centers under processing with higher laser power suggested that even the internal MWCNTs, which were not directly exposed to the beam, were modified during the engraving

Summary

Introduction

Carbon nanotubes (CNTs) possess exceptionally high terahertz (THz) conductivity and, can replace the bulk metallic components and nanowires in nanoelectronics [1], communications [2,3], medicine [4], and many others [5,6]. A few techniques allow obtaining patterned growth of aligned CNT areas, such as templating of a substrate to define the patterns of catalytic layers [12,13] or using lithography [14,15,16] followed by the conventional chemical vapor deposition (CVD) synthesis of nanotubes. Another technique is the post-growth treatment based on the ablation of an array by a focused laser beam. With the need to scan a large area and reduce the overall cost of material, a high-power continuous laser seems to be the best choice for the patterning technology of CNT arrays

Methods

Results

Conclusion