Lithography-free synthesis of periodic, vertically-aligned, multi-walled carbon nanotube arrays

Abstract

Until now, the growth of periodic vertically aligned multi-walled carbon nanotube (VA-MWCNT) arrays was dependent on at least one lithography step during fabrication. Here, we demonstrate a lithography-free fabrication method to grow hexagonal arrays of self-standing VA-MWCNTs with tunable pitch and MWCNT size. The MWCNTs are synthesized by plasma enhanced chemical vapor deposition (PECVD) from Ni catalyst particles. Template guided dewetting of a thin Ni film on a hexagonally close-packed silica particle monolayer provides periodically distributed Ni catalyst particles as seeds for the growth of the periodic MWCNT arrays. The diameter of the silica particles directly controls the pitch of the periodic VA-MWCNT arrays from 600 nm to as small as 160 nm. The diameter and length of the individual MWCNTs can also be readily adjusted and are a function of the Ni particle size and PECVD time. This unique method of lithography-free growth of periodic VA-MWCNT arrays can be utilized for the fabrication of large-scale biomimetic materials.

Carbon Nanotube-Based Uncooled Bolometers: Advances and Progress

“…Parallelly, there have been positive efforts on the laboratory scale by other groups, such as low-temperature synthesis and lithography-free synthesis of periodic arrays, to grow these aligned forests with potential applications for optimal BMs. 183,184 Besides the introduction and development of new, unique device fabrication techniques and optimizing MWCNT forests, steps have also been taken to improve the bolometric performance with CNT hybrids. These hybrids include coupling CNTs with other nanomaterials, organic molecules, and so on.…”

“…Figure a shows the blackbody characteristics of various black coatings, and Figure b shows an SEM image of a CNT μBM pixel reported from the group. Parallelly, there have been positive efforts on the laboratory scale by other groups, such as low-temperature synthesis and lithography-free synthesis of periodic arrays, to grow these aligned forests with potential applications for optimal BMs. , …”

“…Figure21ashows the blackbody characteristics of various black coatings, and Figure21bshows an SEM image of a CNT μBM pixel reported from the group. Parallelly, there have been positive efforts on the laboratory scale by other groups, such as low-temperature synthesis and lithography-free synthesis of periodic arrays, to grow these aligned forests with potential applications for optimal BMs 183,184. Besides the introduction and development of new, unique device fabrication techniques and optimizing MWCNT forests, steps have also been taken to improve the bolometric performance with CNT hybrids.…”