am9b15060_si_001.pdf (1.58 MB)
Aerosol-Jet-Printed Preferentially Aligned Carbon Nanotube Twin-Lines for Printed Electronics
journal contribution
posted on 2019-11-08, 22:29 authored by Guo Liang Goh, Shweta Agarwala, Wai Yee YeongThe
alignment of carbon nanotubes (CNTs) is of great importance
for the fabrication of high-speed electronic devices such as a transistor
as the electron mobilities can be greatly enhanced with aligned CNT
architectures. Here, we report, for the first time, a methodology
to obtain preferentially aligned CNT traces on a flexible polyimide
substrate utilizing the high-resolution aerosol jet printing technique
and evaporation-driven self-assembly process. A self-assembled twin-line
of CNT (“coffee-ring” effect) is observed in the deposit
patterns, and the field-emission scanning electron microscopy (FESEM)
images reveal highly self-ordered CNT in the resulting CNT twin-line.
Various aerosol jet parameters have been investigated to obtain printed
tracks in the range of 30–80 μm and conductive tracks
(single CNT twin-line width) in the range of 600–1500 nm. The
smallest CNT twin-line obtained in this experiment is found to be
approximately 16 μm using a suitable sheath-to-atomizer flow
ratio. Image analysis of FESEM images confirms the formation of aligned
CNT traces at the ink periphery. The effect of the line width on the
degree of alignment of the CNT is studied and evaluated. The electrical
resistance of the CNT trace is adjustable by controlling the number
of print passes and print speed.