Abstract
We have developed manufacturable approaches to form single, vertically aligned carbon nanotubes,
where the tubes are centered precisely, and placed within a few hundred nm of 1-1.5 μm deep trenches.
These wafer-scale approaches were enabled by chemically amplified resists and inductively coupled
Cryo-etchers to form the 3D nanoscale architectures. The tube growth was performed using dc plasmaenhanced
chemical vapor deposition (PECVD), and the materials used for the pre-fabricated 3D
architectures were chemically and structurally compatible with the high temperature (700 °C) PECVD
synthesis of our tubes, in an ammonia and acetylene ambient. The TEM analysis of our tubes revealed
graphitic basal planes inclined to the central or fiber axis, with cone angles up to 30° for the particular
growth conditions used. In addition, bending tests performed using a custom nanoindentor, suggest that
the tubes are well adhered to the Si substrate. Tube characteristics were also engineered to some extent,
by adjusting growth parameters, such as Ni catalyst thickness, pressure and plasma power during growth.
