Selective placement of single-walled carbon nanotubes on pre-defined micro-patterns on SiO₂ surface based on a dry lift-off technique

We reported a new technique for self-assembly of selective placement of carbon nanotubes (CNT) on pre- defined micro-patterns. Our work based on the use of a poly-para-xylylene C passivation layer on silicon dioxide (SiO₂) surface which was micro-patterned by reactive ion etching (RIE) process and follow by the CNT deposition step. The lift-off of poly-para-xylylene layer then was carried out relying on a dry lift-off method in order to remove the nanotubes adsorbed on the poly-para-xylylene layer leaving the CNT on the desirable areas. CNT located at specific micro-areas with pre-defined patterns from 50 μm down to less than 10 μm line width and variable shapes. This approach provides a simple and useful means allow controlled placement of CNT which is necessary for the large-scale fabrication of electronic devices.