Growth of high-quality single-wall carbon nanotubes without amorphous carbon formation

We report an alternative way of preparing high-quality single-wall carbon nanotubes (SWCNTs). Using a triple-layer thin film of Al/Fe/Mo (with Fe as a catalyst) on an oxidized Si substrate, the sample is exposed to a single short burst (5 s) of acetylene at 1000 degreesC. This produced a high yield of very well graphitized SWCNTs, as confirmed by transmission electron microscopy and Raman spectroscopy. We believe that the high temperature is responsible for the high crystallinity/straightness of the nanotubes, and the rapid growth process allows us to achieve a clean amorphous carbon (a-C) free deposition which is important for SWCNT device fabrication. The absence of a-C is confirmed by Auger electron spectroscopy, Raman spectroscopy, and electrical measurements. (C) 2004 American Institute of Physics.