Effects of atomic-scale surface morphology on carbon nanotube alignment on thermally oxidized silicon surface

We have investigated the effects of atomic-scale surface morphology on the single-walled carbon nanotube (SWNT) growth by using atomic step-structure-controlled SiO 2 / Si substrates. SWNTs initially extended randomly on the surface, and when they became longer than 3 μ m , they followed the atomic step morphology with a height of 0.6 nm. This indicates that SWNT extension along the surface is greatly affected by the surface morphology of the substrate. The present results also explain why the SWNT orientation on a normal SiO 2 / Si surface is random. SWNTs extend along the surface morphology based on the roughness of the SiO 2 surface.