Abstract
A single-walled carbon nanotube (SWCNT) is a one-dimension material composed of graphene layer rolled up into a cylinder, with its end cap structure similar to the half of C60. SWCNT structure can be presented by their (m, n) indices, which determine SWCNT diameter and chirality. According tight-binding method calculation, SWCNT can be metallic, semiconducting or small-gap semiconducting, depending on their structure and diameters. For these SWCNT physical characteristics, the control of the diameter of SWCNT becomes the challenge of developing SWCNT-based nanoelectronic devices. In this thesis, a reliable method using chemical vapor deposition (CVD) method of growing high-purity SWCNTs was demonstrated. A high quality, almost bundle-free, SWCNTs with G/D area ratio of 55 was obtained by optimizing the catalytic system with SiO2(100 nm)/Al(15 nm)/Fe(1 nm)/Mo(0.2nm) multi-layer catalyst and the CVD growth process parameters. In addition, the sapphire wafer was utilized to be the substrate for SWCNT growth. Based on substrate effect to catalytic system, the growth of preferred diameter SWCNTs was demonstrated. Finally, we summarized these results by proposing a SWCNT growth mechanism with a growth model based on the lattice matching interaction (i.e. substrate effect to catalyst nanoparticles), the surface tension theory and the difference between surface and bulk diffusivities.