Controlled Growth of Carbon Nanotubes and Its Field EmissionProperties

Uniform films of aligned carbon nanotubes were grown on a patterned Ni coated ceramic substrate by microwave plasma chemical vapor deposition (MWPCVD). A laser writing technique was used to make some patterns on the substrate. The controlled selective growth of nanotubes on the patterned substrate can be obtained directly during the reaction process in the MWPCVD chamber. The Raman spectrum shows a good graphitization of the carbon nanotubes. In the field emission test, turn-on field of V/μm and emission current density of 5 mA/cm² at 3.3 V/μm were achieved.