Field emission from carbon nanotubes produced using microwave plasma assisted CVD

Electron field emission from carbon nanotubes prepared using microwave plas ma assisted CVD has been investigated. The nanotubes, ranging from 50 to 12 0 nm in diameter and a few tens of microns in length, were formed under met hane and hydrogen plasma at 720 degrees C with the aid of iron-oxide partic les. The morphology and growth direction of the nanotubes are found to be s trongly influenced by the flow ratio of methane to hydrogen. However, the e lectron field emission from these massive nanotubes show similar characteri stics, i.e., high emission current at low electric fields.