Field emission from nanoforest carbon nanotubes grown on cobalt-containing amorphous carbon composite films

Nanoforest carbon nanotubes (CNTs) were synthesized by biased thermal chemical vapor deposition on cobalt-containing amorphous carbon composite films. The composite films were deposited on silicon by filtered cathodic vacuum arc using a Co-containing graphite target and then CNTs were grown at 580 °C using the composite film as a catalyst layer. The nanoforest multiwalled CNTs have thin diameters between 10 and 20 nm. Their tips point upwards while the rest is densely tangled. They exhibit good field emission properties with a low threshold field of 1.6 Vμm and a high current density of 2.1 mA cm2 at 3 Vμm.