Fabrication of Vertically Aligned Carbon Nanotubes on MgO Support Layer by Thermal Chemical Vapor Deposition for Field Emission Application

Vertically aligned multiwalled carbon nanotubes (MWCNTs) were synthesized by simple thermal chemical vapor deposition on MgO support layer. MgO layer was deposited on Si (001) wafer by magnetron sputtering. With acetylene as carbon source and iron as catalyst vertically aligned multiwalled carbon nanotubes have been grown at 700 degrees C by our home made thermal chemical vapor deposition setup. As synthesized MWCNTs have been characterized by field emission scanning electron microscopy, transmission electron microscopy and confocal Raman spectroscopy. Field emission characteristic of vertically aligned MWCNTs forest was measured by our home made field emission setup and showed good field emission properties. Turn-on and threshold field have been obtained as 0.56 V/mu m (at J= 10 mu A/cm(2)) and 3.83 V/mu m (at J=1 mA/cm(2)) respectively from vertically aligned MWCNTs. Field emission characteristic was explained on the basis of follows the Fowler-Nordheim (F-N) equation.