Controlling growth and field emission property of aligned carbon nanotubeson porous silicon substrates

An aligned and well-distributed carbon nanotubes array was produced by pyro lysis of hydrocarbons catalyzed by nickel nanoparticles embedded in porous silicon (PS) substrates. Scanning electron microscope images show that the nanotubes form an aligned array approximately perpendicular to the surface of the PS substrate and the diameters of most of the tubes within the array are 10-30 nm. High-magnification transmission electron microscopy images c onfirmed that the nanotubes are well graphitized and typically consist of a bout 15 concentric shells of carbon sheets. Furthermore, the strong field e mission from the aligned carbon nanotubes emitter by pyrolysis of hydrocarb ons was observed. (C) 1999 American Institute of Physics. [S0003-6951(99)02 330-X].