Growth, structure and field emission characteristics of petal like carbon nano-structured thin films

Carbon films having large density of uniformly distributed petal like sheets have been synthesized by microwave plasma enhanced chemical vapor deposition using mixture of methane and argon gases on Ni coated Si substrates. The effect of microwave power on surface morphology has been investigated. Continuous increase in density and decrease in size of carbon petals with increasing microwave power have been observed by scanning electron microscopy. Raman spectroscopy of these films revealed characteristics of disordered microcrystalline graphite, which became more disordered with increase of microwave power. Possible growth mechanism of carbon nanopetals films has been discussed with time evolution of surface microstructure. Field emission measurements of carbon nanopetals films were also carried out showing the turn on field as low as 1.75 V/mu m. (c) 2005 Published by Elsevier B.V.