Field emission properties of porous diamond-like films produced by chemical vapor deposition

The field emission properties of porous diamond-like carbon structures have been characterized. A hot filament chemical vapor deposition system fed with ethyl alcohol vapor diluted in helium was used to deposit the samples. Morphological analysis by field emission scanning electron microscopy revealed that they had a highly porous structure, which was attributed to the modification of the kinetics of the carbon deposition process due to the presence of helium as a buffer gas. Micro-Raman spectroscopy showed two peaks in the graphene and microcrystalline graphite frequencies and a new peak at 1620 cm(-1). Low threshold fields (E-t) and hysteresis in the current versus voltage characteristic have been observed, and a model to explain the hysteresis is proposed. (C) 2002 American Institute of Physics.