Improved field emission at electric-discharge-conditioned sites on diamond surfaces due to the formation of carbon nanotubes

The role of local materials modification to field emission (FE) from diamond is studied. FE properties of a boron-doped hydrogenated diamond film containing an array of sp(2) rich channels that extend from surface to substrate and of diamond films subjected to an electric discharge are reported. Whereas the implantation-graphitized regions do not show any improvement in emission properties, compared to unirradiated or fully irradiated regions of the same sample, much improved emission is found for all regions once conditioned by an electric discharge. We show that carbon nanowhiskers (most likely carbon nanotubes) were formed in the vicinity of all conditioned sites and can account for the improved emission following "conditioning" that have been reported for many carbon-based field emitters. (C) 2003 American Institute of Physics.