Field emission spectroscopy from discharge activated chemical vapor deposition diamond

Electron field emission from vacuum-are discharge activated chemical vapor deposition diamond films has been investigated by measuring the current-vol tage characteristics and the field emitted electron energy distribution. Th e crater region created by the discharge has been investigated by atomic fo rce microscopy with simultaneous conductivity mapping. Comparison of the mo rphology and local conductivity in the activated zone with that of a good e mitting, nonactivated chemical vapor deposition diamond film, shows common features. Specifically these are a large surface roughness in the submicrom eter range and a drastically enhanced local conductivity. Both the activate d and nonactivated diamond emitters are characterized by strong "G" and "D" lines centered at 1590 and 1350cm(-1) wave numbers in the Raman spectrum. By the combined measurement of the field emission energy distribution and o f the current-voltage characteristics we determined the field enhancement f actor and the work function of the emitters independently. For the nonactiv ated diamond emitter we found a work function of 5.6 eV and for the activat ed diamond emitter 5.3 eV. These values correspond well with the 5 eV work function measured for nanotubes around. (C) 1999 American Vacuum Society. [ S0734-211X(99)07903-2].