Field emission characteristics of nanostructured thin film carbon materials

Nanostructured carbon (nC) thin film materials were obtained by chemical vapor deposition (CVD) in dc discharge activated hydrogen–methane gas mixture. Film structure, surface morphology and phase composition was studied by Raman, electron microscopy and electron spectroscopy methods. A highly efficient cold electron emission was found for the films composed from graphite-like nano-structures including carbon nanotubes (CNT) and graphite nano-crystallites. Electron emission tests and analysis exhibit non-classical behavior of the nano-carbon cold cathodes. The statistical analysis of the cold emission show normal distribution of parameters of separate emission centers with narrow standard deviation. The possible mechanism of the cold emission is discussed. The highest efficiency of the nano structured carbon cathodes is demonstrated in the prototypes of vacuum cathodoluminescent lighting devices.