Characterization of Carbon Nano-Gap for Surface Conduction Electron Emitters

Field-emission displays (FEDs) retain the advantages of cathode-ray tubes (CRTs), namely, high color reproducibility, fast response, wide viewing angle, and high contrast level. The emitters used in FEDs are based on the principle that electrons are emitted by a strong electric field. It is necessary to obtain an electric field that is sufficiently strong to induce a tunnel current, even at a low voltage, by forming nanometer-sized gaps (nano-gaps) in the emitters. Previously, we formed a carbon nano-gap by our original method and reported that electrons can be stably emitted at a low voltage. In this study, we succeeded in forming a nano-gap with a uniform width by controlling the externally applied activation voltage by the same method. In addition, the strength of the electric field caused by the external voltage (V(f)), 0 x Vf, was found to be constant. In this paper, we discuss the mechanism underlying the formation of a carbon nano-gap and report electrical characteristics, temperature measurement data, and the results of observing cross-sectional images of the carbon nano-gaps obtained by scanning electron microscopy (SEM). In addition, the mechanism underlying the formation of the carbon nano-gap is modeled. (C) 2009 The Japan Society of Applied Physics