THEORETICAL-ANALYSIS OF FIELD-EMISSION FROM A METAL DIAMOND COLD-CATHODE EMITTER

Recently, Gels et al. [J. Vac. Sci. Technol. B 14, 2060 (1996)] propos ed a cold cathode emitter based on a Spindt-type design using a diamon d film doped by substitutional nitrogen. The device is characterized b y high field emission currents at very low power. Two properties, the rough surface of the metallic injector and the negative electron affin ity of the (111) surface of the diamond are essential for its operatio n. We present a first consistent quantitative theory of the operation of a Geis-Spindt diamond field emitter. Its essential features are pre dicated on nearly zero-field conditions in the diamond beyond the depl etion layer, quasiballistic transport in the conduction band, and appl icability of a modified Fowler-Nordheim equation to the transmission o f electrons through the Schottky barrier at the metal-diamond interfac e. Calculated results are in good qualitative and quantitative agreeme nt with the experimental results of Gels et al. (C) 1997 American Vacu um Society.