A method for fabricating an electron emitter. This emitter structure may be used to form individual emitters or arrays of emitters. The method is comprised of implanting energetic ions into a diamond lattice to form cones or other continuous regions of damaged diamond. These regions are more electrically conducting than the surrounding diamond lattice, and have locally sharp tips at or near the point of entry of the ion into the diamond. The tips may then also be additionally coated with a layer of a wide band-gap semiconductor. An electrically conducting material may also be placed in proximity to the tips to generate an electric field sufficient to extract electrons from the conducting tips into either the region above the surface, or into the wide band-gap semiconductor layer in contact with the tips. Electrical contact is made to the electrically conducting damage tracks and the electrical circuit may be completed with an electrically conducting material on the surface of the wide band-gap semiconductor or diamond, or in the ambient above the surface of the emitter. The surface of the wideband gap semiconductor or diamond may be chemically modified to enhance the emission of electrons from the surface.