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An electron emission behavior of field emission arrays based on a new bulk/surface silicon micromachining method of fabrication was studied. The process developed is simple and allows self-aligned gate electrode formation. The field emission of the emitter tips is enhanced by a 50 nm diamond-like carbon (DLC) film formed by chemical vapor deposition. Detailed Raman, Auger, and transmission electron microscopy (TEM) investigations of the deposited DLC films will be presented. Results about the presence of nanocrystalline diamond obtained with Raman spectroscopy could not be confirmed by the TEM investigations (the nanocrystalline diamond is smaller than 10 nm).

A theoretical analysis is made of the effect of field emission from films with a quantized electron spectrum. Dependences of emission current on film thickness demonstrate oscillatory behavior due to oscillations in screening constant. Certain critical thicknesses are found at which the jumplike changes in the value of field emission intensity occur. It is shown that a large positive effect (increase of the field emission efficiency) may be obtained for the case of nonplanar emitters covered by thin quantized films due to the superposition of two important factors (electric field strengthening near emitter tips and electron spectrum quantization in the film).

Polarization and barrier potentials for the point charge at a metal–vacuum interface have been calculated in the Thomas–Fermi and random phase approximations taking into account spatial dispersion effects and quantum nature of conduction electrons. The effect of external field penetration into the metal on the barrier potential shape and emission current is demonstrated. Both isotropic (a spherical Fermi surface) and anisotropic (a flat Fermi surface) cases are considered. Comparison between these cases is made for equivalent conditions.