Electron field emission (FE) from quantum size systems

The shape of the potential barrier at a thin-film cathode with a quantized electron spectrum is investigated theoretically taking into account spatial dispersion effects, external field penetration and collective Fermi-liquid interactions in the system of filled electron states. Quantum size effects lead to quasi-oscillatory dependences of screening radius, affinity energy, work function, barrier height and external field penetration into the film on film thickness. As a result of these effects, at some critical thicknesses which are characteristic for the film material, the emission current from a thin-film cathode is predicted to be substantially greater (by some orders of magnitude) than that from the non-quantized bulk material.