On the mechanism of stabilization of low-field electron emission from dielectric films on metals

We have carried out a comparative study of the low-field electron emission (LFEE) from a range of dielectric films such as a-C, i-C, ZnS, SiO₂ and some others. The results suggest the existence of a common mechanism governing LFEE from dielectric films on metals. It is concluded that the slope of the FN plots in the high-current (stable) range of LFEE depends on the shape of the interface (metal/dielectric) barrier as well as on the thickness and band structure of the film. In this case the “working region” of the emitter is not exposed to vacuum, which provides the high stability of LFEE even at mTorr pressures as found in our experiments