New high-intensity point electron source

The paper presents a new physical technology to produce self-assembled nanoheterostructures formed in thin (~5-10 nm) (ZrO2) dielectric layers at the surface of pointed W microcrystals. The studies of thermally activated electron emission from the ZrO2-vacuum interface into vacuum under electrostatic field have shown that the electron emission behavior does not agree with the thermal field emission theory. The phenomenon studied was called the abnormal thermal field emission. It has been found that the normalized brightness and angular intensity of emission from the nanoheterostructure surface are two orders of magnitude higher than those of ZrO/W Schottky cathodes. A phenomenological model for the mechanism of thermal field emission is offered.