Field Electron Emission from Metals

Abstract

The field emission (FE) process is a unique type of electron emission as it is due exclusively to quantum-mechanical effects—tunneling of electrons into vacuum. This phenomenon occurs in high electric fields. This phenomenon occurs in high electric fields 10⁷− 10⁸ V/cm. In order to produce such high fields using reasonable potentials the emitter is usually formed into a tip with the apex radius of curvature ranging from tens of angstroms to several microns. The high electric field narrows the potential barrier at the metal-vacuum interface sufficiently for the electrons to have a significant probability of tunneling from the solid into the vacuum.