Electron source

摘要

A high brightness, essentially monoenergetic electron source is constructed in solid state material by providing a semiconductor body with an electron confinement barrier over most of the surface, the barrier having a relatively small opening exposing the semiconductor body, in the relatively small opening a material is placed in contact with the semiconductor body that has a work function that is lower than the energy of excited electrons in the semiconductor. In this structure electrons from hole-electron pairs generated in the semiconductor are repelled and recombination is inhibited by the barrier except in the relatively small opening where they are injected into the surrounding environment through the lower work function material. The hole-electron pair generation may be by irradiation or by electrical injection. The electron source is useful for such applications as high brightness sources, digital communications, cathode ray tube electron sources and scanning electron microscopes.