DIAMOND ELECTRON EMITTER AND ELECTRON BEAM SOURCE USING SAME

摘要

Disclosed is an electron emitter which is smaller in size, lower in operating voltage, and high in efficiency than the conventional ones. Also disclosed is an electron beam source using such an electron emitter. The electron emitter comprises a light-emitting element for irradiating a cathode with light, and at least electron-emitting surface of the cathode is composed of diamond. By having such a structure, the voltage for extracting electrons can be greatly lowered in this electron emitter than the conventional ones. Namely, there is obtained a small-sized electron emitter which can be operated at low voltage. The above-mentioned light-emitting element is preferably formed integrally with the cathode. The light-emitting element and the electrode are preferably composed of diamond. Further, it is desirable that the electron-emitting surface of the cathode is composed of an n-type or p-type diamond semiconductor.