ELECTRON SOURCE OF ELECTRIC FIELD EMISSION TYPE

摘要

PURPOSE: An electron source is provided to restrain electric currents of a diode and to enhance an electron emitting efficiency by forming a layer having consecutively changing porous degrees. CONSTITUTION: A main surface of an n-type silicon substrate(101) is formed with a strong electric field drift part(106), and a surface electrode(107) is formed on the strong electric field drift part(106) with a gold thin film. An ohmic contact(107) is formed on the rear side of the n-type silicon substrate(101). The surface electrode(107) is disposed in a vacuum state, and the surface electrode(107) has a positive pole over the ohmic electrode(102) to apply a direct voltage. Electrons injected in the n-type silicon substrate(101) drifts the strong drift part(106) to be emitted through the surface electrode(107).