Field emission source with plural emitters in an opening

摘要

A field emission electron source capable of achieving large current density is provided at low cost with good productivity. An insulating layer is formed on a substrate and has one or more openings; and an extraction electrode is formed on the insulating layer. In one or more of the openings, a plurality of emitters, each of which emits an electron by an electric field from the extraction electrode, are formed on the substrate.