TUNNELING EMITTER AND FORMING METHOD

PROBLEM TO BE SOLVED: To provide a flat emitter having a high energy current density and operating with high reliability in an environment of a low degree of vacuum. SOLUTION: An emitter has an electron supply layer and a tunneling layer formed on the electron supply layer. Optionally, an insulator layer is formed on the electron supply layer and has openings defined within a region in which the tunneling layer is formed. A cathode layer is formed on the tunneling layer. A conductive layer is partially disposed on the cathode layer and partially on the insulator layer if present. The conductive layer defines an opening to provide a surface for energy emissions of electrons and/or photons. Preferably but optionally, the emitter is subjected to an annealing process thereby increasing the supply of electrons tunneled from the electron supply layer to the cathode layer. COPYRIGHT: (C)2005,JPO&NCIPI