FLUCTUATION-FREE ELECTRON-EMISSION FROM NON-FORMED METAL-INSULATOR-METAL (MIM) CATHODES FABRICATED BY LOW CURRENT ANODIC-OXIDATION

Fluctuation-free electron emission is obtained from MIM (Al-Al2O3-Au) cathodes. The Al2O3 layer is fabricated by anodic oxidation with a reduced electrolysis current density, i.e., a reduced oxidation rate. The slow oxidation process improves the insulating effect of the Al2O3 layer, and enables the MIM cathodes to operate in the non-formed state. The fluctuation-free emission is reproducible when the diode voltage is cut off instantaneously. With a thin Al2O3 layer, the diode voltage reguired for the cathode operation is reduced to values slightly above the work function of the top electrode.