Cold cathode based on a formed metal-insulator-metal structure

Hybrid vacuum integrated circuits operating in the UHF range is one application where cold cathodes with high current density are needed. The cold cathode based on the formed metal-insulator-metal (MIM) structure is a kind of field emitter and it can be potentially used for some UHF applications. Formed MIM cathodes have demonstrated current densities up to 0.5 A/cm/sup 2/, but these values are low and have to be improved. Forming is the final step of MIM cathode fabrication strongly affecting its emission characteristics. Despite the fact that numerous work has been done in this field, many aspects of the forming process still remain unclear. The present paper reports some new results on studying the forming process in MIM systems.