Instability of the emission current of a cathode based on carbon fibers
Abstract Carbon materials used as field electron cathodes refer to nanostructured materials. Field emission of such materials occurs with micro-protrusions having characteristic sizes from 0.1 to 100 nm. Field emission cathodes made of carbon materials are currently used in various fields of vacuum electronics. Carbon can be in various forms: for example, graphite, amorphous carbon, fullerenes, nanotubes. One of the many types of carbon materials are polyacrylonitrile carbon fibers (PAN). Such types of carbon materials are widely used for manufacturing cathodes with field emission for general purposed lamps [1]. This paper will discuss the method of plasma-chemical treatment with a corresponding apparatus and instability of field emission current from the cathode based on carbon fiber (PAN). After etching process of the cathode, a cathode with modulator using a carbon-fiber field emitter has been constructed and produced field emission current. We have performed some test of the field emission fluctuations from a carbon-fiber field emitter and examined the instability of the current at a system pressure of 10 -6 torr.