Surface chemical analysis of cesium-iodide (CsI) coated carbon (C) fibers and thin films for field emission applications

Carbon (C) fibers with electron emission enhancing cesium iodide (CsI) surface coatings are utilized as field emission cathodes and have been investigated as promising electron sources. Possible applications include not only High Power Microwave (HPM) devices, but also conventional microwave devices, x-ray tubes, and field emission displays. Upon appropriate conditioning of the cathode to remove adsorbed water vapor, stable operation for more than one million pulses, little or no plasma formation, and low turn on E-fields, compared to un-coated C fibers, have been observed.