A review of oxide cathode research in IECAS

Summary form only given. Oxide cathode is invented, developed and applied in vacuum electronic devices over 100 years. This paper presents a review for the research results of the emission mechanisms, characteristics and applications of the oxide cathode in IECAS, which includes a dynamical surface emission center theory, a high reliable and long lifetime oxide cathode, as well as a low temperature' and large emission current oxide cathode. The characteristics of these cathodes, such as, DC and PC emission, evaporations, resistance to poisoning and lifetime, are discussed. These cathodes have been wildly applied in communication secondary planet TWT, high power wide pulse klystrons and high operating ratio TWT, which shows that good characteristics for the emission and lifetime can been reached.