Cold hollow cathodes have the capability to provide high current density electron emission in gaseous atmosphere. In recent years, it has been used in plasma switches for conduction of kilo amperes of current. Another type of hollow cathodes, which are thermionic emitter based, has been in use in high power Thyratron switches. In the present work oxide coated cathode based hollow cathodes have been fabricated. These cathodes have been used for the development of prototypes of hydrogen/ deuterium Thyratrons operating at gas pressure 0.5-0.8 mbar. The cathodes have first been tested in demountable diodes for evaluation of discharge current characteristics under varying gas pressure. The peak current ratings of these cathodes can be extended depending upon pulse width, pulse repetition requirements and associated thermionic cathode type. The fabrication schedule of these cathodes involves empirical design, assembly, vacuum processing, activation and processing under gaseous atmosphere. The paper discusses the main features of the processes involved and results.
展开▼
