Title :
Investigation of scandate cathodes: emission, fabrication, and activation processes
Author :
Gibson, John W. ; Haas, George A. ; Thomas, Richard E.
Author_Institution :
US Naval Res. Lab., Washington, DC, USA
fDate :
1/1/1989 12:00:00 AM
Abstract :
Top-layer cathodes have been shown to exhibit work function values in the 1.5-eV range near 1100 K. Emission from cathodes made by sputter deposition of a Sc2O3/W layer on top of an impregnated cathode were limited by the deposition conditions that cause dissociation of Sc2O3 and/or formation of volatile oxides of W. Pure Sc2O3 layers were also activated by an external Ba source to the value of the work function reported above. These results and activation mechanisms and characteristics that are peculiar to the Ba-O-Sc surface are discussed
Keywords :
scandium compounds; sputter deposition; thermionic cathodes; thermionic electron emission; tungsten; 1.5 eV; 1100 K; Ba-O-Sc surface; Sc2O3-W layer; activation mechanisms; activation processes; characteristics; deposition conditions; dissociation of Sc2O3; emission; external Ba source; fabrication; impregnated cathode; sputter deposition; volatile oxides; work function values; Cathodes; Extrapolation; Fabrication; Geometry; Laboratories; Plugs; Sputtering; Temperature; Testing; Thermionic emission;
Journal_Title :
Electron Devices, IEEE Transactions on
