Skip to main content Accessibility help

Thin Film Dispenser Cathodes for Thermionic Micro-Devices

  • Kevin R. Zavadil (a1) and Donald B. King (a2)


Electron emissive thin films that possess the thermionic properties of macroscale dispenser cathodes have been fabricated using standard RF sputter deposition techniques. These films are based on a compositionally modulated structure using W and a Ba-containing ternary oxide. These films exhibit uniform work function values of 1.9 to 2.2 eV with high emission coefficients of 2 to 26 A·cm−2K−2. Electron microscopy shows that W layer coalescence and continued particle growth occurs with prolonged annealing, eventually disrupting the original surface layer. Chemical modification of the oxide during deposition may provide a route to limit the extent of W coalescence and preserve surface metallization layers on these films. These films are designed to be integrated into thermionic micro-devices.



Hide All
1. Herring, C. and Nichols, M.H., Rev. Mod. Phys., 21(2), 1949, 185270.
2. King, D.B., Zavadil, K.R. and Ruffner, J.A., 35th Intersociety Energy Conversion Engineering Conference Proceedings, American Institute of Aeronautics and Astronautics, July, 2000, 272282.
3. Thomas, R.E., Gibson, J.W., Haas, G.A. and Abrams, R.H., IEEE Trans. Electr. Dev., 37(3), 1990, 850861.
4. Gärtner, G., Geittner, P., Lydtin, H. and Ritz, A., Appl. Surf. Sci.,111(1997) 1117.
5. Zavadil, K.R., King, D.B. and Ruffner, J.A., Space Technology and Applications International Forum 2001, El-Genk, M.S., ed., AIP, Vol. 552, 2001, 11651170.

Thin Film Dispenser Cathodes for Thermionic Micro-Devices

  • Kevin R. Zavadil (a1) and Donald B. King (a2)


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed