High current density and long-life nanocomposite scandate dispenser cathode fabrication

IEEE Transactions on Electron Devices

Volumn 58, Issue 4, 2011, Pages 1221-1228

  Zhao, Jinfeng ^a   Li, Na ^c   Li, Ji ^c   Barnett, Larry R ^a   Banducci, Mike ^a   Gamzina, Diana ^a   Munir, Zuhair A ^b   Luhmann Jr , Neville C ^a  

^a UNIVERSITY OF CALIFORNIA   (United States)

^b University of California Davis   (United States)

^c BEIJING VACUUM ELECTRONICS RESEARCH INSTITUTE   (China)

Author keywords

Current density; nanosize; Sc2O3 added W

Indexed keywords

AVERAGE PARTICLE SIZE; DISPENSER CATHODES; EMISSION PROPERTIES; HIGH CURRENT DENSITIES; IMPREGNATED CATHODE; LIFE-TESTING; NANO-SIZED; NANO-STRUCTURED; NANOSIZE; PORE DISTRIBUTION; SC2O3-ADDED W; SCANDATES; SPACE-CHARGE-LIMITED CURRENT; TUNGSTEN GRAIN;

CURRENT DENSITY; ELECTRODES; NANOCOMPOSITES; POWDERS; SCANDIUM; TUNGSTEN;

THERMIONIC CATHODES;

EID: 79953116477     PISSN: 00189383     EISSN: None     Source Type: Journal    
DOI: 10.1109/TED.2011.2109723     Document Type: Article

References (29)

1. G. Gaertner and D. D. Engelsen, "Hundred years anniversary of the oxide cathode-A historical review," Appl Surf Sci., vol. 251, no. 1-4, pp. 24- 30, Sep. 2005. (Pubitemid 41537099)
2. 3mixed matrix impregnated cathodes," Appl. Surf. Sci., vol. 17, no. 4, pp. 517-529, Mar./Apr. 1984. (Pubitemid 14626195)
3. J. Hasker, J. Van Esdonk, and J. E. Crombeen, "Properties and manufacture of top-layer scandate cathodes," Appl. Surf. Sci., vol. 26, no. 2, pp. 173-195, Aug. 1986.
4. C. Crombeen, "Some experiment on the role of oxygen and surface reactions for tungsten and scandate thermionic emitters," IEEE Trans. Electron Devices, vol. 37, no. 12, pp. 2585-2588, Dec. 1990.
5. U. van Slooten and P. A. Duine, "Scanning auger measurements of activated and sputter cleaned Re-coated scandate cathodes," Appl. Surf. Sci., vol. 111, pp. 24-29, Feb. 1997. (Pubitemid 127388380)
6. J. Li, S. Yua, W. Shao, Q. Chen, and M. Zhu, "Investigation and application of impregnated scandate cathode," Appl. Surf. Sci., vol. 215, no. 1-4, pp. 49-53, Jun. 2003.
7. Y. Wang, J. Wang, W. Liu, K. Zhang, and J. Li, "Development of high current density cathodes with scandia-doped tungsten powders," IEEE Trans. Electron Devices, vol. 54, no. 5, pp. 1061-1070, May 2007. (Pubitemid 46691559)
8. J. Wang, L. Li, W. Liu, Y. Wang, L. Zhao, and Y. Wang, "Preparation and characterization of scandia and Re-doped tungsten matrix impregnated cathode," J. Phys. Chem. Solids, vol. 68, no. 12, pp. 2209-2215, Dec. 2007. (Pubitemid 350130259)
9. H. Yuan, X. Gu, K. Pan, Y. Wang, W. Liu, K. Zhang, J. Wang, M. Zhou, and J. Li, "Characteristics of scandate-impregnated cathodes with sub-micron scandia-doped matrices," Appl. Surf. Sci., vol. 215, no. 1-4, pp. 106-113, Sep. 2005. (Pubitemid 41537111)
10. J. Gibson, G. Haas, and R. Thomas, "Investigation of scandate cathodes: Emission, fabrication and activation process," IEEE Trans. Electron. Devices, vol. 36, no. 1, pp. 209-214, Jan. 1989.
11. I. P. Melinkova, V. G. Vorozheikin, and D. A. Usavov, "Correlation of emission capability and longevity of dispenser cathodes with characteristics of tungsten powders," Appl. Surf. Sci., vol. 215, no. 1-4, pp. 59-64, Jun. 2003.
12. 3and W," Appl. Surf. Sci., vol. 146, no. 1-4, pp. 31-38, May 1999.
13. Y. Wang, J. Wang, W. Liu, L. Li, Y. Wang, and X. Zhang, "Correlation between emission behavior and surface features of scandate cathodes," IEEE Trans. Electron. Devices, vol. 56, no. 5, pp. 776-785, May 2009.
14. J. Wang, Y. Wang, S. Tao, H. Li, J. Yang, and M. Zhou, "Scandia-doped tungsten bodies for Sc-type cathodes," Appl. Surf. Sci., vol. 215, no. 1-4, pp. 38-48, Jun. 2003.
15. S. Tao, Y. Wang, J. Wang, K. Pan, H. Li, X. Gu, and M. Zhou, "Microstructure and emission properties of Sc-type dispenser cathodes with scandia doped tungsten matrix," Vacuum Electron., vol. 247, no. 6, pp. 15-20, Jun. 2003.
16. 311x Impregnated cathodes and TZM heaters were manufactured by, Watsonville, CA.
17. AnalySIS Software, Soft Imaging Syst. Corp., Lakewood, CO.
18. R. E. Thomas, J. W. Gibson, G. A. Haas, and R. H. Abrahams, "Thermionic sources for high-brightness electron beams," IEEE Trans. Electron. Devices, vol. 37, no. 3, pp. 850-861, Mar. 1990.
19. R. T. Longo, "Physics of thermionic dispenser cathode aging," J. Appl. Phys., vol. 94, no. 10, pp. 6966-6975, Nov. 2003.
20. D. Windes, J. Dutkowski, R. Kaiser, and R. Justice, "Triservice/NASA cathode life test facility," Appl. Surf. Sci., vol. 146, no. 1-4, pp. 75-78, May 1999.
21. R. Jardieu and R. Macior, "Cathode life prediction," ARC Professional Services Group, Rome, NY, Final Tech. Rep. RL-TR-91-321, Dec. 1991.
22. G. Schietrum, G. Caryotakis, N. Luhmann, Y. Wang, J. Li, G. Miram, and B. Vancil, "100 A/cm2 tungsten-scandate nanopowder thermionic cathode testing at SLAC," in Proc. Multidisciplinary Univ. Res. Initiative Annu. Rev., Monterey, CA, Apr. 2006.
23. This M-type cathode was coated by Communications & Powder Industries (CPI) using Spectra-Mat cathode.
24. 3-added tungsten powder was tested by Galbraith Laboratories, Elemental Analysis Inductively Coupled Plasma (ICP) method (Knoxville, TN).
25. S. E. Tsimring, Electron Beams and Microwave Vacuum Electronics. Hoboken, NJ: Wiley, 2007.
26. R. True, "Electron beam formation, focusing, and collection in microwave tubes," in Handbook of Microwave Technology: Components and Devices, T. K. Ishii, Ed. New York: Academic, 1995, ch. 14, pp. 494-567.
27. J. Atkinson, D. Gajaria, T. Grant, T. Kimura, B. Stockwell, M. Field, R. Borwick, III, B. Brar, and J. Pasour, "A high aspect ratio, high current density sheet beam electron gun," in Proc. IEEE Int. Vacuum Electron. Conf., 2010, pp. 97-98.
28. D. Gamzina, A. G. Spear, L. R. Barnett, and N. C. Luhmann, Jr., "Terahertz sheet beam gun analyzer," in Proc. IEEE Int. Vacuum Electron. Conf., 2010, pp. 99-100.
29. DARPA HiFIVE (High Frequency Integrated Vacuum Electronics) program through a subcontract with Teledyne Scientific, grant No. G8U 543 366.