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Nonevaporable Getters: Properties and Applications

Published online by Cambridge University Press:  29 November 2013

F. Mazza  and
C. Boffito
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Many advanced technologies, such as surface science, semiconductor processing and high energy physics, call for vacuum levels of the order of 10−11 mbar and lower. These pressures can not be reached without a careful choice of materials, treatments, and evacuation means for the vacuum device involved. Non-evaporable getters (NEGs) are increasingly being recognized as an interesting and powerful solution for many vacuum problems. NEGs have been used extensively in sealed-off devices such as microwave tubes, traveling wave tubes, x-ray tubes, lamps, and infrared detector dewars, in which their main role is to assure the desired vacuum level throughout the life of the sealed device. The getter material can be considered as a chemical pump which removes the active gases in the residual atmosphere of the vacuum device by forming stable chemical compounds.

The choice of materials, treatments, and structures of nonevaporable getter materials is critical for the optimization of the sorption and diffusion processes which are the basis of the NEG pumping mechanism. The effectiveness of this pumping mechanism at very low pressures, and the cleanliness and simplicity of operation have made this pumping approach ideal, in combination with other pumping technologies, for reaching the extreme high vacuums today's advanced technologies require. This article will explain the mechanism of the gettering process, describing materials, treatments, and structures used in standard vacuum practice, and will review some of the most typical and interesting applications.

Type
Materials for Vacuum
Information
MRS Bulletin , Volume 15 , Issue 7 , July 1990 , pp. 50 - 52
Copyright
Copyright © Materials Research Society 1990

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References

1.Ichimura, K., Ashida, K., and Watanabe, K., J. Vac. Sci. Technol. A3 (1985) p. 362Google Scholar
2.Ichimura, K., Matsuyama, M., and Watanabe, K., J. Vac. Sci. Technol. A5(2) (1987) p. 220.CrossRefGoogle Scholar
3.Meli, F., Sheng, Z., Vedel, I., and Schupbach, L., paper presented at the 11th International Vacuum Congress, Cologne, Sept. 2529, 1989, to be published in Vacuum.Google Scholar
4.Kroontje, W., De Maagt, B.J., van Rijswick, M.H.J., and Sprenger, L., J. Vac. Sci. Technol. A4(5) (1986) p. 2293CrossRefGoogle Scholar
5.Verhoeven, J. and van Doveran, H., J. Vac. Sci. Technol. 20(1) (1982) p. 64.CrossRefGoogle Scholar
6.Bofhto, C., Ferrario, B., della Porta, P., and Rosai, L., J. Vac. Sci. Technol. 18 (1981) p. 1117CrossRefGoogle Scholar
7.Barosi, A. and Giorgi, T.A., Vacuum 23 (1973) p. 15.CrossRefGoogle Scholar
8.Ferrario, B., Figini, A., and Borghi, M., Vacuum 35 (1984) p. 13.CrossRefGoogle Scholar
9.Giorgi, E., Ferrario, B., and Boffito, C., J. Vac. Sci. Technol. A7(2) (1989) p. 218.CrossRefGoogle Scholar
10. ASTM Standard F 798-82.Google Scholar
11.Giorgi, T.A., Ferrario, B., and Storey, B., J. Vac. Sci. Technol. A3 (1985) p. 417.CrossRefGoogle Scholar
12.Gilmour, A.S. Jr., Microwave Tubes (Artech House, Dedham, 1986) p. 62–66.Google Scholar
13.Mathewson, A.G., Synchrotron Radiation News 3(1) (1990) p. 13.CrossRefGoogle Scholar
14.Reinhard, H.P., Proc. IX IVC-V ICSS, Madrid (1983) p. 273.Google Scholar
15. LEP Vacuum Group, paper presented at the 11th International Vacuum Congress, Cologne, Sept. 25-29, 1989, to be published in Vacuum.Google Scholar
16.Wehrle, A.R., Nielsen, R., and Kim, S., Proc. 1989 IEEE Particle Accelerators Conference, Vol. 1, Chicago, March 20-23, 1989, p. 583.CrossRefGoogle Scholar
17.Be, S.H., Yokouchi, S., Morimoto, Y., Sakamoto, H., Lee, J.P. and Oikawa, J., Proc. 1989 IEEE Particle Accelerators Conference, Vol. 1, Chicago, March 20-23, 1989, p. 577.CrossRefGoogle Scholar
18.Trickett, B.A., Vacuum 38 (1988) p. 607.CrossRefGoogle Scholar
19.Schuchman, J.C., paper presented at the 11th International Vacuum Congress, Cologne, Sept. 25-29, 1989, to be published in Vacuum.Google Scholar
20.Ferrario, B., Borghi, M., Cecchi, J., and Sredniawski, J., Proc. 11th SOFT, Oxford, Sept. 15-19, 1980 (Pergamon Press, 1981) p. 375.Google Scholar
21.Ando, T., Nakamura, H., Yoshida, H., Sunaoshi, H., Arai, T., Akino, N., Hiroki, S., Yamamoto, M., Ohkubo, M., Shimizu, M., and Kondo, I., Fusion Technology 1 (1986) p. 615.Google Scholar
22.Walker, C.I., Kaye, A.S., Horn, R.A., and Mazza, F., Fusion Technology 1 (1986) p. 815.Google Scholar
23.Bonizzoni, G., Conte, A., Gatto, G., Gervasini, G., Ghezzi, F., and Rigamonti, M., paper presented at the 11th International Vacuum Congress, Cologne, Sept. 25-29, 1989, to be published in Vacuum.Google Scholar
24.Audi, M., Dolcino, L., Doni, F., and Ferrario, B., J. Vac. Sci. Technol. A5(4) (1987) p. 2587.CrossRefGoogle Scholar
25.Briesacher, J., Toyoda, N., Boffito, C., and Doni, F., Proc. 10th Symp. on ULSI Ultra Clean Technology, Kyoiku Kaikan, Nov. 9-10, 1989.Google Scholar