Hostname: page-component-586b7cd67f-2brh9 Total loading time: 0 Render date: 2024-11-25T18:46:25.583Z Has data issue: false hasContentIssue false

Structire, Properties, and Process Characteristics of Low-K Materials Prepared by PECVD

Published online by Cambridge University Press:  10 February 2011

Y. Shimogaki
Affiliation:
Department of Metallurgy, University of Tokyo 7–3-1 Hongo, Bunkyo-ku, Tokyo 113–8656, JAPAN, [email protected]
S. W. Lim
Affiliation:
Department of Electrical Engineering, Stanford University
E. G. Loh
Affiliation:
Department of Chemical System Engineering, University of Tokyo
Y. Nakano
Affiliation:
Department of Electronic Engineering, University of Tokyo
K. Tada
Affiliation:
Division of Electrical & Computer Engineering, Yokohama National University
H. Komiyama
Affiliation:
Department of Chemical System Engineering, University of Tokyo
Get access

Abstract

Low dielectric constant F-doped silicon oxide films (SiO:F) can be prepared by adding fluorine source, like as CF4 to the conventional PECVD processes. We could obtain SiO:F films with dielectric constant as low as 2.6 from the reaction mixture of SiH4/N2 O/CF4. The structural changes of the oxides were sensitively detected by Raman spectroscopy. The three-fold ring and network structure of the silicon oxides were selectively decreased by adding fluorine into the film. These structural changes contribute to the decrease ionic polarization of the film, but it was not the major factor for the low dielectric constant. The addition of fluorine was very effective to eliminate the Si-OH in the film and the disappearance of the Si-OH was the key factor to obtain low dielectric constant. A kinetic analysis of the process was also performed to investigate the reaction mechanism. We focused on the effect of gas flow rate, i.e. the residence time of the precursors in the reactor, on growth rate and step coverage of SiO:F films. It revealed that there exists two species to form SiO:F films. One is the reactive species which contributes to increase the growth rate and the other one is the less reactive species which contributes to have uniform step coverage. The same approach was made on the PECVD process to produce low-k C:F films from C2F4, and we found ionic species is the main precursor to form C:F films.

Type
Research Article
Copyright
Copyright © Materials Research Society 1999

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1) Ting, Chiu H., Seidel, T.E., Material Research Society Symposium Proceedings, Vol.381, p.3, ed. Lu, T.-M., et al., Material Research Society, San Francisco, CA, April, 1995.Google Scholar
2) Lim, S.W., Shimogaki, Y., Nakano, Y., Tada, K. and Komiyama, H., Appl. Phys. Lett., 68, 832 (1996).10.1063/1.116548Google Scholar
3) Lim, S.W., Shimogaki, Y., Nakano, Y., Tada, K. and Komiyama, H., Jpn. J. Appl. Phys., 35, 1468 (1996).10.1143/JJAP.35.1468Google Scholar
4) Lim, S.W., Shimogaki, Y., Nakano, Y., Tada, K. and Komiyama, H., J. Electrochem. Soc., 144, 2531 (1997).10.1149/1.1837850Google Scholar
5) Yamamoto, K., Tsuji, M., Washino, K., Kasahara, H. and Abe, K., J. Phys. Soc. Jpn., 52, 925 (1983)10.1143/JPSJ.52.925Google Scholar
6) Lucovsky, G., Manitini, M.J., Srivastava, J.K. and Irene, E.A., J. Vac. Sci. Technol. B5 530 (1987).10.1116/1.583944Google Scholar
7) Kittel, C., Introduction to Solid State Physics, 5th ed., p.411, John Wiley & Sons, New York (1976).Google Scholar
8) Shimogaki, Y., Lim, S.W., Nakano, Y., Tada, K. and Komiyama, K., Proc. of 1997 Dielectrics for ULSI Multilevel Interconnection Conference (DUMIC), Santa Clara, CA, p. 189, 1997.Google Scholar
9) Pliskin, W.A., J. Vac. Sci. Technol. 14, 1064 (1977).10.1116/1.569413Google Scholar
10) CRC Handbook of Chemistry and Physics, edited by Lide, D.R. (CRC Press, Boca Raton, 1995) 76th ed., p. 944.Google Scholar
11) Morris, , Viggiano, , et al., J. Phys. Chem., 97, 6208 (1993)10.1021/j100125a020Google Scholar