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Electronic Structure of Silicide-Silicon Interfaces

Published online by Cambridge University Press:  15 February 2011

G. W. Rubloff  and
P. S. Ho
G. W. Rubloff
Affiliation:
IBM Thomas J. Watson Research Center, Yorktown Heights, NY 10598(U.S.A.)
P. S. Ho
Affiliation:
IBM Thomas J. Watson Research Center, Yorktown Heights, NY 10598(U.S.A.)
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Over the past few years the electronic structure of transition metal-silicon and silicide-silicon interfaces (and of bulk silicide compounds) has been revealed for the first time, using surface spectroscopies (photoemission and Auger) and theoretical calculations. These investigations, which have included palladium, platinum, nickel, vanadium, chromium, molybdenum and tungsten, have elucidated the important role played by the chemical bond between the transition metal d and the Si 3p electrons. They have also shown the high chemical reactivity of the atomically clean transition metal-silicon interface, which leads to interfacial silicide formation at relatively low temperatures (i.e. markedly below those needed for bulk silicide formation on chemically cleaned silicon surfaces). As a result, silicide-like chemical bonding dominates the interface electronic structure of such contacts under a wide variety of conditions. Detailed comparisons of interface spectra (observed at low metal coverages) with those of the bulk silicide reaction products give strong evidence for additional electronic states of relatively high density (about 0.1 states per interface atom) which lie in or near the silicon band gap region. These states are believed to be true interface states associated with localized bonding configurations unique to the atoms at the interface, and they could explain the silicon-rich silicide composition of a thin (about 3–5 Å) interfacial region which has been observed by Auger composition analysis and suggested by chemical shifts in core and valence electron densities of states. Finally, metal atom diffusion into the silicon substrate has been observed in ion channeling studies and suggested from surface spectroscopy results; these impurity atoms should produce defect states localized near the interface and lying within the silicon band gap, although these electronic states have not yet been directly observed. As a whole these results present a fairly detailed picture of the electronic structure and chemistry of the silicide-silicon interface.However, correlations with the interface electrical properties are needed to ascertain which electronic features and chemical mechanisms in fact determine the Schottky barrier height of the contact.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 10: Symposium C – Thin Films and Interfaces I , 1981 , 21
Copyright
Copyright © Materials Research Society 1982

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References

REFERENCES

1 Ho, P. S. and Rubloff, G. W., Thin Solid Films, 89(1982) 433.Google Scholar
2 Tu, K. N. and Mayer, J. W., in Poate, J. M., Tu, K. N. and Mayer, J. W. (eds.), Thin Films—Interdiffusion and Reactions, Wiley, New York, 1978, p. 359.Google Scholar
3 Murarka, S. P., J. Vac. Sci. Technol., 17 (1980) 775.CrossRefGoogle Scholar
4 Crowder, B. L. and Zirinsky, S., IEEE J. Solid-State Circuits, 14 (1979) 291.Google Scholar
5 Sze, S. M., Physics of Semiconductor Devices, Wiley, New York, 1969, p. 410.Google Scholar
6 Ho, P. S., Rubloff, G. W., Lewis, J. E., Moruzzi, V. L. and Williams, A. R., Phys. Rev. B, 22 (1980) 4784.CrossRefGoogle Scholar
7 Freeouf, J. L., Rubloff, G. W., Ho, P. S. and Kuan, T. S., Phys. Rev. Lett., 43 (1979) 1836.Google Scholar
8 Rubloff, G. W., Ho, P. S., Freeouf, J. L. and Lewis, J. E., Phys. Rev. B, 23 (1981) 4183.Google Scholar
9 Miller, J. N., Schwarz, S. A., Lindau, I., Spicer, W. E., deMichelis, B., Abbati, I. and Braicovich, L., J. Vac. Sci. Technol., 17 (1980) 920.Google Scholar
10 Abbati, I., Braicovich, L., deMichelis, B., Bisi, O., Calandra, C., del Pennino, U. and Valeri, S., Proc. 15thInt. Conf. on the Physics of Semiconductors, Kyoto, 1980, Google Scholar
10ain J. Phys. Soc. Jpn. Suppl. A, 49 (1980) 1071.Google Scholar
11 Abbati, I., Rossi, G., Lindau, I. and Spicer, W. E., J. Vac. Sci. Technol., 19 (1981) 636.Google Scholar
12 Pandey, K. C., personal communication, 1980.Google Scholar
13 Bisi, O. and Calandra, C., J. Phys. C, 14 (1981) 5479.Google Scholar
14 Moruzzi, V. L. and Williams, A. R., personal communication.Google Scholar
15 Rubloff, G. W., in Abelès, F. and Croset, M. (eds.), Proc. 8th Int. Vacuum Congr., Cannes, 1980, in Vide, Couches Minces, Suppl., 201 (1980) 562.Google Scholar
16 Rubloff, G. W., Phys. Rev. B, 25 (1982) 4307.Google Scholar
17 Abbati, I., Braicovich, L., DeMichelis, B., Bisi, O. and Rovetta, R., Solid State Commun., 37 (1981) 119.Google Scholar
18 Grunthaner, P. J., Grunthaner, F. J., Madhukar, A. and Mayer, J. W., J. Vac. Sci. Technol., 19 (1981) 649.Google Scholar
19 Riley, J. D., Ley, L., Azoulay, J. and Terakura, K., Phys. Rev. B, 20 (1979) 776.Google Scholar
20 Waclawski, B. J. and Boudreaux, D. S., Solid State Commun., 33 (1980) 589.CrossRefGoogle Scholar
21 Oelhafen, P., Liard, M., Guntherodt, H. J., Berresheim, K. and Polaschegg, H. O., Solid State Commun., 30 (1979) 641.Google Scholar
22 Kelly, M.J. and Bullett, D. W., J. Phys. C, 12 (1979) 2531.Google Scholar
23 Schmid, P. E., Ho, P. S., Föll, H. and Rubloff, G. W., J. Vac. Sci. Technol., 18 (1981) 937.Google Scholar
24 Weaver, J. H., Moruzzi, V. L. and Schmidt, F. A., Phys. Rev. B, 23 (1981) 2916.Google Scholar
25 Clabes, J. G. and Rubloff, G. W., J. Vac. Sci. Technol., 19 (1981) 262.Google Scholar
26 Clabes, J. G., Rubloff, G. W. and Tan, T. Y., to be published.Google Scholar
27 Franciosi, A., Peterman, D. J. and Weaver, J. H., J. Vac. Sci. Technol., 19 (1981) 657.Google Scholar
28 Roth, J. A. and Crowell, C. R., J. Vac. Sci. Technol., 15 (1978) 1317.Google Scholar
29 Freeouf, J. L., Rubloff, G. W., Ho, P. S. and Kuan, T. S., J. Vac. Sci. Technol., 17 (1980) 916.Google Scholar
30 Braicovich, L., Abbati, I., Miller, J. N., Lindau, I., Schwarz, S., Skeath, P. R., Su, C. Y. and Spicer, W. E., J. Vac. Sci. Technol., 17(1980) 1005.CrossRefGoogle Scholar
31 Clabes, J. G., Rubloff, G. W., Reihl, B., Purtell, R. J., Ho, P. S., Zartner, A., Himpsel, F. J. and Eastman, D. E., J. Vac. Sci. Technol., 20 (1982) 684.Google Scholar
32 Purtell, R. J., Clabes, J. G., Rubloff, G. W., Ho, P. S., Reihl, B. and Himpsel, F. J., J. Vac. Sci. Technol., to be published.Google Scholar
33 Himpsel, F. J. and Eastman, D. E., J. Vac. Sci. Technol., 16 (1979) 1297.Google Scholar
34 Ho, P.S., Schmid, P. E. and Föll, H., Phys. Rev. Lett., 46 (1981) 782.Google Scholar
35 Grunthaner, P. J., Grunthaner, F. J. and Mayer, J. W., J. Vac. Sci. Technol., 17 (1980) 924.Google Scholar
36 Cheung, N. W., Grunthaner, P. J., Grunthaner, F. J., Mayer, J. W. and Ullrich, B. M., J. Vac. Sci. Technol., 18 (1981) 917.Google Scholar
37 Freeouf, J. L., Solid State Commun., 33 (1980) 1059.CrossRefGoogle Scholar
38 Freeouf, J. L., J. Vac. Sci. Technol., 18(1981)910.Google Scholar
39 Föll, H., Ho, P.S. and Tu, K. N., J. Appl. Phys., 52(1981) 250;Google Scholar
39aPhilos. Mag., to be published.Google Scholar
40 Ho, P.S., Föll, H., Lewis, J. E. and Schmid, P. E., in Abelès, F. and Croset, M. (eds.), Proc. 4thInt. Conf. on Solid Surfaces, Cannes, 1980, Google Scholar
40a Couches Minces, Suppl., 201 (1980) 1376.Google Scholar
41 Abbati, I., Braicovich, L., DeMichelis, B. and del Pennino, U., J. Vac. Sci. Technol., 17 (1980) 1303.Google Scholar
42 Abbati, I., Braicovich, L., Del Pennino, U. and De Michelis, B., in Abelès, F. and Croset, M. (eds.), Proc. 4thInt. Conf. on Solid Surfaces, Cannes, 1980, in Vide,Google Scholar
42a Couches Minces, Suppl., 201 (1980) 959.Google Scholar
43 Eastman, D. E. and Grobman, W. D., Phys. Rev. Lett., 30 (1973) 177.CrossRefGoogle Scholar
44 Clabes, J. G. and Rubloff, G. W., J. Vac. Sci. Technol., 19 (1981) 262.Google Scholar
45 Ottaviani, G., Tu, K. N. and Mayer, J. W., Phys. Rev. B, 24 (1981) 3354.Google Scholar
46 Schmid, P. E., Ho, P. S. and Tan, T. Y., J. Vac. Sci. Technol., 20 (1982) 688.Google Scholar
47 Cheung, N. W., Culbertson, R. J., Feldman, L. C., Silverman, P. J., West, K. W. and Mayer, J. W., Phys. Rev. Lett., 45 (1980) 120.CrossRefGoogle Scholar
48 Cheung, N. W. and Mayer, J. W., Phys. Rev. Lett., 46 (1981) 671.Google Scholar
49 Himpsel, F. J., Heimann, P., Chiang, T.-C. and Eastman, D. E., Phys. Rev. Lett., 45 (1980) 1112.Google Scholar
50 Freeouf, J. L., Aono, M., Himpsel, F. J. and Eastman, D. E., J. Vac. Sci. Technol., 19 (1981) 681.Google Scholar
51 Iwani, M., Okumo, K., Kamei, S., Ito, T. and Hiraki, A., in Baglin, J. E. and Poate, J. (eds.), Proc. Symp. on Thin Film Interfaces and Interactions, Vol. 80–2, Electrochemical Society, Princeton, NJ, 1980, p. 102.Google Scholar