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First-Principles Study of The Etching Reactions of HF and H2O with Si/SiO2 Surfaces

Published online by Cambridge University Press:  21 February 2011

Krishnan Raghavachari ,
G. S. Higashi ,
Y. J. Chabal  and
G. W. Trucks
Krishnan Raghavachari
Affiliation:
AT&T Bell Laboratories, Murray Hill, NJ 07974
G. S. Higashi
Affiliation:
AT&T Bell Laboratories, Murray Hill, NJ 07974
Y. J. Chabal
Affiliation:
AT&T Bell Laboratories, Murray Hill, NJ 07974
G. W. Trucks
Affiliation:
Lorentzian, Inc., 140 Washington Avenue, North Haven, CT 06473
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Abstract

First-principles quantum chemical techniques are used to unravel the mechanism leading to hydrogen-terminated silicon surfaces upon etching. Our calculations on model compounds indicate that kinetic rather than thermodynamic considerations are responsible for the H-passivation. In the etching reactions of HF, the initial oxide removal leads to Ftermination of the surface dangling bonds. Subsequent HF attack of the Si–Si back-bonds then leads to the final H-terminated surface. The principal driving force is the ionic nature of the Si–F bond which polarizes the Si–Si back-bonds. This polarization facilitates reactions with HF resulting in efficient removal of fluorine-bonded surface silicon as SiF4 leaving behind hydrogen. Analogous etching reactions of water involve larger barriers and can only be seen at elevated temperatures.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 315: Symposium Y – Surface Chemical Cleaning and Passivation for Semiconductor Processing , 1993 , 437
Copyright
Copyright © Materials Research Society 1993

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References

REFERENCES

[1] Kern, W., J. Electrochem. Soc. 137, 1887 (1990).CrossRefGoogle Scholar
[2] Buck, T. and McKim, F.S., J. Electrochem. Soc. 105, 709 (1958).CrossRefGoogle Scholar
[3] For a recent review, see: Higashi, G.S. and Chabal, Y.J., in Handbook of Semiconductor Cleaning Technology, Kern, W., Ed. (1993).Google Scholar
[4] Raider, S. I., Flitsch, R., and Palmer, M.J., J. ELectrochem. Soc. 122, 413 (1975).CrossRefGoogle Scholar
[5] Weinberger, B.R., Peterson, G.G., Eschrich, T.C., and Krasinski, H.A., J. Appl. Phys. 60, 3232 (1986).CrossRefGoogle Scholar
[6] Ubara, H., Imura, T., and Hiraki, A., Solid State Comm. 50, 673 (1984).CrossRefGoogle Scholar
[7] Yablonovitch, E., Allara, D.L., Chang, C.C., Gmitter, T., and Bright, T.B., Phys. Rev. Lett. 57, 249 (1986).CrossRefGoogle Scholar
[8] Grundner, M. and Jacob, J., Appl. Phys. A39, 73 (1986).CrossRefGoogle Scholar
[9] Burrows, V.A., Chabal, Y.J., Higashi, G.S., Raghavachari, K. and Christman, S.B., Appl. Phys. Lett. 53, 998 (1988).CrossRefGoogle Scholar
[10] Chabal, Y.J., Higashi, G.S., Raghavachari, K. and Burrows, V.A., J. Vac. Sci. Technol. A7, 2104 (1988).Google Scholar
[11] Dumas, P. and Chabal, Y. J., Chem. Phys. Lett. 181, 537 (1991).CrossRefGoogle Scholar
[12] Higashi, G.S., Chabal, Y.J., Trucks, G.W., and Raghavachari, K., Appl. Phys. Lett. 56, 656 (1990).CrossRefGoogle Scholar
[13] Jakob, P. and Chabal, Y.J., J. Chem. Phys. 95, 2897 (1991).CrossRefGoogle Scholar
[14] Watanabe, S., Nakayama, N., and Ito, T., Appl. Phys. Lett. 59, 1458 (1991).CrossRefGoogle Scholar
[15] Morita, M., Ohmi, T., Hasegawa, E., Kawakami, M., and Suma, K., Appl. Phys. Lett. 55, 562 (1989).CrossRefGoogle Scholar
[16] Pietsch, G.J., Köhler, U., and Henzler, M., Chem. Phys. Lett. 197, 346 (1992).CrossRefGoogle Scholar
[17] Trucks, G.W., Raghavachari, K., Higashi, G.S., and Chabal, Y.J., Phys. Rev. Lett. 65, 504 (1990).CrossRefGoogle Scholar
[18] For information on basis sets and correlation methods used in this study, see Hehre, W.J., Radom, L., Schleyer, P.v.R., and Pople, J.A., Ab Initio Molecular Orbital Theory (J. Wiley, New York, 1986).Google Scholar
[19] Hariharan, P.C. and Pople, J.A., Chem. Phys. Lett. 66, 217 (1972). M.M. Francl, W.J. Pietro, W.J. Hehre, J.S. Binkley, M.S. Gordon, D.J. DeFrees and J.A. Pople, J. Chem. Phys. 77, 3654 (1982).CrossRefGoogle Scholar
[20] Møler, C. and Plesset, M.S., Phys. Rev. 46, 618 (1934). 446CrossRefGoogle Scholar
[21] Binkley, J.S. and Pople, J.A., Int. J. Quant. Chem. 9, 229 (1975).CrossRefGoogle Scholar
[22] Pople, J.A., Krishnan, R., Schlegel, H.B. and Binkley, J.S., Int. J. Quant. Chem. Symp. 13, 255 (1979).Google Scholar
[23] Pople, J.A., Head-Gordon, M. and Raghavachari, K., J. Chem. Phys. 87, 5968 (1987).CrossRefGoogle Scholar
[24] Krishnan, R., Binkley, J.S., Seeger, R. and Pople, J.A., J. Chem. Phys. 72, 650 (1980).CrossRefGoogle Scholar
[25] McLean, A.D. and Chandler, G.S., J. Chem. Phys. 72, 5639 (1980).CrossRefGoogle Scholar
[26] Judge, J.S., J. Electrochem. Soc. 118, 1772 (1971).CrossRefGoogle Scholar
[27] Pattern etching in vapors from aqueous HF yields comparable results to liquid etching at reasonable etch rates, see Holmes, P.J. and Snell, J.E., Microelec. and Reliab. 5, 337 (1966).CrossRefGoogle Scholar
[28] Novak, R.E., Solid State Technol. (March 1988) p 39.Google Scholar
[29] Garrison, B.J. and Goddard, W.A. III, Phys. Rev. B36,9805 (1987).CrossRefGoogle Scholar
[30] Walle, C.G. Van de, McFreely, F.R., and Pantelides, S.T., Phys. Rev. Lett. 61, 1867 (1988).CrossRefGoogle Scholar
[31] McFeely, F.R., Morar, J.F., and Himpsel, F.J., Surf. Sci. 165, 277 (1986).CrossRefGoogle Scholar
[32] Hu, S.M. and Kerr, D.R., J. Electrochem. Soc. 114, 414 (1967).CrossRefGoogle Scholar