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The Kinetic Energy and Angular Distribution of Sputtered Polyatomic Molecules: Outline and Applications

Published online by Cambridge University Press:  28 February 2011

R. A. Haring*
Affiliation:
IBM Thomas J. Watson Research Center, Yorktown Heights, NY 10598, USA.
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Abstract

Kinetic energy and angular distribution measurements give information about the emission mechanism of desorbed particles. For a sputtering mechanism, the energy and angular distribution is usually assumed to be of the form: Φ(E,θ)∝ E cosθ/(E+U)3 . This expression is valid for sputtered atoms and cannot be immediately applied to the sputtering of molecules, where the energy is shared between internal and external degrees of freedom. A model is presented for the kinetic energy and angular distribution of sputtered polyatomic molecules. The formalism is related to an earlier model for sputtered clusters by Können, Tip and De Vries [1]. It is assumed that the individual atoms of a molecule are given an initial momentum according to linear collision cascade properties. If the molecule does not dissociate, it is treated as an entity and carried as such through a planar surface potential barrier. The model shows a continuous transition from a fragmentation dominated behaviour at high kinetic energies to a collision-cascade-like behaviour at low kinetic energies of the sputtered molecules. The model is compared with experimental data on sputtering of Kr2, SiCl and SiF.

Type
Articles
Copyright
Copyright © Materials Research Society 1987

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References

1. Können, G.P., Tip, A., Vries, A.E. de, Rad. Eff. 26 (1975) 23 (also Rad. Eff. 21 (1974) 269) .CrossRefGoogle Scholar
2. Szymonski, M., Paschke, U., Pedrys, R., Haring, A., Haring, R.A., Roosendaal, H.E., Saris, F.W., Vries, A.E. de, in: Proc. Symposium on Sputtering, ed. Varga, P., Betz, G., Viehböck, F.P. (Technische Universität, Vienna, 1980) 312.Google Scholar
3. Kolfschoten, A.W., Haring, R.A., Haring, A., Vries, A.E. de, J. Appl. Phys. 55 (1984) 3813.CrossRefGoogle Scholar
4. Lin, S.H., Tsong, I.S.T., Ziv, A.R., Szymonski, M., Loxton, C.M., Physica Scripta T9 (1983) 106.CrossRefGoogle Scholar
5. Haring, R.A., Pedrys, R., Haring, A., Vries, A.E. de, Nucl. Instr. Meth. B4 (1984) 40.CrossRefGoogle Scholar
6. Haring, R.A., PhD Thesis, Leiden University and FOM Amsterdam, The Netherlands (1984).Google Scholar
7. Haring, R.A., Roosendaal, H.E., Zalm, P.C., submitted to Nucl. Instr. Meth. B.Google Scholar
8. Sigmund, P., in: Sputtering by particle bombardment vol. I, ed. Behrisch, R. (Springer, Berlin, Heidelberg, New York, 1981).Google Scholar
9. Thompson, M.W., Phil Mag. 18 (1968) 377.CrossRefGoogle Scholar
10. Sigmund, P., Urbassek, H.M., Matragrano, D., Nucl. Instr. Meth. B14 (1986) 495.CrossRefGoogle Scholar
11. Huber, K.P., Herzberg, G., Molecular Spectra and Molecular Structure IV: Constants of Diatomic Molecules (Van Nostrand Reinhold, New York, 1979).CrossRefGoogle Scholar
12. Weast, R.C. (ed.), Handbook of Chemistry and Physics (CRC Press, Inc., Boca Raton, FL, 64th edition, 1983).Google Scholar
13. Haring, R.A., Haring, A., Saris, F.W., Vries, A.E. de, Appl. Phys. Lett. 41 (1982) 174.CrossRefGoogle Scholar
14. Kolfschoten, A.W., private communication.Google Scholar