Hostname: page-component-77c89778f8-7drxs Total loading time: 0 Render date: 2024-07-18T01:15:59.674Z Has data issue: false hasContentIssue false

The Mechanisms of Relaxation in Strained Layer GeSi/Si Superlattices: Diffusion Vs. Dislocation Formation

Published online by Cambridge University Press:  25 February 2011

F. K. LeGoues
Affiliation:
IBM T. J. Watson Research Center, Yorktown Heights, New York 10598, USA
S. S. Iyer
Affiliation:
IBM T. J. Watson Research Center, Yorktown Heights, New York 10598, USA
K. N. Tu
Affiliation:
IBM T. J. Watson Research Center, Yorktown Heights, New York 10598, USA
S. L. Delage
Affiliation:
IBM T. J. Watson Research Center, Yorktown Heights, New York 10598, USA
Get access

Abstract

SixGe1−x strained layer superlattices are known to be metastable in that they can be grown fully commensurate with layer thickness higher than the equilibrium, calculated Tc at which dislocation formation becomes energetically favorable. In this paper, we describe the mechanism of relaxation in such multilayers. Both plane-view and cross-sectional transmission electron microscopy (TEM) were used to examine the formation of dislocation at the different interfaces. RBS was used to follow interdiffusion. We found two competing mechanisms for relaxation: The preferred mode for relaxation is the creation of dislocation networks at each of the interfaces. This process can be stopped or considerably inhibited by the difficulty of forming new dislocations in samples which are perfectly commensurate after growth; Some dislocations appear necessary in order to generate more dislocations during annealing. When this is not the case, the only possible way to attain relaxation is through diffusion. In such a case, stress-enhanced diffusion is observed, with a diffusion coefficient 200 times higher than expected.

Type
Research Article
Copyright
Copyright © Materials Research Society 1988

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

REFERENCES

1.Esaki, L. anf Tsu, R., IBM J. Res. Dev.,14, 61 (1970)Google Scholar
2.Iyer, S. S., Patton, G. L., Delage, S. L., Tiwari, S., and Stork, J. M. C., 2nd Int. Si MBE Conf. Proc., Electrochem. Soc., Hawaii, Oct.1987.Google Scholar
3.van der Merwe, J. H., Surf. Sci, 32, 198 (1972)Google Scholar
4.Kasper, E. and Herzog, H. J., Thin Solid Films, 44, 357 (1977)Google Scholar
5.Bean, J. C., Sheng, T. T., Feldman, L. C., Fiory, H. T. and Lynch, R. T., Appl. Phys. Lett. 44, 102 (1984)Google Scholar
6.Uram, K. J. and Meyerson, B. S., Proceedings of the 1987 Fall Materials Research Society Meeting, Boston, MA Nov. 30- Dec. 4 1987, in press.Google Scholar
7.Fiory, A. T., Bean, J. C., Hull, R. and Nakahara, S., Phys. Rev. B, 31, 4063 (1985)Google Scholar
8.Matthews, J. W. and Blakeslee, A. E., J. of Cryst. Growth, 27, 118 (1974)Google Scholar
9.Matthews, J. W. and Blakeslee, A. E., J. of Cryst. Growth, 29, 273 (1975)Google Scholar
10.Matthews, J. W. and Blakeslee, A. E., J. of Cryst. Growth, 32, 265 (1976)Google Scholar
11.Hagen, W. and Strunk, H., Appl. Physics, 17, 85 (1986)Google Scholar
12.Vdovin, V. I., Matveeva, L. A., Semenova, G. N., Skorohod, N. Y., Tkorik, Y. A. and Khozon, L. S., Phys. Stat. Sol. (a), 92, 379 (1985)Google Scholar
13.Rajan, K. and Denhor, M., J. Appl. Phys. Sept. (1987)Google Scholar
14.Dorner, P., Gust, W., Predel, B., Roll, U., Lodding, A., Odelius, H., Philosophical Magazine, A, vol.49 (1984) 557.Google Scholar