Hostname: page-component-78c5997874-8bhkd Total loading time: 0 Render date: 2024-11-04T21:07:18.975Z Has data issue: false hasContentIssue false

Raman Shift and Broadening in Stress-Minimized Ge Nanocrystals in Silicon Oxide Matrix

Published online by Cambridge University Press:  21 February 2011

YX Jie
Affiliation:
Department of Physics, National University of Singapore, Kent Ridge, Singapore 119260, Singapore.
CHA Huan
Affiliation:
Department of Physics, National University of Singapore, Kent Ridge, Singapore 119260, Singapore.
ATS Wee
Affiliation:
Department of Physics, National University of Singapore, Kent Ridge, Singapore 119260, Singapore.
ZX Shen
Affiliation:
Department of Physics, National University of Singapore, Kent Ridge, Singapore 119260, Singapore.
Get access

Abstract

Ge nanocrystals (nc-Ge) embedded in silicon oxide films were synthesized using RF magnetron sputtering and post-annealing procedure. To minimize the stress effect and inhomogeneity, we intentionally lower the cooling rates and reduce the temperature gradient during annealing. Significant Raman shifts ranging from 2.0 to 5.8 cm−1 have been observed from samples annealed at different temperatures. The size-dependent shift and broadening is found to be in good agreement with the phonon confinement mode together with the Gaussian weighting function, and the isotropic T02 phonon dispersion relation introduced by Sasaki et al. The Raman spectra can also be well-fitted using peaks calculated from the phonon confinement model. The inhomogeneous Raman peak broadening from our samples annealed at lower temperatures are attributed to the non-Gaussian size distribution of Ge nanocrystals.

Type
Research Article
Copyright
Copyright © Materials Research Society 2000

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. Takeoka, S., Fujii, M., Hayashi, S., and Yamamoto, K., Phys. Rev. B, Vol. 58, No. 12, 7921 (1998).Google Scholar
2. Paine, D. C., Caragianis, C., Kim, T. Y., and Shigesato, Y., Appl. Phys. Lett. 62(22), 1993.Google Scholar
3. Zacharias, M. and Fauchet, P. M., Appl. Phys. Lett., 71 (3), 380382, 1997.Google Scholar
4. Zi, J., Zhang, K. and Xie, X., Phys. Rev. B, 55, 9263 (1997).Google Scholar
5. Wu, X. L., Gao, T., Bao, X. M., Yan, F., Jiang, S. S., and Feng, D., J. Appl. Phys. 82(5), 2704(1997).Google Scholar
6. Ma, S. Y., Ma, Z. C., Zong, W. H., Han, H. X., Wang, Z. P., Li, G. H., Qin, G., and Qin, G. G., J. Appl. Phys. 84(1), 559(1998).Google Scholar
7. Guha, S., Wall, M. and Chase, L. L., Nuclear Instruments and Methods in Physics Research B, 147(1999), 367372.Google Scholar
8. Yue, L. P., He, Y. Z., Acta Physica Sinica, 45(10), 1756(1996).Google Scholar
9. Fujii, M., Hayashi, S. and Yamamoto, K., Jap. J. Appl. Phys. 30, 687 (1991).Google Scholar
10. Nilsson, G. and Nelin, G., Phys. Rev. B 15(1971) 364.Google Scholar
11. Maeda, Y., Phys. Rev. B 51(3), 1658(1995).Google Scholar
12.Per Poulsen, R., Wang, M., Xu, J., Li, W., Chen, K., Wang, G., and Feng, D., J. Appl. Phys. Vol. 84, No. 6, 3386 (1998).Google Scholar
13. Campbell, I. H. and Fauchet, P. M., Solid State Commun. 58, 739 (1986).Google Scholar
14. Sasaki, Y. and Horie, C., Phys. Rev. B 47(7), 3811, 1993.Google Scholar
15. Richter, H., Wang, Z. P., and Ley, L., Solid State Commun. 39, 625(1981).Google Scholar
16. Kanata, T., Murai, H., and Kubota, K., J. Appl. Phys. 61(3), 969(1987).Google Scholar
17. Veprek, S., lqbal, Z., and Sarott, E. A., Philos. Mag. B 45, 137 (1982).Google Scholar
18. Tubino, R., Piseri, L., and Zerbi, G., The Journal of Chemical Physics, 56(3), 10221039(1972).Google Scholar
19. Cardona, M., Lighting Scattering in Solids, Edited by Cardona, M. and Guntherodt, G. (Springer, Berlin, 1982), Vol. 2, p. 80.Google Scholar