Hostname: page-component-78c5997874-ndw9j Total loading time: 0 Render date: 2024-11-03T08:14:20.471Z Has data issue: false hasContentIssue false
  • English
  • Français

Structural and Compositional Evolution of Self-Assembled Germanium Islands on Silicon (001) During High Growth Rate LPCVD

Published online by Cambridge University Press:  10 February 2011

Gabriela D.M. Dilliway ,
Nicholas E.B. Cowern ,
Chris Jeynes ,
Lisa O'Reilly ,
Patrick J. McNally  and
Darren M. Bagnall
Gabriela D.M. Dilliway
Affiliation:
Dept. of Electronics and Computer Science, Univ. of Southampton, Highfield, Southampton SO17 1BJ, UK
Nicholas E.B. Cowern
Affiliation:
Advanced Technology Institute, Univ. of Surrey, Guildford GU2 7XH, UK
Chris Jeynes
Affiliation:
Advanced Technology Institute, Univ. of Surrey, Guildford GU2 7XH, UK
Lisa O'Reilly
Affiliation:
Research Institute for Networks & Communications Engineering (RINCE), School of Electronic Engineering, Dublin City University, Dublin 9, Ireland
Patrick J. McNally
Affiliation:
Research Institute for Networks & Communications Engineering (RINCE), School of Electronic Engineering, Dublin City University, Dublin 9, Ireland
Darren M. Bagnall
Affiliation:
Dept. of Electronics and Computer Science, Univ. of Southampton, Highfield, Southampton SO17 1BJ, UK
Get access

Abstract

Understanding the process of self-organization of Ge nanostructures on Si with controlled size distribution is a key requirement for their application to devices. In this study, we investigate the temporal evolution of self-assembled islands during the low pressure chemical vapour deposition (LPCVD) of Ge on Si at 650°C using high growth rates (6–9 nm/min). The islands were characterized by atomic force microscopy, transmission electron microscopy, Rutherford backscattering spectrometry and micro-Raman spectroscopy. We found that the first nanostructures to assemble were small islands, with a narrow size distribution, typical of the ‘lens-shaped’ structures reported in previous studies. Next to form were a population of larger ‘lens-shaped’ islands with a similar surface density to that of the small islands, but with broad height and width distributions. These islands differ from the pyramid-shaped islands previously reported for a similar size range. On further Ge deposition, the population evolves into one of large square-based truncated pyramids with a very narrow size distribution. Such pyramidal structures were previously reported at smaller sizes. Furthermore, we see no evidence of the multifaceted domes previously reported in this size range. The small ‘lens-shaped’ islands appear to be strained, whilst some of the intermediate-sized islands and all the large truncated pyramids contain misfit strain relaxation induced defects. Additionally, in the both the intermediate size ‘lens-shaped’ islands and in the large size truncated pyramidal islands, there is evidence of Si-Ge strain-induced alloying, more significant in the first than in the latter. Our observation of ‘lens shaped’ islands and truncated pyramids at larger sizes than are normally observed, suggests a kinetically driven process that delays the evolution of energetically favourable island structures until larger island sizes are reached.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 775: Symposium P – Self-Assembled Nanostructured Materials , 2003 , P9.25
Copyright
Copyright © Materials Research Society 2003

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

1. Ross, F.M., IBM Res. Develop. 44, 489 (2000).Google Scholar
2. Boscherini, F., Capellini, G., Gaspare, L. di, Rosei, F., Motta, N., Mobilio, S., Appl. Phys. Lett. 76, 682 (2000).Google Scholar
3. Kamins, T.I., Medeiros-Ribeiro, G., Ohlberg, D.A.A., Williams, R. Stanley, Appl. Phys. A 67, 727 (1998).Google Scholar
4. Liao, X.Z., Zou, J., Cockayne, D.J.H., Jiang, Z.M., Wang, X. and Leon, R., Appl. Phys. Lett. 77, 1304 (2000).Google Scholar
5. Loo, R., Meunier-Beillard, P., Vanhaeren, D., Bender, H., Caymax, M., Vandervorst, W., Dentel, D., Goryll, M., Vescan, L., J. Appl. Phys. 90, 2565 (2001).Google Scholar
6. Goryll, M., Vescan, L.,Schmidt, K., Mesters, S., Lüth, H., Appl. Phys. Lett. 71, 410 (1997).Google Scholar
7. Vescan, L., Stoica, T., Chretien, O., Goryll, M., Mateeva, E., Mück, A., J. Appl. Phys. 87, 7275 (2000).Google Scholar
8. Wright, G.B et al., Phys. Rev. Lett., 18, 607 (1967).Google Scholar
9. Kobayashi, T., Endoh, T., Fukuda, H., Noamura, S., Sakai, A., Ueda, Y., Appl. Phys. Lett., 71, 1195 (1997).Google Scholar
10. Wu, X.L., Gao, T., Bao, X.M., Yan, F., Jiang, S.S., Feng, D., J. Appl. Phys., 82, 2704 (1997).Google Scholar
11. Eshed, A., Zhu, J., Yan, J., Beserman, R., Weiss, A.H., Mat. Res. Soc. Symp. Proc., 696, N.3.5.1 (2002).Google Scholar
12. Mooney, P.M., Dacol, F.H., Tsang, J.C. and Chu, J.O., Appl. Phys. Lett., 62, 2069 (1993).Google Scholar