Hostname: page-component-76fb5796d-45l2p Total loading time: 0 Render date: 2024-04-26T22:52:36.568Z Has data issue: false hasContentIssue false

Raman spectroscopy of self-assembled InAs quantum dots in wide-bandgap matrices of AlAs and aluminium oxide

Published online by Cambridge University Press:  11 February 2011

D. A. Tenne
Affiliation:
Institute of Semiconductor Physics, pr. Lavrenteva 13, 630090 Novosibirsk, Russia
A. G. Milekhin
Affiliation:
Institute of Semiconductor Physics, pr. Lavrenteva 13, 630090 Novosibirsk, Russia
A. K. Bakarov
Affiliation:
Institute of Semiconductor Physics, pr. Lavrenteva 13, 630090 Novosibirsk, Russia
O. R. Bajutova
Affiliation:
Institute of Semiconductor Physics, pr. Lavrenteva 13, 630090 Novosibirsk, Russia
V. A. Haisler
Affiliation:
Institute of Semiconductor Physics, pr. Lavrenteva 13, 630090 Novosibirsk, Russia
A. I. Toropov
Affiliation:
Institute of Semiconductor Physics, pr. Lavrenteva 13, 630090 Novosibirsk, Russia
S. Schulze
Affiliation:
Institut für Physik, Technische Universität Chemnitz, D-09107 Chemnitz, Germany
D. R. T. Zahn
Affiliation:
Institut für Physik, Technische Universität Chemnitz, D-09107 Chemnitz, Germany
Get access

Abstract

Vibrational properties of self-assembled InAs quantum dots (QD’s) embedded in AlAs and aluminium oxide were studied by Raman spectroscopy. The InAs/AlAs QD structures were grown by molecular beam epitaxy on GaAs (001) substrates. The following main features of the phonon spectra of InAs/AlAs QD nanostructures were observed: 1) asymmetric lines of QD LO phonons affected by strain, confinement and size inhomogeneity of QD’s; 2) confined phonons of InAs wetting layer (WL); 3) two bands of interface phonons in the AlAs frequency region, attributed to modes associated with the planar interface WL/AlAs matrix and the three-dimensional QD/matrix interface; 4) doublets of folded acoustic phonons caused by periodicity in the multilayer QD structures. The influence of growth temperature, varied from 420 to 550°C, on the morphology of QD’s was investigated. QD’s grown at 420°C are found to have the smallest size. Increasing the temperature up to 480°C leads to the formation of larger InAs islands and improved size homogeneity. Further temperature elevation (above 500°C) causes partial re-evaporation of InAs leading to a decrease of QD size and density, and, finally, their complete disappearance. InAs QD’s embedded in aluminium oxide were fabricated by selective oxidation of the AlAs matrix in self-assembled InAs/AlAs QD’s. Micro-Raman spectroscopy data show that depending on oxidation conditions (humidity, temperature) InAs QD’s in an oxide matrix can be even more strained than before oxidation, or become fully relaxed. At the boundaries of oxidized/non-oxidized areas the presence of amorphous and crystalline As clusters is evident.

Type
Research Article
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

REFERENCES

Bimberg, D., Grundmann, M. and Ledentsov, N. N., Quantum Dot Heterostructures (Wiley, New York, 1999)Google Scholar
Yoffe, D., Adv. Phys. 50 1208 (2001).Google Scholar
3. Polimeni, , Patane, A., Henini, M., Eaves, L., and Main, P. C., Phys Rev B 59, 5064 (1999).Google Scholar
4. Lee, U H, Lee, D, Lee, H G, Noh, S K, Leem, J Y and Lee, H J 1999 Appl Phys Lett 74 1597–99;Google Scholar
Kim, Y S, Lee, U H, Lee, D, Rhee, S J, Leem, Y A, Ko, H S, Kim, D H and Woo, J C 2000 J Appl Phys 87 241244 Google Scholar
5. Pierz, K., Ma, Z., Hapke-Wurst, I., Keyser, U. F., Zeitler, U., and Haug, R. J., Physica E 13, 761 (2002)Google Scholar
6. Dawson, P., Ma, Z., Pierz, K., and Göbel, E. O., Appl. Phys. Lett., 81, 2349 (2001).Google Scholar
7. Dallesasse, J. M., Holonyak, N. Jr, Sugg, A. R., Richard, T. A., and El-Zein, N., Appl Phys Lett 57, 2844 (1990).Google Scholar
8. Richter, H., Wang, Z. P., and Ley, L., Solid State Commun. 39 (1981) 625.Google Scholar
9. Campbell, I. H. and Fauchet, P. M., Solid State Commun. 58 (1986) 739.Google Scholar
10. Grundmann, M., Stier, O. and Bimberg, D., Phys Rev B 52, 11969 (1995).Google Scholar
11. Heitz, R., Veit, M., Ledentsov, N. N., Hoffmann, A., Bimberg, D., Ustinov, V. M., Kop'ev, P. S., and Alferov, Zh. I., Phys Rev B 56, 10435 (1997)Google Scholar
12. Pusep, Yu. A., Zanelatto, G., Da Silva, S. W., Galzerani, J. C., Gonzalez-Borrero, P. P., Toropov, A. I., and Basmaji, P., Phys. Rev. B 58 R1770 (1998).Google Scholar
13. Ballet, P., Smathers, J. B., Yang, H., Workman, C. L., and Salamo, G. J., J. Appl. Phys. 90, 481 (2001);Google Scholar
Ballet, P., Smathers, J. B., and Salamo, G. J., Appl. Phys. Lett. 75, 337 (1999).Google Scholar
14. Knipp, P. A. and Reinecke, T. L., Phys. Rev. B 46, 10310 (1992).Google Scholar
15. Tenne, D. A., Bajutova, O. R., Bakarov, A. K., Kalagin, A. K., Milekhin, A. G., Toropov, A. I., and Zahn, D. R. T., Tech. Phys. Lett 28, 554 (2002).Google Scholar
16. Ashby, C. I. H., Sullivan, J. P., Choquette, K. D., Geib, K. M., and Hou, H. Q., J. Appl. Phys. 82, 3134 (1997).Google Scholar