Hostname: page-component-78c5997874-xbtfd Total loading time: 0 Render date: 2024-11-17T17:21:08.469Z Has data issue: false hasContentIssue false
  • English
  • Français

Absorption and Photoluminescence Study of Cds Quantum Dots: The Role of Host Matrix and Nanocrystal Size and Density

Published online by Cambridge University Press:  10 February 2011

Yu.P. Rakovich ,
A.G. Rolo ,
M.V. Stepikhova ,
M.I. Vasilevskiy ,
M.J.M. Gomes ,
M.V. Artemyev ,
W. Jantsch ,
W. Heiss  and
G. Prechtl
Yu.P. Rakovich
Affiliation:
Departamento de Fisica, Universidade do Minho, 4709-320 Braga, Portugal Department of Physics, Brest Polytechnic Institute, Brest, Belarus
A.G. Rolo
Affiliation:
Departamento de Fisica, Universidade do Minho, 4709-320 Braga, Portugal, E-mail: arolo@a fisica.uminho.pt
M.V. Stepikhova
Affiliation:
Department of Physics, Brest Polytechnic Institute, Brest, Belarus Institute for Physics of Microstructures, RAS, Nizhni Novgorod, Russia
M.I. Vasilevskiy
Affiliation:
Departamento de Fisica, Universidade do Minho, 4709-320 Braga, Portugal
M.J.M. Gomes
Affiliation:
Department of Physics, Brest Polytechnic Institute, Brest, Belarus
M.V. Artemyev
Affiliation:
Physico-Chemical Research Institute, Belarussian State University, Minsk, Belarus
W. Jantsch
Affiliation:
Institute for Semiconductor & Solid State Physics, J. Kepler University, Linz, Austria
W. Heiss
Affiliation:
Institute for Semiconductor & Solid State Physics, J. Kepler University, Linz, Austria
G. Prechtl
Affiliation:
Institute for Semiconductor & Solid State Physics, J. Kepler University, Linz, Austria
Get access

Abstract

In this paper we present results of the absorption and photoluminescence (PL) of CdSdoped Si02 films fabricated by RF co-sputtering (semiconductor volume fraction f=1–15%, nano-crystallite's mean size 5–7nm) and matrix-free films of close-packed CdS nanocrystallites (f∼30%, size 2–5nm) produced by an original chemical method. The absorption spectra have been modelled using the modified Maxwell-Garnett model. This gives the e-h pair state energies and evidence of a strong absorption in the glass matrix containing CdS. The temperature dependence of the spectral position and broadening of the PL peak is analysed. It is concluded that a photo-generated hole is captured on an acceptor-type trap before the radiative recombination with a confined electron. The excitation of this ‘band-edge’ PL occurs through some states in the matrix and directly in the CdS crystallites for the two kinds of samples, respectively. The temperature coefficients of the optical transition energies for the nearly matrix-free films are similar to those of bulk CdS, while for the CdS/glass films they are smaller. This may be because of the different boundary conditions for the thermal expansion of CdS crystallites.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 571: Symposium W – Semiconductor Quantum Dots , 1999 , 69
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. Ekimov, A.I. and Onuzchenko, A.A., Sov. Phys. Semicond. 16, 1215 (1982).Google Scholar
2. Brus, L.E., J. Chem. Phys. 80, 4403 (1984).10.1063/1.447218Google Scholar
3. Klimov, V., Bolivar, P.H. and Kunz, H., Phys. Rev. B 53, 1463 (1996).10.1103/PhysRevB.53.1463Google Scholar
4. Zhao, J. et al. , J. Lumin. 66/67, 332 (1996).10.1016/0022-2313(95)00164-6Google Scholar
5. Rolo, A.G., Conde, O. and Gomes, M.J.M., Thin Solid Films 318, 108 (1998).10.1016/S0040-6090(97)01175-9Google Scholar
6. Kayanuma, Y., Phys. Rev. B 38, 9797 (1988).10.1103/PhysRevB.38.9797Google Scholar
7. Grigorian, G.B., Kazarian, E.M., Efros, Al.L. and Yazeva, T.V., Soy. Phys. Solid State 32, 1772 (1990).Google Scholar
8. Vasilevskiy, M.I., Paula, A.M. de, Akinkina, E.I. and Anda, E.V., Semiconductors 32, 1229 (1998).10.1134/1.1187596Google Scholar
9. Vasilevskiy, M.I. and Anda, E.V., Phys. Rev. B 54, 5844 (1996).10.1103/PhysRevB.54.5844Google Scholar
10. Ramanyah, L.M. and Nair, S.V., Phys. Rev. B 47, 7132 (1993).10.1103/PhysRevB.47.7132Google Scholar
11. Varshni, Y.P., Physica 34, 149 (1967).10.1016/0031-8914(67)90062-6Google Scholar
12. Dmitrenko, V.A., Taranenko, L.V., Shevel', S.R. and Marinchenko, L.V., Fizika I Tekhnika Poluprovodnikov 19, 788 (1985).Google Scholar
13. Eychmuller, A., Hasselbarth, A., Katsitaus, L. and Welter, H., J. Lumin. 48/49, 745 (1991).10.1016/0022-2313(91)90232-KGoogle Scholar
14. Chen, W., Wang, Z.G., Lin, J.L. and Lin, L.Y., Solid State Commun. 101, 371 (1997).10.1016/S0038-1098(96)00530-3Google Scholar
15. Efros, Al.L., Rosen, M., Kuno, M., Nirmal, M., Norris, D.J. and Bawendi, M., Phys. Rev. B 54, 4843 (1996).10.1103/PhysRevB.54.4843Google Scholar
16. Chamarro, M. et al. , Phys. Rev. B 57, 3729 (1998).10.1103/PhysRevB.57.3729Google Scholar