Hostname: page-component-78c5997874-94fs2 Total loading time: 0 Render date: 2024-11-02T23:26:45.394Z Has data issue: false hasContentIssue false

Luminescence and EPR Study of Lithium-Diffused ZnO Crystals

Published online by Cambridge University Press:  11 February 2011

N. Y. Garces
Affiliation:
Physics Department, West Virginia University, Morgantown, WV 26506–6315, U.S.A.
Lijun Wang
Affiliation:
Physics Department, West Virginia University, Morgantown, WV 26506–6315, U.S.A.
M. M. Chirila
Affiliation:
Physics Department, West Virginia University, Morgantown, WV 26506–6315, U.S.A.
L. E. Halliburton
Affiliation:
Physics Department, West Virginia University, Morgantown, WV 26506–6315, U.S.A.
N. C. Giles
Affiliation:
Physics Department, West Virginia University, Morgantown, WV 26506–6315, U.S.A.
Get access

Abstract

Zinc oxide (ZnO) crystals grown by the seeded chemical vapor transport method have been studied using photoluminescence (PL), thermoluminescence (TL), and electron paramagnetic resonance (EPR) techniques. Lithium acceptors were diffused into the crystals during anneals in LiF powder at temperatures in the 750 to 850°C range. After a lithium diffusion, EPR was used to monitor neutral lithium acceptors and neutral shallow donors, as well as Ni3+, Fe3+, and Cu2+ impurities unintentionally present. Excitonic and deep-level PL emissions were also monitored before and after these diffusions. Two broad overlapping TL emission bands were observed at 117 and 145 K when a Li-diffused crystal was illuminated at 77 K with 325-nm light and then rapidly warmed to room temperature. The two TL bands have the same spectral dependence (the peak in wavelength is 540 nm when the intensity of the light reaches a maximum). These “glow” peaks occur when electrons are thermally released from Ni2+ and Fe2+ ions and recombine with holes at neutral lithium acceptors.

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

1. Look, D. C., Mater. Sci. Eng. B 80, 383 (2001).Google Scholar
2. Schirmer, O. F., J. Phys. Chem. Solids 29, 1407 (1968).Google Scholar
3. Look, D. C., Reynolds, D. C., Garces, N. Y., Giles, N. C., and Halliburton, L. E., Phys. Stat. Sol. (a) 195, (to appear in January, 2003 issue).Google Scholar
4. Tomzig, E. and Helbig, R., J. Luminescence 14, 403 (1976).Google Scholar
5. Dingle, R., Phys. Rev. Lett. 23, 579 (1969).Google Scholar
6. Schirmer, O. F. and Zwingel, D., Solid State Commun. 8, 1559 (1970).Google Scholar
7. Zwingel, D., J. Luminescence 5, 385 (1972).Google Scholar
8. Cox, R. T., Block, D., Herve, A., Picard, R., Santier, C., and Helbig, R., Solid State Commun. 25, 77 (1978).Google Scholar
9. Heitz, R., Hoffmann, A., and Broser, I., Phys. Rev. B 45, 8977 (1992).Google Scholar
10. Holton, W. C., Schneider, J., and Estle, T. L., Phys. Rev. 133, A1638 (1964).Google Scholar
11. Walsh, W. M. and Rupp, L. W., Phys. Rev. 126, 952 (1962).Google Scholar
12. Igelmund, A. and Hausmann, A., Z. Physik B 21, 65 (1975).Google Scholar
13. Dietz, R. E., Kanimura, H., Sturge, M. D., and Yariv, A., Phys. Rev. 132, 1559 (1963).Google Scholar