Hostname: page-component-848d4c4894-wzw2p Total loading time: 0 Render date: 2024-05-20T06:09:08.140Z Has data issue: false hasContentIssue false

A spectroscopic study of optical centers in diamond grown by microwave-assisted chemical vapor deposition

Published online by Cambridge University Press:  31 January 2011

A. T. Collins
Affiliation:
Wheatstone Physics Laboratory, King's College London, Strand, London WC2R 2LS, United Kingdom
M. Kamo
Affiliation:
National Institute for Research in Inorganic Materials, 1-1 Namiki, Tsukuba, Ibaraki 305, Japan
Y. Sato
Affiliation:
National Institute for Research in Inorganic Materials, 1-1 Namiki, Tsukuba, Ibaraki 305, Japan
Get access

Abstract

Absorption and cathodoluminescence spectra have been recorded for single crystals of diamond and polycrystalline films of diamond, grown by microwave-assisted chemical vapor deposition (CVD) using methane and hydrogen. The investigation has been carried out to see to what extent the properties of CVD diamond are similar to those of conventional diamond, and to what extent they are unique. Studies have been made of the as-grown material, which has not been intentionally doped, and also samples that have been subjected to radiation damage and thermal annealing. The single crystals grown using methane concentrations of 0.5 to 1.0% exhibit bright blue “band A” emission and also intense edge emission, similar to the cathodoluminescence spectra of some natural type IIa diamonds. This implies that the crystals are relatively free from structural and chemical defects, a conclusion which is reinforced by the absence of any zero-phonon lines in the absorption spectra of crystals which have been subjected to radiation damage and annealing at 800 °C. Before radiation damage the spectrum does, however, reveal an absorption which increases progressively to higher energies, and which may be associated with sp2-bonded carbon. The Cathodoluminescence spectra after radiation damage indicate that the crystals contain some isolated nitrogen, and the detection of H3 luminescence, following thermal annealing at 800 °C, demonstrates for the first time that these samples contain small concentrations of nitrogen pairs. All of the polycrystalline films, grown using methane concentrations between 0.3 and 1.5%, have an absorption which increases progressively to higher energies, and which again is attributed to sp2-bonded carbon. This absorption is stronger in the films grown using higher methane concentrations. Films grown at a methane concentration of 0.3% also exhibit bright blue cathodoluminescence, although the edge emission is undetectably weak. The use of higher methane concentrations produces films with evidence in the cathodoluminescence spectra of nitrogen + vacancy and nitrogen + interstitial complexes, as well as optical centers unique to CVD diamond. One particular defect produces an emission and absorption line at 1.681 eV. By implanting conventional diamonds with 29Si ions it has been confirmed that this center involves silicon, and it has been shown that the 1.681 eV luminescence is relatively more intense in implanted diamonds which have a high concentration of isolated nitrogen.

Type
Diamond and Diamond-Like Materials
Copyright
Copyright © Materials Research Society 1990

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

1Spitsyn, B.V., Bouilov, L.L., and Deryaguin, B.V., J. Cryst. Growth 52, 219 (1981).Google Scholar
2Matsumoto, S., Sato, Y., Kamo, M., and Setaka, N., Jpn. J. Appl. Phys. 21, L183 (1982).CrossRefGoogle Scholar
3Kamo, M., Sato, Y., Matsumoto, S., and Setaka, N., J. Cryst. Growth 62, 642 (1983).Google Scholar
4De Vries, R. C., Ann. Rev. Mater. Sci. 17, 161 (1987).Google Scholar
5Angus, J. C. and Hayman, C. C., Science 241, 913 (1988).Google Scholar
6Vavilov, V. S., Gippius, A. A., Zaitsev, A. M., Deryaguin, B.V., Spitsyn, B.V., and Aleksenko, A. E., Sov. Phys. Semicond. 14, 1078 (1980).Google Scholar
7Robins, L.H., Cook, L.P., Farabaugh, E.N., and Feldman, A., Phys. Rev. B 39, 13367 (1989).Google Scholar
8Collins, A.T., Kamo, M., and Sato, Y., J. Phys. D 22, 1402 (1989).CrossRefGoogle Scholar
9Yokota, Y., Kawarada, H., and Hiraki, A., in Diamond, Boron Nitride, Silicon Carbide and Related Wide Bandgap Semiconductors, edited by Glass, J.T., Messier, R. F., and Fujimori, N. (Mater. Res. Soc. Symp. Proc. 162, Pittsburgh, PA, 1990).Google Scholar
10Sato, Y. and Kamo, M., Surface and Coatings Technology 39/40, 183 (1989).Google Scholar
11Davies, G., Nature 269, 498 (1977).Google Scholar
12Dean, P. J., Phys. Rev. 139, A588 (1965).Google Scholar
13Yamamato, N., Spence, J. C. H., and Fathy, D., Phil Mag. B 49, 609 (1984).Google Scholar
14Collins, A.T. and Lightowlers, E. C., Properties of Diamond, edited by Field, J. E. (Academic Press, London, 1979), Chap. 3.Google Scholar
15Collins, A.T., Kamo, M., and Sato, Y., J. Phys.: Condensed Matter 1, 4029 (1989).Google Scholar
16Dean, P. J., Lightowlers, E.C., and Wight, D.R., Phys. Rev. 140, A352 (1965).Google Scholar
17Collins, A.T. and Lawson, S. C., J. Phys.: Condensed Matter 1, 6929 (1989).Google Scholar
18Davies, G., Foy, C.M., and O'Donnell, K., J. Phys. C 14, 4153 (1981).Google Scholar
19Davies, G., Chem. Phys. Carbon 13, 1 (1977).Google Scholar
20Collins, A.T., J. Gemm. 18, 37 (1982).Google Scholar