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X-Ray Diffraction Contrast from Impurity Precipitates in CdS Single Crystals

Published online by Cambridge University Press:  06 March 2019

Jun-ichi Chikawa*
Affiliation:
NHK Broadcasting Science Research Laboratories 361, Kinuta-machi, Setagaya, Tokyo, Japan
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Abstract

Impurity-doped crystals CdS(GaGl3) have been studied by X-ray topography. Some large precipitates are formed close to the crystal surfaces by annealing at 300°C. In the symmetrical Laue case, the precipitates show circular images (30-60 μ in diameter) due to the radial strains around the precipitates which consist of two semicircles separated by a contrast-free plane parallel to the reflecting plane. The observations indicate that the strain field between the crystal surface and precipitate is not responsible for the contrast, and that the images are formed by X-rays which are deviated from the Bragg condition for the perfect region and satisfy the Bragg condition in the strain field on the inside of the precipitate. One of the semicircles is formed by the incident X-rays with larger glancing angles than the Bragg angle and the other with smaller ones. It is concluded that this contrast is due to the strain around a convex lens shaped precipitate.

Type
Research Article
Copyright
Copyright © International Centre for Diffraction Data 1966

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References

1. Kelly, A. arid Nicholson, R. B., “Precipitation Hardening,” in B. Chalmers (ed.), Progress in Materials Science, Vol. 10, Pergamon Press, Inc., New York, 1963, p. 148.Google Scholar
2. Phillips, V. A. and Livingston, J. D., “Direct Observation of Coherency Strains in a Copper-Cobalt Alloy,” Phil. Mag. 7: 969, 1962.Google Scholar
3. Ashby, M. F. and Brown, L. M., “Diffraction Contrast from Spherically Symmetrical Coherency Strains,” Phil. Mag. 8: 1083, 1649. 1963.Google Scholar
4. Young, F. W. Jr., “The Characterization of Nearly Perfect Copper Crystals,” in: H. S. Peiser (éd.), The Proceedings of the International Conference on Crystal Growth, Pergamon Press, Inc., New York, 1967, p. 789.Google Scholar
5. Authier, A., Malgrange, C., and Fetroff, J. F., “Etude de Defauts Dans le Fluorure de Lithium par la Methode de Lang,” J. Physique 24: 566, 1963.Google Scholar
6. Fairfield, J. M. and Schwuttke, G. H., “Precipitation Effects in Diffused Transistor Structures,” J. Appl. Phys. 37: 1536, 1966.Google Scholar
7. Furusho, K., “Study on Precipitates in Oxygen-Doped Silicon Single Crystals by X-Ray Diffraction Micrography,” J. Appl. Phys. Japan 3: 203, 1964.Google Scholar
8. Chikawa, J., “X-Ray Observation of Clustering of Impurity Atoms in CdS Crystals,” Appl. Phys. Letters 8: 25, 1964.Google Scholar
9. Chikawa, J., “X-Ray Topographic Observation of Dislocation Contrast in Thin CdS Crystals”, J. Appl. Phys. 36: 3496, 1965.Google Scholar
10. Ibuki, S., “On the Crystal Growth of Cadmium Sulfide,” J. Phys. Soc. Japan 14: 1181, 1959.Google Scholar
11. Chikawa, J. and Nakayam, T., “Dislocation Structure and Growth Mechanism of Cadmium Sulfide Crystals,” J. Appl. Phys. 35: 2493, 1964.Google Scholar
12. Lang, A. R., “Studies of Individual Dislocations in Crystals by X-Ray Diffraction Microradiography,” J. Appl. Phys. 30: 1748, 1959.Google Scholar
13. Eshelby, J. D., “The Determination of the Elastic Field of an Ellipsoidal Inclusion, and Related Problems,” Proc. Roy. Soc. 241: 376, 1957.Google Scholar
14. See, for example, Batterman, B. W. and Cole, H., “Dynamical Diffraction of X-Rays by Perfect Crystals,” Rev. Mod. Phys. 36: 681, 1964.Google Scholar
15. Lang, A. R., “X-Ray Topographic Determination of the Sense of Burgers Vectors of Pure Screw Dislocations,” Z. Naturforschg. 20a: 636, 1965.Google Scholar