Hostname: page-component-cd9895bd7-gvvz8 Total loading time: 0 Render date: 2024-12-25T03:22:40.813Z Has data issue: false hasContentIssue false

The Analysis of Berg-Barrett Skew Reflections and their Applications in the Observation of Process-Induced Imperfections in (111) Silicon Wafers

Published online by Cambridge University Press:  06 March 2019

E. M. Juleff
Affiliation:
Westinghouse Space and Defense Center Elkridge, Maryland
A. G. Lapierre III
Affiliation:
Computer Control Company, Inc. Framingham, Massachusetts
R. G. Wolfson
Affiliation:
P. R. Mallory and Company, Inc. Burlington, Massachusetts
Get access

Abstract

The geometry of Berg-Barrett skew reflections (the normal to the specimen surface and the incident and reflected beam vectors are not coplanar) is analyzed with particular reference to (111) silicon. Angular relationships required for obtaining the 78 most intense such reflections are presented on stereographic projections. Skew reflections are utilized to adapt the Berg-Barrett technique of extinction-contrast micrography to the examination of the (111) wafers generally used in integrated circuit technology. Skew reflections are shown to be more suitable for Berg-Barrett micrography than the zero-layer reflections described by Newkirk; in particular, their versatility in providing a means of varying the angle of incidence of the X-ray beam for a specific reflecting plane is demonstrated. A relatively simple experimental arrangement is described for recording skew reflection images. It permits a high resolution X-ray sensitive plate to be placed parallel to the specimen, and their separation to be increased to as much as 5 mm without excessive loss of resolution ; this avoids both image distortion and surface scattering. Furthermore, the specimen area recorded in a single micrograph is 1-3 cm2, which is large enough to eliminate the need for scanning. Exposure times are very short, in the order of 10 min. Micrographs of boron-diffused silicon are presented showing device components delineated by solute strain, strain fields induced in epitaxial silicon films by underlying buried-layer diffusions, and diffusion-induced Lomer-Cottrell dislocations. These micrographs demonstrate the resolution and contrast obtainable over large specimen areas. The capability of the Berg-Barrett technique is discussed in the examination of the near-surface regions directly involved in device fabrication and operation.

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

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

1. Lang, A. R., “Direct Observation of Individual Dislocations,” J. Appl. Phys. 29: 597, 1958.Google Scholar
2. Lang, A. R., “The Project Topograph: A New Method in X-Ray Diffraction Microradiography,” Acta Cryst. 12: 249, 1959.Google Scholar
3. Lang, A. R., “Studies of Individual Dislocations in Crystals by X-Ray Diffraction Microradiography,” J. Appl. Phys. 30: 1748, 1959.Google Scholar
4. Schwuttke, G. H. and Queisser, H. J., “X-Ray Observations of Diffusion-Induced Dislocations in Silicon,” J. Appl. Phys. 33: 1540, 1962.Google Scholar
5. Sctiwuttke, G, H., “X-Ray Observation of Partial Dislocations in Epitaxial Silicon Films,” J. Appl. Phys. 33: 1538, 1962.Google Scholar
6. Schwuttke, G. H. and V. Sils, “X-Ray Analysis of Stacking Fault Structures in Epitaxially Grown Silicon,” J. Appl. Phys. 34: 3127, 1963.Google Scholar
7. Juleff, E. M. and Lapierre, A. G., “The Application of Berg-Barrett Skew Reflections for Observing Boron Diffus ion-Induced Imperfections in Silicon Wafers,” Intern. J. Electron. 20: March, 1966, in press.Google Scholar
8. Newkirk, J. B., “The Observation of Dislocations and Other Imperfections by X-Ray Extinction Contrast,” Trans. AIME 215: 483, 1959.Google Scholar
9. Lauriente, M., Stickler, R., and Armstrong, R. W., “X-Ray Diffraction Analysis and Etch Pattern of Faults in Epitaxial Silicon,” 7. Appl. Phys. 35: 3061, 1964.Google Scholar
10. Meieran, E. S. and Lemons, K. E., “The Study of Defects Due to Surface Processing in Silicon by Means of X-Ray Extinction-Contrast Topography,” Advances in X-Ray Analysis, Vol. 8, Plenum Press, New York, 1964, p. 48.Google Scholar
11. Wolfson, R. G., Juleff, E. M., and Lapierre, A. G., “The Observation of Lomer-Cottrell Dislocations in Boron Diffused (111) Silicon by Berg-Barrett Skew Reflections,” Intern. J. Electron., in review.Google Scholar
12. Miller, D. P., Moore, J. E., and Moore, C. R., “Boron Induced Dislocations in Silicon,” J. Appl. Phys. 33: 2648, 1962.Google Scholar
13. James, R. W., The Optical Principles of the Diffraction of X-Rays, G. Bell and Sons, Ltd., London, 1954, p. 60.Google Scholar