Hostname: page-component-586b7cd67f-rcrh6 Total loading time: 0 Render date: 2024-11-25T17:25:49.266Z Has data issue: false hasContentIssue false

Effect of Implant Energy on Silicon Defect Evolution

Published online by Cambridge University Press:  15 February 2011

J. Desroches
Affiliation:
Dept. of Materials Science and Eng., Univ. of Florida, Gainesville, FL
V. Krishnamoorthy
Affiliation:
Dept. of Materials Science and Eng., Univ. of Florida, Gainesville, FL
K. S. Jones
Affiliation:
Dept. of Materials Science and Eng., Univ. of Florida, Gainesville, FL
C. Jasper
Affiliation:
Semiconductor Products Sector, Motorola Corp., Mesa, AZ
Get access

Abstract

Recent studies on the relationship between defect evolution and transient enhanced diffusion (TED) have lead to the discovery that, for sub-amorphous Si+ implants, atoms released by extended defects (i.e. {311}'s) are a primary source of interstitials for TED. In this paper, the effect of implant energy on the interstitials stored in {311} defects is reported. Silicon wafers were implanted with Si+ at fluences of 1×1014/cm2 and 2×1014/cm2 and energies of 30, 50 and 100 keV. Rapid thermal anneals (RTA) and furnace anneals were performed at times ranging from a few minutes to several hours, at temperatures of 700°, 750° and 800°C. Cross-sectional and plan-view TEM was used to obtain microstructural information. The extended defects observed upon annealing consisted of both {311} defects and dislocation loops. It was found that the ratio of the interstitials bound by extended defects and the implant dose was 0.3. Changing the implant energy did not change the total number of interstitials trapped in both types of defects combined. There was a noticeable variation in the type of defect that dominated each implant regime, despite the constant value of the trapped interstitial to dose ratio. For an RTA of 5 min. at 750°C, the ratio of {311} “rod-like” defects to dislocation loops in the 2×1014/cm2 sample unexpectedly increased as the energy increased from 30 to 50 keV.

Longer furnace anneals were employed to determine the activation energy of {311} dissolution. Our data suggests a slightly higher activation energy for {311} dissolution of approximately 4.2 eV versus the previously reported 3.6 eV, however, this difference may be within experimental error.

Type
Research Article
Copyright
Copyright © Materials Research Society 1997

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 Fahey, P., Barbuscia, G., Moslehi, M., and Dutton, R. W., Kinetics of Thermal Nitridation Processes in the Study of Dopant Diffusion Mechanisms in Silicon, Appl. Phys. Lett. 46, 784 (1985).Google Scholar
2 Fair, R. B., Point defect charge-state effects on transient diffusion of dopants in Si, J. of Electrochem. Soc. 137, 667671 (1990).Google Scholar
3 Jones, K. S., Prussin, S., and Weber, E. R., A Systematic Analysis of Defects in Ion Implanted Silicon, Appl. Phys. A 45, 1 (1988).Google Scholar
4 Giles, M. D., Transient phosphorus diffusion below the amorphization threshold, J. Electrochem. Soc. 138, 11601165 (1991).Google Scholar
5 Eaglesham, D. J., Stolk, P. A., Gossmann, H.-J., and Poate, J. M., Implantation and Transient B Diffusion in Si: The Source of the Interstitials, Appl. Phys. Lett. 65, 23052307 (1994).Google Scholar
6 Eaglesham, D. J., Stolk, P. A., Gossmann, H. J., Haynes, T. E., and Poate, J. M., Implant Damage and Transient Enhanced Diffusion in Si, Nucl. Inst. Meth. B 106, 191 (1995).Google Scholar
7 Servidori, M., Solmi, S., Zaumseil, P., Winter, U., and Anderle, M., Interaction between point defects and dislocation loops as phenomenon able to reduce anomalous diffusion of phosphorus implanted silicon, J. Appl. Phys. 65, 98 (1989).Google Scholar
8 Michel, A. E., Anomalous transient diffusion of ion implanted dopants: a phenomenological model, Nucl. Inst. and Meth. in Phys. Res. B 37/38, 379383 (1989).Google Scholar