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Defect Reactions Induced by Reactive Ion Etching

Published online by Cambridge University Press:  10 February 2011

Song Zhao
Affiliation:
Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, szhao@photonics.mit.edu
Lionel C. Kimerling
Affiliation:
Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, szhao@photonics.mit.edu
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Abstract

Reactive ion etching (RIE) causes substrate surface contamination, substrate damage, and induces defect reactions to produce carrier traps at depths into μm range. We have developed a model describing the indiffusion of interstitials and the subsequent reactions in the defect reaction region to predict the defect depth profiles. We formulate the reaction kinetics as a series of 1-D coupled interstitial diffusion-reaction partial differential equations (PDEs) with a moving boundary. The predicted defect depth profiles are consistent with those measured in the photoluminescence (PL) experiments. We conclude that the defect depth profiles are determined by interstitial diffusion coefficient (Di), etch rate (υE), etch time (tE), defect reaction rate (K), and background dopant and impurity concentrations ([C], [B] and [O]) in the Si substrate. The μm range defect depth profiles can be explained as: (i) fast diffuser Si self-interstitial (Sii) indiffusion to a μm depth range of (Di/K)1/2 limited by [C] and [B]; (ii) the generation of carbon and boron interstitials (Ci and Bi) through the Watkins replacement reactions, and (iii) the formation of Ci- and Bi-related defect pairs through diffusion limited pairing reactions. Ci and Bi indiffusion are limited by υE and extremely shallow (DiE) during a typical RIE process with υE≈1000Å/min and tE≈10min. The indiffusion of vacancies (V), contamination from the etching plasma and enhanced diffusion effects are also considered in the model.

Type
Research Article
Copyright
Copyright © Materials Research Society 1998

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References

REFERENCES

[1] Chang, C. Y. and Šze, S. M., Chapter 7 in ULSI Technology, (McGraw-Hill, 1996).Google Scholar
[2] Oehrlein, G. S. and Rembetski, J. F., IBM J. R&O, 36, 140 (1992).Google Scholar
[3] Benton, J. L., Michel, J., Kimerling, L. C, Weir, B. E., and Gottscho, R. A., J. Elee. Mater., 20, 643 (1991).Google Scholar
[4] Fonash, S. J., J. Electrochem. Soc, 137, 3885 (1990).Google Scholar
[5] Benton, J. L., Eaglesham, D. J., Gottscho, R. A., Michel, J., Kimerling, L. C, J. Vac. Sci. Tech., BIO, 540 (1992).Google Scholar
[6] Benton, J. L., Kennedy, M. A., Michel, J., Kimerling, L. C, Mater. Sci. Forum, 83–87, 1433 (1992).Google Scholar
[7] Awadelkarim, O. O., Gu, T., Mikulan, P. I., Ditizio, R. A., and Fonash, S. J., Appl. phys. Lett., 62, 958 (1993).Google Scholar
[8] Takeuchi, J., Zaitsu, Y., Shimizu, T., Matsumoto, S., and Wada, K., Mat. Res. Soc. Symp. Proc, 442, 81 (1997).Google Scholar
[9] Nakagawa, O. S., Ashok, S., Kruger, J. K., J. Appl. Phys., 69, 2057 (1991).Google Scholar
[10] Awadelkarim, O. O., Mikulan, P. I., Gu, T., Ditizio, R. A., and Fonash, S. J., IEEE Elec. Dev. Lett., 15, 85 (1994).Google Scholar
[11] Awadelkarim, O.O., Gu, T., Ditizio, R. A., Mikulan, P. I., Fonash, S. J., Rembetski, J. F., and Chan, Y. D., J. Vac. Sci. Tech., A11, 133 (1993).Google Scholar
[12] Henry, A., Monemar, B., Lindström, J. L., Bestwick, T. D., and Oehrlein, G. S., J. Appl. Phys., 70, 5597 (1991).Google Scholar
[13] Buyanova, I. A., Henry, A., Monemar, B., Lindström, J. L., and Oehrlein, G. S., Mater. Sci. Eng. B36, 100 (1996).Google Scholar
[14] Buyanova, I. A., Henry, A., Monemar, B., Lindström, J. L., and Oehrlein, G. S., J. Appl. Phys., 78, 3348 (1995).Google Scholar
[15] Buyanova, I. A., Henry, A., Monemar, B., Lindström, J. L., Sheinkman, M. K., and Oehrlein, G. S., Mater. Sci. Forum 196–201, 1807 (1995).Google Scholar
[16] Kimerling, L. C, Asom, M. T., Benton, J. L., Drevinsky, P. J., and Caefer, C. E., Mater. Sci. Forum, 38–41, 141150 (1989).Google Scholar
[17] Zhao, S., Agarwal, A. M., Benton, J. L., Gilmer, G. H., and Kimerling, L. C., Mater. Res. Soc. Symp. Proc, 442, 231 (1997).Google Scholar
[18] Zhao, S., Chapter 3 in Defect Reactions and Impurity Control in Silicon, Ph.D. Thesis, (Massachusetts Institute of Technology, 1997); to be published.Google Scholar