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The Mechanism of Excimer Laser-Induced Amorphization ofUltra-Thin Si Films

Published online by Cambridge University Press:  15 February 2011

T. Eiumchotchawalit  and
James S. Im
T. Eiumchotchawalit
Affiliation:
Columbia University, Department of Chemical Engineering, Materials Science and Mining Engineering, New York, NY
James S. Im
Affiliation:
Columbia University, Department of Chemical Engineering, Materials Science and Mining Engineering, New York, NY
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Abstract

To better understand the involved phase transformation Mechanism, we arestudying the excimer laser-induced amorphization (ELA) of ultra-thin Sifilms on oxidized Si substrates. In this paper, we show that the onset ofamorphization of hydrogen-free Si films on SiO2 substrates uponincreases in the energy density is associated with the onset of completemelting of the film. Once complete melting occurs, further increases in theincident energy density and/or increases in the substrate temperature canlead to incomplete amorphization of the film. Planar view TEM analysis ofnearly-amorphized Si films reveals a heterogeneous microstructure, whichconsists of a mixture of densely dispersed amorphous-like annular regions(∼20 to 40 μm−2), embedded within and typically separated by aregion containing finegrained small crystals. Such a cellular microstructurestrongly suggests that amorphization occurred not via a homogeneous but viaa heterogeneous transformation. In particular, the microstructure paints ascenario in which amorphization proceeded via nucleation of solids, which isthen followed by interfacial amorphization. The experimental resultsunambiguously reveal (1) that the previously proposed criteria of the meltduration and the vertical temperature gradient are irrelevant in determiningamorphization of supercooled liquid Si films and (2) that the quenchingrate, not surprisingly, is the important parameter.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 321: Symposium E – Crystallization and Related Phenomena in Amorphous Materials—Ceramics, Metals, Polymers, and Semiconductors , 1993 , 725
Copyright
Copyright © Materials Research Society 1994

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References

REFERENCES

1. Sameshima, T. and Usui, S., Appl. Phys. Lett. 59 2724 (1991).Google Scholar
2. Sameshima, T. and Usui, S., J. Appl. Phys. 74, 6592 (1993).Google Scholar
3. Dutartre, D., J. Appl. Phys. 59, 1977 (1986).Google Scholar
4. Süffler, S. R., Thompson, M. O., Peercy, P. S., Phys. Rev. Lett. 60, 2519 (1988).Google Scholar
5. Thompson, M. O., Mayer, J. W., Cullis, A. G., Webber, H. C., Chew, N. G., Poate, J. M. and Jacobson, D. C., Phys. Rev. Lett. 50, 896, (1983).Google Scholar
6. Kim, Yeon-Wook, Lin, Hong-Ming and Kelly, T. F., Actametall 37, 247 (1989).Google Scholar
7. Evans, P. V., Devaud, G., Kelly, T. F., and Kim, Yeon-Wook, Actametall 38, 719 (1990).Google Scholar
8. Im, James S., Kim, H. J., and Thompson, M. O., Appl. Phys. Lett. 63, 1969 (1993).Google Scholar
Kim, H. J., Im, James S., and Thompson, M. O., Mat. Res. Soc. Symp. Proc 283, 703 (1993).Google Scholar
9. Gettis, A. and Boots, B., Models of Spatial Processes (Cambridge, UK: Cambridge University Press, 1979).Google Scholar
10. Süffler, S. R., Thompson, M. O., Peercy, P. S., Phys. Rev. B 43, 9851 (1991).Google Scholar
11. Stolk, P. A., Polman, A., and Sinke, W. C., Phys. Rev. B 47, 5 (1993).Google Scholar
12. Turnbull, D., Mat. Res. Soc. Symp. Proc. 51, 71 (1985).Google Scholar
13. Poate, J. M., Mat. Res. Soc. Symp. Proc. 13, 263 (1983).Google Scholar
14. Broughton, J. Q. and Li, X. P., Phys. Rev. B 35, 9120 (1987).Google Scholar