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Surface Roughness Study of Low-temperature PECVD a-Si:H.

Published online by Cambridge University Press:  01 February 2011

George T. Dalakos,
Joel L. Plawsky and
Peter D. Persans
George T. Dalakos
Affiliation:
General Electric Global Research Center, Niskayuna, NY
Joel L. Plawsky
Affiliation:
Department of Chemical Engineering, Rensselaer Polytechnic Institute, Troy, NY
Peter D. Persans
Affiliation:
Department of Physics, Rensselaer Polytechnic Institute, Troy, NY
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Abstract

Surface topography of a-Si:H thin films, deposited at 75°C by Plasma-enhanced Chemical Vapor Deposition (PECVD) has been examined using helium/silane feedstock mixtures under different substrate bias conditions. Notable differences in the surface roughness evolution are shown for films deposited in “cathodic” versus “anodic” mode – where the substrate is placed on the powered and grounded electrode respectively. Smooth and apparently featureless surfaces result from deposition on RF powered surfaces, upon which a self-bias induces high-energy ion bombardment. Rougher surfaces result from films deposited on electrically grounded surfaces. These anodic films show that after a transition period, surface roughness grows linearly with processing time, exhibiting mounded type growth as evidenced by 2-D power spectral density functions of surface height measurements. Linear growth in roughness has been predicted for shadow growth models assuming film precursor sticking coefficients of one and random angle approach of film precursor species. Growth of this nature has not been reported before in a-Si:H studies, which usually assume directional deposition conditions and sticking coefficients less than unity – occurring even at low processing temperatures.

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References

1. Agarwal, A.M. et al., J. Appl. Phys., 80 (11), 6120, (1996).Google Scholar
2. Sark, W.G.J.H.M. van, in Handbook of Thin Film Materials, edited by Nalwa, H.S. Volume 1: Deposition and Processing of Thin Films, (Academic Press, 2002), pp.1–79.Google Scholar
3. Kondo, M., Fukawa, M., Guo, L., and Matsuda, A., J. Non-Cryst. Solids 266-269, 84 (2000).Google Scholar
4. Dalakos, G.T., Plawsky, J.L., and Persans, P.D., Mat Res. Soc. Symp. Proc., 715, A.19.4. (2002).Google Scholar
5. Kohler, K., Coburn, J.W., Horn, D.E., Kay, E., and Keller, J.H., J. Appl. Phys. 57 (1) 59 (1985).Google Scholar
6. Koh, J., Lu, Y., Wronski, C.R., Kuang, Y., Collins, R.W., Tsong, T.T. and Strausser, Y.E., Appl. Phys. Lett. 69 (9), 1297 (1996).Google Scholar
7. Aue, J. and Hosson, J.Th. M. De, Appl. Phys. Let., 71 (10), 1347 (1997).Google Scholar
8. Tanenbaum, D.M. et al., Phys., Rev. B, 56, 4243 (1997).Google Scholar
9. Flewitt, A.J. et al., J. Appl. Phys., 85, 8032 1999.Google Scholar
10. Kondo, M. et al., J. Non-Cryst. Solids 227-230, 890 (1998).Google Scholar
11. Ikuta, K. et al., Mat. Res. Soc.Symp. Proc. 420, 413 (1996).Google Scholar
12. , Karabacak, Zhao, Y.-P., Wang, G.-C. and Lu, T.-M., Phys. Rev. B, 64, 085323–1, (2001).Google Scholar
13. Smets, A.H.M., Schram, D.C. and Sanden, M.C.M. van de, Mat. Res. Soc. Symp. Proc. 609, A.7.6.1, (2000).Google Scholar
14. Zhao, Y.-P., Wang, G.-C., and Lu, T.-M., Characterization of Amorphous and Crystalline Rough Surfaces: Principles and Applications (Academic Press, San Diego, 2000).Google Scholar
15. Yao, J.H. and Guo, H., Phys. Rev.E 47, 1007 (1993).Google Scholar
16. Cale, T.S. and Mahadev, V., in Modeling of Film Deposition for Microelectronic Applications, Thin Films, Vol 22, ed. Rossnagel, S. and Ulman, A. (Academic Press, San Diego, 1996), p. 192.Google Scholar
17. Perrin, J., Shiratani, M., Kae-Nune, P., Videlot, H., Jolly, J., and Guillon, J., J.Vac. Sci. Tech. A, 16 1, 278 (1998).Google Scholar
18. Ditchfield, R. and Seebauer, E.G., Phys. Rev.B 63, 125317 (2001).Google Scholar