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A Thermodynamic Model for the Laser Fluence Ablation Threshold of PECVD SiO2 on Thin a-Si:H Films Deposited on Crystalline Silicon

Published online by Cambridge University Press:  01 February 2011

Krister Mangersnes
Affiliation:
kristermangersnes@gmail.com, Institute for Energy Technology, Department of solar energy, Kjeller, Norway
Sean Erik Foss
Affiliation:
sean.erik.foss@ife.no, Institute for Energy Technology, Department of solar energy, Kjeller, Norway
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Abstract

We have developed a thermodynamic model that predicts the heat distribution in a stack of PECVD SiO2 and a-Si:H on crystalline Si after laser irradiation. The model is based on solving the total enthalpy heat equation with a finite difference scheme. The laser used in the model is a frequency doubled Nd:YVO4 green laser with pulse duration in the nanosecond range. The modeling was done with the aim of getting a better understanding of our newly developed laser ablation process for making local contacts on back-junction silicon solar cells. Lasers with pulse duration within the nanosecond range are usually believed to induce too much thermal damage into the underlying silicon to make them suitable for high efficiency solar cells. In our case, insertion of a thin layer of a-Si:H between the SiO2 and the Si absorbs much of the laser irradiation both optically and thermally. This makes it possible to form local contacts to Si in a damage-free way. In addition, the residual a-Si:H serves as an excellent surface passivation layer for the Si substrate. We have also developed a simple static model to determine the onset of SiO2 ablation on a-Si:H layers of varying thickness. The models, both the static and the dynamic, are in good agreement with experimental data.

Type
Research Article
Copyright
Copyright © Materials Research Society 2010

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References

1 Engelhart, P., Harder, N. P., Horstmann, T., Grischke, R., Meyer, R. and Brendel, R., Conference Record of the 2006 IEEE 4th World Conference on Photovoltaic Energy Conversion (IEEE Cat. No. 06CH37747), 4 pp.|CD-ROM (2006).Google Scholar
2 Grohe, A., Harmel, C., Knorz, A., Glunz, S. W., Preu, R., Willeke, G. P., presented at the 4th IEEE World Conference on Photovoltaic Energy Conversion, Vols 1 and 2, 2006.Google Scholar
3 Engelhart, P., Harder, N. P., Grischke, R., Merkle, A., Meyer, R. and Brendel, R., Progress in Photovoltaics 15 (3), 237243 (2007).Google Scholar
4 Engelhart, P., Hermann, S., Neubere, T., Plagwitz, H., Grischke, R., Meyd, R., Klug, U., Schoonderbeek, A., Stute, U. and Brendel, R., Progress in Photovoltaics 15 (6), 521527 (2007).Google Scholar
5 Hermann, S., Neubert, T., Wolpensinger, B., Harder, N.-P. and Brendel, R., presented at the 23rd European Photovoltaic Solar Energy Conference, Valencia, Spain, 2008.Google Scholar
6 Knorz, A., Peters, M., Grohe, A., Harmel, C. and Prett, R., Progress in Photovoltaics 17 (2), 127136 (2009).Google Scholar
7 Mangersnes, K., Foss, S. E. and Thøgersen, A., Journal of Applied Physics 107 (4) (2010).Google Scholar
8 Mangersnes, K. and Foss, S. E., presented at the 24th European PVSEC, Hamburg, Germany, 2009.Google Scholar
9 Aberle, A. G., Progress in Photovoltaics 8 (5), 473487 (2000).Google Scholar
10 Bentzen, A., Ulyashin, A., Sauar, E., Grambole, D., Wright, D. N., Marstein, E. S., Svensson, B. G. and Holt, A., presented at the 15th international Photovoltaic Science and Engineering Conference, Shanghai, China, 2005.Google Scholar
11 Hofmann, M., Schmidt, C., Kohn, N., Rentsch, J., Glunz, S. W. and Preu, R., Progress in Photovoltaics 16 (6), 509518 (2008).Google Scholar
12 Attaf, N., Aida, M. S. and Hadjeris, L., Solid State Communications 120 (12), 525530 (2001).Google Scholar
13 Cahill, D. G., Katiyar, M. and Abelson, J. R., Physical Review B 50 (9), 60776081 (1994).Google Scholar
14 Endo, R. K., Fujihara, Y. and Susa, M., High Temperatures - High Pressures 35–36 (5), 505511 (2003).Google Scholar
15 Grimaldi, M. G., Baeri, P., Malvezzi, M. A. and Sirtori, C., International Journal of Thermophysics 13 (1), 141151 (1992).Google Scholar
16 Kuo, B. S. W., Li, J. C. M. and Schmid, A. W., Applied Physics a-Materials Science & Processing 55 (3), 289296 (1992).Google Scholar
17 Moon, S., Hatano, M., Lee, M. H. and Grigoropoulos, C. P., International Journal of Heat and Mass Transfer 45 (12), 24392447 (2002).Google Scholar
18 Volz, S., Feng, X., Fuentes, C., Guerin, P. and Jaouen, M., International Journal of Thermophysics 23 (6), 16451657 (2002).Google Scholar
19 Wada, H. and Kamijoh, T., Japanese Journal of Applied Physics Part 2-Letters 35 (5B), L648–L650 (1996).Google Scholar
20 Ong, C. K., Tan, H. S. and Sin, E. H., Materials Science and Engineering 79 (1), 7985 (1986).Google Scholar
21 Chen, Y. R., Chang, C. H. and Chao, L. S., Journal of Crystal Growth 303 (1), 199202 (2007).Google Scholar
22 Mariucci, L., Pecora, A., Fortunato, G., Spinella, C. and Bongiorno, C., Thin Solid Films 427 (1–2), 9195 (2003).Google Scholar
23 Yuan, Z., Lou, Q., Zhou, J., Dong, J., Wei, Y., Wang, Z., Zhao, H. and Wu, G., Optics and Laser Technology 41 (4), 380383 (2009).Google Scholar
24 Tosto, S., Applied Physics a-Materials Science & Processing 71 (3), 285297 (2000).Google Scholar
25 Chang, C. H. and Chao, L. S., International Communications in Heat and Mass Transfer 35 (5), 571576 (2008).Google Scholar
26 Matthias, E., Reichling, M., Siegel, J., Kading, O. W., Petzoldt, S., Skurk, H., Bizenberger, P. and Neske, E., Applied Physics a-Materials Science and Processing 58 (2), 129136 (1994).Google Scholar
27 Bauerle, D., Laser Processing and Chemistry, 2 ed. (Springer, 1996).Google Scholar
28 Palik, E. D., Handbook of Optical Constants of Solids. (pp: 571586), Elsevier.Google Scholar
29 Kobatake, H., Fukuyama, H., Minato, I., Tsukada, T. and Awaji, S., Applied Physics Letters 90 (9) (2007).Google Scholar
30 Palankovski, V., Schultheis, R. and Selberherr, S., IEEE Transactions on Electron Devices 48 (6), 12641269 (2001).Google Scholar
31 Jellison, G. E. and Lowndes, D. H., Applied Physics Letters 51 (5), 352354 (1987)Google Scholar