Abstract
Light-induced metastability in hydrogenated nanocrystalline silicon (nc-Si∶:H) single-junction solar cells was studied systematically. First, we observed no light-induced degradation when the photon energy was lower than the band gap of the amorphous phase; degradation occurred when the energy was higher than the band gap in the amorphous phase. The light-induced degradation could be annealed away at an elevated temperature. We concluded that the light-induced defect generation occurred mainly in the amorphous phase. Second, forward current injection did not degrade the nc-Si∶:H cell performance. However, a reverse bias during light soaking enhanced the degradation. Third, the nc-Si∶:H cells made with an optimized hydrogen dilution profile showed minimal degradation although these cells had a high amorphous volume fraction. This indicated that the amorphous volume fraction was not the only factor determining the degradation. Other factors also played important roles in the nc-Si∶:H stability.
Similar content being viewed by others
References
D.L. Staebler and C.R. Wronski: Reversible conductivity changes in discharge-produced amorphous Si. Appl. Phys. Lett. 31, 292 (1977).
J. Meier, R. Flückiger, H. Keppner, and A. Shah: Complete microcrystalline p-i-n solar cell-crystalline or amorphous cell behavior? Appl. Phys. Lett. 65, 860 (1994).
K. Yamamoto: Very thin film crystalline silicon solar cells on glass substrate fabricated at low temperature. IEEE Trans. Electron Dev. 46, 2041 (1999).
S. Klein, F. Finger, R. Carius, T. Dylla, B. Rech, M. Grimm, L. Houben, and M. Stutzmann: Intrinsic microcrystalline silicon prepared by hot-wire chemical vapour deposition for thin film solar cells. Thin Solid Films 430, 202 (2003).
F. Meillaud, E. Vallat-Sauvain, X. Niquille, M. Dubey, J. Bailat, A. Shah, and C. Ballif: Light-induced degradation of thin film amorphous and microcrystalline silicon solar cells, in Proceeding of the 31st IEEE Photovoltaic Specialists Conference, (IEEE, New York, 2005), p. 150.
A. Gordijn, J. Francke, L. Hodakova, J.K. Rath, and R.E.I Schropp: Influence of pressure and plasma potential on high growth rate microcrystalline silicon grown by VHF PECVD, in Amorphous and Nanocrystalline Silicon Science and Technology—2005 edited by R.W. Collins, P.C. Taylor, M. Kondo, R. Carius and R. Biswas (Mater. Res. Soc. Symp. Proc. 862, Warrendale, PA, 2005), p. 87.
H. Fritzsche: Early research on amorphous silicon: Errors and missed opportunities, in Amorphous and Heterogeneous Silicon Thin Films—2000 edited by R.W. Collins, H.M. Branz, M. Stutzmann, S. Guha and H. Okamoto (Mater. Res. Soc. Symp. Proc. 609, Warrendale, PA, 2001), p. A17.1.
H. Branz: Hydrogen diffusion and mobile hydrogen in amorphous silicon. Phys. Rev. B60, 7725 (1999).
D. Williamson (private communication).
B. Yan, G. Yue, J.M. Owens, J. Yang, and S. Guha: Light-induced metastability in hydrogenated nanocrystalline silicon solar cells. Appl. Phys. Lett. 85, 1925 (2004).
G. Yue, B. Yan, J. Yang, and S. Guha: Effect of electrical bias on metastability in hydrogenated nanocrystalline silicon solar cells. Appl. Phys. Lett. 86, 092103 (2005).
G. Yue, B. Yan, J. Yang, and S. Guha: Enhancement of light-induced degradation under reverse bias in hydrogenated nanocrystalline silicon solar cells. J. Appl. Phys. 98, 074902 (2005).
B. Yan, J. Yang, and S. Guha: Effect of hydrogen dilution on the open-circuit voltage of hydrogenated amorphous silicon solar cells. Appl. Phys. Lett. 83, 782 (2003).
B. Yan, J. Yang, and S. Guha: Temperature dependence of dark current-voltage characteristics of hydrogenated amorphous and nanocrystalline silicon based solar cells, in Amorphous and Polycrystalline Thin-Film Silicon Science and Technology—2006, edited by S. Wagner, V. Chu, H.A. Atwater Jr., K. Yamamoto, and H-W. Zan (Mater. Res. Soc. Symp. Proc. 910, Warrendale, PA, 2007), p. A26–02.
L. Yang, L. Chen, J.Y. Hou, and Y.M. Li: The mechanism for defect generation studied by photodegradation of a-Si∶:H solar cells under electrical bias, in Amorphous Silicon Technology—1992, edited by M.J. Thompson, Y. Hamakawa, P.G. LeComber, A. Madan and E. Schiff (Mater. Res. Soc. Symp. Proc. 258, Pittsburgh, PA, 1992), p. 365.
J. Yang, K. Lord, B. Yan, A. Banerjee, and S. Guha: Correlation of the open-circuit voltage enhancement of heterogenous silicon solar cells and the Staebler-Wronski effect, in Proc. 29th IEEE Photovoltaic Specialists Conference (IEEE, New York, 2002), p. 1094.
A. Banerjee, X. Xu, J. Yang, and S. Guha: Carrier collection losses in amorphous silicon and amorphous silicon-germanium alloy solar cells. Appl. Phys. Lett. 67, 2975 (1995).
B. Yan, G. Yue, J. Yang, S. Guha, D.L. Williamson, D. Han, and C. Jiang: Hydrogen dilution profiling for hydrogenated microcrystalline silicon solar cells. Appl. Phys. Lett. 85, 1955 (2004).
A.V. Shah, J. Meier, E. Vallat-Sauvain, N. Wyrsch, U. Kroll, C. Droz, and U. Graf: Material and solar cell research in microcrystalline silicon. Sol. Energy Mater. Sol. Cells. 78, 469 (2003).
E. Vallat-Sauvain, U. Kroll, J. Meier, A. Shah, and J. Pohl: Evolution of the microstructure in microcrystalline silicon prepared by very high frequency glow-discharge using hydrogen dilution. J. Appl. Phys. 87, 3137 (2000).
B. Yan, C.S. Jiang, C.W. Teplin, H.R. Moutinho, M.M. Al-Jassim, J. Yang, and S. Guha: Local current flow in amorphous and nanocrystalline mixed-phase silicon solar cells. J. Appl. Phys. 101, 033711 (2007).
Author information
Authors and Affiliations
Corresponding author
Additional information
Papers in this section are based on submissions to the MRS Symposium Proceedings that were selected by Symposium Organizers as the outstanding paper. Upon selection, authors are invited to submit their research results to Journal of Materials Research. These papers are subject to the same peer review and editorial standards as all other JMR papers. This is another way by which the Materials Research Society recognizes high quality papers presented at its meetings.
This paper was selected as the Outstanding Meeting Paper for the 2006 MRS Spring Meeting Symposium A Proceedings, Vol. 910.
Rights and permissions
About this article
Cite this article
Yue, G., Yan, B., Ganguly, G. et al. Metastability in hydrogenated nanocrystalline silicon solar cells. Journal of Materials Research 22, 1128–1137 (2007). https://doi.org/10.1557/jmr.2007.0144
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1557/jmr.2007.0144