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Mechanical Properties and Adhesion of CdTe/CdS Thin Film Solar Cells Deposited on Flexible Foil Substrates

  • Deidra Ranel Hodges (a1), Vasilios Palekis (a2), Shweta Bhandaru (a3), Kartikay Singh (a4), Don L Morel (a5) and Lee Stefanakos (a6)...

Abstract

Cadmium telluride (CdTe) is a leading thin film photovoltaic (PV) material due to its near ideal band gap of 1.45 eV, its high optical absorption coefficient and availability of various device fabrication methods. Superstrate CdTe solar cells fabricated on glass have to-date exhibited efficiencies of 16.5%. Work on substrate devices has been limited due to difficulties associated with the formation of an ohmic contact with CdTe. Foil substrate curvature, flaking, delamination and adhesion as a result of compressive strain due to the coefficient of thermal expansion (CTE) mismatch between the flexible foil substrate and the solar cell films has been studied. Thin films have been characterized by AFM, XRD, SEM, ASTM D3359-08 tape test, and solar cells have been characterized using J-V and spectral measurements. Adhesion improves by minimizing the mismatch of the CTE . A CdCl2 treatment is important for high efficiency solar cells. The treatment influences the microstructure and interface properties of the layers. The effect of the current CdCl2 chemical treatment increases flaking and has to be optimized for the CdTe substrate cell on foil. We have also fabricated solar cells on tantalum, molybdenum and tungsten foils, all with lower CTEs than SS430. We are currently producing solar cells with a VOC of 630mV, a 50% fill factor and over 6.0% efficiency.

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References

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1. Singh, V.P. McClure, J.C.Design issues in the fabrication of CdS-CdTe solar cells on molybdenum foil substrates”, Solar Energy Materials & Solar Cells, 76, (2003), 369385.
2. McMahon, T.J. Jorgensen, G.J. “Adhesion and Thin-Film Module Reliability”, National Renewable Energy Laboratory, IEEE, 2006.
3. Ferekides, C.S. Viswanathan, V. Morel, D.L. “RF Sputtered Back Contacts for CdTe/CdS Thin Film Solar Cells”, 26th IEEE PVSC, (1997).
4. Romeo, N. Bosio, A. Tedeschi, R. Canevari, V.Back Contacts to CSS CdS/CdTe Solar Cells and Stability of Performances”, Thin Solid Films, 361-362, (2000), 327329.
5. Kessler, F. Rudmann, D.Technological aspects of flexible CIGS solar cells and modules”, Solar Energy Materials & Solar Cells, 77, (2004), 685695.
6. Vink, T.J. Somers, M.A. Daams, J.L.C. Dirks, A.G.Stress, strain, and microstructure of sputter-deposited Mo thin films”, J. Appl. Phys., 70, (8), 1991.
7. Al-Thani, H.A., Hasson, F.S. Alleman, J.L. and Al-Jassim, M.M., “The Deposition and Characterization of Mo/CuInGaSe2/CdS/ZnO Solar Cells”, presented at the Sharjah Solar Energy Conference, February, 2001, Sharaj, UAE; available electronically at: http://www.doe.gov.bridge

Keywords

Mechanical Properties and Adhesion of CdTe/CdS Thin Film Solar Cells Deposited on Flexible Foil Substrates

  • Deidra Ranel Hodges (a1), Vasilios Palekis (a2), Shweta Bhandaru (a3), Kartikay Singh (a4), Don L Morel (a5) and Lee Stefanakos (a6)...

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