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Development of CdTe on Si Heteroepilayers for Controlled PV Material and Device Studies

  • T.A. Gessert (a1), R. Dhere (a1), D. Kuciauskas (a1), J. Moseley (a1), H. Moutinho (a1), M.J. Romero (a1), M. Al-Jassim (a1), E. Colegrove (a1), R. Kodama (a1) and S. Sivananthan (a1)...


The objective of the National Renewable Energy Laboratory’s (NREL) current three-year CdTe plan under the U.S. Department of Energy’s SunShot Initiative is to identify primary mechanisms that limit the open-circuit voltage and fill factor of polycrystalline CdTe photovoltaic (PV) devices, and develop CdTe synthesis processes and/or device designs that avoid these limitations. Part of this project relies on analysis of crystalline materials and pseudocrystalline CdTe layers where point and extended defects can be introduced sequentially without the complications of extensive impurities and grain boundaries that are typical of present polycrystalline films. The ultimate goals of the project include producing CdTe PV devices that demonstrate ≥20% conversion efficiency, while significantly improving our understanding of processes and materials capable of attaining cost goals of <$0.50 per watt. While NREL is investigating several options for the routine fabrication of high-quality CdTe layers, one pathway involves CdTe molecular beam heteroepitaxy (MBE) on Si in collaboration with the University of Illinois at Chicago. Although CdTe/Si heteroepitaxy is relatively unfamiliar to researchers in the PV community, it has been used successfully for more than 20 years to produce high-quality CdTe surfaces required for commercial production of large-area single-crystal HgCdTe infrared detectors and focal-plane arrays. The process involves chemical and thermal preparation of Si (211) wafers, followed by deposition of As-passivation and ZnTeaccommodation layers. MBE-grown CdTe layers deposited on top of this “template” have been shown to demonstrate low etch-pit density (EPD, preferably ≤ ∼5x105 cm-2) and high structural quality (full width at half maximum ∼ 60 arcs). These initial studies indicate that 10-μm-thick CdTe layers on Si are indeed epitaxial with cathodoluminescence-determined dislocation density consistent with historic EPD measurements, and that recombination rates are distinct from either as-deposited polycrystalline or crystalline materials.


Corresponding author

*University of Illinois at Chicago, Physics Department, Chicago, Illinois 60612
EPIR Technologies, Bolingbrook, Illinois 60440


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1. Green, M.A., Emery, K., Hishikawa, Y., Warta, W., and Dunlop, E.D., “Solar Cell Efficiency Tables (Version 42),” To be published in Prog. Photovolt: Res. Appl. (2013).
2. Nakazawa, T., Takamizawa, K., and Ito, K., “High Efficiency Indium Oxide/Cadmium Telluride Solar Cells,” Appl. Phys. Lett. 50 (5), 279 (1987).
3. Carmody, M., Mallick, S., Margetis, J., Kodama, R., Biegala, T., Xu, D., Bechmann, P., Garland, J.W., and Sivanathan, S., “Single-Crystal II-VI on Si Single-Junction and Tandem Solar Cells,” Appl. Phys. Lett. 96, 153502 (2010).
4. Benson, J.D., Smith, P.J., Jacobs, R.N., Markunas, J.K., Jamie-Vasquez, M., Almeida, L.A., Stoltz, A., Bubulac, L.O., Groenert, M., Wijewarnasuriya, P.A., Brill., G., Chen, Y., and Lee, U., “Topography and Dislocations in (112)B HgCdTe/CdTe/Si,” J. Elect. Mater. 38 (8) 17711775 (2009).
5. Rujirawat, S., Almeida, L.A., Chen, Y.P., Sivananthan, S., and Smith, D.J., “High quality large-area CdTe(211)B on Si(211) grown by molecular beam epitaxy,” Appl. Phys. Lett. 71, 18101812 (1997).
6. Smith, D.J., Tsen, S.C.Y., Chandrasekhar, D., Crozier, P.A., Rujirawat, S., Brill, G., Chen, Y.P., Sporken, R., and Sivananthan, S., “Growth and characterization of CdTe/Si heterostructures - effect of substrate orientation,” Materials Science and Engineering: B 77, 93100 (2000).
7. Kuciauskas, D., Duenow, J.N., Dippo, P., Kanevce, A., Young, M., Li, J.V., Levi, D.H., and Gessert, T.A., “Spectrally and Time Resolved Photoluminescence Analysis of the CdS/CdTe Interface in Thin-Film Photovoltaic Solar Cells,” Submitted to Appl. Phys. Lett. (2013).
8. Benson, J.D., Bubulac, L.O., Smith, P.J., Jacobs, R.N., Markunas, J.K., Jamie-Vasquez, M., Almeida, L.A., Stoltz, A.J., Wijewarnasuriya, P.S., Brill, G., Chen, Y., Lee, U., Vilela, M.F., Peterson, J., Johnson, S.M., Lofgreen, D.D., Rhiger, D., Patten, E.A., and Goetz, P.M., “Characterization of Dislocations in (112)B HgCdTe/CdTe/Si,” J. Elect. Mater. 39 (7) 10801086 (2010).
9. Metzger, W. K., Albin, D., Romero, M. J., Dippo, P., and Young, M., “CdCl2 Treatment, S Diffusion, and Recombination in Polycrystalline CdTe,” Journal of Applied Physics 99, 103703 (2006).
10. Kanevce, A., Kuciauskas, D., Gessert, T., Levi, D.H., and Albin, D., “Impact of Interface Recombination on Time Resolved Photoluminescence (TRPL) Decays in CdTe Solar cells (Numerical Simulation Analysis),” Proc. 38th IEEE Photovoltaic Specialists Conf., Austin, TX (2012).



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