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Hydrogenated amorphous silicon deposited by high pressure sputtering for HIT solar cells

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Hydrogenated amorphous silicon thin films were deposited using a high pressure sputtering (HPS) system. In this work, we have studied the composition and optical properties of the films (band-gap, absorption coefficient), and their dependence with the deposition parameters. For films deposited at high pressure (1 mbar), composition measurements show a critical dependence of the purity of the films with the RF power. Films manufactured with RF-power above 80W exhibit good properties for future application, similar to the films deposited by CVD (Chemical Vapor Deposition) for hydrogenated amorphous silicon.
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Spanish Conference on Electron Devices (CDE) (9.2013.Valladolid.España). Authors would like to acknowledge C.A.I. de Técnicas Físicas and C.A.I de Espectroscopía of the Universidad Complutense de Madrid for the use of its laboratories and FTIR measurements. Also we would like to acknowledge Unidad de Energía Solar Fotovoltáica of CIEMAT, for allowing us to measure transmittance and reflectance. This work was partially supported by the Project NUMANCIA II (Grant No. S-2009/ENE/1477) funded by the Comunidad de Madrid. Research by Eric Garcia-Hemme was partially supported by a PICATA predoctoral fellowship of the Moncloa Campus of International Excellence (UCM-UPM). J. Olea and D. Pastor thanks Professor A. Martí and Professor A. Luque for useful discussions and guidance and acknowledge financial support from the MICINN within the program Juan de la Cierva (JCI-2011-10402 and JCI-2011-11471), under which their research was undertaken.
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[1] Y. Tsunomura, Y. Yoshimine, M. Taguchi, T. Baba, T. Kinoshita, H. Kanno, et al., "Twenty-two percent efficiency HIT solar cell," Solar Energy Materials and Solar Cells, vol. 93, pp. 670-673, Jun 2009. [2] F. Roca, J. Cárabe, and A. Jäger-Waldau, "Silicon Heterojunction cells R&D in Europe," in 19th EU-PVSEC, 2004. [3] A. Luque and A. Martí, "Increasing the efficiency of ideal solar cells by photon induced transitions at intermediate levels," Physical Review Letters, vol. 78, pp. 5014-5017, Jun 30 1997. [4] E. García-Hemme, R. García-Hernansanz, J. Olea, D. Pastor, Á. del Prado, I. Mártil, et al., "Sub-bandgap spectral photo-response analysis of Ti supersaturated Si," Applied Physics Letters, vol. 101, 5 Nov. 2012. [5] J. Olea, Á. del Prado, D. Pastor, I. Mártil, and G. González-Díaz, "Sub-bandgap absorption in Ti implanted Si over the Mott limit," Journal of Applied Physics, vol. 109, Jun 1 2011. [6] E. García-Hemme, R. García-Hernansanz, J. Olea, D. Pastor, Á. del Prado, I. Mártil, et al., "Ion implantation and pulsed laser melting processing for the development of an intermediate band material," AIP Conference Proceedings, vol. 1496, 2012 2012. [7] P. C. Feijoo, Á. del Prado, M. Toledano-Luque, E. San Andrés, and M. L. Lucía, "Scandium oxide deposited by high-pressure sputtering for memory devices: Physical and interfacial properties," Journal of Applied Physics, vol. 107, Apr 15 2010. [8] J. L. Hernández-Rojas, M. L. Lucía, I. Mártil, G. González-Díaz, J. Santamaría,and F. Sánchez-Quesada, "Optical analysis of absorbing thin-films application to ternary chalcopyrite semiconductors" Applied Optics, vol. 31, pp. 1606,Apr 1 1992. [9] R. W. B. Pearse and A. G. Gaydon, The identification of Molecular Spectra, 4 ed. London, 1976. [10] A. H. Mahan, L. M. Gedvilas, and J. D. Webb, "Si-H bonding in low hydrogen content amorphous silicon films as probed by infrared spectroscopy and x-ray diffraction," Journal of Applied Physics, vol. 87, Feb 15 2000. [11] Y. Rong-Hwei, Y. Tai-Rong, C. Te-Cheng, L. Shih-Yung, and H. Jyh-Wong, "Optoelectronic characteristics of direct-current and alternating-current white thin-film light-emitting diodes based on hydrogenated amorphous silicon nitride film," IEEE Transactions on Electron Devices, vol. 55, April 2008. [12] A. A. Langford, M. L. Fleet, B. P. Nelson, W. A. Lanford, and N. Maley, "infrared-absorption strength and hydrogen content of hydrogenated amorphous-silicon," Physical Review B, vol. 45, Jun 15 1992. [13] J. Tauc, Grigorov.R, and A. Vancu, "optical properties and electronic structure of amorphous germanium," Physica Status Solidi, vol. 15, 1966 1966. [14] G. D. Cody, B. G. Brooks, and B. Abeles, "optical-absorption above the optical gap of amorphous-silicon hydride," Solar Energy Materials, vol. 8, 1982 1982. [15] R. C. Ross and R. Messier, "microstructure and properties of RFsputtered amorphous hydrogenated silicon films," Journal of Applied Physics, vol. 52, 1981 1981.