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.
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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