RT Journal Article T1 Ruling out the impact of defects on the below band gap photoconductivity of Ti supersaturated Si A1 Martil De La Plaza, Ignacio A1 García Hemme, Eric A1 García Hernansanz, Rodrigo A1 González Díaz, Germán A1 Olea Ariza, Javier A1 Prado Millán, Álvaro Del AB In this study, we present a structural and optoelectronic characterization of high dose Ti implanted Si subsequently pulsed-laser melted (Ti supersaturated Si). Time-of-flight secondary ion mass spectrometry analysis reveals that the theoretical Mott limit has been surpassed after the laser process and transmission electron microscopy images show a good lattice reconstruction. Optical characterization shows strong sub-band gap absorption related to the high Ti concentration. Photoconductivity measurements show that Ti supersaturated Si presents spectral response orders of magnitude higher than unimplanted Si at energies below the band gap. We conclude that the observed below band gap photoconductivity cannot be attributed to structural defects produced by the fabrication processes and suggest that both absorption coefficient of the new material and lifetime of photoexcited carriers have been enhanced due to the presence of a high Ti concentration. This remarkable result proves that Ti supersaturated Si is a promising material for both infrared detectors and high efficiency photovoltaic devices. PB American Institute of Physics SN 0021-8979 YR 2013 FD 2013-08-07 LK https://hdl.handle.net/20.500.14352/33561 UL https://hdl.handle.net/20.500.14352/33561 LA eng NO 1) A. Martí and A. Luque, Next Generation Photovoltaics: High Efficiency Through Full Spectrum Utilization (IOP Publishing, Ltd., Bristol, 2004).2) G. Conibeer, Mater. Today 10, 42 (2007).3) A. Luque and A. Martí, Phys. Rev. Lett. 78, 5014 (1997).4) M. Casalino, Int. J. Opt. Appl. 2, 1 (2012).5) A. Luque, A. Martí, E. Antolín, and C. 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NO © 2013 AIP Publishing LLC. he authors would like to acknowledge the C.A.I. de Técnicas Físicas for ion implantation experiments and e-beam evaporations, the Nanotechnology and Surface Analysis Services of the Universidad de Vigo C.A.C.T.I. for ToF-SIMS measurements, Dr. J. Herrero (CIEMAT) for UVVIS-IR measurements facilities, and the Instituto de Nanociencia de Aragón for the TEM images. 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 this research was undertaken. Research by E. Garcìa-Hemme has been partly supported by a PICATA predoctoral fellowship of the Moncloa Campus of International Excellence (UCM-UPM). This work was partially supported by the projects NUMANCIA II (S-2009/ENE-1477) founded by the Regional Government of Comunidad de Madrid and grant GR35/10-A founded by the Universidad Complutense de Madrid. NO Comunidad de Madrid NO MICINN DS Docta Complutense RD 1 sept 2024