Ruling out the impact of defects on the below band gap photoconductivity of Ti supersaturated Si

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...

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Detalles Bibliográficos
Autores: Martil De La Plaza, Ignacio, García Hemme, Eric, García Hernansanz, Rodrigo, González Díaz, Germán, Olea Ariza, Javier, Prado Millán, Álvaro Del
Tipo de recurso: artículo
Fecha de publicación:2013
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/33561
Acceso en línea:https://hdl.handle.net/20.500.14352/33561
Access Level:acceso abierto
Palabra clave:537
Silicon Solar-Cells
Implanted Silicon
Ion-Implantation
Laser
Semiconductors
Sulfur
Layers.
Electricidad
Electrónica (Física)
2202.03 Electricidad
Descripción
Sumario: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.