NH_3 Molecular Doping of Silicon Nanowires grown along the [112], [110], [001] and [111] orientations

AbstractThe possibility that an adsorbed molecule could provide shallow electronic states that could be thermally excited has received less attention than substitutional impurities and could potentially have a high impact in the doping of silicon nanowires (SiNWs). We show that molecular-based ex-si...

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Detalles Bibliográficos
Autores: Miranda, Álvaro, Cartoixà, Xavier, Canadell, Enric, Rurali, Riccardo
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2012
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/56408
Acceso en línea:http://dx.doi.org/10.1186/1556-276X-7-308
http://hdl.handle.net/10261/56408
Access Level:acceso abierto
Descripción
Sumario:AbstractThe possibility that an adsorbed molecule could provide shallow electronic states that could be thermally excited has received less attention than substitutional impurities and could potentially have a high impact in the doping of silicon nanowires (SiNWs). We show that molecular-based ex-situ doping, where NH3 is adsorbed at the sidewall of the SiNW, can be an alternative path to n-type doping. By means of first-principle electronic structure calculations, we show that NH3 is a shallow donor regardless of the growth orientation of the SiNWs. Also, we discuss quantum confinement and its relation with the depth of the NH3 doping state, showing that the widening of the bandgap makes the molecular donor level deeper, thus more difficult to activate.