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Visible and infra-red light emission in boron-doped wurtzite silicon nanowires.

ABSTRACT: Silicon, the mainstay semiconductor in microelectronic circuitry, is considered unsuitable for optoelectronic applications owing to its indirect electronic band gap, which limits its efficiency as a light emitter. Here we show the light emission properties of boron-doped wurtzite silicon nanowires measured by cathodoluminescence spectroscopy at room temperature. A visible emission, peaked above 1.5 eV, and a near infra-red emission at 0.8 eV correlate respectively to the direct transition at the ? point and to the indirect band-gap of wurtzite silicon. We find additional intense emissions due to boron intra-gap states in the short wavelength infra-red range. We present the evolution of the light emission properties as function of the boron doping concentration and the growth temperature.

SUBMITTER: Fabbri F

PROVIDER: S-EPMC3884225 | biostudies-other | 2014

REPOSITORIES: biostudies-other

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Visible and infra-red light emission in boron-doped wurtzite silicon nanowires.

Fabbri Filippo F Rotunno Enzo E Lazzarini Laura L Fukata Naoki N Salviati Giancarlo G

Scientific reports 20140108

Silicon, the mainstay semiconductor in microelectronic circuitry, is considered unsuitable for optoelectronic applications owing to its indirect electronic band gap, which limits its efficiency as a light emitter. Here we show the light emission properties of boron-doped wurtzite silicon nanowires measured by cathodoluminescence spectroscopy at room temperature. A visible emission, peaked above 1.5 eV, and a near infra-red emission at 0.8 eV correlate respectively to the direct transition at the ...[more]

PMID: 24398782

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