Recombination Dynamics of Spatially Confined Electron-Hole System in Luminescent Gold Catalyzed Silicon Nanowires

Laboratoire Silicium Nanoelectronique Photonique et Structure, Service de Physique des Materiaux et Microstructures, Institut Nanosciences et Cryogenie, Commissariat a l'Energie Atomique, F-38054 Grenoble Cedex, France. .
Nano Letters (Impact Factor: 13.59). 08/2009; 9(7):2575-8. DOI: 10.1021/nl900739a
Source: PubMed

ABSTRACT

We study by time-resolved low temperature photoluminescence (PL) experiments of the electronic states of silicon nanowires (SiNWs) grown by gold catalyzed chemical vapor deposition and passivated by thermal SiO(2). The typical recombination line of free carriers in gold-catalyzed SiNWs (Au-SiNWs) is identified and studied by time-resolved experiments. We demonstrate that intrinsic Auger recombination governs the recombination dynamic of the dense e-h plasma generated inside the NW. In a few tens of nanoseconds after the pulsed excitation, the density of the initial electronic system rapidly decreases down to reach that of a stable electron-hole liquid phase. The comparison of the PL intensity decay time of Au-SiNWs with high crystalline quality and purity silicon layer allows us to conclude that the Au-SiNW electronic properties are highly comparable to those of bulk silicon crystal.

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    • "Finally, VLS processes do not allow to obtain Si NWs with radii lower than a critical values of tens of nanometers, far beyond the quantum confinement threshold [9]; the latter limitation holds also for wires synthesized by top-down lithographic processes. In agreement with the above considerations, the observation of photoluminescence (PL) from Si NWs has been attributed to the presence of N-containing complexes [10] or to the phonon-assisted low temperature recombination of photogenerated carriers [11]. PL from Si NWs due to quantum confinement has been only obtained by reducing, through thermal oxidation processes, the diameter of NWs obtained by plasma etching of a Si wafer [12] [13], or by a TiSi 2 -catalyzed VLS growth [14]. "

    Full-text · Dataset · Jan 2016
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    • "Finally, VLS processes do not allow to obtain Si NWs with radii lower than a critical values of tens of nanometers, far beyond the quantum confinement threshold [9]; the latter limitation holds also for wires synthesized by top-down lithographic processes. In agreement with the above considerations, the observation of photoluminescence (PL) from Si NWs has been attributed to the presence of N-containing complexes [10] or to the phonon-assisted low temperature recombination of photogenerated carriers [11]. PL from Si NWs due to quantum confinement has been only obtained by reducing, through thermal oxidation processes, the diameter of NWs obtained by plasma etching of a Si wafer [12] [13], or by a TiSi 2 -catalyzed VLS growth [14]. "

    Full-text · Dataset · Jan 2016
  • Source
    • "Finally, VLS processes do not allow to obtain Si NWs with radii lower than a critical values of tens of nanometers, far beyond the quantum confinement threshold [9]; the latter limitation holds also for wires synthesized by top-down lithographic processes. In agreement with the above considerations, the observation of photoluminescence (PL) from Si NWs has been attributed to the presence of N-containing complexes [10] or to the phonon-assisted low temperature recombination of photogenerated carriers [11]. PL from Si NWs due to quantum confinement has been only obtained by reducing, through thermal oxidation processes, the diameter of NWs obtained by plasma etching of a Si wafer [12] [13], or by a TiSi 2 -catalyzed VLS growth [14]. "
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