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


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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