Silicon nanocrystals oxidized

Wilcoxon JP, Samara GA, Provencio PN (1999) Optical and electronic properties of Si nanoclusters synthesized in inverse micelles. Phys Rev B 60 2704-2714 Wilson WL, Szajowski PF, Brus LE (1993) Quantum confinement in size-selected surface-oxidized silicon nanocrystals. Science 262 1242-1244... 

A DNA biosensor based on various porous silicon layers was fabricated using an oxidized microcavity resonator design developed by Chan et al. [37], the porous sihcon containing silicon nanocrystals that can luminescence efficiently in the visible. 

Zhou ZY, Brus L, Friesner R (2003) Electronic structure and luminescence of 1.1- and 1.4-nm silicon nanocrystals oxide shell versus hydrogen passivation. Nano Lett 3 163-167... 

During the last few years, we have studied silicon nanocrystals produced by CO2 laser pyrolysis of silane and we have been able to show that, in these experiments, the PL characteristics can be unambiguously explained in terms of quantum confinement effects.However, to observe the photoluminescence with the naked eye, we had to wait a few hours or even a few days. It appeared that the silicon nanocrystals were passivated by natural aerial oxidation and that, with time, the photoluminescence became more and more intense. 

Takeda E, Nakamura T, Fujii M, Miura S, Hayashi S (2006) Surface plasmon polariton mediated photoluminescence from excitons in silicon nanocrystals. Appl Phys Lett 89(10) 101907 Tsybeskov L, Duttagupta SP, Fauchet PM (1995) Photoluminescence and electroluminescence in partially oxidized porous silicon. Solid State Commun 95(7) 429-433 Tsybeskov L, Duttagupta SP, Hirschman KD, Fauchet PM (1996) Stable and efficient electroluminescence from a porous silicon-based bipolar device. Appl Phys Lett 68(15) 2058-2060 Valenta J, Lalic N, Linnros J (2004) Electroluminescence of single silicon nanocrystals. Appl Phys Lett 84(9) 1459-1461... 

Depending mostly on the degree of quantum confinement and on the chemical state of its surface, porous silicon could luminesce from the near-infrared ( 1.5 pm) to the near-UV as a result of distinct emission bands having different origins (Table 2 Cullis et al. 1997 Bisi et al. 2000). The near-infrared band has not been as extensively studied as the visible bands. It was observed in both partially oxidized porous silicon and oxygen-lfee samples. It has been related to both quantum-size effect and surface states (Koch et al. 1993). The UV band has been observed only in oxidized porous silicon. It has been related to oxide luminescence, with the silicon nanocrystals playing a potential role in the photoexcitation process(Qin et al. 1996). 

Hessel CM, Henderson EJ, Kelly JA, Cavell RG, Sham TK, Veinot JCG (2008) Origin of luminescence from silicon nanocrystals a near edge X-ray absorption fine structure (NEXAFS) and X-ray excited optical luminescence(XEOL) study of oxide-embedded and free-standing systems. J Phys ChemC 112 14247-14254... 

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