The different carbonization processes of a Si(111) 7 × 7 reconstructed surface exposed to acetylene (C2H2) were studied by ultrahigh-vacuum electronic and luminescence techniques. We found that the molecule breaks at about 450°C and for temperature up to 600°C a Si1-xCx alloy is formed in the near-surface region of the sample. For higher temperatures, up to 850°C, crystalline SiC crystalline precipitation epitaxially grown on the Si surface is observed. The luminescence spectra obtained at each stage of carbonization revealed the formation of well defined Si1-xCx phases (with x equal to a few per cent) and it clearly demonstrates that the exposure to C2H2 is highly efficient procedure to change in a continuous way the near-infrared optical properties of Si surface in the spectral range from 0.9 to 1.1 eV. The observation at 650°C exposure of an intense and broadened photoluminescence emission in the range 1.2-1.6 eV is particularly interesting. This indicates the possibility that in the near-surface region a local concentration of the first-nearest-neighbour Si-C bond of between 15-20% is present, indicating the formation of a high C-rich layer.
DE CRESCENZI, M., Bernardini, R., Gunnella, R., Castrucci, P., Casalboni, M., Pizzoferrato, R., et al. (2000). Interaction of acetylene on Si(111): Growth and luminescence study of Si1-xCx thin layers. ??????? it.cilea.surplus.oa.citation.tipologie.CitationProceedings.prensentedAt ??????? International Workshop on Semiconducting and Superconducting Materials, Torino, ita [10.1080/014186300255311].
Interaction of acetylene on Si(111): Growth and luminescence study of Si1-xCx thin layers
DE CRESCENZI, MAURIZIO;CASTRUCCI, PAOLA;CASALBONI, MAURO;PIZZOFERRATO, ROBERTO;
2000-01-01
Abstract
The different carbonization processes of a Si(111) 7 × 7 reconstructed surface exposed to acetylene (C2H2) were studied by ultrahigh-vacuum electronic and luminescence techniques. We found that the molecule breaks at about 450°C and for temperature up to 600°C a Si1-xCx alloy is formed in the near-surface region of the sample. For higher temperatures, up to 850°C, crystalline SiC crystalline precipitation epitaxially grown on the Si surface is observed. The luminescence spectra obtained at each stage of carbonization revealed the formation of well defined Si1-xCx phases (with x equal to a few per cent) and it clearly demonstrates that the exposure to C2H2 is highly efficient procedure to change in a continuous way the near-infrared optical properties of Si surface in the spectral range from 0.9 to 1.1 eV. The observation at 650°C exposure of an intense and broadened photoluminescence emission in the range 1.2-1.6 eV is particularly interesting. This indicates the possibility that in the near-surface region a local concentration of the first-nearest-neighbour Si-C bond of between 15-20% is present, indicating the formation of a high C-rich layer.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
