Structural and optical properties of A12O3 with Si and Ge nanocrystals

Date

2006-12-01

Author

Yerci, Selçuk
Kara, İlkim Merve
Serincan, Ugur
Shandalov, Michael
Golan, Yuval
Turan, Raşit

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Si and Ge nanocrystals were formed in Al2O3 matrix by ion implantation and subsequent annealing. The phase separation of the Si nanocrystals was observed using X-ray photoelectron spectroscopy by monitoring Si 2p electrons. During nanocrystal formation with a high temperature annealing Si-0 signals corresponding to Si nanoclusters increase while Si4+ signals related to a-SiO2 disappear from the spectrum. The transition from amorphous to nanocrystalline phase for both Si and Ge nanoclusters and the compressive stress exerted on the formed nanocrystals were also studied by Raman spectroscopy. Photoluminescence spectra of the Al2O3 containing nanocrystals were discussed by means of Ti and Cr impurities, as well as F centers. The existence of the amorphous Ge nanoclusters in Al2O3 matrix significantly enhances the light emission of Ti3+ impurities.

Subject Keywords

Silicon nanocrystals, Oxide

URI

https://hdl.handle.net/11511/55549

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Graduate School of Natural and Applied Sciences, Conference / Seminar

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Structural and optical properties of Al2O3 with Si and Ge nanocrystals Yerci, Selçuk; Yıldız, İlker; Serincan, Ugur; Shandalov, Michael; Golan, Yuval; Turan, Raşit (2007-07-04) Si and Ge nanocrystals were formed in Al2O3 matrix by ion implantation and subsequent annealing. The phase separation of the Si nanocrystals was observed using X-ray photoelectron spectroscopy by monitoring Si 2p electrons. During nanocrystal formation with a high temperature annealing Si4+ signals corresponding to Si nanoclusters increase while Si 4+ signals related to a-SiO2 disappear from the spectrum. The transition from amorphous to nanocrystalline phase for both Si and Ge nanoclusters and the compress...
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Citation Formats

S. Yerci, İ. M. Kara, U. Serincan, M. Shandalov, Y. Golan, and R. Turan, “Structural and optical properties of A12O3 with Si and Ge nanocrystals,” 2006, vol. 958, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/55549.