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arXiv · 2103.15867

Photoluminescence of ion-synthesized 9R-Si inclusions in SiO2/Si structure: effect of irradiation dose and oxide film thickness

Alena Nikolskaya·Alexey Belov·Alexey Mikhaylov·Anton Konakov·David Tetelbaum·Dmitry Korolev
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Abstract

The study of hexagonal silicon polytypes attracts special attention due to their unique physical properties compared to the traditional cubic phase of Si. Thus, for some hexagonal phases, a significant improvement in the emission properties has been demonstrated. In this work, the luminescent properties of SiO2/Si structures irradiated with Kr+ ions at different doses and annealed at 800 °C have been systematically investigated. For such structures, a photoluminescence line at ~ 1240 nm is observed and associated with the formation of hexagonal 9R-Si phase inclusions. It is found that the variation in the thickness of oxide film and the relative position of ion distribution profile and film / substrate interface leads to a regular change in the luminescence intensity. The nature of the observed dependencies is discussed as related to the interplay between the desirable 3C-Si -> 9R-Si structural transition and generation of nonradiative defects. The revealed regularities suggest optimal ion irradiation conditions for synthesis of optically active 9R-Si phase in diamond-like silicon.

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Alena Nikolskaya, Alexey Belov, Alexey Mikhaylov, Anton Konakov, David Tetelbaum, Dmitry Korolev. 2021-03-29. Photoluminescence of ion-synthesized 9R-Si inclusions in SiO2/Si structure: effect of irradiation dose and oxide film thickness. https://doi.org/10.1063/5.0052243

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