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arXiv · 1805.10117

Quantitative relevance of substitutional impurities to carrier dynamics in diamond

Takaaki Shimomura·Yoshiki Kubo·Julien Barjon·Norio Tokuda·Ikuko Akimoto·Nobuko Naka
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Abstract

We have quantified substitutional impurity concentrations in synthetic diamond crystals down to sub parts-per-billion levels. The capture lifetimes of electrons and excitons injected by photoexcitation were compared for several samples with different impurity concentrations. Based on the assessed impurity concentrations, we have determined the capture cross section of electrons to boron impurity, sA=1.3x10^-14 cm2, and that of excitons to nitrogen impurity, sD^ex=3.1x10^-14 cm2. The general tendency of the mobility values for different carrier species is successfully reproduced by including carrier scattering by impurities and by excitons.

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Takaaki Shimomura, Yoshiki Kubo, Julien Barjon, Norio Tokuda, Ikuko Akimoto, Nobuko Naka. 2018-05-25. Quantitative relevance of substitutional impurities to carrier dynamics in diamond. https://doi.org/10.1103/physrevmaterials.2.094601

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