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arXiv · 1210.2902

Extended point defects in crystalline materials: Ge and Si

Nick E. B. Cowern·Sergei Simdyankin·Chihak Ahn·Nick S. Bennett·Jonathan P. Goss·Jean-Michel Hartmann·Ardechir Pakfar·Silke Hamm·Jérôme Valentin·Enrico Napolitani·Davide De Salvador·Elena Bruno·Salvatore Mirabella
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Abstract

B diffusion measurements are used to probe the basic nature of self-interstitial 'point' defects in Ge. We find two distinct self-interstitial forms - a simple one with low entropy and a complex one with entropy ~30 k at the migration saddle point. The latter dominates diffusion at high temperature. We propose that its structure is similar to that of an amorphous pocket - we name it a 'morph'. Computational modelling suggests that morphs exist in both self-interstitial and vacancy-like forms, and are crucial for diffusion and defect dynamics in Ge, Si and probably many other crystalline solids.

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Nick E. B. Cowern, Sergei Simdyankin, Chihak Ahn, Nick S. Bennett, Jonathan P. Goss, Jean-Michel Hartmann, Ardechir Pakfar, Silke Hamm, Jérôme Valentin, Enrico Napolitani, Davide De Salvador, Elena Bruno, Salvatore Mirabella. 2013-03-12. Extended point defects in crystalline materials: Ge and Si. https://doi.org/10.1103/physrevlett.110.155501

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