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arXiv · 1309.5217

Understanding H-defect complexes in ZnO

R. Vidya·P. Ravindran·H. Fjellvåg
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Abstract

From state-of-the-art density-functional calculations using hybrid functionals we show that, persistent $n$-type conductivity in ZnO is due to defect complexes formed between H with intrinsic and extrinsic defects. H exhibits cationic, anionic, and electrically-inactive character on interacting with defects in ZnO. The electrically-inactive molecular hydrogen can contribute to $n$-type conductivity in ZnO by activating deep donor levels into shallow levels. By calculating local vibrational mode frequencies, we have identified origins of many H-related Raman and infra-red frequencies and thus confirmed the amphoteric behavior of H.

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R. Vidya, P. Ravindran, H. Fjellvåg. 2013-09-20. Understanding H-defect complexes in ZnO. https://arxiv.org/abs/1309.5217

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