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Negative oxygen vacancies in HfO$_2$ as charge traps in high-k stacks

J. L. Gavartin·D. Munoz Ramo·A. L. Shluger·G. Bersuker·B. H. Lee
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Abstract

We calculated the optical excitation and thermal ionization energies of oxygen vacancies in m-HfO$_2$ using atomic basis sets, a non-local density functional and periodic supercell. The thermal ionization energies of negatively charged V$^-$ and V$^{2-}$ centres are consistent with values obtained by the electrical measurements. The results suggest that negative oxygen vacancies are the likely candidates for intrinsic electron traps in the hafnum-based gate stack devices.

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J. L. Gavartin, D. Munoz Ramo, A. L. Shluger, G. Bersuker, B. H. Lee. 2006-05-24. Negative oxygen vacancies in HfO$_2$ as charge traps in high-k stacks. https://doi.org/10.1063/1.2236466

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