The stability of atomic and molecular hydrogen in the vicinity of a screw dislocation in silicon was investigated using first-principles calculations. The lowest-energy configurations were found for H atoms located in the dislocation core; thus suggesting that the segregation of hydrogen was favoured in the core. It was found that spontaneous dissociation of H2 could occur in the dislocation core. The variation of the interaction energy between hydrogen and the dislocation core, as a function of the separation distance, was also calculated. There was no appreciable interaction variation for H2. However, in the case of a single H atom, an inverse law was obtained and could be explained by the anisotropic stress field generated by the insertion of H into the silicon lattice.

Investigation of the Interaction between Hydrogen and Screw Dislocation in Silicon by First-Principles Calculations. M.Matsubara, J.Godet, L.Pizzagalli: Journal of Physics - Condensed Matter, 2010, 22[3], 035803