Interaction of doping impurities with the 30-degree partial dislocations in SiC: an ab initio investigation

In this work we investigated, by means of state-of-the-art first principle techniques, the effect of impurity segregation on the energetics, the structure, and the electronic properties of dislocation cores. We find that for the species we considered, Al, P, B, and N, i.e., the most common dopants in SiC, the impurity-dislocation interaction is attractive and that segregation energies are comparable or larger than dislocations reconstruction energies. As to the doping properties of the impurities they are deactivated by the interaction with the dislocation core environment, with the noticeable exception of P. We rationalized our results in terms of the effect of the dopants on the dislocation core band structure.