Gettering efficiencies of Σ=25, Σ=13 and Σ=9 silicon bicrystals

The gettering efficiencies of Σ=25, Σ=13 and Σ=9 grain boundaries (GBs) have been studied by means of EBIC measurements on quenched silicon bicrystals precontaminated by Cu or Ni. The gettering " strength " of each GB has been correlated to the appearance and extent of a denuded zone (DZ) on either side of the GB. For both contaminants, the same scaling of the gettering efficiencies, namely Σ=9≪Σ=13<Σ=25, has been observed. In order to account for this ranking, theoretical calculations of the GB structures and related free energies have been performed by means of molecular dynamics simulations using several potentials These calculations provided the same progression for the interfacial energies, which was found to be quite consistent with the experimental data.