On the mechanism of lattice electromigration in metals

Values of the “residual resistivity” B for ions of silver diffused into copper and gold over a temperature range above 0,8 T m are calculated on the basis of data taken from a previous paper of Archipova, Klotsman, Timofeev, and Trakhtenberg [1]. These values of B are compared with values of the residual resistivity for substitution and interstitial impurity ions in group I noble metals. This shows that scattering by the diffused ions occupying interstitial positions gives the main contribution to the driving force of the activated complex. The observed temperature dependence of B and the order of magnitude of the temperature coefficients ( B −1 ∂ B /∂ T ≈ 10 −4 deg −1 ) can be explained by the interaction of impurity ions in interstitial positions with the surrounding lattice. As a first approximation this interaction can be considered as a mutual deformation of the impurity ion and the lattice. Using this approximation it is possible to estimate the magnitude of B for impurities from various parts of the periodic table in a given lattice.