Effect of Impurities on the Individual Dislocation Mobility in Silicon

An investigation was made of the dependence of individual 60° and screw dislocation velocities on stress, temperature, and impurity (B, As, Sb) concentration in silicon single crystals. It was found that both donor and acceptor impurities result in decrease of the activation energy ( U ) of the dislocation motion. The donor influence on U is stronger. The possible reasons for the observed phenomenon are analysed in terms of the effect of impurities on the mechanism of overcoming of Peierls stresses by a dislocation.