Theory of Dislocation Mobility in Semiconductors

A new model for dislocation motion appropriate for crystals having high Peierls stress is presented. The model makes use of dragging points on the dislocation which restrict the free motion of kinks on the line. It predicts a dislocation velocity with an exponential dependence inverse in the stress and an activation energy appropriate to kink nucleation. In extensive Appendixes, kink theory is used to develop explicit formulas for the stress dependence of the kink nucleation energy and to work out the statistical details of the nucleation rate. Also, a detailed theory of kink collisions is developed when the kink population is high. Finally, the experiments of Kabler described in the previous paper of this journal are interpreted in terms of the model with appropriate parameters for Ge.