On the mobility of partial dislocations in silicon

Abstract

Abstract The influence of high external stress (τ ≤ 340 N/mm2 on the dissociation of dislocations in silicon has been investigated. At 420°C the dislocations are strictly parallel to 〈110〉 directions. From the orientation of the compression axis a reduction in the dissociation width is to be expected. We have found screw dislocations to be widened. The reaction of the 60° dislocations depends on the order of the partial dislocations : if the 90° partial leads, the width is enlarged too, but if the 30° partial leads, it is narrowed. These findings are interpreted by taking into account the friction forces acting on the different types of partials. The increase in the width of the screw dislocations indicates that the mobility depends not only on the character of the partial (30° or 90°) but also on its position with respect to the stacking fault. The different mobilities of the 60° segments of a dislocation loop found by several authors may be deduced from our results.