Dissociation of dislocations in diamond

Abstract

Weak-beam electron microscopy has been applied to study the dissociation of dislocations in a type IIa diamond. Dislocations with Burgers vector $\frac{1}{2}$[1$\bar{1}$0] on (111) glide planes have been found to be dissociated into two Shockley partials, with separations between 2.5 and 4.3 nm, and extended nodes and dissociated dipoles have also been observed. The stacking fault energy has been determined from the mean and distribution of the separations of the partials to be 279 $\pm$ 41 mJ m$^{-2}$. The behaviour of dislocations in diamond appears to be similar to that of dislocations in Ge and Si.