Recombination-Enhanced Dislocation Glide in 4H-SiC and GaN under Electron Beam Irradiation

The results of studying the recombination-enhanced dislocation motion in GaN and 4H-SiC have been analyzed. It is shown that in both crystals, when irradiated by a low-energy electron beam, dislocations can shift at liquid nitrogen temperature. The activation energies of the dislocation glide stimulated by electron beam irradiation are estimated. Results demonstrating practically activation-free migration of double kinks along a 30° partial Si-core dislocation in 4H-SiC are presented. It is shown that localized obstacles significantly affect the dislocation motion in GaN both under the action of shear stresses and under irradiation. The excess charge carriers introduced into GaN by irradiation not only help to overcome the Peierls barrier but also stimulate dislocation unpinning from obstacles.