Radiation-enhanced dislocation glide in 4H-SiC at low temperatures

The expansion of single-layer Shockley-type stacking faults (SSFs) in 4H-SiC under low energy electron beam irradiation has been studied in the temperature range from 80 to 300 K. It is shown that the SSF expansion can be observed even at 80 K. The activation energy for gliding of the Si-core 30° partial dislocations, which drive the SSF expansion under electron beam irradiation with current in the range from 20 to 100 nA, does not exceed 6 meV. The dislocation velocity is found to linearly increase with beam current at all temperatures used in the experiment. The observed enhancement of dislocation velocity is assumed to be determined by the recombination enhanced dislocation glide mechanism. The energy redirected by the nonradiative dislocation related recombination sites to overcome the Peierls barrier is estimated to be larger than 1.3 eV.