Electronically induced dislocation glide motion in hexagonal GaN single crystals

Abstract

Dislocations in crystalline powder of hexagonal GaN intentionally deformed by crushing were examined by transmission electron microscopy (TEM) in order to see if the recombination enhanced dislocation glide (REDG) effect is present in this solid. It was found that dislocations with a Burgers vector of a-type (a/3〈112̄0〉) on the (0001) basal plane and a {11̄0n} pyramidal plane exhibit glide motion at room temperature under the influence of the electron beam used for TEM observations. From a quantitative comparison with the thermal mobility of basal dislocations empirically predicted for h-GaN, the authors concluded that the dislocation glides arose from the REDG effect induced by electronic excitation due to the TEM electron beam irradiation. Some implications of the results were discussed.