Mechanical properties and dislocation dynamics in β-Ga2O3

The mechanical and dislocation properties of beta-Ga2O3 were investigated. Vickers indentations were used to make fractures on the (010)-, (001)-, and (201)-oriented substrates. Sharp cracks along the (100) and (001) planes were observed near the impressions on the (010)-oriented substrate. The cracks were identified as cleavages on the planes, which were parallel to the indentation load. The Vickers hardness was smaller for the (010)-oriented substrate than for the (001)- and (201)-oriented substrates, indicating that the indentation flow activated the cleavages. The small Vickers hardness for the (010)-substrate suggested that the (010) surface is fragile. Dislocation evolution in the (001)-plane was also caused by heat treatment after the indentations were made. This observation indicated that the dislocations were formed by slips on the (001) plane, which suggested that the (001) plane is a slip plane in this material. (C) 2022 The Japan Society of Applied Physics