Deformation patterns and fracture stress of beta-phase gallium oxide single crystal obtained using compression of micro-pillars

The deformation of single-crystal beta-phase gallium oxide (or β-Ga₂O₃) micro-pillars under compression was investigated with the aid of transmission electron microscopy. High-density stacking faults were the dominant deformation defects in the plastically deformed micro-pillars. Micro-cracks were found along (200), (001) and (010) lattice planes and fracture occurred along (200) lattice plane when compressive strain was sufficiently great. Lattice bending was also observed in the fractured pillar. The average fracture stress and strain of β-Ga₂O₃ being measured are 7.25 ± 1.11 GPa and 3.80 ± 0.57%, respectively, which have never been reported previously.