The surface of -Ga₂O₃ single crystals cleaved along their (100) plane is investigated using surface X-ray diffraction and atomic force microscopy. The results show that the crystal cleaves at planes formed by edge-sharing oxygen octahedra, thereby breaking the longest and weakest Ga-O bonds. As a consequence, the exposed (100) surface is non-polar in nature. Owing to the crystal symmetry, terraces separated by half the a-axis length of approx. 0. 6 nm are formed. These results are important in view of the use of -Ga₂O₃ in thin film form, as exfoliated nano-belts or as nanoribbons in semiconductor high-power applications.
Kao et al. (Thu,) studied this question.