Disorder-Induced Ordering in Gallium Oxide Polymorphs

Polymorphs are common in nature and can be stabilized by applying external pressure in materials. The pressure and strain can also be induced by the gradually accumulated radiation disorder. However, in semiconductors, the radiation disorder accumulation typically results in the amorphization instead of engaging polymorphism. By studying these phenomena in gallium oxide we found that the amorphization may be prominently suppressed by the monoclinic to orthorhombic phase transition. Utilizing this discovery, a highly oriented single-phase orthorhombic film on the top of the monoclinic gallium oxide substrate was fabricated. Exploring this system, a novel mode of the lateral polymorphic regrowth, not previously observed in solids, was detected. In combination, these data envisage a new direction of research on polymorphs in Ga2O3 and, potentially, for similar polymorphic families in other materials.

Automated summary

In this study, the phenomenon of polymorphism in gallium oxide is investigated. It is found that the amorphization can be significantly suppressed by the phase transition, leading to the fabrication of a highly oriented single-phase film. A novel mode of lateral polymorphic regrowth, not previously observed in solids, is also discovered. These findings open up new directions for research on polymorphs in Ga2O3 and potentially in other materials.