【Others Papers】New insight into the phase stability and comprehensive properties of Ga₂O₃ oxides for third generation semiconductor applications

      Researchers from the SouthWest Petroleum University have published a dissertation titled " New insight into the phase stability and comprehensive properties of Ga₂O₃ oxides for third generation semiconductor applications " in Materials Science in Semiconductor Processing.

Abstract

      Although Ga₂O₃ oxide is a promising third generation semiconductor material due to the wider band gap and larger breakdown voltage, the phase stability and overall properties of these Ga₂O₃ oxides (except for β-Ga₂O₃) are unclear. In particular, the mechanical and thermodynamic properties of these Ga₂O₃ oxides are also unknown. To solve these problems, we apply the first-principles to investigate the phase stability, mechanical, electronic and thermodynamic properties of five Ga₂O₃ oxides. The result shows that α-Ga₂O₃, β-Ga₂O₃, δ-Ga₂O₃, and ε-Ga₂O₃ are thermodynamical and dynamical stabilities based on the formation enthalpy and phonon dispersion. However, the cubic (Fd-3m) γ-Ga₂O₃ is a dynamical instability. Furthermore, it is found that α-Ga₂O₃ has strong volume deformation resistance, shear deformation resistance and high elastic stiffness in comparison to β-Ga₂O₃ and δ-Ga₂O₃ oxides, while the Vickers hardness of α-Ga₂O₃ is also bigger than the other Ga₂O₃ oxides. Importantly, the band gap of α-Ga₂O₃ is bigger than that of β-Ga₂O₃, δ-Ga₂O₃ and ε-Ga₂O₃. The wider band gap of Ga₂O₃ is related to the wide valley of O-2p state between the Fermi level and conduction band. We further find that three Ga₂O₃ oxides exhibit better ductility. Finally, β-Ga₂O₃ has better thermal stability in comparison to α-Ga₂O₃, δ-Ga₂O₃ and ε-Ga₂O₃ oxides.

DOI：

https://doi.org/10.1016/j.mssp.2025.109747