【Epitaxy Papers】Effect of interfacial defects on the electronic properties of β-Ga₂O₃: coupling of lattice distortions and electron localized states

      Researchers from the Henan Normal University have published a dissertation titled "Effect of interfacial defects on the electronic properties of β-Ga₂O₃: coupling of lattice distortions and electron localized states" in Chinese Journal of Physics.

Abstract

      Monoclinic gallium oxide (β-Ga₂O₃) is a promising ultra-wide-bandgap semiconductor, yet its p-type conduction is limited by strong hole localization due to self-trapped polaron formation. During the epitaxial growth, lattice mismatch and growth inhomogeneity inevitably introduce interface defects, such as dislocations and twin boundaries. The effects of these defects on electronic properties and hole transport mechanisms are not yet fully clarified. To address this, we systematically investigate how interfacial defects impact the electronic properties of β-Ga₂O₃. The interfacial symmetry breaking and local lattice distortions modify the O coordination, leading to shallow defect states dominated by O-2p (p_z and p_y) orbitals. The electronic states arising from interface defects can interact with localized hole states in the host material, which may lead to the delocalization of holes. The interfacial symmetry breaking inhibits the formation of self-trapped hole polarons by reducing the availability of delocalized states near the Fermi level. This finding provides theoretical insights into how defect-assisted orbital reconfiguration may be exploited to overcome transport limitations in wide-bandgap oxides.

DOI：

https://doi.org/10.1016/j.cjph.2025.10.020