【Epitaxy Papers】Band Alignment of Wide-bandgap BeO Epitaxially grown on α-Ga₂O₃

      Researchers from the BK21 Graduate Program in Intelligent Semiconductor Technology have published a dissertation titled "Band Alignment of Wide-bandgap BeO Epitaxially grown on α-Ga₂O₃" in Ceramics International.

Abstract

      The development of next-generation power electronics demands ultrawide-bandgap semiconductors that can operate under extreme conditions. While α-phase gallium oxide (α-Ga₂O₃) exhibits exceptional properties, its practical application is hindered by intrinsically low thermal conductivity (8.0–11.6 W/m·K) and limited conduction band offsets (CBOs) with conventional dielectrics. In this study, we demonstrate the successful epitaxial growth of beryllium oxide (BeO) on α-Ga₂O₃ using plasma-enhanced atomic layer deposition, which provides a large CBO and suggests potential advantages in interfacial thermal properties due to the high thermal conductivity of BeO. Structural analyses using transmission electron microscopy and X-ray diffraction verified that BeO grew as a single crystal with atomically sharp interfaces, enabled by hexagonal symmetry matching. Furthermore, the band alignment was identified as type-I, with a CBO of 2.7 eV. These results indicate that BeO is a promising dielectric for α-Ga₂O₃ devices.

DOI：

https://doi.org/10.1016/j.ceramint.2026.02.354