【Epitaxy Papers】Epitaxy of corundum-like α-Ga₂O₃ on wurtzite 6H-SiC via Mist-CVD Cr₂O₃ double buffer layer

      Researchers from the Perfect Crystals LLC have published a dissertation titled "Epitaxy of corundum-like α-Ga₂O₃ on wurtzite 6H-SiC via Mist-CVD Cr₂O₃ double buffer layer" in Materials Today Communications.

Abstract

      Silicon carbide, SiC, is a prospective substrate for epitaxial deposition of gallium oxide, Ga₂O₃, layers due to its high thermal conductivity, which is crucial for power electronic devices. Here we focus on the heterojunction of hexagonal 6H-SiC with metastable α- Ga₂O₃. It has a robust corundum structure with both higher radiation resistance and a value of bandgap, ∼ 5.3 eV, over thermostable β-phase gallium oxide, 4.7 eV. The combination of p-type silicon carbide with n-type of α-Ga₂O₃ in their heterostructures looks very attractive for various applications, but previously it was deemed unlikely to acquire α-Ga₂O₃ on SiC substrates due to the preferred formation of the pseudohexagonal κ-phase of gallium oxide. Here we report that for the first time α-Ga₂O₃ layers were successfully grown on highly thermally conductive 6H-SiC crystal via mist-CVD double Cr₂O₃ buffer layers, which changed Ga₂O₃ epi-layers growth from orthorhombic κ-phase to corundum α-phase structure. Thick HVPE α-Ga₂O₃ was grown on the top of the Mist-CVD α-Ga₂O₃/Cr₂O₃/6H-SiC template, forming a bulk heterostructure.

DOI：

https://doi.org/10.1016/j.mtcomm.2025.113943