Epitaxial gallium oxide on a SiC/Si substrate

Well-textured gallium oxide $\beta$-Ga$_{2}$O$_{3}$ layers with a thickness of $\sim$1 $\mu$m and a close to epitaxial layer structure were grown by the method of chloride vapor phase epitaxy on Si(111) wafers with a nano-SiC buffer layer. In order to improve the growth, a high-quality silicon carbide buffer layer $\sim$100 nm thick was preliminarily synthesized by the substitution of atoms on the silicon surface. The $\beta$-Ga$_{2}$O$_{3}$ films were thoroughly investigated using reflection high-energy electron diffraction, ellipsometry, X-ray diffraction, scanning electron microscopy, and micro-Raman spectroscopy. The investigations revealed that the films are textured with a close to epitaxial structure and consist of a pure $\beta$-phase Ga$_{2}$O$_{3}$ with the ($\bar2$01) orientation. The dependence of the dielectric constant of epitaxial $\beta$-Ga$_{2}$O$_{3}$ on the photon energy ranging from 0.7 to 6.5 eV in the isotropic approximation was measured.