Crystalline properties of ε-Ga2O3 film grown on c-sapphire by MOCVD and solar-blind ultraviolet photodetector

Heterogeneous epitaxy of ε-Ga2O3 films on c-plane sapphire was carried out by metal-organic chemical vapor deposition. The crystal quality and epitaxial relationship were investigated by X-ray diffraction and transmission electron microscopy. The effects of the thickness changing on crystal quality and morphology of ε-Ga2O3 films were analyzed. A higher quality ε-Ga2O3 film with full width at half maxima of 0.46° was obtained at 480 nm. A ε-Ga2O3 metal-semiconductor-metal solar blind ultraviolet photodetector with large on/off ratio of over 2 × 103, peak responsivity of 146 A/W and detectivity of 1.2 × 1013 Jones was fabricated, indicating good optical properties of the ε-Ga2O3 film.