ε-Ga2O3 thin films were grown on 4H-SiC substrates by metal organic chemical vapor deposition (MOCVD) andcrystalline quality were evaluated depend on growth conditions. It was found that the best conditions of the ε-Ga2O3 were grown at a growth temperature of 665°C and an oxygen flow rate of 200 sccm. Two-dimensional growth was completed after the merge of hexagonal nuclei, and the arrangement direction of hexagonal nuclei was closely related to the crystal direction of the substrate.
However, it was confirmed that crystal structure of the ε-Ga2O3 had an orthorhombic rather than hexagonal. Crystal phase transformation was performed by thermal treatment. And a β-Ga2O3 thin film was grown directly on 4H-SiC for the comparison to the phase transformed β-Ga2O3 thin film. The phase transformed β-Ga2O3 film showed better crystal quality than directly grown one.