Growth of Ga2O3 film on ScAlMgO4 substrate by mist-chemical vapor deposition

ScAlMgO4 (SAM) substrates have a trigonal structure with high cleavability in the c-plane. Because this substrate can be easily cleaved, gallium oxide (Ga2O3) can be grown on the SAM substrate, and the difficulty in the heat dissipation of Ga2O3 may be solved. Therefore, in this study, we performed Ga2O3 growth on a SAM substrate using mist-chemical vapor deposition. When the growth temperature was varied at 500 °C, 600 °C, and 700 °C, ε-Ga2O3(004) grew dominantly, and the crystallinity improved with increasing temperature. Moreover, the grown ε-Ga2O3 had orthorhombic structure and formed rotational domains. Furthermore, a phase transition to β-Ga2O3 was achieved by annealing the resulting ε-Ga2O3 on the SAM substrates. We also succeeded in separating the SAM substrates on which the Ga2O3 thin films were grown.