Research on the surface morphology of ß-Ga2O3films with different growth conditions

ß-Ga
2
O
3
heteroepitaxial films were deposited on c-plane sapphire substrates by MOCVD epitaxial growth technology. The influence of different growth conditions such as growth temperature, growth pressure and substrate mis-cutting angle on crystal quality and surface morphology of epitaxial films were systematically investigated. In our study, as the temperature decreased from 950 to 800°C, the surface morphology of epitaxial films showed a trend of gradual improvement. However, the films obtained at less than 800°C were mostly amorphous structures. With the decrease of growth pressure and the increase of substrate mis-cutting angle, the surface morphology of films also improved gradually. By optimizing the experimental design, the better quality ß-Ga
2
O
3
epitaxial films were obtained at 800°C, 40 Torr and 8° of substrate mis-cutting angle. This work can serve as an essential reference for ß-Ga
2
O
3
heteroepitaxy, which is beneficial for developing high performance ß-Ga
2
O
3
radio frequency (RF) devices.