Study on Single Crystal β-Ga₂O₃ Thin Films Grown by MOCVD Homoepitaxy

Ga₂O₃ films were homoepitaxy grown on Fe-doped Ga₂O₃ (010) semi-insulating substrate by metal-organic chemical vapor deposition (MOCVD). The effects of chamber temperature (880/830/780/730℃) and pressure (80/60/40/20 Torr) on the surface morphology, crystal quality and electrical properties of epitaxial films were systematically investigated. The results show that with the increasement of the growth temperature and pressure, the growth rate of the films increases slightly and decreases dramatically, respectively; The growth pattern of step bunching on the surface of the films is gradually enhanced, and the morphology is dominated by elongated grains oriented along the 001 direction; High resolution X-ray diffraction (XRD) scanning shows that only diffraction peaks exist on (020) plane, which indicates that the films are pure β-phase single crystal, and the full width at half maximum can reach 45.7 arcsec; Hall test shows that the film has the highest room temperature electron mobility under the growth conditions of 780℃ and 60 Torr, respectively. This paper provides a systematic parameter guidance for the homoepitaxy growth of Ga₂O₃ based on MOCVD, and lays a foundation for the preparation of high-quality Ga₂O₃ films.