Growth rate control and phase diagram of wafer-scale Ga2O3 films by MOCVD

Abstract

The potential of gallium oxide (Ga2O3) as a promising semiconductor for advanced electronics and optoelectronics has been propelled by its wide bandgap, high breakdown voltage tolerance, and excellent chemical and thermal stability. To develop it into an industrial-level application, extensive research needs to be conducted to advance wafer-scale and high-quality epitaxy growth techniques. In this work, a close-coupled showerhead (CCS) metal-organic chemical vapor deposition (MOCVD) system was used to grow wafer-scale Ga2O3 films. Through a detailed examination of growth parameters including substrate temperature, oxygen flow rate, precursor proportion, and chamber pressure, as well as their effect on film crystallinity, surface morphology, and optical properties, a comprehensive growth phase diagram and control over the growth rate of 2-inch Ga2O3 thin films were obtained at a wafer-scale. These findings suggest that the CCS-MOCVD system presents a competitive avenue for future industrial high-speed fabrication of single-phase Ga2O3 films.