【Epitaxy Papers】Temperature-dependent vapor-phase nucleation and surface migration in CVD-grown β-Ga₂O₃ epilayers on 4H-SiC substrate

      Researchers from the Institute of Semiconductors, Chinese Academy of Sciences have published a dissertation titled "Temperature-dependent vapor-phase nucleation and surface migration in CVD-grown β-Ga₂O₃ epilayers on 4H-SiC substrate" in Vacuum.

Abstract

      In this study, β-Ga₂O₃ films were grown on 4H-SiC substrates with varying off-axis angles using low-pressure chemical vapor deposition (LPCVD). Elemental Ga and O₂ were employed as sources, simplifying the process and ensuring high elemental purity. The prepared samples were thoroughly characterized using scanning electron microscopy (SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray photoelectron spectroscopy (XPS). Results revealed that layered growth is optimized on 4° off-axis (0001) substrate at 680 °C. A growth mechanism was proposed to clarify the relationship between surface morphology and growth conditions. The study demonstrates that precise control of growth parameters can suppress vapor-phase nucleation and associated surface irregularities, enhancing surface cleanliness and smoothness. This approach enables the growth of pure β-Ga₂O₃ films on 4H-SiC, making them suitable for advanced device applications.

DOI：

https://doi.org/10.1016/j.vacuum.2025.114643