【Epitaxy Papers】Structural and Electrical Properties of Si-Doped β-Ga₂O₃ Thin Films Deposited by RF Sputtering: Effects of Oxygen Flow Ratio and Post-Annealing Temperature

      Researchers from the Gachon University have published a dissertation titled "Structural and Electrical Properties of Si-Doped β-Ga₂O₃ Thin Films Deposited by RF Sputtering: Effects of Oxygen Flow Ratio and Post-Annealing Temperature" in Coatings.

Abstract

      Beta-gallium oxide (β-Ga₂O₃) is a semiconductor with an ultra-wide bandgap, high optical transparency, and excellent electrical properties, which can be finely tuned for a wide range of electronic devices. This study optimized the process conditions for fabricating β-Ga₂O₃ thin films with desired electrical characteristics. β-Ga₂O₃ films were deposited on (100) Si substrates via RF magnetron sputtering with varying O₂ flow rates and post-annealed at temperatures ranging from 600 °C to 800 °C. The structural and electrical properties of the films were analyzed using X-ray diffraction (XRD) spectroscopy, scanning electron microscopy (SEM), and Hall effect measurements. The XRD results confirmed the formation of nanocrystalline β-Ga₂O₃, with variations in peak intensities and shifts observed based on O₂ flow rates. The films exhibited carrier concentrations exceeding 5 × 10²² cm⁻³, mobilities ranging from 50 to 115 cm²/Vs, and resistivity around 1 × 10⁻⁶ Ω⋅cm. This study demonstrates that the electrical properties of β-Ga₂O₃ thin films can be modulated during the deposition and post-annealing processes. The ability to control these properties underscores the potential of β-Ga₂O₃ for advanced applications in high-performance high-power devices and optoelectronic devices such as deep ultraviolet photodetectors.

DOI：

https://doi.org/10.3390/coatings15101181