Presentation Information
[16p-W9_324-5]Epitaxial Growth of Gallium Oxide (2): Homoepitaxial Growth of β-Ga2O3 on Sn-doped Ga2O3 Substrates Using a Novel High-Density Oxygen Radical Source (HD-ORS) for MBE
〇ArunKumar Dhasiyan1, Tomoki Takeda2, Naofumi Kato2, Naohiro Shimizu1, Osamu Oda1,2, Masaru Hori1 (1.Nagoya Univ., CLPS, 2.NU-Rei, Inc.)
Keywords:
gallium oxide,HD-ORS,homoepitaxy
β-Ga2O3 is attracting strong interest for power electronics such as EVs, switching devices, solar-blind photodetectors, and MESFETs due to its advantages over Si, SiC and GaN. Homoepitaxy on β-Ga2O3 substrates enables high crystalline quality, supported by the availability of melt-grown single-crystal substrates (EGF, Czochralski) in multiple orientations ((100), (001), (-201), (010)). However, Molecular Beam Epitaxy (MBE) suffers from low growth rates caused by two-step kinetics: formation of volatile Ga2O and its subsequent oxidation. The Ga2O has a significantly higher vapor pressure than Ga, its desorption limits the growth rate due to two factors (1) metal-rich conditions, providing insufficient O-flux to oxidize all formed suboxide, and (2) high substrate temperatures (Tg) at which the thermally activated desorption of Ga2O outperforms its oxidation even under O-rich growth conditions.
To address this, we explore low-temperature β-Ga2O3 growth using a high-density RF plasma source capable of generating abundant atomic oxygen. Our newly developed High-Density Oxygen Radical Source (HD-ORS) activates O3-O2 to enable efficient oxidation at reduced temperatures. Here, we present preliminary MBE homoepitaxy results on Sn-doped β-Ga2O3 substrates grown at 300 oC with the growth rate of 1 µm/hr, followed by X-ray Diffraction (XRD) and Scanning Electron Microscope (SEM) characterizations.
To address this, we explore low-temperature β-Ga2O3 growth using a high-density RF plasma source capable of generating abundant atomic oxygen. Our newly developed High-Density Oxygen Radical Source (HD-ORS) activates O3-O2 to enable efficient oxidation at reduced temperatures. Here, we present preliminary MBE homoepitaxy results on Sn-doped β-Ga2O3 substrates grown at 300 oC with the growth rate of 1 µm/hr, followed by X-ray Diffraction (XRD) and Scanning Electron Microscope (SEM) characterizations.