Summary Of The Progress In Beta-Phase Gallium Oxide Field-Effect Transistors

A technical paper titled “Progress in Gallium Oxide Field-Effect Transistors for High-Power and RF Applications” was published by researchers at George Mason University and National Institute of Standards and Technology (NIST).

Abstract:

“Power electronics are becoming increasingly more important, as electrical energy constitutes 40% of the total primary energy usage in the USA and is expected to grow rapidly with the emergence of electric vehicles, renewable energy generation, and energy storage. New materials that are better suited for high-power applications are needed as the Si material limit is reached. Beta-phase gallium oxide (β-Ga₂O₃) is a promising ultra-wide-bandgap (UWBG) semiconductor for high-power and RF electronics due to its bandgap of 4.9 eV, large theoretical breakdown electric field of 8 MV cm⁻¹, and Baliga figure of merit of 3300, 3–10 times larger than that of SiC and GaN. Moreover, β-Ga₂O₃ is the only WBG material that can be grown from melt, making large, high-quality, dopable substrates at low costs feasible. Significant efforts in the high-quality epitaxial growth of β-Ga₂O₃ and β-(Al_xGa_1−x)₂O₃ heterostructures has led to high-performance devices for high-power and RF applications. In this report, we provide a comprehensive summary of the progress in β-Ga₂O₃ field-effect transistors (FETs) including a variety of transistor designs, channel materials, ohmic contact formations and improvements, gate dielectrics, and fabrication processes. Additionally, novel structures proposed through simulations and not yet realized in β-Ga₂O₃ are presented. Main issues such as defect characterization methods and relevant material preparation, thermal studies and management, and the lack of p-type doping with investigated alternatives are also discussed. Finally, major strategies and outlooks for commercial use will be outlined.”

Find the technical paper here. Published December 2023.

Maimon, O. and Li, Q. (2023), Progress in Gallium Oxide Field-Effect Transistors for High-Power and RF Applications, Materials, [online], https://doi.org/10.3390/ma16247693, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=956899 (Accessed January 8, 2024)

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