Up to 3.7 A Operation of E-mode MOSFET based on Heteroepitaxial ε-Ga₂O₃

Ultra-wide bandgap Gallium oxide (Ga<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>) has emerged as a promising candidate for next-generation high-power electronic devices due to its exceptional material properties [1]. Among its polymorphs, $\varepsilon$ Ga<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>, the second most stable phase, exhibits unique advantages such as high-quality heteroepitaxial growth and strong polarization effects, making it particularly attractive for advanced device applications [2]. In prior work, we demonstrated the successful fabrication of heteroepitaxial $\varepsilon$ - Ga<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> MOSFETs on sapphire substrates using metal-organic chemical vapor deposition (MOCVD) combined with a fluorine plasma surface doping technique [3]. While recent research has predominantly focused on achieving high power figures of merit (PFOM) and exploring novel device architectures, the realization of large-area devices capable of sustaining high output currents remains critical for practical applications [4]. However, the development of large-area Ga<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> transistors is hindered by challenges such as non-uniform material growth and process variability. In this study, we present an enhancement-mode (E-mode) $\varepsilon-\mathrm{Ga}_{2} \mathrm{O}_{3}$ MOSFET achieving a record output current of 3.7 A, underscoring its potential for high-power applications.