Overcoming material limitations progresses of gallium oxide for power devices applications: A review

In recent years, gallium oxide (Ga₂O₃) has garnered growing attention as a next-generation ultrawide bandgap (UWBG) semiconductor, owing to its exceptional material properties namely, its wide bandgap (∼4.8 eV), high breakdown electric field, and suitability for high-efficiency and high-voltage power electronic applications. This rising interest is reflected in the increasing volume of published research and the organization of dedicated international conferences. This comprehensive review provides an in-depth overview of the intrinsic properties of Ga₂O₃ and highlights recent progress in material growth, device fabrication, and performance enhancement. Emphasis is placed on the critical challenges that currently impede the large-scale commercialization of Ga₂O₃-based devices. These include the longstanding difficulty in achieving stable p-type conductivity, the inherently low thermal conductivity, the presence of crystallographic defects such as nano- and micro-voids, the limitations of wet etching processes, and the high fabrication cost all of which collectively hinder device reliability and scalability. We also explore the latest strategies developed to address these challenges, including novel doping techniques to realize p-type behavior, thermal management solutions, defect passivation approaches, and innovations in selective etching and surface treatment. In addition, alloying strategies involving elements such as aluminum (Al) and iridium (Ir) are discussed for their potential to tune material properties, mitigate limitations, and enhance overall device performance. By consolidating recent advancements and addressing the remaining bottlenecks, this review aims to provide a comprehensive perspective on the state-of-the-art in Ga₂O₃ research. It offers valuable insights for both academic researchers and industry professionals working toward the realization of commercially viable Ga₂O₃-based power electronic devices.