Progress of Ultra-Wide Bandgap Ga₂O₃ Semiconductor Materials in Power MOSFETs

As a promising ultra-wide bandgap semiconductor, the β-phase of Ga2O3has attracted more and more interest in the field of power electronics due to its ultra-wide bandgap (4.8 eV), high theoretical breakdown electric field (8 MV/cm), and large Baliga's figure of merit, which is deemed as a potential candidate for next generation high-power electronics, including diodes, field effect transistors (FETs), etc. In this article, we introduce the basic material properties of Ga2O3, and review the recent progress and advances of β-Ga2O3based metal-oxide-semiconductor field-effect transistors (MOSFETs). Due to the problematic p-type doping technology up to now, the enhancement-mode (E-mode) β-Ga2O3FETs face more difficulties, compared with depletion mode (D-mode). This article focuses on reviewing the recent progress of E-mode Ga2O3MOSFETs, summarizing and comparing various feasible solutions when p-type doping is absent. Furthermore, the device fabrication and performances of state-of-art β-Ga2O3MOSFETs, including D-mode, E-mode, and planar/vertical structure are fully discussed and compared, as well as potential solutions to the challenges of Ga2O3FETs.