A state-of-art review on gallium oxide field-effect transistors

As a promising ultra-wide bandgap (UWBG) semiconductor, gallium oxide (Ga2O3) has recently aroused increasing attention in the area for high-power electronics, power switch for radio frequency (RF) operation, and solar blind UV detectors. The beta-phase of Ga2O3 is deemed as a potential candidate for next generation high-power electronics due to its high theoretical breakdown electric field (8 MV cm(-1)), UWBG (4.8 eV), and large Baliga's figure of merit. Owing to the intensive research efforts across the world since 2013, gallium oxide transistors recently make rapid advances in device design and performance. Until now, high quality large-size bulk Ga2O3 and n-type epi products are successively coming onto the market, as well as there are gratifying progress worldwide to develop more complex epi structures, including beta-(Al (x) Ga1-x )(2)O-3/Ga2O3, beta-(In (x) Ga1-x )(2)O-3/Ga2O3, n-Ga2O3/p-NiO, beta-Ga2O3/4H-SiC heterostructures et al. In this paper, the basic physical properties of Ga2O3, and the recent research process of Ga2O3 based transistors field-effect transistor (FET) for high-power electronics and RF are introduced. Furthermore, various state-of-the-art structures and process used in Ga2O3 based FETs have been summarized and compared, including planar/vertical metal-oxide-semiconductor field-effect transistor (MOSFET), trench MOSFET, FinFET, modulation-doped FET or called it high electron mobility transistors with two-dimensional electron gas channel, SOI MOSFET, thus the potential of Ga2O3 FETs is preliminary revealed. Finally, the prospect of the Ga2O3 based FET for high-power and RF application will be also analyzed.