Depletion-mode Ga2O3 MOSFETs

We have been proposing a new oxide compound semiconductor, gallium oxide (Ga<sub>2</sub>O<sub>3</sub>), as a promising candidate for power device applications because of its excellent material properties and suitability for mass production. The 4.8-eV bandgap and the Baliga's figure of merit of Ga<sub>2</sub>O<sub>3</sub> are much larger than those of SiC and GaN, which will enable Ga<sub>2</sub>O<sub>3</sub> power devices with higher breakdown voltage and efficiency than SiC and GaN devices. The other important advantage of Ga<sub>2</sub>O<sub>3</sub> is that a single-crystal bulk can be grown by using the same melt growth method as is used for sapphire. Therefore, Ga<sub>2</sub>O<sub>3</sub> power devices have the obvious potential to surpass SiC and GaN in not only device performance but also cost effectiveness. In this work, we fabricated and demonstrated depletion-mode Ga<sub>2</sub>O<sub>3</sub> metal-oxide-semiconductor field-effect transistors (MOSFETs).