Beta-Gallium Oxide Material and Device Technologies

Beta-gallium oxide (β-Ga 2 O 3 ) is a material with a history of research and development spanning about 70 years; however, it has attracted little attention as a semiconductor for a long time. The situation has changed completely in the last ten years, and the world has seen increasing demand for active research and development of both materials and devices. Many of its distinctive physical properties are attributed to its very large bandgap energy of 4.5 eV. Another important feature is that it is possible to grow large bulk single crystals by melt growth. In this article, we first discuss the physical properties of β-Ga 2 O 3 , which are mainly important for electronic device applications, bulk melt growth, and thin-film epitaxial growth technologies. Then, state-of-the-art β-Ga 2 O 3 transistor and diode technologies are discussed.