Growth of Various Phases of Gallium Oxide

Abstract In this article, we review the growth of various phases of gallium oxides (Ga 2 O 3 ). There are five polymorphs of Ga 2 O 3 , α, β, γ, δ, and ϵ (or κ), of which β‐gallia is the most thermodynamically stable one. In the past decade, remarkable advancements in producing β‐Ga 2 O 3 bulk substrates have been made. At present, 4‐inch β‐Ga 2 O 3 substrates are commercially available. The other phases of Ga 2 O 3 are less thermally stable; however, the material properties of different crystal structures suggest their potential for a broad range of applications. In order to better understand the characteristics of various phases of Ga 2 O 3 , growth methods for bulk and epitaxial thin films of Ga 2 O 3 and structural properties are reviewed herein.