Tin-Assisted Synthesis of ε−Ga2O3 by Molecular Beam Epitaxy

Metastable $ϵ$-gallium oxide is expected to have very good properties for high-power electronics, combining the large band gap and high breakdown field of $\ensuremath{\beta}$-Ga${}_{2}$O${}_{3}$ with a very high spontaneous polarization. Unfortunately, synthesizing $ϵ$-Ga${}_{2}$O${}_{3}$ is quite tricky, yet the authors have managed it. Introducing tin avoids the formation of volatile suboxides, which leadsto a widened growth window in which $ϵ$-gallium oxide can beformed. Furthermore, the growth mechanism that the authors revealcould be relevant for the growth of any binary oxide.