【Device Papers】Band alignment of Cr₂MnO₄ on (-201) and (001) β-Ga₂O₃

      Researchers from the University of Florida have published a dissertation titled "Band alignment of Cr₂MnO₄ on (-201) and (001) β-Ga₂O₃" in Journal of Vacuum Science & Technology A.

Abstract

      p-type Cr₂MnO₄ with bandgap 3.01 eV was sputter deposited onto (-201) and (001) n-type or semi-insulating β-Ga₂O₃.The heterojunction of p-type CrMnO₄ on n-type Ga₂O₃ is found to be type II, staggered gap, i.e., the band offsets are such that both the conduction and valence band edges of Ga₂O₃ are lower in energy than those of the Cr₂MnO₄. This creates a staggered band alignment, which can facilitate the separation of photogenerated electron-hole pairs. The valence band edge of Cr₂MnO₄ is higher than that of Ga₂O₃ by 1.82–1.93 eV depending on substrate orientation and doping, which means that holes in Cr₂MnO₄ would have a lower energy barrier to overcome to move into Ga₂O₃. Conversely, the conduction band edge of Cr₂MnO₄ is higher than that of Ga₂O₃ by 0.13–0.30 eV depending on substrate doping and orientation, which would create a barrier for electrons in Ga₂O₃ to move into Cr₂MnO₄. This heterojunction looks highly promising for p-n junction formation for advanced Ga₂O₃-based power rectifiers.

DOI：

https://doi.org/10.1116/6.0004591