Abstract
In our previous study, we found that magnetite is epitaxially grown on GaAs substrate pre-annealed in air. While the formation of an oxidized layer is confirmed on GaAs by electron microscopy, the composition and crystal structure was unknown. In this study, the oxidized layer is revealed to be β-Ga2O3, of which (100) plane is parallel to the substrate plane by x-ray and electron diffractions. It disappears during the sputter deposition of magnetite on it, and a clear Fe3O4/GaAs interface is formed. The epitaxial relationship of the Fe3O4/GaAs heterostructure is cube-on-cube in contrast to that fabricated by a conventional method.
