Monocrystalline thin films were grown onto GaAs(100) by means of molecular beam epitaxy under a Se-rich atmosphere. Reflection high-energy electron diffraction analyses suggested that the Ga2Se3 thin films were epitaxially grown onto GaAs(100), with their <100> axes aligned with each other. Transmission electron microscopy showed that vacancies were distributed on one set of {111} crystal planes of the a-Ga2Se3 structure, and formed a v3 x v3 configuration. This resulted in a 3-times larger modulation periodicity along one of the <110> crystal directions in vacancy-ordered a-Ga2Se3. There were 2 sets of planar defects: micro-twins with {111}-type twin planes, and stacking faults. The large populations of planar defects which were observed in the thin films were regarded as being the result of Ga vacancy ordering.

Growth and Characterization of Ga2Se3/GaAs(100) Epitaxial Thin Films K.Ueno, M.Kawayama, Z.R.Dai, A.Koma, F.S.Ohuchi: Journal of Crystal Growth, 1999, 207[1-2], 69-76