On the successful growth of bulk gallium oxide crystals by the EFG (Stepanov) method

Abstract

Bulk crystals of [Formula: see text]-Ga2O3 were successfully grown by the EFG (Stepanov) method. Analysis of the material using an X-ray diffraction showed the high crystalline quality of the obtained crystals. However, when determining the elemental composition by the Energy Dispersive X-ray Spectroscopy (EDS) method, a deviation of the crystal composition from a stoichiometric one was found and a lack of oxygen was detected. Indirectly, this indicates the non-optimal composition of the atmosphere in the growth zone. The origin of this deviation of the composition can be oxygen vacancies in the bulk of the crystal. However, the absorption spectrum does not contain peaks characteristic for oxygen vacancies in gallium oxide. An analysis of the optical transmission spectra made it possible to estimate the optical bandgap of the grown gallium oxide samples, which was 4.7 eV.