Antiphase domain boundary formation in single-crystal chalcopyrite-structure ZnGeAs2 grown on GaAs

Abstract
Using transmission electron microscopy we have observed antiphase domain boundaries in single‐crystal (001) ZnGeAs2 grown on vicinal (100) GaAs by organometallic vapor phase epitaxy. These antiphase domains boundaries pertain only to the cation sublattice of the chalcopyrite‐structure ZnGeAs2 and are initiated at the heteroepitaxial interface because there exists a level of ordering on the cation sublattice in the ZnGeAs2 epitaxial film that is absent in the GaAs substrate. There are two possible types of displacement vectors characterizing these antiphase domain boundaries, and a zinc‐blende‐structure substrate orientation to eliminate the boundaries is suggested.