Synchrotron x-ray topography analysis of GaAs layers grown on GaAs substrates by liquid phase epitaxial lateral overgrowth

Synchrotron x-ray topography techniques in section and back-reflection geometries have been applied to silicon and tin doped GaAs layers grown by the liquid phase epitaxial lateral overgrowth (ELO) technique on (100) GaAs substrates. Back-reflection topographs show that the laterally grown parts of the ELO layers are nearly dislocation free in spite of a large density of defects in the substrate. Section topographs reveal novel and unique features which are attributed to the bending of the ELO layers induced by their interaction with the SiO₂ mask.