Strain in GaAs layers grown by liquid phase epitaxial lateral overgrowth

High resolution x-ray diffraction has been used to study strain in GaAs layers grown on GaAs substrates by the liquid phase epitaxial lateral overgrowth (ELO) technique. We show that the lattice and thermal expansion coefficient mismatch between the subsequent layers and the substrate, as well as the built-in strain in the SiO2 masking film, lead to long-range deformations (macroscopic bending) extending over the whole area of the sample. Moreover, we show evidences that microscopic bending of individual ELO stripes takes place due to adhesion of their laterally overgrown parts to the masking film.