Relaxation of an epitaxial InGaAs film on a thin twist-bonded (100) GaAs substrate

A 30 nm (100) GaAs layer was transferred by twist wafer bonding to a (100) GaAs handling wafer. A similar structure was proposed in the literature as a “compliant substrate.” Transmission electron microscopy and x-ray diffraction of 40 and 300 nm epitaxial InGaAs films (0.5% misfit) showed no evidence of a relaxation mechanism specifically attributed to a compliant substrate. The 40 nm film was nearly pseudomorphic without any evidence of a relaxation mechanism, like grain-boundary sliding. The possibility of grain-boundary slip along the twist-bonded interface is discussed.