Structural Characterization of GaAs Layer Grown on 2D-GaSe/Si(111) Substrate for Rapid Epitaxial Lift Off

We have developed a rapid ELO technique using mechanical cleavage via 2D-layered metal selenide inserted between the III-V epitaxial layer and the substrate. In this technique, processing time is only a few seconds. The key issue is the crystal quality improvement of the GaAs layer. As 2D-layered metal selenide, double 2D-buffer layers of GaSe and In2Se3 were grown on Si(111) substrate by MBE. The 180
^o
rotational twin formation and dislocations in GaAs layer were characterized by XRD pole figure and cross-sectional TEM. The twin ratio was estimated to 12%. These twin domains are mainly distributed near the bottom interface. To reduce dislocation density, it is necessary to suppress the twin formation at the interface.