EFFECTS OF BUFFER LAYER ON FORMATION OF DOMAIN BOUNDARIES IN EPILAYERDURING FILM GROWTH OF GAN BY LOW-PRESSURE METAL-ORGANIC VAPOR-PHASE EPITAXY ON SAPPHIRE SUBSTRATES

Twinning was observed in a GaN buffer layer. The twin boundaries in th e buffer layer can extend into the epitaxial layer to form domain boun daries during growth of the epilayer. The domain boundaries, which ini tiated from the twin boundaries in the buffer layer, are determined to be inversion domain boundaries. (C) 1997 American Institute of Physic s. [S0003-6951(97)01151-0].