Direct observations of atomic structures of defects in GaN by high-resolution Z-contrast STEM

摘要

GaN/(0001) Sapphire grown by low pressure MOVPE is studied by high resolution Z-contrast imaging using STEM. First direct observation of the threading dislocation with edge character shows the atomic core structure, which appears to have a similar configuration to the (l brace)10-10(r brace) surface. The surfaces of the nanopipe walls are on (l brace)10-10(r brace) with the terminating layer between the atoms with one bond per pair. In addition, the high resolution Z contrast image of the prismatic stacking fault confirms the results by conventional HRTEM.