The composition of octahedron structures that act as an origin of defects in thermal SiO2 on Czochralski silicon

Recently, octahedron structures have been found in the Czochralski-silicon substrate surface layer just under the oxide defects. An attempt is made to characterize these structures by analysis with transmission electron microscopy and energy-dispersive x-ray spectroscopy. Several results indicate that the structure is full of vacancies. This is contrary to previously reported results suggesting that the octahedron structures found in Si bulk are filled with amorphous SiO2. A model for the formation of an octahedron structure with many vacancies is proposed.