Carbon in Grown-in Defects in Czochralski Silicon and Its Influence on Gate-Oxide Defects

We systematically investigated the impurities situated in the octahedral void defects in Czochralski silicon crystal by using electron energy-loss spectroscopy and Auger electron spectroscopy. As a result, we found that carbon cohesion was observed on the inner walls of the void defects. The carbon concentration on the inner walls was estimated to be about 2×1014/cm2. This result suggests that void defects with this amount of carbon could seriously affect the integrity of gate-oxides of metal-oxide-silicon integrated circuits.