Modeling of SiO 2/Si(100) interface structure by using extended -Stillinger-Weber potential

Abstract

Large scale modeling of ultrathin SiO 2 films on Si(100) surfaces has been performed using our original potential, which was developed to simulate both Si and SiO 2 crystal systems. A SiO 2 film was formed by layer-by-layer insertion of oxygen atoms into Si-Si bonds in a Si wafer from one of the surfaces. The thickness of the obtained SiO 2 layer was about 17.2 Å, and it showed the presence of the structural transition layer; the average Si O Si bond angle becomes smaller in the region closer to the SiO 2/Si interface. The peak of Si O Si bond angle distribution is shifted toward a narrower angle from the equilibrium angle of 144 °, in agreement with experimental results reported so far.