Silicon-silicon bonds in the oxide near the SiO2/Si interface

Abstract The contribution of the SiO 2 /Si interface structure to optical absorption below the optical absorption edge of fused quartz was studied by measuring the reflectance of thermally grown ultrathin silicon oxide films. From the modified Kramers-Kronig analysis of reflectance, it was found that optical absorption at the photon energy of 7.8 eV arises from Si Si bonds in the oxide film within 1.4 nm of the interface. The approximate areal density of Si Si bonds is 7 × 10 14 cm −2 and is approximately equal to the areal density of silicon su☐ides determined by X-ray photoelectron spectroscopy.