SiO2/Si(100) Interfacial Lattice Strain Studied by Extremely Asymmetric X-ray Diffraction

We studied the interfacial lattice strain of SiO2/Si(100) formed by high-pressure oxidation with extremely asymmetric X-ray diffraction using synchrotron radiation. From the dynamical diffraction calculation, we analyzed that the lattice spacing of oxidized silicon is compressed compared to that of the ideal crystal. By comparing wavelength dependence of integrated intensities of rocking curve obtained by calculations and experiments, we found that the conditions during oxidation influenced the magnitude of the lattice strain. The higher the oxygen pressure was the more compressive strain was introduced. Moreover, for higher temperature, more compressive strain was introduced. The interfacial lattice strain introduced in high pressure oxidation is comparable in magnitude to that introduced in dry oxidation even if the oxidation done at low temperatures.