Interface reconstructed structure of Ag/Si(111) revealed by X-ray diffraction

We studied a buried interface reconstructed structure of the Ag/Si(111)3×3–Ag samples using grazing incidence X-ray diffraction with synchrotron radiation. We found that the 3interface superstructure can be explained by an inequivalent-triangle (IET) model, which has been observed on the Si(111)3×3–Ag surface at low substrate temperatures by STM. The calculated structure factors of the IET model were found to be very close to our observed ones. The reliability factor (R-factor) using the IET model was about 25%. The R-factor was improved to be much less value, 12% by considering defects of Ag atoms forming the 3structure. The Patterson map expected from the IET model having the defects was very similar to that calculated from the observed structure factors.